Ischemic chronic cardiomyopathy (ICC) is still one of the most common cardiac diseases leading to the development of myocardial ischemia, infarction, or heart failure. The application of several imaging modalities can provide information regarding coronary anatomy, coronary artery disease, myocardial ischemia and tissue characterization. In particular, coronary computed tomography angiography (CCTA) can provide information regarding coronary plaque stenosis, its composition, and the possible evaluation of myocardial ischemia using fractional flow reserve CT or CT perfusion. Cardiac magnetic resonance (CMR) can be used to evaluate cardiac function as well as the presence of ischemia. In addition, CMR can be used to characterize the myocardial tissue of hibernated or infarcted myocardium. Echocardiography is the most widely used technique to achieve information regarding function and myocardial wall motion abnormalities during myocardial ischemia. Nuclear medicine can be used to evaluate perfusion in both qualitative and quantitative assessment. In this review we aim to provide an overview regarding the different noninvasive imaging techniques for the evaluation of ICC, providing information ranging from the anatomical assessment of coronary artery arteries to the assessment of ischemic myocardium and myocardial infarction. In particular this review is going to show the different noninvasive approaches based on the specific clinical history of patients with ICC. Ischemic chronic cardiomyopathy (ICC) still represents one of the most common cardiac diseases that can progress to acute myocardial ischemia or infarction, left ventricle (LV) dysfunction, or heart failure . Currently, a multimodality approach in ICC is appropriate for the correct assessment and management of these patients considering that each technique can have an important role for planning a correct therapeutic strategy ,3,4. Following the ESC guidelines, the role of coronary computed tomography angiography (CCTA) is rapidly increasing given the high negative predictive value of this technique in patients with suspected coronary artery disease (CAD) . AdditioHowever, given the low positive predictive value of CCTA , furtherCardiac Magnetic Resonance (CMR) represents another important noninvasive tool for the assessment of patients with ICC . A singlConsidering the low cost and wide distribution of technique, echocardiography remains the first technique to be used in the patient with ICC. There are multiple advantages of echocardiography compared to other imaging techniques, including its safety, relatively low-cost, and portability which allows for bedside evaluation. According to the European guidelines, rest echocardiography is recommended in all patients in the initial diagnostic management of patients with suspected coronary artery disease (Class I level B) . EchocarStress echocardiography is an established techniqufe, largely used for the assessment of known or suspected CAD with high diagnostic and prognostic value .Regarding nuclear imaging, single photon emission computed tomography (SPECT) is most commonly used for clinical myocardial perfusion imaging, whereas positron emission tomography imaging (PET), is the clinical reference standard for the quantification of myocardial perfusion.In this review, we provide an overview of multimodality imaging approach in patients with ICC, underlying the new development and the future applications of noninvasive imaging. Furthermore, we are going to emphasize the role of each technique based on clinical needs, in order to have a patient-based approach. The role of CCTA for management of suspicious CAD is rapidly increasing following the recommendation of European and American guidelines for the evaluation of patients with stable chest pain ,10.The mDue to the low positive predictive value of CCTA for CAD evaluation, CCTA does not represent the best technique for the evaluation of significant CAD ,11. DespIn terms of stenosis, CT can provide a qualitative or quantitative assessment of coronary stenosis assigning a final CAD-RADS score . The CADIn terms of follow up of patients with ICC, CAD-RADS classification may underestimate the progression of disease . SzilvesPlaque analysis represents another important advantage of CCTA over other noninvasive imaging techniques .The assoCCTA acquisition can provide information about plaque composition. In particular, CCTA can show the presence and extent of positive remodeling index, napkin ring signs, plaque burden, spotty calcification and volume of noncalcified plaque, which are associated with a worse prognosis ,19. Though analysis of plaque could represent an important role in terms of risk stratification, it is extremely important to consider that quantification of plaque components can be different based on the CT scanner  and tubeDespite the fact that the quantification of plaque it is not perfectly reliable, it is important to consider the potential application in the future in terms of follow up of patients with ICC. Different studies coming from the PARADIGM study evaluated changes of coronary artery disease ,22. In pThe role of CCTA can be extremely important in the evaluation of patients that underwent percutaneous coronary intervention  or coronFollow up of intrastent restenosis (ISR) can be extremely difficult but still feasible with CCTA . In partFurthermore, dual-energy technology, using virtual monochromatic images, allows the reduction of streak artifacts and provide iodine maps useful for a better evaluation of intrastent restenosis ,27,28. In those patients that underwent to CABG, CCTA can be extremely helpful for the evaluation of bypass patency ,29. It iCCTA, as mentioned above, can be extremely helpful in patients with ICC for the evaluation of coronary anatomy; however, its role is very limited for the evaluation of hemodynamically significant CAD and it could require further examinations such as stress echocardiography (SE), stress CMR, stress CT perfusion (CTP) or noninvasive imaging with nuclear medicine. Considering the low positive predictive value of CCTA in the presence of a moderate or severe stenosis, additional noninvasive testing could prove to be useful for the assessment of myocardial ischemia . Fractional flow reserve is defined as ratio between the blood pressure distal to a stenosis and the pressure before the stenosis during hyperemia . The appThere are several parameters that identify the FFRct as positive after the application of the FFRct algorithm. Nowadays, the addition of FFRct on top of CCTA allows for the reclassification of patients that underwent CCTA, thus increasing the positive predictive value for depiction of significant CAD ,32. This algorithm allows for the reduction of invasive coronary angiography in order to reclassify the patients based on the functional assessment of the plaque over the anatomical coronary stenosis . Beyond Similar to FFRct, stress CTP, regardless of the static or dynamic acquisition, can be extremely useful for the evaluation of myocardial ischemia over the plaque stenosis ,12,33. Contrarily to FFRct, the stress CTP requires the administration of a stress agent followed by another CT acquisition in single energy or dual energy . The interpretation of static stress CTP is more qualitative or semiquantitative, and it does not allow the evaluation of myocardial blood flow.  