Displacement ENcoding with Stimulated Echoes (DENSE) is an MRI technique developed to encode phase related to myocardial tissue displacements, and the displacement information directly applied towards detecting left-ventricular (LV) myocardial motion during the cardiac cycle. The purpose of this study is to present a novel, three-dimensional (3D) DENSE displacement-based and magnitude image quantization-based, semi-automated detection technique for myocardial wall motion, whose boundaries are used for rapid and automated computation of 3D myocardial strain.N = 14) healthy subjects. Chamber quantifications between methods were compared using paired t-tests and Bland–Altman analysis established regional strain agreements.The architecture of this boundary detection algorithm is primarily based on pixelwise spatiotemporal increments in LV tissue displacements during the cardiac cycle and further reinforced by radially searching for pixel-based image gradients in multithreshold quantized magnitude images. This spatiotemporal edge detection methodology was applied to all LV partitions and their subsequent timeframes that lead to full 3D LV reconstructions. It was followed by quantifications of 3D chamber dimensions and myocardial strains, whose rapid computation was the primary motivation behind developing this algorithm. A pre-existing two-dimensional (2D) semi-automated contouring technique was used in parallel to validate the accuracy of the algorithm and both methods tested on DENSE data acquired in (vs 0.60 ± 0.06 (p = 0.23) for apical, 0.60 ± 0.04 vs 0.59 ± 0.05 (p = 0.76) for midventricular and 0.56 ± 0.04 vs 0.58 ± 0.05 (p = 0.07) for basal segments, that were quantified using the 3D semi-automated and 2D pre-existing methodologies, respectively. Bland–Altman agreement between regional strains generated biases of 0.01 ± 0.06, –0.01 ± 0.01 and 0.0 ± 0.06 for the radial, circumferential and longitudinal directions, respectively.There were no significant differences in the results of chamber quantifications between the 3D semi-automated and existing 2D boundary detection techniques. This included comparisons of ejection fractions, which were 0.62 ± 0.04 A new, 3D semi-automated methodology for contouring the entire LV and rapidly generating chamber quantifications and regional strains is presented that was validated in relation to an existing 2D contouring technique.This study introduced a scientific tool for rapid, semi-automated generation of clinical information regarding shape and function in the 3D LV. In this regard, DENSE is a sequence that can ideally be used to automate all computations, including boundary detection, determination of functional parameters as well as chamber quantifications, an approach which was demonstrated in a two-dimensional (2D) semi-automated motion estimation study by Spottiswoode et al.11The quantification of cardiac chamber dimensions and function is the foundation of cardiac imaging, of which MRI is the most reliable modality, providing superior resolution for soft-tissue contrast and multiplanar information that cannot be delivered by other modalities.15 The displacement-based boundary search is further reinforced with a histogram distribution-based, multilevel thresholding-based image compression approach called Otsu’s method that was applied to identify myocardial tissue according to a discrete range of quantized indices.17 In this regard, presented here is the first 3D, single-scan DENSE study that applies spatiotemporal displacements and the semi-automatedly detected LV boundaries toward rapid and automated 3D strain analysis and generation of surface strain maps.10 Validation is provided by comparing the LV chamber quantifications and 3D strains computed with this new 3D methodology to those generated using the fully validated 2D boundary detection approach developed by Spottiswoode et al.22This study was conducted to investigate the feasibility of a highly automated, single-scan, MRI-based methodology for assessing full LV function (stain-based contraction and chamber quantifications), whose unprecedented rapid processing time (3.5 min approximately) might be of significant advantage in clinical applications. To achieve this goal, a novel and fast three-dimensional (3D) semi-automated methodology was used that primarily tracks LV boundary motion (during cardiac systole) using phase-encoded 3D displacement data recorded with the navigator-gated spiral DENSE MRI sequence.12,19 Typical imaging parameters included field of view of 380 × 380 mm2, echo time of 1.04 ms, repetition time of 15 ms, matrix size of 128 × 128 × 19, 2.97 × 2.97 × 5 mm3 voxel size, 21 cardiac phases, encoding frequency of 0.06 cycles mm-1, simple 4-point encoding and 3-point phase cycling for artifact suppression.15,23 Given that three heartbeats are needed to acquire a complete set of spirals for a single displacement encoding direction and a single phase cycling point, the number of navigator-accepted heartbeats to complete a single partition in 3D is (4 × 3 × 3) = 36 heartbeats.15 Hence, the acquisition time per subject was about 15 min depending on the heart rate and navigator acceptance rate of individual subject. Continuous monitoring of heart rates and blood pressures were conducted during the scans for all subjects.Navigator-gated 3D DENSE data were acquired with displacement encoding applied in two orthogonal in-plane directions and one through plane direction. A flexible, anterior 6-channel body matrix radiofrequency coil  and the table-mounted spine matrix radiofrequency coil were used for receiving signals.17 In its most basic form, the Otsu algorithm separates two classes of pixels based on a bimodal histogram (foreground and background), and calculates the optimum threshold separating the two classes such that their interclass variance is maximal.17 The maximizing interclass variance, σb, in Otsu’s method, in an image of pixel intensities ranging from i = 1, .., L, is given by,Identification of the LV boundary contours in each short axis slice (image) at a reference timeframe (end-diastole) is the first step in this semi-automated process. This process occurred by the operator selecting an ellipsoidal region of interest (ROI) in the most basal short-axis slice shown in  at end-dω0 and ω1 are the probabilities of the two classes separated by a threshold, t, and defined aswhere weights pi is the probability of intensity i in the image and µ0 and µ1 are the class means given by,where L is the total number of bins in the original histogram.where t1, t2, …, tM-1), which divide the original image into M classes.16 In this case, the maximizing interclass variance is given by,The previous formula can be easily extended to multilevel thresholding as was done for this study. The multilevel method assumes that there are M-1 thresholds,  is attainable only by images having a single gray level, and the upper bound is attainable only in binary images.25 To briefly explain the LOESS fit, for each boundary point a low-degree polynomial is least square fitted to a subset of boundary points, with explanatory variable values near the point whose response is being estimated.25 In addition, the subsets of points used for each weighted least squares fit are determined by a nearest neighbors algorithm and a smoothing parameter, α , which determined how much of the data points would be used to fit each local polynomial. In this way, and by specifying a maximum number of iterations, a new peak was selected every time it reduced the following error term, ε, defined as,One of the fundamental mechanisms of edge detection in images involve identifying sudden changes in intensities in a cluster of local pixels. This concept can be applied towards detecting myocardial boundaries in a quantized image with a limited number of pixel intensities. When pixel-based intensity gradients are computed in a radial direction, starting with points on a bounding ellipse and moving across the LV myocardium, local peaks are created where there are abrupt changes in intensities, as shown in rp is the location of the 2D slice-based peak and rL is the location of the LOESS point.where 26 DENSE employs the pulsed gradient stimulated echo technique to encode tissue displacement in the phase of the stimulated echo, thus enabling the acquisition of pixelwise tissue displacements from which the semi-automated frame-by-frame myocardial boundary motion is finally derived. Hence, the new position of a boundary control point can be found by tracking pixels with displacements, whose tails map back to an original boundary control point at end-diastole.12,15 Detailed descriptions for phase-to-displacement conversions with pixelwise phase unwrapping can be found in several previous publications, including our studies in DENSE-based strain validation.12,15,18 A final step involves refining the raw displacement data using temporal fitting of each pixel’s trajectory with Fourier (fifth order) basis functions as described in previous studies.15,18,19 The series of images in e.g. blood pool or chest cavity), the point is relocated to the closest pixel whose quantization index falls within the myocardial range. LOESS curve fits are once again applied to each boundary following the finding of new material-based boundary points in each subsequent timeframe.In this study, soft tissue deformation quantified by its influence on both signal amplitude and phase was the primary driver for assessing cardiac kinematics and boundary motion in a semi-automated manner. Precisely, the background to measuring deformation fields in DENSE is a well-established magnetic field gradients/Fourier Transform methods phenomenon called the pulsed gradient stimulated echo, incorporating motion encoding by employing a pair of pulsed field gradients.29 Individuals who have 2 or more years of experience in DENSE post-processing randomly performed boundary detections with this 3D semi-automated process. The individuals consisted of two graduate students (one each from engineering and medicine) and an individual with a doctorate in biomedical engineering. Hence, an individual who has a graduate background in science or technology is suitably qualified to perform this post-processing.Following the generation of boundaries for all partitions and time frames, as well as 3D reconstruction using existing techniques, measurements for chamber quantifications for specific parameters, such as LV wall thickness, end-diastolic diameter (EDD), end-systolic diameter (ESD), end-diastolic volume (EDV), end-systolic volume (ESV), ejection fraction (EF) and LV mass were conducted using guidelines provided in gold-standard MRI studies.12 A more comprehensive summary regarding the Spottiswoode et al approach to automatic spatiotemporal tracking of 2D myocardial material points from cine DENSE displacement observations can be found in their original articles. With this technique, epicardial and endocardial contours must be initialized manually for each partition prior to computing phase-based displacements for detecting boundaries in subsequent time frames. The displacement vector starting points in subsequent phases is, therefore, determined by this myocardium at t0, and tracking these points though time identified the position of the myocardium in the following frames. However, they found that obtaining suitable motion trajectories from noisy displacement fields required a number of refinements to the motion tracking algorithm. Hence, to accurately track myocardial tissue motion, noisy displacement vectors were first removed using a modulus deformation