The lattFew studies evaluated the prognostic impact of stress CTP in clinical practice ,37,38. Meinel et al. demonstrated that segments deficient of stress CTP are strongly associated with a worse prognosis  while VaIn the setting of ICC, FFRct could have some limitation in clinical practice in patients with previous PCI and stent implantation , but FFRA correct approach using FFRct and stress CTP on top of CCTA can definitely provide identification of ischemic coronary plaques and steer the therapeutical approach. A representative case of FFRct and myocardial perfusion are shown in The goal of noninvasive functional tests for the diagnosis of obstructive CAD is to detect myocardial ischemia . CMR canA typical stress-CMR perfusion protocol is characterized by the administration of a vasodilator during contrast media injection with a series of perfusion sequences acquired at the basal, mid-cavity, and apical slices from the short-axis views.A perfusion defect is defined as a region of subendocardial hypointensity in a coronary distribution. This defect should be evaluated while the myocardium is perfused, rather than immediately upon contrast arrival within the left ventricular cavity  and should last for a few seconds. To differentiate perfusion defects caused by myocardial ischemia or myocardial fibrosis, this assessment must be accompanied by the evaluation of late gadolinium enhancement (LGE) images: the absence of LGE associated with a stress perfusion defect defines the presence of inducible ischemia. The number of segments with perfusion defects may be used to calculate the total ischemic load: according to ESC guidelines , the preFirst, Schwitter et al. reported in 2008 in the MR-IMPACT,  a multicMoreover, this technique has significant prognostic implications: as reported in the SPINS registry , a negatThe main disadvantages of stress-CMR perfusion are its low availability and the high level of expertise required. On the other hand, because of its clinical advantages, lack of ionizing radiation, and low cost, it is a radiological technique that will be used more frequently in the future to study myocardial ischemia, especially considering a more quantitative approach. Furthermore, it could represent a useful tool for the functional assessment on top of CCTA in presence of CAD that requires the evaluation of myocardial ischemia. A case of stress CMR is shown in Despite tissue characterization with CMR in patients with ICC could be obtained without administration of contrast agent using native T1 mapping ,51,52, iLGE sequences are acquired 10–15 min after the administration of gadolinium-based contrast agent ,53. In LThe standard sequences used for the evaluation of LGE are usually T1-weighted gradient echo acquisition reconstructed in magnitude or phase-sensitive ,55. Typical pattern of LGE in ischemic cardiomyopathy is represented by subendocardial LGE that can be extent in transmural scar . However, sometimes it is difficult to differentiate between scar and myocardial blood considering that both of them can appear hyperintense showing the same signal intensity . In ordeIn patients with hibernated myocardium, the absence of LGE or presence of subendocardial LGE with <50% of transmurality is considered viable . The “cuIn the setting of ICC, it is mandatory to evaluate the presence of LGE considering the important role in terms of LV recovery. Despite stress CMR can provide information regarding the myocardial ischemia, the presence of LGE, in the setting of ICC, allows the assessment of infarcted myocardium. This latter information provides the real advantage of CMR over the other techniques such as stress CTP or SE; in particular considering the transmurality of LGE. A representative case has shown in The most widely accepted echocardiographic parameter for LV systolic function assessment is left ventricle ejection fraction (LVEF), a measure derived from volumes assessment, defined as the ratio of stroke volume (end-diastolic volume–end-systolic volume) and end-diastolic volume. Clinical decision-making and patient management in several cardiovascular conditions primarily rely on LVEF ,64,65. IHowever, technical limitations and the dependence of image quality from the acoustic window, with consequent difficulty in distinguishing between the endocardium and the blood pool, make poor LVEF calculated by echocardiography poorly reproducible. In addition, as a volume-derived index, LVEF relies on geometric assumptions , is dependent on load and heart rate, is influenced by changes in LV geometry, and does not correspond to true LV contractility . Interestingly, volumes assessed with echocardiography in patients with ICC have an important diagnostic and prognostic value, independent from LVEF. Left ventricular dilatation at echocardiography is associated with a poor prognosis. In particular, a high end-systolic volume index is predictive of heart failure hospitalization inpatient with ICC . In clinical routine, LV volume measurements are usually obtained in transthoracic echocardiography using the biplane method of disk summation (modified Simpson’s rule) acquiring left ventricle (LV) volume from apical four- and two-chamber views, taking care to maximize LV area, avoiding apex foreshortening. On the contrary, the image acquisition in three-dimensional (3D) echocardiography should focus primarily on including the entire LV within the pyramidal data set as 3D echocardiography does not rely on geometrical assumption. For this reason, 3D echocardiography is recommended nowadays for volumes measurements when feasible, depending on imaging quality. . CompareIn order to partially overcome the limits of LVEF, new parameters have been proposed for the assessment of LV function in echocardiography. Between them, the most used are indices of myocardial deformation obtained with speckle-tracking echocardiography, such as strain and strain rate, proposed as adjunctive parameter to LVEF . Strain As the endocardial layer of the LV wall is more susceptible to ischemic injury in patients with cardiac ischemia, global longitudinal strain (GLS) is more affected than other parameters. It is more effective than LVEF in identifying patients with significant CAD . BieringNotably, the assessment of LV GLS with speckle-tracking echocardiography is related to long-term outcomes in patients with ICC. In a study of 1060 patients with ICC, GLS was independently related to all-cause mortality and heart failure .Thanks to its ubiquitous nature, portability, relatively low cost, and avoidance of ionizing radiation, SE is an attractive choice of test for a wide variety of patients  and has SE is able to detect myocardial ischemia by identification of wall motion abnormalities. Moreover, several prognostic parameters, including blood exercise duration, pressure response, ST-T changes, and LV dilatation, can be simultaneously assessed and enhance its diagnostic and prognostic role. . In termHowever, the test is dependent on the operator experience, and a poor acoustic window can hinder its diagnostic accuracy. Contrast echocardiography can improve image quality, reader confidence, and reproducibility for assessing both LV structure and function. Moreover, in patients with CAD and wall kinesis abnormalities, contrast agents can be used when thrombi are suspected but not clearly documented . In patiSpeckle-tracking echocardiography has also been proposed to reduce the subjectivity of image interpretation in SE. A recent study from Ilardi et al. demonstrated that strain evaluation improves visual wall motion assessment to detect inducible ischemia in the myocardial territories supplied by the left anterior descending artery in patients undergoing dobutamine stress echocardiography . FinallyThe major advantages of echocardiography are still represented by its low cost, wide availability and lack of ionizing radiation. Therefore, the role of echocardiography, in patients with ICC, is still fundamental in clinical practice allowing the evaluation of biventricular function and evaluation of ischemia. A representative case is shown in Myocardial perfusion imaging (MPI) with SPECT is one of the most performed noninvasive cardiac imaging tests. The biggest advantage of SPECT is that there is extensive clinical experience as well as an abundance of studies demonstrating the ability of SPECT in the diagnosis, risk stratification, treatment, and prognostic evaluation for patients with coronary artery disease ,80. ThisSeveral perfusion and nonperfusion markers have been proposed to improve detection of left main or three-vessel coronary disease ,93. Risk82Rb-chloride and13N-ammonia, with a small number of centers worldwide using 15O-water [15O]-water -water . SubsequO]-water ,111, incO]-water ,113. TheO]-water . NoninvaO]-water ,116,117.O]-water ,119. SimO]-water . Noninvasessment ,122. A msessment . The potsessment ,125 as wsessment . In ordeStress imaging with nuclear medicine is widely available in clinical practice, allowing the evaluation of myocardial ischemia. Although stress CTP, myocardial SPECT and myocardial PET require the use of ionizing radiation, it is important to consider that with CTP it is possible to evaluate CAD beyond myocardial ischemia. Compared to SE and stress CMR, using nuclear medicine it is possible to evaluate ischemic myocardium, however it is mandatory to consider the use of radiation. A representative case is shown in Nowadays a multimodality approach represents a fundamental tool for an appropriate management of patients with ICC. The multimodality approach in patients with ICC allows to develop different strategies based on the clinical history of patients and local expertise . The possibility to have a comprehensive and detailed evaluation of coronary plaque anatomy together with assessment of myocardial ischemia allows the possibility to have the best therapeutical approach. Indeed, the sequential strategy, due to a multimodality approach, can be extremely helpful for the correct identification, diagnostic pathway, providing a customized approach based on clinical needs. The future of integrated approach  in ICC will be revolutionized by the revolution of Artificial Intelligence applied to medical imaging . SeveralRadiomics is another interesting topic that will be further developed in the field of cardiovascular imaging ,138. UsiConsidering the aforementioned techniques, noninvasive imaging in patients with ICC is moving to a precision-based approach with a customized treatment, struggling to avoid unnecessary invasive procedures. Another interesting topic that should be underlined in patients with ICC, is the mandatory use of imaging for planning of the best surgical approach and selection of coronaries that should be revascularized. Therefore, it should not surprise that patients will undergo to several imaging techniques before CABG .An important issue that should be further explored in clinical practice is represented by the prognostic significance of plaque analysis versus ischemia for development acute cardiac events. Following the results of ISCHEMIA trial , it coulDespite the role of noninvasive imaging in patients with ICC can be complementary, it is not possible to ignore that in prognostic stratification some information obtained with noninvasive techniques can have different importance.In the future, in spite of multimodality imaging’s role in ICC, it will be extremely important to consider the balance between local expertise, clinical needs and economical sustainability. Considering the new ESC  and ACC In conclusion, a multimodality approach of patients with ICC is fundamental in the modern era for a better evaluation and follow up of CAD. In the future, the combination of data obtained with noninvasive multimodality imaging with AI, radiomics, clinical information according to sustainability and local expertise could play a key role for a better and faster classification and management of these patients.