mask, which was obtained for each frame by combining orthogonal spatial derivatives of the displacement fields.10 Remaining noisy vectors were then eliminated based on their deviation from the mean magnitude and angle of nearby vectors and a cluster of vectors with tails nearest to each starting point at t0 selected to refine displacement.12 Trajectories were further improved by applying temporal fitting as described in Spottiswoode et al with periodic Fourier basis functions fitted to each horizontal and vertical components of motion as a function of time.12 Reconstructing the 3D LV geometry with the estimated 2D myocardial boundaries was conducted using the same technique as used for this study’s 3D semi-automated process.19 Following this, pixelwise 3D strain tensors were computed using the meshfree Radial Point Interpolation Method (RPIM) methodology and the strains averaged for the 16 standard myocardial segments. The generation of myocardial boundaries using this technique was performed in a random fashion by the same individuals who conducted the boundary assessment for the new 3D semi-automated technique. A summarized comparison between this study’s 3D semi-automated technique and the Spottiswoode et al methodology is given in Given here is a summarized description of the 2D automated DENSE-based boundary detection technique by Spottiswoode et al in reference to which the currently proposed 3D semi-automated technique was validated.20,22,30,31 Since RPIM shape functions have the Kronecker delta functions property, essential boundary conditions are simply enforced, as otherwise done in finite element analysis. Hence, combining the advantages of DENSE with RPIM provides fast and effective 4D spatiotemporal analysis of strain, readily computed at a given voxel, and without the tedium of keeping track of tagged data or remeshing interventions that otherwise prolong modelling time in traditional finite element analysis.14 Extensive descriptions of both RPIM and its use in computing 3D LV strains is outlined in previous literature, which in particular details the use of the Multiquadrics as radial basis function shape function that ensure C1 continuity.22,31 For the final comparison of strains between the two methodologies, the LV was segmented into 16 standard regions and the mean strain estimated for each from the grid-point values.Three-dimensional strain parameters  were computed using RPIM at each voxel in patient-specific MRI-based reconstructed 3D grid geometries. RPIM is a numerical analysis technique based on the Galerkin weak form that uses radial basis functions as 3D meshfree shape functions and facilitates fast multidimensional computation of Lagrangian strains.t-tests, where the key parameters included wall thickness, EDD, ESD, EDV, ESV, EF and LV mass. The estimated parameters were also compared to gold-standard measurements reported in previous MRI studies.34 Additionally, Bland–Altman analysis provided the measure of agreement between RPIM-based 3D strains, in the radial, circumferential and longitudinal directions, from the two contouring techniques. The strain results were also non-empirically compared to measurements reported in previous tissue tagging studies and to those from validation studies in 3D DENSE.19,35The LV chamber quantification results from the 3D semi-automated and Spottiswoode et al contouring techniques were compared using paired The average age of the subjects was 30.5 ± 7.8 years and body weight was 65.8 ± 9.6 kgs . Monitored mean heart rate from all studies was 66.6 ± 8.0 bpm while mean blood pressure was 120.0 ± 16.7/77.3 ± 15.1 mmHg.vs 7.9 ± 1.5 mm (p = 0.12), midventricular segment at 7.7 ± 1.4 vs 7.8 ± 1.3 mm (p = 0.69) and basal segment at 7.8 ± 1.6 vs 7.6 ± 1.5 mm (p = 0.83), respectively. Other fundamental measurements for which significant differences were not found between the methodologies include apical EDD (p = 0.19), midventricular EDD (p = 0.63), basal EDD (p = 0.10), apical ESD (p = 0.14) and midventricular ESD (p = 0.52), with the only exception seen in the basal ESD (p = 0.04). Next, the fundamental dimensions were applied towards computing 3D chamber dimensions such as volume, ejection fraction and mass for both techniques, estimates of which are given in t = 15 ms). Also shown in The full LV chamber quantification, from both 3D semi-automated and Spottiswoode et al boundary contouring methods, are given in The left hand side of 10,12 The results showed the fundamental geometric and functional properties such as LV wall thickness, EDD, ESD, EDV, ESV, EF, LV mass and 3D strains were not significantly different between the measurement types  were compared and close agreements established between the two contouring techniques  can be justified for DENSE as it provides the critical displacement and strain data which a faster SSFP sequence cannot. Furthermore, research is now underway for faster DENSE imaging using technologies such as compressed sense with parallel imaging that deliver high quality images while reducing scan time.40Several studies in recent years have emphasized the importance of strain analysis as a subclinical measure for identifying as well as measuring therapeutic progress in cardiac dysfunctions such as ischemia, hypertrophic cardiomyopathy, dilated cardiomyopathy and others.12 A second important difference with the 2D Spottiswoode et al method lies in the use of the complementary technique used to refine myocardial extent in addition to phase based displacements. In this context, the Spottiswoode et al method used a modulus deformation mask with which all deformation in excess of the expected myocardial range is rejected, which in turn helped define myocardial extent. Whereas, the new 3D semi-automated technique uses a magnitude image based multithreshold quantization technique and its gradients found in a radial search path to help determine myocardial extent. One of the main similarities to the Spottiswoode et al method lies in regard to finding material point displacements from displacement vectors with tails originating at a reference point on the myocardial boundary and in how only vectors closest in angular orientation and magnitude are used for approximating the location of a new boundary point.12,18,19,39 The existing 2D technique also applies some effective noise removing steps associated with motion-based trajectories, including fitting of each trajectory with periodic Fourier series basis functions, which was a technique also used for refining pixelwise trajectories for this study. A final observation made in relation to the comparing the two techniques is the negligible differences in results between them, which can be attributed to conducting this study in healthy young subjects whose ventricular shape and pattern fall within a predefined range. It is hypothesized that there would be higher differences in results between the two techniques in a population with known cardiac disease, in which case significantly more measurement errors could be introduced by a 2D technique that requires more frequent human interactions (at each 2D partition).Given next is a summary description of the similarities and differences between the existing 2D method by Spottiswoode et al and the new 3D semi-automated boundary detection method presented here, and also provided in tabulated form in p-value). The aspects of this limitation are attributed to image degradation induced by cardiac and respiratory motion whose effects include blurring  and which in turn effect quantization thresholds.41 In this context, if a low resolution blur is quantized below a threshold that identifies intramyocardial tissue, the result will be a reduction in thickness. On the other hand, a blurred tissue–blood interface with high resolution may be erroneously recruited as intramyocardial tissue resulting in a perceived increase in thickness. In order to avoid such anomalies, methods to improve image-based signal degradations need to be addressed with respect to the original sequence and its parameters.23,41 Another limitation of this study was in not comparing the current quantization and deformation-based approach to a more traditionally used semi-automation process such as the Active Appearance Model (AAM).43 However, there are some apparent drawbacks to AAMs, including the requirement of a training set that can give rise to implausible statistical outliers, and AAMs’ sensitivity to initialization errors can lead to errors related to translation, rotation or scaling.44 On the other hand, AAM models are built on strong statistical foundations and can withstand substandard quality of data, including missing texture information. In contrast, the current 3D semi-automated technique will fail to model the morphology of the LV if either magnitude or phase information is incomplete. A related limitation is not arduously pursuing other thresholding methods that have been effective for anatomical pattern recognition in medical images. The two commonly used thresholding algorithms, K-mean (each data point is a member of only one cluster) and Fuzzy C-means  have previously been used in automated detection of the LV lumen but were not considered for this study.47 A final limitation lies in not conducting gold-standard SSFP studies for LV chamber quantifications. SSFP is the gold-standard measurement technique for chamber quantification and there exists a strong likelihood of seeing significant differences between chamber quantifications by SSFP and the current 3D semi-automated technique.29,33 However, SSFP cannot be used for comprehensive LV contraction analysis and is unable provide the displacement data required for the combined purposes of both boundary detection and strain analysis, which is possible with the DENSE-based 3D semi-automated technique.The most important limitation of this methodology is the requirement of an ROI (bounding ellipse) at the start of segmentation, where a pattern-based search for a torus to locate the LV in short axis slices will make this algorithm a fully automated one. However, the search for a complex torus shaped LV of non-uniform thickness in an uncropped image can become a computationally demanding process and ultimately prolong the time for generating the 3D contours. Secondly, quantization itself can pose a challenge when the picture quality varies significantly between subsequent timeframes or partitions, in which case, the algorithm must address variations in multithreshold based indices that identify the myocardium, and, in particular, when optimal quantization computations are used for thresholding individual image. A third limitation was the observed difference in fundamental parameters such as LV thickness between 3D semi-automated and Spottiswoode et al contouring techniques in the apical segment  for 3D contouring the full LV. Furthermore, the rapid contouring process achieved within a short time period of less than 3 min is followed by automated chamber quantifications and generation of 3D strain maps. This 3D semi-automated technique was validated by comparison to an existing 2D semi-automated contouring technique and similarities in cardiac chamber quantifications and strain evaluations were seen between the two techniques. A step forward from here will be to validate the current approach in patients with known cardiac dysfunctions such as arrhythmias and cardiomyopathies. A final conclusion is that this new approach can be used to provide rapid ground-truth information regarding 3D cardiac function when data are obtained using a single navigator-gated DENSE scan.


This study evaluated the prognostic implications of post-percutaneous coronary intervention (PCI) neutrophil-to-lymphocyte ratio (NLR) in patients with acute myocardial infarction (AMI). A total of 309 patients with AMI who underwent cardiac magnetic resonance imaging (CMR) and a complete blood cell count within 24 hours before and after PCI were enrolled. Primary outcome was infarct size. Patients were assigned to high (n = 118) or low (n = 191) NLR groups according to the best cut-off value of 3.88. Infarct size  was significantly higher in the high NLR group than in the low NLR group . Post-PCI NLR ≥ 3.88 was associated with risk of a large-sized infarction (≥20%) . The risk of MACE was also significantly higher in the high NLR group than in the low NLR group . Among patients with AMI who underwent PCI, high post-PCI NLR value was associated with higher risk of large-sized infarction as measured by CMR, as well as adverse clinical outcomes. Our findings suggest that post-PCI NLR is a useful tool for risk assessment in patients with AMI who undergo PCI. Inflammation also occurs as a result of acute myocardial infarction (AMI) and plays a role in the repair and remodeling of infarcted heart tissue3. Based on this concept, several studies have investigated the associations between various inflammatory markers and clinical outcomes in patients with coronary artery disease8. Neutrophil-to-lymphocyte ratio (NLR) has emerged as an independent predictor of cardiovascular outcomes in patients with ischemic heart disease, including AMI15. Especially, post-percutaneous coronary intervention (PCI) NLR was found to be a better indicator of severity of myocardial damage than pre-PCI NLR14.Inflammation plays a role in the initiation and progression of the atherosclerotic process, which is a leading cause of coronary artery disease17. Furthermore, CMR allows quantification of the extent of area at risk and salvaged myocardium based on delayed hyperenhancement and T2-weighted images16. It is well known that infarct size has the strongest association with late systolic dysfunction and provides incremental prognostic information in addition to left ventricular ejection fraction19.Cardiac magnetic resonance imaging (CMR) is the current gold-standard technique for evaluating infarct size and transmural extent of infarction and for performing microvascular assessment in the setting of AMIThough several studies have studied the relation between NLR and clinical outcomes, the associations between post-PCI NLR and structural markers of myocardial injury measured by CMR in patients with AMI are unknown. Therefore, we sought to evaluate the relationship between post-PCI NLR and infarct size, and between post-PCI NLR and clinical outcomes in patients with AMI.20. We excluded patients who did not undergo a complete blood cell count (CBC) within 24 hours before and after PCI. A total of 309 AMI patients who underwent CMR and had pre- and post-PCI CBC data was finally included in the current study  was at the discretion of the physicians. PCI was considered successful if the final residual stenosis was <30% with Thrombolysis In Myocardial Infarction grade 3 flow. All patients who were not taking aspirin or a P2Y12 inhibitor received a loading dose of aspirin or P2Y12 inhibitor, respectively. Unless there was an undisputed reason for discontinuing dual-antiplatelet therapy, all patients were recommended to take aspirin indefinitely plus a P2Y12 inhibitor for at least 1 year after the index procedure. Medications were prescribed according to standard guidelines.Patient management was performed according to relevant standard guidelines16. Infarct size was calculated as summation of the area with delayed hyperenhancement within each segment of the short-axis images. This value was multiplied by slice thickness to cover the entire left ventricle. Endocardial and epicardial borders were then summed to calculate left ventricle myocardial volume using the same method. Infarct size was expressed as a percentage of the affected left ventricular myocardial volume. MVO, which was the extent of hypoenhancement within bright regions of late gadolinium enhancement, was calculated in the same manner16. Area at risk (AAR) was quantified on T2-weighted images using a similar algorithm as above16. From these parameters, myocardial salvage index (MSI) was derived as follows: MSI = (AAR-infarct size)/AAR16.CMR was performed using a 1.5-T scanner  and analyzed using validated software . Two experienced radiologists who were blinded to the clinical information measured CMR parameters using the software mentioned above . Other secondary outcomes were MVO, AAR, MSI as assessed by CMR, and each component of MACE. All clinical outcomes were defined according to the Academic Research Consortium25. The best cut-off value was used to divide the enrolled patients into the two groups.Simple linear regression analysis was performed to determine the association between post-PCI NLR and infarct size. Receiver-operating-characteristic (ROC) curve analysis was performed to determine the best cut-off value of post-PCI NLR to predict a large-sized infarction as measured by CMR. A large-sized infarction was defined as an infarction involving ≥20% of the total left ventricular mass, which was a median value in a previous studyContinuous variables were compared using Student’s t-test, and categorical variables were tested using the Chi-square test. Multivariable logistic regression analysis was performed to identify independent predictors of large myocardial infarct . We included in the multivariable models those covariates that were significant in univariate analysis or those that were clinically relevant.Cumulative event rates of clinical outcomes were calculated Kaplan-Meier estimates, and significance levels were assessed with log-rank tests. Hazard ratios (HR) and 95% confidence intervals (CI) were calculated by Cox proportional hazards models to compare clinical outcomes that occurred after the index procedure, between the two groups. The time-to-event was measured as days in Cox proportional hazards models. Multiple sensitivity analyses, namely multivariable adjusted Cox proportional hazard regression and inverse-probability-weighted (IPW) analyses, were performed to adjust baseline differences in both groups. Standardized mean differences after IPW adjustment were within ±10% across all matched covariates, suggesting achievement of balance between the two groups  and R Statistical Software .2: 0.089, p < 0.001)  after the index procedure. To find which leukocytes and differential counts accurately distinguished large-sized  infarctions, ROC curve analysis was performed. Total white blood cell counts and NLR before and after PCI were compared. Among these parameters, post-PCI NLR had the highest C-index  to discriminate a large-sized infarction, and the best cut-off value of post-PCI NLR was 3.88  and a low NLR group . Baseline clinical and angiographic characteristics are shown in Tables Laboratory, echocardiography, and CMR findings according to the NLR cut-off value of 3.88 are presented in Table Median follow-up duration was 768 days. Cumulative incidence of MACE was significantly higher in the high NLR group than in the low NLR group  Table . After aBecause presentation with STEMI is an independent predictor of large-sized infarction, subgroup analysis was performed to determine whether post-PCI NLR plays a role in risk stratification for STEMI patients. STEMI patients with NLR ≥ 3.88 had significantly larger infarct size, AAR, and MVO, consistent with findings in the larger study population (Supplementary Fig. In this present study, we evaluated the association between post-PCI NLR and infarct size as well as clinical outcomes in patients with AMI. Our key findings were as follows. First, among various pre- and post-leukocyte parameters and differential counts, post-PCI NLR showed the best ability to discriminate large-sized infarctions. Second, elevated post-PCI NLR was associated with larger infarct size and MVO and higher risk of MACE, and this association was robust after adjusting baselines using multivariable adjusted Cox regression and IPW adjustments. Third, subgroup analysis of STEMI patients revealed that infarct size was significantly larger and risk of MACE significantly higher in the post-PCI NLR ≥ 3.88 group than the post-PCI NLR < 3.88 group.26. Therefore, there have been numerous efforts to predict prognosis and improve outcomes in AMI patients28. Inflammation is not only an important cause of atherosclerosis, but also involved in the repair and adverse remodeling of infarcted heart tissue3. In this regard, interest in the role of inflammation in patients with AMI is increasing, and numerous studies have evaluated the associations between various inflammatory markers and clinical outcomes in patients with AMI15. A previous study showed that leukocyte differentials have greater predictive value of clinical outcome than total leukocyte count29. In that study, NLR was the most powerful predictor of death or myocardial infarction among various leukocyte parameters and differential counts29. In particular, Park et al. showed that post-PCI NLR was more strongly associated with mortality than baseline or pre-PCI NLR12. A possible explanation for this finding is that the time elapsed after infarction is too short for pre-PCI leukocyte profiles to fully reflect the severity of the ongoing myocardial damage. Similarly, considering that CMR was performed few days after PCI, temporal proximity may be a reason to explain that the post-PCI NLR may better reflect infarct size than the pre-PCI NLR. Furthermore, post-PCI leukocyte profiles have the advantage that they may also reflect peri-procedural myocardial damage14. In accordance with previous studies29, we showed that patients with AMI and a high post-PCI NLR had a higher risk of adverse cardiac events than those with a low post-PCI NLR. The reason for this association is that, in addition to their role in repair of the infarcted heart, leukocytes are also involved in infarct expansion30. After infarction, neutrophils release superoxide radicals, enzymes, and other metabolites that facilitate plaque disruption and lead to infarct expansion. Neutrophils aggregate with platelets and damage micro-vessels, which can also promote infarct expansion29. In addition, lymphocytes are trapped and sequestered within the myocardial microvasculature and release inflammatory mediators, contributing to further leukocyte infiltration and myocardial damage31. On this background, the results of the current study suggest that post-PCI NLR might be a predictor of clinical outcomes in AMI patients.AMI remains one of the most important causes of morbidity and mortality worldwide despite recent advances in PCI techniques and devices16. In addition, CMR has become the most accurate tool to visualize and quantify post-infarction parameters in patients with AMI18. Among post-infarction parameters, infarct size is strongly associated with mortality and hospitalization for heart failure32. Furthermore, infarct size can provide incremental prognostic information in addition to left ventricular ejection fraction, which is a well-established predictor of outcome in AMI18. Because left ventricular ejection fraction is influenced both by stunned viable myocardium and nonviable myocardium, CMR parameters can be more specific markers for determining the extent of irreversible myocardial damage33. Although several studies have investigated the association between white blood cell count and extent of infarct measured by CMR36, limited data are available regarding the association between post-PCI NLR and infarct size. Therefore, we sought to assess whether high post-PCI NLR value is associated with larger infarct size as assessed by CMR in patients with AMI. We found that high post-PCI NLR was consistently associated with larger infarct size and MVO as assessed by various tools, including cardiac enzymes, echocardiography, and CMR in patients with AMI who underwent PCI. Furthermore, there was a linear correlation between post-PCI NLR and infarct size as measured by CMR. Although the myocardial salvage index was numerically lower in the high post-PCI NLR group, this difference was not statistically significant. The results of our study suggest that post-PCI NLR, which is a simply measured marker of inflammation, can help predict infarct size as well as prognosis of patients with AMI after PCI.CMR is considered the gold standard for evaluating cardiac volumes and systolic function13. Unlike previous studies that reported NLR cut-off values that best predicted clinical outcomes, we determined the cut-off value that best predicted large-sized infarction. Therefore, it is not surprising that the cut-off value was lower than reported in previous studies because not all patients who have a large-sized infarction have clinical events. Our cut-off value showed a significant association with poorer clinical outcomes and large-sized infarction.In the current study, we thoroughly compared various pre and post PCI leukocytes profiles and identified that post-PCI NLR showed the best ability to discriminate large-sized infarctions assessed by CMR. To verify prognostic implication of post-PCI NLR, comprehensive assessment was conducted to find relation with post-PCI NLR and various markers of infarct size such as laboratory and echocardiographic findings as well as adverse clinical outcomes. Furthermore, the robustness of these results were supported by many sensitivity analyses such as multivariable regression and IPW adjustment. Thereby our results suggest that post-PCI NLR can be used for predicting prognosis as well as an infarct size predictor in future trials that aim to reduce infarct size. However, this study had several limitations. First, it was a retrospective study. Therefore, there may have been selection bias, and confounding variables may not have been accounted for. To overcome retrospective design of study, multivariable regression and IPW adjustment were performed to minimize the effect of confounders. Second, many patients were excluded from the study because they did not undergo pre- and post-PCI CBC with differential counts. This exclusion could have resulted in selection bias. Third, the number of patients who presented with STEMI was significantly different between the low and high post-PCI NLR groups. However, results from subgroup analysis of STEMI patients only were consistent with the results obtained for the entire study population. Fourth, the post-PCI NLR cut-off value was lower than that reported in previous studiesHigh post-PCI NLR value was associated with higher risk of large-sized infarction as measured by CMR, as well as adverse clinical events in AMI patients who underwent PCI. Our findings suggest that post-PCI NLR, which is an easily measurable and universally available marker, could be a useful tool for risk assessment and prognosis prediction in AMI patients undergoing PCI.Supplementary Appendix