Cancer therapy-related cardiac dysfunction may occur in pediatric cancer survivors. Identification of early markers of myocardial damage secondary to anthracycline exposure is crucial to develop strategies that may ameliorate this complication.The purpose of this study was to identify early myocardial changes induced by doxorubicin with and without cardioprotection using dexrazoxane detected by serial cardiac magnetic resonance imaging (CMR) in a pre-clinical mouse model.Serial CMR examinations were performed in 90 mice distributed in 3 groups: 45 received doxorubicin (DOX group), 30 mice received doxorubicin with dexrazoxane (DOX/DEX group) and 15 mice received saline injections (control group). We obtained the following CMR parameters in all mice: T2, extracellular volume quantification (ECV), myocardial deformation, and functional quantification.Myocardial edema assessed by T2 time was the earliest parameter demonstrating evidence of myocardial injury, most notable in the DOX group at week 4 and 8 compared with DOX/DEX group. Similarly, global longitudinal strain was abnormal in both the DOX and DOX/DEX groups. However, this change persisted only in the DOX group. The ECV was significantly elevated in the DOX group at the final CMR, while only minimally elevated in the DOX/DEX group. The right and left ejection fraction was decreased, along with the mass to volume ratio in the DOX group. The T2 time, ECV, and deformation correlated with ejection fraction and left ventricular volume.T2 time and deformation by CMR identifies early myocardial injury from anthracyclines. Dexrazoxne did not prevent the initial edema, but the inflammatory changes were not sustained. CMR may be useful for early detection of cardiac dysfunction. Serial CMR demonstrates dexrazoxane minimizes cardiac dysfunction and aids recovery in a mouse model.The online version contains supplementary material available at 10.1186/s40959-021-00109-8. Cancer therapy-related cardiac dysfunction is one of the leading causes of morbidity and mortality in pediatric cancer survivors. The identification of early changes in the myocardium secondary to cancer therapy may assist with the development of different strategies to mitigate this effect. Our study utilizing a pre-clinical mouse model demonstrated that early myocardial changes occur with doxorubicin even when it is administrated in conjunction with dexrazoxane. However, chronic inflammation and subsequent ventricular dysfunction due to doxorubicin may be mitigate by cardioprotection with dexrazoxane. In addition, our study included GLS in a pre-clinical mouse model as one of the parameters to evaluate myocardial damage after anthracycline exposure. We observed that GLS was impaired in mice that received doxorubicin as it has been described in cancer patients. Our results support previous studies that advocate for a widespread use of cardiac MRI in pediatric cancer patients in larger clinical to monitor for the deleterious cardiotoxic effects exert by chemotherapy.The rates of survival of pediatric cancers have risen considerably over the past four decades. One reason for improvement is the use of combination chemotherapy. Several anthracyclines, a class of chemotherapy drugs, have become the mainstay of treatment for different pediatric cancers . HoweverTrans-thoracic echocardiography (TTE) remains the primary imaging modality to monitor for signs of CTRCD due to its wide availability, lack or radiation exposure, capacity to assess hemodynamics and lower cost. However, TTE is unable to detect myocardial edema and fibrosis resulting from cardiomyocyte injury, and typically evaluates for CTRCD by measures of global systolic function such as left ventricle shortening fraction (LVSF) or left ventricle ejection fraction (LVEF). In addition, evaluation of cardiotoxicity with TTE has a predilection to overestimate the LVEF, and may fail to identify patients with early left ventricle dysfunction , 10. TheCardiac magnetic resonance imaging has superior quantification of left ventricle (LV) size and LVEF compared to traditional 2-dimensional TTE, and indicates the degree of myocardial edema and extracellular volume (ECV) fraction secondary to myocardial damage. Therefore, CMR could be considered the imaging reference standard to evaluate for heart failure and detect early stages of this disease –14. A sen = 45), doxorubicin + dexrazoxane  or placebo with saline injection . The DOX group received doxorubicin 3 mg/kg once per week by intraperitoneal injection for a total of 6 weeks. The DOX/DEX group received doxorubicin 3 mg/kg plus dexrazoxane 30 mg/kg intraperitoneal injection once per week for a total of 6 weeks. These doses were chosen to simulate the development of anthracycline-induced cardiotoxicity. The control group received intraperitoneal saline (same volume as the DOX group) once per week for 6 weeks.This study was approved by Baylor College of Medicine Institutional Animal Care Use Committee. This was a longitudinal study of 90 wild-type C57BL/6 mice  aged 6–8 weeks randomized to doxorubicin  size, LVEF, RVEF, myocardial edema evaluated by average T2-relaxation time, myocardial fibrosis assessed by ECV and myocardial strain. The CMR variables were assessed at 4 weeks (during chemotherapy administration), 8 weeks (2 weeks after conclusion of chemotherapy) and 12 weeks (6 weeks after conclusion of chemotherapy). Images were obtained 48–72 h after dexrazoxane and doxorubicin administration on week 4. The primary outcome of the study was the presence of ventricular dysfunction, which was defined as decrease in LVEF or RVEF below 50%. The CMR parameters were analyzed by individuals blinded to the treatment groups.o; repetition time, 8.85 ms; echo time, 2.36 ms; matrix, spatial resolution, 0.13 × 0.15 mm. The conventional CMR parameters of RV and LV end-diastolic volume, the LV mass, the RV and LV EF were analyzed on the fast gradient-echo sequence using commercially available software, CVI 42 . To assess the myocardial edema, T2-relaxation time was quantified. A respiratory and electrocardiogram-gated, multiecho, ventricular short-axis, spin-echo sequence was performed with 5 spin-echo times . The sequence was performed prior to contrast administration with the following parameters: single slice at mid-ventricular level, slice thickness of 1 mm, matrix of 128 × 128, spatial resolution of 0.23 × 0.23 mm, and 2 averages. Triggering was done at usually every second to third cardiac cycle with a repetition time of 200 to 400 ms. To quantify T2-average, the endocardial and epicardial border on the mid-ventricular slice, as it had the best image quality, was traced for all echo times and analyzed using commercially available software, CVI 42 . A region of interest was traced in the LV free wall and interventricular septum and averaged together. Myocardial fibrosis was assessed by measuring the extracellular volume fraction (ECV). The ECV was calculated by pre-contrast and post-contrast T1 measurements. For measurement of the T1 time, a gadolinium-based contrast agent (0.2 mmol/kg) was diluted in saline at a 1:10 ratio and given via intraperitoneal injection. Similarly to T2 quantification, the T1 was measured at the LV mid-ventricular level in a short-axis slice, both pre-contrast and at several intervals post-contrast using a Look-Locker technique. The Look-Locker sequence was electrocardiogram-gated with a non-slice selective inversion pulse with the following parameters: gradient-echo readout, flip angle 10o, repetition time 2.2 ms, echo time 1.6 ms, in-plane resolution of 0.13 × 0.15 mm, slice thickness of 1 mm, repetition time per segment of 22 ms, and number of averages 6 (pre-contrast) or 4 (post-contrast). The post-contrast sequence was performed every 6–8 min following intraperitoneal contrast injection. A region of interest was drawn in the LV free wall and interventricular septum at each time interval, plotted over time and then averaged together for myocardial T1 time. A similar process was performed for a region of interest in the blood pool for ECV calculation. The ECV was calculated using known hematocrit for the mice