Ivabradine (IVA) is a novel specific HR-lowering agent that acts in sinus atrial node (SAN) cells by selectively inhibiting the pacemaker If current in a dose-dependent manner by slowing the diastolic depolarization slope of SAN cells, and by reducing HR at rest during exercise in humans. Coronary artery diseases (CAD) represent the most common cause of death in middle–aged and older adults in European Countries. Most ischemic episodes are triggered by an increase in HR, that induces an imbalance between myocardial oxygen delivery and consumption. IVA, a selective and specific inhibitor of the If current which reduced HR without adverse hemodynamic effects, has clearly and unequivocally demonstrated its efficacy in the treatment of chronic stable angina pectoris (CSAP) and myocardial ischemia with optimal tolerability profile due to selective interaction with If channels. The aim of this review is to point out the usefulness of IVA in the treatment of ischemic heart disease.Heart rate (HR) is a precisely regulated variable, which plays a critical role in health and disease. Elevated resting HR is a significant predictor of all-cause and cardiovascular mortality in the general population and patients with cardiovascular disease (CVD). β-blocking drugs exert negative effects on regional myocardial blood flow and function when HR reduction is eliminated by atrial pacing; calcium channel antagonists (CCAs) functionally antagonize coronary vasoconstriction mediated through α-adreno-receptors and are thus devoid of this undesired effect, but the compounds are nevertheless negative inotropes. From these observations derives the necessity to find alternative, more selective drugs to reduce HR through inhibition of specific electrical current (I CSAPChronic stable angina pectorisHRHeart rateBPBlood pressureCBFCoronary blood flowCVDCardiovascular diseaseCADCoronary artery diseaseSANSino atrial nodeLVEFLeft ventricular ejection fractionCHFChronic heart failureIVAIvabradineAngina is a chest discomfort caused by myocardial ischemia without necrosis, and is further qualified by its precipitating factors, time course to relief, and clinical characteristics, such as radiation and quality. Typical angina may be triggered by increased activity, emotional stress, cold, wind, and fever . Chronic2 requirements and myocardial O2 supply octa-1,3,5-trien-7-yl)methyl]methylamino}propyl)-1,3,4,5-tetrahydro-7,8-dimethoxy-2H-3-benzazepin-2-one hydrochloride, If in a dose-dependent manner by slowing the diastolic depolarization slope of SAN cells, and reducing HR at rest during exercise in animals and humans ) may decrease IVA exposure and activity. The concomitant use of CYP3A4 inducing medicinal products may require an adjustment of the dose of IVA. The combination of IVA 10 mg twice daily with St John’s Wort was shown to reduce IVA AUC by half. The intake of St John’s Wort should be restricted during the treatment with IVA. Carbamazepine interacts clinically significant with IVA in healthy volunteers, and lowers its bioavailability by about 80% [The concomitant use of potent CYP3A4 inhibitors such as azole antifungals , macrolide antibiotics  ,56 whichIVA at doses of 5.0, 7.5 and 10.0 mg/bid has demonstrated a non-inferior anti-anginal and anti-ischemic effects respect to atenolol (50 or 100 mg/day) in 939 patients with CSAP . In thisf inhibitor ivabradine in patients with coronary disease and left ventricULar dysfunction (BEAUTIFUL) study has demonstrated that in prespecified subgroup of patients with HR of 70 bpm or more (N = 5392), the treatment with IVA was associated with a 36% reduction in relative risk for fatal and non-fatal acute myocardial infarction (AMI) (p = 0.001), a 30% reduction for the need for coronary revascularization (p = 0.016), and a 22% reduction in the hospitalization for fatal and non-fatal AMI or unstable angina (p = 0.023) [The morBidity–mortality EvAlUaTion of the I= 0.023) . This stmore N = 92, the t< 35%, has demonstrated the importance of HR reduction with IVA for improvement of clinical outcomes in heart failure and has confirmed the important role of HR in the pathophysiology of this disorder [The Systolic Heart Failure Treatment with the I(f) Inhibitor Ivabradine Trial (SHIFT), a randomized, double-blind study designed to compare IVA (titrated to a maximum of 7.5 mg twice daily or matching placebo) on outcomes in 6,500 patients with symptomatic chronic heart failure (CHF) (NYHA class II-IV) and LVEF disorder .et al. [versus metoprolol in early phases of anterior ST elevation myocardial infarction (STEMI) reperfused by percutaneous coronary intervention (PCI). In this study 155 patients with a first anterior STEMI, Killip class I–II, an acceptable echocardiographic window, and with an ejection fraction (EF) < 50% 12 h after PCI were randomized to receive metoprolol (76 patients) or IVA (79 patients). The HR was significantly reduced in both groups, but IVA group showed a significant increase in EF. IVA may be administered early (12 h after PCI) to patients with successful PCI for anterior STEMI with an impaired left ventricular function and high HR and sinus rhythm.IVA is presently not indicated in the treatment of AMI and cardiogenic shock. Some studies are published in the literature which investigated the future potentiality of this drug in these two conditions. Fasullo et al.  have invThe major cause of in-hospital AMI mortality remains myocardial failure with consecutive cardiogenic shock and multiorgan failure (MOF). Reduction of HR is one of the most important energy-saving maneuvers, which can be achieved by administration of beta-receptor-blocking agents . OngoingIVA has proved to be of benefit in experimental models with the end points of ischemic myocardial blood flow and contractile function, infarct size, post-infarct remodeling and atherosclerosis. The benefits to ischemic myocardial blood flow and contractile function are strictly heart rate dependent; those on infarct size are partly heart rate independent ,68.HR is a major determinant of myocardial oxygen demand and supply, and increased HR adversely affects the pathophysiology of myocardial ischemia. High resting HR is a risk factor in CVD. The development of the HR lowering agent IVA showed that HR was also an important treatment target, notably in CAD.Indeed, HR reduction with IVA, a selective and specific I(f) inhibitor, reduces myocardial oxygen demand, increases diastolic perfusion time and improves energetics in ischemic myocardium. IVA protects the myocardium during ischemia and reduces remodeling following myocardial infarction. It improves prognosis in patients with CAD, left ventricular dysfunction and HR ≥ 70 beats per minute, as well as in patients with heart failure and left ventricular dysfunction. IVA is selective, safe, well tolerated and can be used in combination with the main drugs for CVD ,69,70.


Cardiac contractility modulation (CCM) is an investigational device-based therapy to enhance ventricular contractility in systolic heart failure patients who are not candidates for cardiac resynchronization therapy (CRT) owing to the absence of wide QRS complexes or who have failed to respond on CRT. The principal mechanism is based on the stimulation of cardiac muscles by nonexcitatory electrical signals to augment the influx of calcium ions into the cardiomyocytes. The majority of patients receiving CCM therapy have concurrent implantable cardioverter defibrillators, and the manufacturer declares both devices can be used in parallel without any interactions. Nevertheless, proper lead positioning of both devices are crucial, and it is mandatory to check device-device interactions during each and every cardiac electronic implantable device-related procedure to prevent adverse outcomes. Cardiac contractility modulation (CCM) can be attained by an investigational device designed to improve the strength of myocardial contractility by delivering nonexcitatory electrical signals to increase calcium ion influx into the cardiomyocytes during the absolute refractory period of the cardiac cycle. The CCM device, Optimizer, is accepted in the United States as an investigational device to treat systolic heart failure patients with narrow QRS complexes or who are nonresponders of cardiac resynchronization therapy (CRT). A CCM unit includes a pulse generator and three pace-sense leads; a sensing lead in the right atrium and two signal-delivering leads implanted at the right ventricular (RV) septum. The manufacturer declares that CCM devices work in parallel with any kinds of implantable cardioverter defibrillator (ICD) system without affecting the ICD function. We present a case in which CCM leads chatter with the ICD lead in the RV which resulted in inappropriate sensing of the CCM signals by the ICD with subsequent delivery of inappropriate shocks.A 72-year-old male with past medical history of myocardial infarction status postpercutaneous coronary intervention, chronic systolic heart failure secondary to ischemic cardiomyopathy, received a single chamber Biotronik implantable cardioverter defibrillator (ICD) with a Medtronic single-coil defibrillator lead (model 6949-65) in 2005. A year later, the patient also received an investigational device, Optimizer III  (model #CCMX8), assembled with St. Jude Medical active fixation pace-sense leads (Model 1388-T), one lead in the right atrium and two in the upper and lower interventricular septum. Prominent electrical signals were identifiable on the patient's surface EKG when CCM was activated.In August 2014, the old Medtronic lead (Model 6949-65) was found to have a sudden increase in RV impedance to >2000 Ohms with “RED” alert warning of the Biotronik device. The particular Medtronic lead was also a subject of a Class-I recall by the Food and Drug Administration. Subsequently, he underwent laser lead extraction and replacement for a new ICD lead, Medtronic Sprint Quattro (Model 6947) dual coil defibrillation lead. The procedure was uneventful. The function of the new ICD system was assessed, and all the device parameters were found within normal limits. Patient's CCM was eight years old at that time and was found no longer functional due to battery depletion. Hence, the device-device interaction with the concurrent CCM unit was not evaluated.In earlier 2015, the patient presented with receipt of six ICD shocks without prior symptoms. Interrogation of the ICD disclosed intermittent, noncyclical, and nonphysiologic noise signals. The intracardiac electrogram recording was shown . All theLead failure was unlikely as all sensing and pacing parameters including lead impendence of the new Medtronic Sprint Quattro lead were normal. The signals  were nonThe patient underwent fluoroscopic examination  on whichThe CCM device along with two St. Jude Medical right ventricular pace-sense leads was extracted, but the same ICD unit was left in place. During the follow-ups over two years, no further noise signals had been detected by his ICD and the patient had not received any more inappropriate shocks.2), Minnesota Living with Heart Failure Questionnaires (MLWHFQ) in narrow QRS systolic heart failure patients despite its lack in mortality benefits or all-cause hospitalizations [Cardiac contractility modulation (CCM) device is designed to enhance ventricular contractility in a subgroup of systolic heart failure patients who are not candidates for cardiac resynchronization therapy (CRT) owing to the absence of wide QRS complexes or who have failed to respond on CRT. Although CCM therapy falls under the investigational category in the United States, it is approved as one of the device-based therapy for heart failure in Europe. CCM therapy can provide a better quality of life and NYHA functional class by improving peak venous oxygen  including ICDs and generally does not cause any interruption with ICD functions. However, functional testing of both Optimizer CCM and ICD systems is crucial and mandated to conduct during every procedure including the time of CCM implantation, an addition or revision of a lead(s) to ensure there is neither oversensing of CCM signals by the ICD nor any device-device interactions. It is important to allow an optimal spacing between the ICD lead and the CCM signal-delivering leads to prevent chattering each other in the RV.To our best knowledge, the consequences of CCM-ICD leads chattering as an outcome of inappropriate delivery of ICD shocks which even warranted the extraction of the CCM device have never been reported. In our case, CCM and the old ICD units were working in parallel without any interactions until the ICD lead was replaced. The diagnosis was challenging since signals were similar to those of ICD lead dysfunction but the leads parameters were normal. Under fluoroscopic examination, it was found that all the leads were implanted 1-2 cm apart as recommended by the manufacturer. However, there was the excessive redundancy of some of the leads, and it was believed to be the etiology of leads chattering and oversensing by the ICD. Our case gives us a valuable lesson regarding the crucial role of CCM-ICD leads positioning and mandatory testing of device-device interactions during each and every CEID procedure.Optimizer is an investigational device based on the concept of cardiac contractility modulation. It is designed to improve myocardial contractility without increasing cardiac oxygen consumption by facilitating the calcium handling of cardiomyocytes. The device has a potential to fill up the present therapeutic gap in the treatment of systolic heart failure patients who have narrow QRS complexes or failed to CRT. The majority of patients receiving CCM therapy have concurrent ICD and the manufacturer declared both devices can be used in parallel without any interaction in between. Nevertheless, proper leads positioning of both devices are crucial, and it is mandatory to check device-device interactions during each and every CEID procedure to prevent adverse outcomes.