strain. The global circumferential and longitudinal strain  were acquired at a mid-ventricular short-axis slice for GCS and a single 4-chamber slice for GLS by using a Complementary Spatial Modulation of Magnetization (CSPAMM) technique. The following parameters were used for each sequence: flip angle 20o, repetition time7 ms, echo time 3 ms, in-plane resolution of 0.14 × 0.14 mm, slice thickness of 1 mm. The gridlines were analyzed for global peak strain values using commercially available software, Myocardial Solutions .Serial CMR examinations were performed on a Bruker 9.4-T CMR imaging machine as previously described , 17 For p-values less than 0.05.The R statistical environment was used to perform a one-way ANOVA followed by a post-hoc analysis using the Tukey HSD test on the CMR parameters in relationship to the treatments. Pearson and Spearman correlations between the CMR parameters at the measured time points were calculated using the R statistical environment. Correlations were considered statistically significant for A logistic generalized linear model was developed in the R statistical environment to predict ventricular dysfunction. Ventricular dysfunction in our model occurs when the LVEF or RVEF was less than or equal to 50%. The parameters measured at 4 weeks were used to predict dysfunction at either 8 or 12 weeks and the parameters measured at 8 weeks were used to predict dysfunction at only 12 weeks. For a one-parameter model a Chi-squared test was used to determine if the model performed better than a constant intercept only model. When we added a second parameter to the model a Chi-squared test was again used, but we compared the two-parameter model to the following one-parameter models: LVEF, RVEF, GLS or T2 time. Receiver operator curves were generated using the ROCR package in the R statistical environment .All treatments were administrated without complications. We did not observe any death due to drug toxicity. Mice were euthanized at the end of the study as originally intended.Cancer therapy-related cardiac dysfunction is characterized by increases in ventricular size and decrease in ventricular function, which were measured by LV volume, LV mass to volume ratio and both right or left EF in our experimental design. All of the mice in the DOX group demonstrated a decrease in LVEF and RVEF to levels below 50% at the week 12 time point. One mouse died after the week 4 time interval. The DOX/DEX group demonstrated 7 of the mice having LVEF below 50% while 12 of the mice had RVEF below 50%. None of the control mice demonstrated LVEF below 50%, and 3 mice demonstrated a RVEF below 50%. Although LV volume significantly increased in all experimental groups, the effect was more noticeable in the DOX and DOX/DEX groups compared to the control group at all evaluated time points , the p-value from a Chi-squared test comparing the one-parameter model to an intercept only model was statistically significant , and the area under the curve (AUC) from a receiver operator curve was greater than 0.70. The AUC measures how well a model classifies different states. An AUC of 0.5 indicates that the models has a 50% chance of predicting two different states while and AUC of 1.0 indicates that the model is perfectly accurate. The parameters LVEF, RVEF, GLS and T2-average were good predictors of dysfunction at 12 weeks when the parameters were measured at both 4 and 8 weeks , edema T2-average) and deformation (GLS) tended to be negatively correlated with ejection fraction, LV mass and LV volume , the p-values for the Chi-squared test comparing the two-parameter to the one-parameter models RVEF, LVEF, GLS and T2-average were all statistically significant , and the AUC from the receiver operator curve was greater than 0.70. Using this criteria, we found that the model combining the CMR parameters T1-post plus T2- average was a good predictor of dysfunction at 12 weeks when the parameters were measured at 4 weeks  by doxorubicin, but it did limit the degree of edema formation and perhaps more importantly, it prevented the chronic inflammation characterized by persistent fibrosis (ECV) and worsening contractile function (GLS).We observed the early development of myocardial edema in mice exposed to anthracycline. This is similar to the results obtained by Farhad et al., and Galan-Arriola et al., that also observed the appearance of myocardial edema in different animal models using CMR imaging after doxorubicin treatment , 16. HowSimilar to the previous study by Farhad et al., we observed a continuous expansion of the ECV in the anthracycline group. However, our study distinctly demonstrated that the cardioprotection group, as well as the control group, did not have an expansion in the ECV. This result indicates the cardioprotective effect of dexrazoxane in the myocardium attenuates the development of myocardial fibrosis. The ECV expansion demonstrated a negative correlation with LVEF and to predict an increase in cardiovascular morbidity and mortality in large adult studies , 22. PedAnother unique feature of our model compared to previous pre-clinical studies was the inclusion of myocardial deformation. We observed worsening of the GLS at the earliest CMR time interval  in the experimental group that received doxorubicin. Nevertheless, cardioprotection with dexrazoxane appeared to somewhat attenuate that effect as there was no difference at the 4 week time interval between the cardioprotection group and the control group. However, this finding did not hold at the later time interval of 8 weeks. Deformation imaging by TTE has become more prevalent in its use for detecting cardiac dysfunction in patients receiving cancer treatment , 24. SimCardiac magnetic resonance imaging is the reference standard to measure cardiac volume and mass, and thus is optimally suited to characterize the cardiac remodeling process. Our study demonstrated an expansion of the LV volume with a relative decrease in the LV mass to volume ratio. This finding was seen only in the group treated with doxorubicin compared to the cardioprotection and control groups. This finding continues to support the observation that initial myocardial edema may be present even with the use of dexrazoxane, but expansion of the LV volume and “thinning” of the LV wall do not occur. The expansion of the LV volume is more related with the development of dilated cardiomyopathy, as it has previously been reported in pediatric cancer survivors , 28. We Cardiac magnetic resonance has become the imaging reference standard to evaluate for ventricular volume, ventricular mass and EF in different cardiac diseases, and provides better characterization of the myocardium . Our stuThe main limitation of our study is the use of a mouse model. There is significant variability using animal models to study the effect of anthracycline on cardiac remodeling, and thus our results may be relevant only to this mouse model. Nevertheless, we consider that our findings increase our knowledge about CTRCD and our results should be evaluated in patients exposed to anthracyclines. Another limitation is the lack of correlative histology evaluation of chronic inflammation. However, ECV have been closely correlated with myocardial fibrosis in previous studies , 15.T2 time and deformation by CMR appears to identify early myocardial injury from anthracyclines. Dexrazoxne did not seem to prevent the initial edema as gauged by T2 time, but the inflammatory changes were not sustained. CMR may be useful for early detection of cardiac dysfunction. Serial CMR demonstrates dexrazoxane minimizes cardiac dysfunction and aids recovery in a mouse model.Additional file 1: Supplemental Table 1. Correlation Between Parameters as Time Progresses in Control Samples.Additional file 2: Supplemental Table 2. Correlation Between Parameters as Time Progresses in Doxorubicin Samples.Additional file 3: Supplemental Table 3. Correlation Between Parameters as Time Progresses in Doxorubicin plus Dexrazoxane Samples.Additional file 4: Supplemental Table 4. Two Parameter Model Performance.Additional file 5.Additional file 6.Additional file 7.Additional file 8.