Background: Heart failure with preserved ejection fraction (HFpEF) is characterized by heart failure symptoms and structural change (including fibrosis). The relationship between novel biomarkers and the above components remains unclear. Methods: Seventy-seven HFpEF patients were recruited. All patients underwent echocardiography with tissue doppler imaging, cardiac magnetic resonance imaging (CMRI), and measurement of plasma inflammatory, remodelling, endothelial function, and heart failure biomarker levels. Myocardial fibrosis was defined by CMRI-extracellular volume. Forward conditional logistic regression was applied to demonstrate the determinants of myocardial fibrosis or heart failure symptoms. Results: The levels of growth differentiation factor, tissue inhibitor of metalloproteinase (TIMP)-1, galectin-3, and N-terminal pro b-type natriuretic peptide (NT-proBNP) were significantly higher in patients with more myocardial fibrosis. Matrix metalloproteinase-2 (MMP-2) and galectin-3 were independent markers of ECV. After adjusting for confounding factors, plasma galectin-3 and MMP-2 levels were correlated with myocardial fibrosis levels (odds ratio (OR): 1.05, 95% confidence interval (CI): 1.02 to 1.09, p = 0.005 and OR: 2.11, 95% CI: 1.35–3.28, respectively), while NT-proBNP level only was associated with heart failure symptoms. We developed a score system consisted of biomarkers and clinical parameters. The area under the curve of the scoring system receiver operating characteristic curve is 0.838 to predict the degree of myocardial diffuse fibrosis. Conclusions: In conclusion, we found that galectin-3 and MMP-2 were significantly associated with global cardiac fibrosis in HFpEF patients. We also combined plasma biomarkers and clinical data to identify HFpEF patients with more severe cardiac fibrosis. In recent years, population-based studies have indicated that the prevalence of heart failure with preserved ejection fraction (HFpEF) has been increasing . The morAlthough previous studies have shown that plasma biomarkers that reflect changes in extracellular matrix fibrillar collagen synthesis and degradation may predict the presence of HFpEF  and thatOwing to the importance of evaluating the extent of global cardiac fibrosis by non-invasive methods, several studies have focused on post-contrast cardiac magnetic resonance imaging (CMRI) myocardial T1 time as the gold standard to quantify diffuse myocardial fibrosis in patients with cardiomyopathies . NeverthWe aimed to examine a variety of novel fibrosis and inflammatory biomarkers that has been proposed recently ,8 in pat2 or left ventricular mass index > 122 g/m2 in female, >149 g/m2 in male. (4) 15 > E/e’ > 8 and NT-proBNP > 220 pg/mL. Signs or symptoms of congestive heart failure include lung crepitations, pulmonary oedema, ankle swelling, hepatomegaly, dyspnoea on exertion, and fatigue. Significant hepatic disease, secondary hypertension, pericardial disease, severe valvular heart disease, cancer, and chronic obstructive pulmonary disease were excluded [The study group consisted of patients with heart failure admitted to the cardiovascular ward or outpatient clinics of the National Taiwan University Hospital from December 2011 to October 2015. Patients with a diagnosis of HFpEF (as defined in previous reports as well as by the 2007 consensus statement of the European Society of Cardiology) were enrolled from the TDHFR . In brieexcluded ,14. All g for 15 min, and then the plasma was separated and stored at −80 °C until use.All blood samples were collected from each patient after 12 h of fasting. Biomarkers that were reported to be associated with HFpEF were examined. The blood was spun at 2000× Levels of plasma inflammatory markers , interleukin-1 beta , interleukin-6 , C-reactive protein , growth differentiation factor (GDF-15)  and osteopontin-A ), remodelling markers  , tissue inhibitor of metalloproteinase-2 (TIMP2) , matrix metalloproteinase-2 (MMP-2) , matrix metalloproteinase-9 , procollagen type I , galectin-3  and connective tissue growth factor (CTGF) ), endothelial function markers (endothelin-1) , and heart failure markers (suppression of tumorigenicity-2 (ST2)  and N-terminal of the prohormone brain natriuretic peptide (NT-proBNP) ) were measured with high-sensitivity enzyme-linked immunosorbent assays.Left atrial (LA) diameter, left ventricular (LV) end diastolic diameter, systolic diameter, interventricular septum thickness, LV posterior wall thickness, mitral inflow early rapid filling wave (E), peak velocity of the late filling wave due to atrial contraction (A), E/A ratio, E wave deceleration time, and mitral annular early diastolic velocity were measured according to the American Society of Echocardiography’s guidelines by using an iE33 xMATRIX echocardiography system . The peak annular early and late diastolic velocities of the lateral mitral annulus in tissue Doppler imaging (e’ and a’) were also recorded. Doppler and colour Doppler studies were performed to detect valvular heart disease. Significant valvular heart disease was defined as at least moderate aortic or mitral stenosis/regurgitation.MRI was performed on a 3-T MRI system  with an 8-channel cardiovascular phased array torso coil. Myocardial T1 mapping was performed with an electrocardiography (ECG)-triggered Modified Look Locker Inversion recovery (MOLLI) sequence before and 10 min after a 0.15 mmol/kg intravenous administration of the gadolinium-based contrast agent . The MOLLI protocol used two Look-Locker cycles to acquire seven images over 11 heart beats, and the scanning parameters were: TR/TE, 1.9 ms/1.0 ms; flip angle, 35°; minimum inversion time, 110 ms; inversion time increment, 80 ms; matrix size, 256 × 192; slice thickness, 6 mm; spatial resolution, 1.28 mm; GRAPPA acceleration factor, 2; number of inversions, 2; images acquired after first inversion, 5; pause 4 heart beats and images acquired after second inversion, 2. Five evenly spaced short-axis slices were acquired sequentially from the LV base to apex. After post-contrast T1 acquisition, late gadoninium enhancement (LGE) images were acquired using an ECG-triggered phase-sensitive inversion recovery prepared segmented fast gradient echo pulse sequence [Cine MRI was performed using a segmented balanced steady-state gradient echo pulse sequence with a retrospective ECG R-wave trigger. The scanning parameters were: TR/TE, 3.0 ms/1.5 ms; flip angle, 46°; matrix size, 256 × 208 and spatial resolution, 1.21 mm. Multiple short-axis slices were obtained from the mitral orifice to the LV apex with a slice thickness of 8 mm and a gap of 2 mm. The true temporal resolution was 63 ms, and 30 cardiac phases were reconstructed retrospectively for each slice level.Quantitative analysis of myocardial ECV was performed on T1 maps . The regFor LV function and mass analysis, endocardial and epicardial contours of the LV were determined at each slice level on cine MRI and the area enclosed by each contour was computed . LV volut test and Mann–Whitney U test respectively while comparisons between categorical variables made using Pearson’s chi-square test. Multiple logistic regression modelling was applied followed by a forward stepwise analysis method to determine the factors associated with two outcomes CMRI fibrosis (ECV < 28% vs. ≥28%) and clinical heart failure. Factors including all the baselines, MRI, and laboratory parameters listed in p-value < 0.05 was considered statistically significant.Data were analysed using SPSS 15.0 software . The normality of continuous variables was tested by Kolmogorov–Smirnov test. Since we found that most of the serum cytokine levels were not normally distributed, all the serum cytokine levels were expressed by median plus quartiles (25–75%). Variables with normal distribution were represented as mean values ± standard deviation, while categorical variables were represented as frequencies. Comparisons between continuous data with and without normal distribution were performed by using the Student’s A total of 77 patients with diastolic dysfunction were included in the study cohort. The baseline characteristics according to fibrosis  severity are shown in p = 0.018)  ng/mL vs. low-ECV, 6.81 (5.59–8.67) ng/mL; p < 0.001). In addition, levels of NT-proBNP, the well-known heart failure marker, were also higher in the high-ECV group  pg/mL; low-ECV, 850.0 (439.5–1335.0); p = 0.021).Inflammatory, remodelling, endothelial, and heart failure markers were all examined. The detailed results of cytokines in each group were shown in = 0.018) . Remodelp = 0.005 and OR: 2.11, 95% CI: 1.35–3.28, respectively)), whereas endothelin-1 had a borderline relationship with the development of higher cardiac fibrosis . For the determinants of aggravated heart failure, we performed another forward stepwise analysis and found that TIMP1 and NT-proBNP were the major determinants for the presence of aggravated heart failure .The correlations among ECV and CMRI diastolic and systolic function parameters and biomarkers were assessed. We then applied a forward stepwise analysis method to determine the factors associated with ECV. The results are demonstrated in We created a scoring system by using diabetes mellitus status  and the median levels of MMP-2 (2 vs. 0), galectin-3 (1 vs. 0) and endothelin-1 (2 vs. 0), as cut-off points. The results of this scoring system are presented in In the current study, we evaluated all patients with HFpEF by using CMRI and determined the global absolute cardiac fibrosis value. We were able to identify the extent of fibrosis in each patient with HFpEF and measured a variety of inflammation, cardiac remodelling, endothelial function, and heart failure cytokine levels. We found that galectin-3 and MMP-2 were significantly associated with global cardiac fibrosis, even after adjusting for confounding risk factors, whereas TIMP2 and NT-proBNP were significantly associated with the aggravation of heart failure symptoms. We also developed a cytokine model along with inclusion of clinical parameters to identify HFpEF patients with more severe cardiac fibrosis. To the best of our knowledge, this is the first report to demonstrate and differentiate the relationship between a variety of cytokines and cardiac ECV (fibrosis content) or heart failure symptoms in a prospective HFpEF cohort. With our models, a clinical physician could decide the level of fibrosis and actual severity of HFpEF patients by blood tests and clinical history.We found that NT-proBNP level was unable to differentiate the degree of fibrosis well, and that it was significantly associated with heart failure symptoms. One possible explanation for this is that NT-proBNP is a marker of volume overload rather than of cardiac dysfunction . PreviouWe calculated the degree of diffuse cardiac fibrosis by CMRI-ECV, which should not be affected by confounding factors such as magnetic field, acquisition timing, the amount of contrast injected, and the renal function of patients. CMRI-ECV has been shown to be stable over a wide time range after contrast administration . GalectiVarious studies have assessed biomarkers and HFpEF. Most studies examined single biomarkers or groups of similar biomarkers, and thus the results were often inconsistent. A recent study included a group of patients with HFpEF from the PARAMOUNT trial and compared the predictive value of four biomarkers . The authors concluded that in patients with HFpEF, the levels of biomarkers that reflect collagen homeostasis were correlated with the severity of disease and underlying pathophysiology and may modify the structural response to treatment . The mosTo summarize the results from numerous studies and a review article, myocardial fibrosis could be resulted from multiple pathways and unlike most previous studies ,40, we eThe present study had several limitations. First, this was a cross-sectional study, and the number of patients included was small. Further large-scale studies are warranted to determine the prognostic value cytokine levels in patients with HFpEF. Second, the findings were purely correlative, and are not sufficient to indicate any causative relationships. Third, we did not directly measure tissue biomarker expression in patients with HFpEF. Theoretically, this is not feasible in human studies. However, we successfully measured the severity of tissue fibrosis by using CMRI-ECV and confirmed the presence of correlations between various novel cytokines and fibrosis or heart failure symptoms. We believe that CMRI-ECV is the most reliable non-invasive method for elucidating the relationships between cytokines and tissue or clinical expression.In conclusion, we successfully studied the associations between plasma biomarkers with myocardial fibrosis or heart failure symptoms in a cohort of HFpEF patients. We found a significant correlation among plasma NT-proBNP, TIMP, and the development of heart failure symptoms. We also demonstrated that galectin-3 and MMP-2 levels increased according to the severity of myocardial fibrosis after adjusting for confounding factors. The results of this study indicated that different biomarkers could be important intermediaries in promoting further fibrosis and/or inflammatory cascades, or may reflect the elevation of cardiac diastolic filling pressure. While there is little information available regarding the medical management of HFpEF, novel therapies that downregulate the expression of these biomarkers may represent a new direction. Through examination of cytokine levels, the status, aetiology, or severity of cardiac fibrosis and LV diastolic dysfunction can be determined. This may allow more individualized therapies to be developed in the future.


Tricuspid regurgitation (TR) may affect as much as 65–85% of the population with the prevalence of moderate-to-severe TR in the United States reported at greater than 1.6 million. However, only 8,000 tricuspid valve operations are performed annually in the United States. As severe TR is associated with poor outcomes, there is an unmet clinical need for surgical or percutaneous transcatheter based treatment of TR. Over the last two decades there have been significant developments in percutaneous transcatheter based therapies for valvular disease. However, this progress has not been mirrored for the tricuspid valve until recently; we are now at a cross-roads of new transcatheter devices becoming available for treatment of TR. In this review, we discuss the principles of performing transcatheter tricuspid valve replacement, analyze the devices that can be utilized and outline the challenges related to this procedure. Tricuspid regurgitation (TR) is a commonly encountered manifestation of valvular heart disease, it may affect as much as 65–85% of the population , 2. The The prevalence of moderate-to-severe TR in the United States has been reported at greater than 1. 6 million. Despite this only 8,000 TV operations are performed annually in the United States . FurtherThe development of devices specifically designed for percutaneous TV repair or replacement are currently at an early stage. In this section, we will analyze the main challenges of TTVR procedures, in order to become a safe and effective alternative to medical therapy or high-risk surgical interventions.The TV apparatus is a complex structure consisting of 3 leaflets  that are inserted to the tricuspid annulus and attached through the chordae tendinae to the papillary muscles of the right ventricle (RV). The tricuspid annulus is relatively less fibrous when compared with the mitral valve and the right coronary artery surrounds the parietal attachment of the valve. The normal physiological valve is a dynamic, nonplanar structure that varies in size and shape throughout the cardiac cycle .This anatomical and functional complexity reflects on different procedural issues that must be taken in account during the development of tricuspid prosthesis and relative delivery systems Figure :Access selection: One of the main anatomical challenges for current generation TTVR devices is the dimensions of the TV annulus; the TV annulus is large  and it gets even larger when longstanding FTR and RV dilation are present. Hence, prosthetic TV valves have a large profile requiring large caliber sheaths. Large bore venous access  is of paramount importance when planning a replacement procedure and led to the preferential selection of three potential sites, that have potential advantages and disadvantages  node lies in the muscular portion of the atrio-ventricular septum, near the ostium of the coronary sinus (at the apex of the triangle of Koch). The bundle of His is a direct continuation of the AV node and it passes through the right trigone of the central fibrous body to reach the ventricular septum. This area is near to the commissure between septal and anterior tricuspid leaflets . Surgical TV repair is seldom performed for isolated TV disease  . FurtherTTVR may be preferred over repair techniques in those patients in where mechanism of TR is not functional. Fibrotic leaflets (as a result of carcinoid syndrome or of rheumatic disease) or large leaflet prolapse may be suitable of TTVR over repair.On the other hand, patients with extremely dilated annuli and/or with extreme leaflet tethering have low probability to be successfully treated with currently available repair devices unless annular and leaflet devices are combined. In these patients, tricuspid valve replacement may be the first option in order to offer the best result.Lastly, a fundamental aspect is pre-procedural evaluation of pulmonary hemodynamics and RV function: despite the lack of evidence, we can hypothesize that an acute reduction in TR in patients with severe RV dysfunction and severe pulmonary hypertension may result in acute afterload mismatch despite technical and procedural success . VentricSimilar to mitral valve procedures, integration of interventional and imaging techniques is essential for TTVR. Cardiac imaging is essential at three crucial points: Pre-procedural planning , interventional guidance, and follow-up after the procedure. The main imaging modalities are echocardiography  and of the RV.Echocardiography plays a major role, allowing complete assessment of the TV as well as RV pathophysiology. Since the TV is the most anterior structure of the heart, transthoracic 2D and 3D are fundamental and usually offer good imaging due to low thoracic impedance. It allows good evaluation of TR severity and etiology, as well as RV function and pulmonary pressure. Transesophageal echo (TEE), especially with full 3D sets, may help defining the mechanism of TR and morphologically characterize the TV: detailed assessment of tricuspid leaflet morphology and function can be obtained, as well as TV annulus dimensions and function.Computed tomography imaging, with multiplanar 3-dimensional reconstruction, is essential for preprocedural TV structural evaluation. It allows precise measurement of the RV dimensions and TV annulus size, relation with right coronary artery and the distance between the TV annulus and RV apex. In addition, CT enables preprocedural fluoroscopic angulation calculation and assessment of the access site dimensions and course (e.g. subclavian and axillary veins) for TTVR . HoweverCardiac magnetic resonance imaging can be utilized as adjunctive imaging modality for TV assessment prior to TTVR. It can be used for anatomical and functional assessment due to its excellent spatial resolution. CMR imaging with dedicated RV planes provides detailed RV chamber evaluation that is comparable to 3-dimensional echocardiography; however unlike echocardiography it is not hampered by patient's body habitus or lung fields. In addition, for patients with atrial tachycardias or fibrillation, free-breathing CMR sequencing is effective in providing quantitative evaluation. CMR evaluation of TV leaflet morphology can be challenging because of the thin nature of the leaflets. Evaluation of the TV annulus can be performed using breath-held cine using multiple long-axis views. Moreover, offline multiplane reconstruction can be performed to get detailed anatomical evaluation of the TV annulus. Lastly, severity of TR can be calculated using indirect quantification (difference between the planimetered RV stroke volume and forward pulmonic flow volume) .Multimodality imaging is essential for percutaneous TV interventions. Identification of TV annulus, for instance, can be performed with echocardiography but a guidewire placed into right coronary artery may be a useful angiographic marker. Due to its anterior location, the TV is not always well visualized with TEE; however, this remains the first-choice procedural imaging modality. When in doubt, transthoracic echo may be useful. The role of intracardiac echocardiography is not clear yet, but it may overcome the limitations of TEE and may be useful in ensuring coaxial alignment of the valved-stent to the TV annulus before deployment .Once again, echocardiography has a key role in evaluation of procedural outcome. Echocardiography is able to evaluate not only the entity of regurgitation after TTVR that may be related to paravalvular or intravalvular jets, but also (and more importantly) the consequences of the insufficiency: RV reverse remodeling, regression of right atrial volume and inferior vena cava size may be used as surrogate endpoints of the success of the procedure . Postprocedural CT evaluation may be useful if there is uncertainty at follow-up echocardiography with regards to complications  . The rolPre-procedural echocardiographic assessment including TEE and CT imaging evaluation are fundamental. Echocardiography enables hemodynamic and anatomical TV evaluation, and CT imaging permits precise device sizing and estimation of fluoroscopic angulations for the procedure. Intra-procedurally, fusion imaging (echocardiography and fluoroscopy) facilitates improved understanding of anatomical structures while showing enhanced visualization of catheter and device movements. In particular, it has a role in patients where technical difficulty is encountered and during initial learning curve implanting TTVR. Furthermore, in cases with poor transthoracic and transesophageal window we have found intra-cardiac echocardiography particularly helpful. It can be helpful for navigation inside right heart chambers, to visualize the device, to guide their fine positioning and orientation , and to discern the annulus from the leaflets.While many companies are working on percutaneous tricuspid valve replacement devices, currently only a few have been successfully implanted in humans and there are a number of devices in development. The following section provides a brief overview of these devices.NaviGate stent-valve  is a dedicated atrioventricular valve for the treatment of mitral and tricuspid regurgitation. It is a novel self-expanding valved-stent designed to treat functional tricuspid regurgitation and is available in sizes from 36 to 52 mm Figure . It consInitial pre-clinical feasibility studies demonstrated that the NaviGate is safe and feasible, and results in a secure and stable engagement of the native annulus, with excellent hemodynamic and valve performance. There have been 27 cases of first-in-human successful implantation of the NaviGate prosthesis using the transjugular and transatrial approaches. The device size implanted were 36mm in 5%, 40mm in 5%, 44mm in 27%, 48mm in 27%, and 52mm in 36% of patients. Implantation of the NaviGate TTVR resulted in TR severity reduction from severe/torrential in all patients to ≤2+ in all patients, 78% having none/trivial postprocedurally.An important consideration is that device oversizing by 5–10% to the TV annulus or prior TV ring size to achieve better seal . To dateThe Trisol valve  is a novel percutaneous transcatheter valve representing a new concept in the treatment of severe TR Figure . The TriThe LUX-valve is a Chinese designed and manufactured self-expanding prosthesis made from bovine pericardial tissue mounted on a nitinol stent frame Figure . It is iTricuspid regurgitation is a common condition in the general population and when of moderate-to-severe is associated with poor clinical outcomes. There is an unmet clinical need for intervention in these patients. Tricuspid valve replacement is an alternative therapeutic option for these patients. We are currently at an early stage of TTVR therapies for TR and expect this field to mature significantly in the next few years. Clinical studies with new TTVR devices will enable us to elucidate which patient population will benefit the most from TTVR.OD, DR, GW, amd AL conception and design or analysis and interpretation of data, or both; OD, DR, AM, MA, SM, GW, AC, and AL: drafting of the manuscript or revising it critically for important intellectual content; OD and AL final approval of the submitted manuscript.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The reviewer PD declared a shared affiliation, with no collaboration, with one of the authors, AL, to the handling editor at time of review.