Background: Distinguishing the etiology of left ventricular hypertrophy (LVH) is clinically relevant due to patient outcomes and management. Easily obtained, echocardiography-based myocardial deformation patterns may improve standard non-invasive phenotyping, however, the relationship between deformation phenotypes and etiology-related, microstructural cardiac remodeling has not been reported. Synchrotron radiation-based X-ray phase-contrast imaging (X-PCI) can provide high resolution, three-dimensional (3D) information on myocardial microstructure. The aim of this pilot study is to apply a multiscale, multimodality protocol in LVH patients undergoing septal myectomy to visualize in vivo and ex vivo myocardial tissue and relate non-invasive LVH imaging phenotypes to the underlying synchrotron-assessed microstructure.Methods and findings: Three patients (P1-3) undergoing septal myectomy were comprehensively studied. Medical history was collected, and patients were imaged with echocardiography/cardiac magnetic resonance prior to the procedure. Myocardial tissue samples obtained during the myectomy were imaged with X-PCI generating high spatial resolution images (0.65 μm) to assess myocyte organization, 3D connective tissue distribution and vasculature remodeling. Etiology-centered non-invasive imaging phenotypes, based on findings of hypertrophy and late gadolinium enhancement (LGE) distribution, and enriched by speckle-tracking and tissue Doppler echocardiography deformation patterns, identified a clear phenotype of hypertensive heart disease (HTN) in P1, and hypertrophic cardiomyopathy (HCM) in P2/P3. X-PCI showed extensive interstitial fibrosis with normal 3D myocyte and collagen organization in P1. In comparison, in P2/P3, X-PCI showed 3D myocyte and collagen disarray, as well as arterial wall hypertrophy with increased perivascular collagen, compatible with sarcomere-mutation HCM in both patients. The results of this pilot study suggest the association of non-invasive deformation phenotypes with etiology-related myocyte and connective tissue matrix disorganization. A larger patient cohort could enable statistical analysis of group characteristics and the assessment of deformation pattern reproducibility.Conclusion: High-resolution, 3D X-PCI provides novel ways to visualize myocardial remodeling in LVH, and illustrates the correspondence of macrostructural and functional non-invasive phenotypes with invasive microstructural phenotypes, suggesting the potential clinical utility of non-invasive myocardial deformation patterns in phenotyping LVH in everyday clinical practice. The contemporary approach to diagnosing LVH is based on non-invasive multimodality imaging [echocardiography and magnetic resonance (CMR)] – where LV chamber size/shape remodeling, distribution of hypertrophy/fibrosis, and functional alterations form the basis for diagnosis , 2. Carductively –7 – provin vivo and ex vivo myocardial tissue with non-invasive and X-PCI imaging, respectively, and relate non-invasive LVH imaging phenotypes to the underlying synchrotron-assessed microstructure . The most prevalent gene mutations involved in cardiomyopathies were scanned , laminopathies, Danon disease, dilatative CM, arrhythmogenic CM, non-compaction CM, Marfan syndrome, long QT syndrome, Holt-Oram, Ehlers-Danlos, and Brrugada syndrome). A generational family pedigree was assessed to explore the genetic origin of disease.The population under study were three patients (P1-3) with obstructive LVH referred for septal myectomy from the familiar cardiomyopathy outpatient clinic. At the moment of inclusion, a clinical interview was performed. Medical history was reviewed and data on demographic characteristics, cardiovascular risk factors, comorbidities, pharmacological treatment was collected. The 5-year HCM risk score was evaluated . Upper aGE, Vingmed Ultrasound, Horten, Norway) equipped with a 4Vc transthoracic transducer. In addition to full two-dimensional and Doppler echocardiography, additional parasternal short-axis, and 4-chamber, 2-chamber, and 3-chamber apical acquisitions with appropriate frame rates were obtained for speckle-tracking and Tissue Doppler analysis, respectively.All participants underwent a comprehensive transthoracic echocardiographic examination, prior to the surgical myectomy, performed on a commercially available E95 system . The endocardial border was manually marked at end-systole of the LV. A region of interest with six segments was automatically generated. If needed, manual adjustments were performed to achieve optimal tracking. Longitudinal strain curves were generated and end-systolic strain, defined by the aortic valve closure time, measured. The LV global longitudinal strain was calculated by averaging values of the 18 segments. The focus of analysis was the basal and mid septal region, as this is where myocardial tissue is removed during septal myectomy. Regional deformation was therefore explored by placing the region of interest (ROI) in different parts of the interventricular septum. TDI-derived deformation was assessed using color-coded maps of myocardial deformation and by determining ROIs to generate regional TDI-derived longitudinal strain curves of myocardial areas within the adjacent ventricular segment.Resting LVOT peak velocity was measured by using continuous-wave Doppler echocardiography, and the LVOT pressure gradient peak estimated by using a simplified Bernoulli equation. The maximal LVOT gradient was defined as the highest recorded gradient, either in rest of during Valsalva maneuver. Pulsed-wave Doppler was performed in the apical 4-chamber view by placing the sample volume at the level of the leaflet tips to obtain mitral inflow velocities. Peak velocity of early (E) and late (A) diastolic filling, E velocity deceleration time and A wave duration were measured, and the E/A ratio calculated. Isovolumic relaxation time (IVRT) was measured as the time difference between aortic valve closure and mitral valve opening as assessed in the five-chamber view using continuous-wave Doppler of the LV outflow tract. Tissue Doppler was used to measure early and late diastolic mitral annular velocity at the septal  and lateral  annular sites. Myocardial deformation of the left ventricle (LV) was assessed with speckle tracking echocardiography (STE) on 2D grayscale images obtained from the three apical cardiac