In patients with Noonan syndrome (NS), cardiac disorders such as pulmonary valve stenosis (PS) or hypertrophic cardiomyopathy (HCM) are common. While some patients can develop heart failure associated with HCM, the long-term outcome of adult patients with NS is reported to be good. Fatal outcomes of heart failure in patients with NS but without HCM are rare.We report a 25-year-old Japanese woman diagnosed with NS in adulthood. She exhibited short stature and minor facial dysmorphism and was diagnosed with PS at 1 year of age. After surgical valvuloplasty for PS at 6 years of age, her general condition became stable without specific medical treatment. She discontinued regular medical follow-up for PS. At 21 years of age, she developed acute decompensated heart failure, which was mainly right-sided heart failure due to severe pulmonary regurgitation (PR) and tricuspid regurgitation (TR). There was no evidence of HCM or PS recurrence. On the basis of the history of PS and characteristic physical features including short stature, webbed neck, and hypertelorism, she was clinically diagnosed with NS. At 25 years of age, she developed heart failure of both sides due to PR, TR and late-onset severe mitral stenosis (MS). The etiology of MS was uncertain. Owing to the patient’s condition, surgical options were considered to be extremely high risk. She was treated with optimal medical treatment as well as the occasional abdominal cavity drainage for recurrent ascites; however, she died of decompensated heart failure at 27 years of age.We describe an adult patient with NS without HCM who died of heart failure caused by severe PR, TR and MS. Clinicians should recognize that ongoing or late-onset cardiac disorders can develop in patients with NS, and lead to fatal heart failure. Optimal medical follow-up to monitor cardiac function and early identification of heart failure are important.The online version of this article (10.1186/s12872-018-0878-1) contains supplementary material, which is available to authorized users. Noonan syndrome (NS) is a common genetic disorder with multiple congenital abnormalities, such as short stature, congenital heart disease, renal anomalies, lymphatic malformations, and characteristic facial features –3. Cardi2, and a normal estimated mitral valve area of 4.13 cm2/m2. On the basis of the history of PS and characteristic physical features including short stature, webbed neck, and hypertelorism, she was clinically diagnosed with NS for the first time. A chromosomal study showed 46XX with no abnormality of chromosome 12. The patient refused genetic testing. She was successfully treated with a loop diuretic, beta-blocker, angiotensin-converting enzyme inhibitor, and aldosterone inhibitor. After discharge, she resumed regular follow-up at the local hospital. Although the symptoms of heart failure, such as dyspnea and edema, persisted with a New York Heart Association class of II these symptoms could be controlled with oral medical treatment. There were no records regarding the follow-up echocardiographic findings at the local hospital. At 25 years of age, she was admitted to the local hospital again for massive ascites and marked edema and was referred to our hospital. Her height was 107 cm and her weight was 33 kg. She had a body temperature of 36.8 °C, blood pressure of 90/50 mmHg, regular pulse rate of 125 beats/min, respiratory rate of 18 breaths/min, and oxygen saturation of 95% without oxygen administration. On physical examination, she exhibited jugular venous distention at her neck, and systolic and diastolic regurgitant murmur at the left sternal border. Her breath sounds were decreased, and she had abdominal distention with no tenderness and significant leg edema. Laboratory data upon hospitalization are shown in Table 2, and confirmed severe MS with an estimated mitral valve area of 0.81 cm2/m2. Coronary arteries were intact. There was no evidence of rheumatic change or infectious endocarditis; the etiology of the late-onset MS was uncertain. Computed tomography of the chest and abdomen showed massive ascites as well as plural effusion and atelectasis in the right lung. On the basis of these findings, she was diagnosed with heart failure of both sides, which was mainly caused by severe PR and TR after surgical valvuloplasty for PS as well as the late-onset severe MS with uncertain etiology. Moreover, her abdominal ultrasonogram findings, including irregular external contour, enlarged left liver lobe, and splenomegaly, indicated that she had developed cirrhosis. This was thought to be associated with long-standing right-side heart failure, because of the negative viral or other hepatitis screening. Results of the analysis of ascites and plural effusion were consistent with a pure transudate. Thus, excessive fluid of the chest and abdomen was considered to have been caused by the chronic right-side heart failure in addition to the severe hypoalbuminemia associated with advanced cirrhosis and protein-losing enteropathy. In addition to the abdominal and chest drainage, fluid management using furosemide, tolvaptan, and carperitide was successfully performed. We discussed a treatment strategy with surgeons, including mitral valve replacement, tricuspid valvuloplasty, and right ventricular outflow tract reconstruction; however, considering the patient’s low left ventricular function, cirrhosis, very low albumin level, and atelectasis caused by the long-standing pleural effusion, surgical options were considered to be extremely high risk. In addition, transcatheter cardiac intervention could not be performed in Japan at that time. Therefore, we continued the optimal medication treatment as well as the occasional abdominal cavity drainage for recurrent ascites. Unfortunately, after repeated hospitalizations for ascites and edema, she died of decompensated heart failure 2 years later.The patient was born at 39 weeks of gestation and delivered by Cesarean section due to polyhydramnios. She was 3295 g at birth. Although short stature and abnormal facial features such as depressed nose, deeply grooved philtrum, and macroglossia were recognized at birth, the signs were not associated with any particular diagnosis. At 1 year of age, she was diagnosed with pulmonary valve stenosis. At 5 years of age, a balloon valvuloplasty for severe PS was performed; however, it was not sufficient to reduce the pressure gradient of PS (from 80 mmHg to 50 mmHg). At 6 years of age, surgical valvuloplasty to enlarge the annulus and reconstruct the right ventricular outflow tract was performed, which resulted in the disappearance of the PS pressure gradient. She was followed-up at our hospital yearly. Although echocardiogram showed mild PR, her clinical condition was good without specific medical treatment. When she was a high school student, she discontinued regular medical follow-up, and started studying abroad at 18 years of age. She occasionally experienced transient leg edema during this time. At 21 years of age, she developed dyspnea, edema, and abdominal bloating. She returned to Japan; thereafter, she required an emergency hospitalization. She was diagnosed with acute decompensated heart failure, which was mainly right-sided heart failure due to severe PR and TR. It was thought that PR had been subclinically exacerbated after the surgical valvuloplasty, resulting in right-ventricular volume overload. She was also diagnosed with protein-losing enteropathy associated with abnormalities in lymphatic drainage. Echocardiography showed no evidence of HCM, MS, or PS recurrence. Cardiac catheterization revealed a normal cardiac index of 3.9 L/min/mAdditional file 1: Video 1. Echocardiogram in the parasternal long axis view showing enlargement of the right-side heart and the thickening of the mitral valve leaflets. (MP4 768 kb)Additional file 2: Video 2. Echocardiogram in the short-axis view showing displacement of the ventricular septal wall due to the enlarged right-side heart. (MP4 735 kb)Additional file 3: Video 3. Color Doppler echocardiogram in the short-axis view at the aortic valve level showing severe pulmonary regurgitation. (MP4 790 kb)Additional file 4: Video 4. Color Doppler echocardiogram in the apical view showing severe tricuspid regurgitation. (MP4 770 kb)We encountered a fatal case of heart failure, which was caused by severe PR and TR after surgical valvuloplasty for PS, and late-onset severe MS, in an adult patient with NS. Our experience revealed two important clinical issues. Ongoing or late-onset cardiac disorders can develop in patients with NS and lead to fatal heart failure. Optimal medical follow-up to monitor cardiac function and early identification of heart failure are important to facilitate the appropriate management and treatment of patients with NS.Ongoing or late-onset cardiac disorders can develop in patients with NS, and lead to fatal heart failure. The most common cardiac abnormalities associated with NS are PS 50–60%) and HCM (20%) –6. The e0% and HCOptimal medical follow-up to monitor cardiac function and the early identification of heart failure are important to facilitate the appropriate management and treatment of patients with NS. Approximately one-third of patients with NS and PS require therapeutic interventions, such as percutaneous balloon valvuloplasty or open surgical valvuloplasty . AlthougAs the recent innovation in radical surgery for congenital heart disease has shown high success and high survival rates in neonatal patients, the number of cases of adults with congenital heart disease are increasing. However, the long-term results of many types of radical surgery for congenital heart disease remain unclear. Thus, long-term follow-up of patients with congenital heart disease, including patients with NS, has become increasingly important. Optimal medical follow-up should be conducted for all post-operative patients with congenital heart disease, even for those in good clinical condition.In conclusion, we describe an adult patient with NS without HCM who had heart failure in both sides that was caused by severe PR and TR after surgical valvuloplasty for PS, and late-onset severe MS. Clinicians should recognize that ongoing or late-onset cardiac disorders can develop in these patients, leading to fatal heart failure, even in the absence of HCM. Optimal medical follow-up to monitor cardiac function and the early identification of heart failure are thus crucial.