views and with tissue Doppler deformation imaging (TDI) in the 4-chamber view – both using GE Echopac software (All cardiac magnetic resonance (CMR) exams were performed in a 3.0 Tesla scanner , equipped with a 32-channel chest coil. All images were ECG-triggered and obtained in apnea. Standard short axis SSFP cines were obtained  in order to calculate left and right ventricular volumes and function. Additionally, 4-, 3-, and 2-chamber SSFP cines were acquired. A standard phase contrast in-plane flow sequence in a 3-chamber view orientation  was acquired in order to assess for the presence of flow obstruction. An additional through-plane phase contrast image was obtained at the point of maximal turbulence; VENC was appropriately adjusted in each case to avoid aliasing. A perfusion sequence in three standard short axis orientations  was obtained after administration of a single bolus of gadolinium-based contrast (0.15 mmol/kg). Seven min after contrast administration a standard Look-Locker sequence was acquired and the optimal inversion time selected for each patient. Immediately after, late gadolinium enhancement imaging (inversion recovery gradient echo and PSIR sequences) was acquired using the same imaging planes, slice thickness and spacing as the cine images; inversion time was adjusted during the acquisition, if necessary.DiaPath SafeCapsule 31.7 ml). Tissue samples were measured and photographed for reference.Septal tissue samples were obtained as a part of the planned surgical procedure performed at the center. Patients underwent myectomy as previously described . No addiVilligen, Switzerland) according to the participating institution's ethical recommendations and the governing international legal requirements. Due to limited available beamtime, only the largest removed pieces of tissue were selected for scanning. The tissue was imaged using X-PCI. A multiscale protocol combining a low-resolution (LR) and a high-resolution (HR) setup  was used0  with a sample-detector distance of 333 cm. X-rays were converted to visible light through a LuAG:Ce 300 μm scintillator and detected by a sCMOS camera (PCO Edge 4.2). LR scans correspond well to traditional histology , with a sample-detector distance of 20 cm, a LuAG:Ce 20 μm scintillator and a PCO. Edge 5.5 CMOS detector. Additionally, 50 pre-flat, 50 post-flat and 50 dark images were acquired for flat-field and dark-field corrections of each acquisition. The acquired projections were reconstructed using the Gridrec algorithm. In the case of HR, the single distance phase retrieval method developed by Paganin was applied  (Ilastik (collagen segmentation)   and the ntation)  with thecollagen .Information on family history of HCM, demographic data and medical history is shown in row, yellow arrow). Global longitudinal strain was reduced, whereas regional STE deformation analysis revealed impaired deformation at both the basal, basal/mid and mid septum , associated with post-systolic shortening (PSS) (yellow arrows). Upon further exploration with TDI, areas with reduced deformation and PSS were identified in the basal septum.P1 had normal LV cavity dimensions, showing concentric LVH combined with pronounced basal anteroseptal hypertrophy (19 mm) , while Lrow, yellow arrows). While global longitudinal strain was only slightly reduced, septal regional STE deformation analysis showed a heterogeneous deformation pattern: reduced, but normally profiled deformation in the basal segment (yellow curve), virtually completely absent deformation on the transition from basal to mid region (pink curve), and normalizing deformation toward the apex (blue and green curves). Exploration with color-coded TDI and TDI deformation curves confirmed these findings visualizing an isolated area with very abnormal deformation in the transition from basal to mid septum .P2 had normal LV dimensions and an asymmetric LVH localized in the inferoseptal region (17 mm) , with foyellow, pink and blue curves), returning to normal values in the apex (green curve). Color-coded TDI and TDI deformation curves, based on smaller, more focused regions of interest, revealed an underlying heterogeneous deformation pattern. Deformation in the basal region was, in fact, normal (yellow curve), whereas the transition from basal to mid septum showed completely abnormal deformation (blue curve), slowly recovering toward the apical region (green curve).P3 had a slightly dilated LV, with an extreme, asymmetric LVH, localized throughout the whole septum (37 mm), and paired with severe enhancement in the septum and inferior interventricular junction . While eorange frame, yellow frame). The segmented 3D collagen distribution was visualized . LR revealed regions of normal myocardial organization (orange frame) alternated with patches of myocyte disarray  showed increased fibrosis (13.4%), highly disorganized, except in the smaller regions of normal organization  fibrotic patch on the endocardial side  analysis. Multiscale analysis with CMR may provide better soft tissue contrast, however, at much lower resolutions and/or prolonged scan time. Furthermore, CMR-based techniques rely on indirect measures of myocardial structure, through the use of contrast agents or diffusion tensor imaging, whereas with X-PCI we can directly measure myocardial structure based on changes in X-ray intensity and phase. On an important note, X-PCI is currently a research methodology, and as such it is linked to synchrotron facilities with limited accessibility. Integration of X-PCI technology in traditional hospital CT machines is for now still not feasible (ex vivo use – particularly for imaging tissue biopsies. Application of these tools has already been suggested – for clinically relevant topics such as the assessment of ex vivo endomyocardial tissue in heart transplantation patients to assess graft rejection with more reproducibility (in vivo to clarify ambiguous findings in traditional mammography (In a more clinical perspective, continuing evidence point out the inconsistencies of the single sarcomere gene hypothesis in HCM, suggesting the need to incorporate the influences of numerous disease modifiers, each exerting a small effect on phenotype expression –52. Herefeasible , but thefeasible  and gratfeasible  may leadcibility , or assemography .in vivo and ex vivo analysis of a small sample, with the goal of applying existing X-PCI