To detect diffuse myocardial fibrosis in different severity levels of left ventricular diastolic dysfunction (DD) in spontaneous type 2 diabetes mellitus (T2DM) rhesus monkeys.Eighteen spontaneous T2DM and nine healthy monkeys were studied. Echocardiography was performed for diastolic function classification. Cardiac magnetic resonance (CMR) imaging was performed to obtain extracellular volume fraction (ECV) maps and T1ρ maps at two different spin-locking frequencies. ECV values, T1ρ values, and myocardial fibrosis index (mFI) values which are based on the dispersion of T1ρ, were calculated. Global peak diastolic longitudinal strain rates (GSrL) were also obtained.Echocardiography results showed mild DD in nine T2DM monkeys and moderate DD in the other nine. The global ECV values were significantly different among healthy animals as compared with animals with mild DD or moderate DD, and the ECV values of animals with moderate DD were significantly higher as compared with those of mild DD. The mFI values increased progressively from healthy animals to those with mild DD and then to those with moderate DD. Diastolic function indicators  correlated well with ECV and mFI.Monkeys with T2DM exhibit increased ECV, T1ρ, and mFI values, which may be indicative of the expansion of extracellular volume and the deposition of excessive collagen. T1ρ mapping may have the potential to be used for diffuse myocardial fibrosis assessment.Monkeys with T2DM exhibit increased ECV, T1ρ, and mFI values, which may be indicative of the expansion of extracellular volume and the deposition of excessive collagen.• The relationship between diastolic dysfunction and diffuse myocardial fibrosis may be demonstrated by imaging markers.• Non-contrast T1ρ mapping may have the potential to be used for diffuse myocardial assessment.• The online version of this article (10.1007/s00330-018-5950-9) contains supplementary material, which is available to authorized users. Diabetes leads to abnormalities in cardiac relaxation that predominantly results in heart failure with preserved ejection fraction (HFpEF) . The numnative T1ρ mapping has been used for myocardial fibrosis detection [Cardiac magnetic resonance (CMR) T1 mapping has been used for the assessment of diffuse myocardial fibrosis. However, post-contrast T1 mapping is affected by the agent dose, the measurement timing, and the renal clearance rate. Although native T1 has recently emerged as a non-contrast imaging technique for the assessment of myocardial fibrosis , 8, the etection , 11. In etection . In addietection , 14. Theetection .Rhesus monkeys with spontaneous type 2 diabetes mellitus (T2DM) demonstrated manifestations that are highly similar to those of human beings . This anIn this initial study, rhesus monkeys with T2DM and varying degrees of DD were used for diffuse myocardial fibrosis detection. We used ECV as an imaging marker to determine diffuse myocardial fibrosis content. In addition, the potential of non-contrast T1ρ mapping for the assessment of diffuse myocardial fibrosis was also explored.Eighteen rhesus monkeys with spontaneous T2DM  and nine healthy control (HC) rhesus monkeys matched for gender, age, and weight were studied. The criteria used for rhesus monkey selection were guided by our previous work  and requThe general condition and related blood biochemical indicators of all monkeys are shown in Table Transthoracic echocardiography was performed using a standard protocol  with theIn accordance with the classification of DD in our previous study and in humans , 21, monCMR imaging was performed using a 3.0 Tesla magnetic resonance imaging system  with a 32-channel cardiac surface coil (Siemens).A CMR cine sequence was performed to scan 10 to 14 short-axis slices via a steady-state free precession with retrospective electrocardiogram triggering. Next, the T1ρ images were obtained using an electrocardiogram-gated T1ρ-prepared gradient echo sequence in three short-axis slices at the base, middle, and apex of the left ventricle. A modified look-locker inversion recovery (MOLLI) sequence with motion correction was then applied to obtain pre-contrast T1 maps with an acquisition scheme of 5(3)3 , 23. Ten42© software (Circle Cardiovascular Imaging Inc.). The following parameters were obtained: left ventricular end-systolic volume (LVESV), left ventricular end-diastolic volume (LVEDV), stroke volume (SV), left ventricular ejection fraction (LVEF), left ventricular (LV) mass, and average heart rate (a-HR). Based on the cine sequence, we also performed strain analysis using cmr42©-based feature tracking. Both the global peak systolic longitudinal strain (GSL) and the global peak diastolic longitudinal strain rate (GSrL) were obtained. Based on the pre-contrast and post-contrast T1 maps, which were automatically generated with a prototype inline process function from Siemens, ECV maps were generated by cmr42©. If there was motion between the pre- and post-T1 series, the pre- and post-MOLLI were registered using a cmr42© intensity-based registration method then ECV maps were calculated. The myocardial fibrosis index (mFI) was calculated as follows:ω1 = γB1 and γ is the gyromagnetic ratio. The T1ρ(0) value is relatively constant for myocardial tissue with different quantities of fibrosis. Although the mFI is calculated in millisecond, it was used as an index that had been calculated in arbitrary units for the purposes of this study. All of the image processing and analyses were performed with a custom-written software , which was created in MATLAB (MathWorks). Segmental [All CMR images were prospectively analyzed. A blood sample was taken from all monkeys immediately before each CMR study for hematocrit measurements. Cine and ECV mapping were analyzed offline with cmregmental  ECV valuOne diabetic monkey was given deep anesthesia  to euthanasia. Histologic slices from the anterior interventricular septum were excised. After dehydration and embedding, the slices were subjected to the Masson staining protocol and analyzed under an optical microscope .H test was used to analyze non-normal distribution; the Dunn-Bonferroni test was used in post hoc analysis. Bivariate correlations were performed using either the Pearson or Spearman method, as appropriate. Significance was assumed at p < 0.05.Statistical analysis was performed using SPSS version 22 (IBM). All data were checked for normality using the Shapiro-Wilk test and presented as the mean ± standard deviation and mean ) or as a median (Q1–Q3), as appropriate. Normally distributed data sets were analyzed with one-way analysis of variance, and Fisher’s least significant difference test and Student-Newman-Keuls test were used in post hoc analysis. The Kruskal-Wallis There were nine T2DM monkeys with mild DD in group 2 and nine T2DM monkeys with moderate DD in group 3. The nine HC monkeys in group 1 demonstrated normal DD , and the ECV values of group 3 were significantly higher as compared with those of group 2 (p = 0.027). However, there was no significant difference in ECV values between group 1 and group 2 (p = 0.307) . The differences between group 1 and group 2 (p = 0.049) and between group 2 and group 3 (p = 0.007) were all significant. GSrL values in group 3 were significantly lower than those of group 1 (p = 0.013). The results of the post hoc analysis are shown in Supplemental Table The baseline CMR results summarized in Table r = 0.603) .There was a moderate positive correlation between ECV and mFI r = 0.60 r = − 0.421) and ECV (r = − 0.607). GSL was found to be correlated with ECV (r = − 0.434). E’ was correlated with mFI (r = − 0.465), T1ρ (r = − 0.549), and ECV (r = − 0.715)  was observed. A relatively strong association between imaging markers of diffuse myocardial fibrosis  and diastolic function indicators was also observed.Macaca mulatta lasiotis, which was used in the present study. Like humans, the NHPs have an increased likelihood of developing obesity and T2DM with increasing age [In this study, rhesus monkeys with spontaneous T2DM were used. This non-human primate (NHP) model shares metabolic and pathological features with humans . Li Gongsing age . MonkeysThe methods used in our study to measure diastolic function were based on well-established echocardiographic techniques. The echocardiography findings presented in this study only demonstrated DD in monkeys with T2DM. These results concurred with the findings of the studies by Can  and HaihDD in T2DM with HFpEF is manifested as impaired relaxation and decreased diastolic chamber compliance . CollageAs has been demonstrated in previous studies in humans , 34, ECV1 on a time scale or in an intermediate exchange regimen is likely to play an important role in the modulation of T1ρ signals [Despite the performance of a few studies in ex vivo tissue, in vivo animals, and human patients , 13, 35, signals . In acco signals , an incr signals . It was r = 0.86) with the histological extracellular space component but only modestly correlated (r = 0.66) with the histological collagen volume fraction in patients with dilated cardiomyopathy. Future studies to systematically validate the mFI method with the use of histologically defined collagen volume are warranted, and they should include a sufficient sample size. Meanwhile, the relationship between collagen deposition and extracellular volume expansion is still in need of further investigation.Although a good correlation between mFI and ECV was found, there were still differences. The precise mechanisms that account for the different behaviors of ECV and mFI and that allow them to differentiate HCs from animals with mild DD remain unknown. One reason may be that increased ECV reflects the expansion of extracellular volume whereas increased mFI reflects the deposition of excessive collagen. In a recent study by Shiro and colleagues , ECV wasDue to the use of this rare, naturally occurring, chronic, NHP disease model of monkeys with T2DM as well as the longitudinal long-term study consideration, only one monkey with T2DM and DD was sacrificed for histopathology to show diffuse myocardial fibrosis. The ECV measurements in this study had not previously been validated in a monkey model. Given the close agreement of ECV among various species , 40, it In this initial study, monkeys with T2DM exhibited increased ECV, T1ρ, and mFI values, which may be indicative of the expansion of extracellular volume and the deposition of excessive collagen. The relationship between diastolic dysfunction and diffuse myocardial fibrosis was demonstrated by imaging markers. T1ρ mapping may have the potential to be used for the assessment of diffuse myocardial fibrosis.ESM 1(DOCX 32 kb)