technology to the field of cardiac imaging to provide a novel visualization of microstructural organization in LVH, and to generate a hypothesis of structure/function relations by linking these invasive findings to non-invasive imaging phenotypes. Nonetheless, no causation can be claimed based on these initial results. The results motivate larger patient cohorts to enable statistical analysis/group comparison, as well as the assessment of reproducibility of deformation patterns (Our pilot study consisted of a detailed, multi-modality patterns .All imaged tissue samples were derived from surgical myectomy; therefore, the sample size was limited and potentially not representative of the heart as a whole. However, septal tissue has consistently demonstrated structural abnormalities in prior studies , 25, 52.High-resolution, 3D X-PCI provides novel ways to visualize myocardial remodeling in excised myectomy tissue, and illustrates the correspondence of macrostructural and functional non-invasive phenotypes with invasive microstructural phenotypes, suggesting the potential clinical utility of non-invasive myocardial deformation patterns in phenotyping left ventricular hypertrophy. A larger patient cohort could enable statistical analysis of established differences and the assessment of the reproducibility of deformation patterns.http://doi.psi.ch/detail/10.16907%2Fb97cdb87-83be-4176-87f4-2e89679ff333.The data presented in the study are deposited in the PSI Public Data Repository, accession number The studies involving human participants were reviewed and approved by Ethics Committee of the Hospital Clinic of Barcelona. The patients/participants provided their written informed consent to participate in this study.FL: conception, design, analysis and interpretation of data, and drafting of the manuscript. PG-C: analysis and interpretation of data, drafting of the manuscript, revising for important intellectual content, and final approval of the manuscript submitted. AG-A, HD, and AB: conception and design, revising for important intellectual content, and final approval of the manuscript submitted. LS, SP, AD, EQ, and DP: revising for important intellectual content and final approval of the manuscript submitted. MS and BB: conception and design, interpretation of data, revising for important intellectual content, and final approval of the manuscript submitted. All authors contributed to the article and approved the submitted version.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.


Higher TMAO values at 24 h were correlated to smaller infarct sizes . Larger declines between admission and 4 months suggestively correlated with smaller infarct size, and larger TMAO increases between 24 h and 4 months were associated with larger infarct size . Upon eGFR stratification using 90 mL/min/1.73 m2 as a cut-off, significant associations between TMAO and infarct size were only noted in subjects with impaired renal function. In conclusion, TMAO levels in post-PCI STEMI patients are prone to fluctuations, and these fluctuations could be prognostic for infarct size, particularly in patients with impaired renal function.The gut metabolite trimethylamine N-oxide (TMAO) at admission has a prognostic value in ST-elevation myocardial infarction (STEMI) patients. However, its sequential changes and relationship with long-term infarct-related outcomes after primary percutaneous coronary intervention (PCI) remain elusive. We delineated the temporal course of TMAO and its relationship with infarct size and left ventricular ejection fraction (LVEF) post-PCI, adjusting for the estimated glomerular filtration rate (eGFR). We measured TMAO levels at admission, 24 h and 4 months post-PCI in 379 STEMI patients. Infarct size and LVEF were determined by cardiac magnetic resonance 4 months after PCI. TMAO levels decreased from admission (4.13 ± 4.37 μM) to 24 h (3.41 ± 5.84 μM,  Preventative and therapeutic efforts have contributed to the decline of coronary heart disease (CHD)-related mortality in the past decades. Nevertheless, CHD remains the main global cause of death with rates exceeding 9 million deaths per year, thereby underscoring the importance of furthering our current understanding of this disease ,2,3.Atherosclerosis hallmarks CHD, and efforts are currently being directed at better understanding the manner through which this inflammatory process contributes to the development of CHD. Trimethylamine N-oxide (TMAO), a gut microbial product derived from L-carnitine and choline-rich foods, has gained substantial attention due to its atherogenic potential and its impact on CHD prognosis and all-cause mortality ,6,7,8,9.While these aforementioned efforts have certainly delineated the value of pre-PCI TMAO levels in STEMI patients, the relevance of circulating TMAO in the post-PCI context remains elusive. Furthermore, data on the relationship between TMAO and infarct-related outcomes in STEMI patients, which could potentially explain the current established prognostic value of TMAO, is scant. For these reasons, the aim of the current study is to (i) delineate the temporal course of TMAO levels in STEMI patients who underwent primary PCI, and (ii) to outline the link between TMAO levels and infarct-related outcomes 4 months after the occurrence of STEMI.2), and standard contraindications for magnetic resonance imaging (MRI) [Our study included all patients enrolled in the ‘Glycometabolic Intervention as Adjunct to Primary Coronary Intervention in ST Elevation Myocardial Infarction‘(GIPS-III) trial. This clinical trial aimed to delineate whether metformin treatment preserved left-ventricular ejection fraction (LVEF) in STEMI patients without diabetes . In shorng (MRI) . The GIPng (MRI) . Furtherng (MRI) . Patientng (MRI) .Out of the 1473 STEMI patients admitted to the UMCG between January 2011 and May 2013, 379 subjects befitted the inclusion criteria and were included in our analysis.Standard physical examination parameters and routine laboratory values were measured at admission as per protocol. Patients returned to the outpatient clinic for follow-up at 2 weeks, 7 weeks, 4 months, and 1 year after discharge. Blood was sampled at these timepoints according to protocol to allow for the routine measurement of common laboratory parameters  ,13,14. A1H-nuclear magnetic resonance (NMR) spectroscopy employing a Vantera® Clinical Analyzer  as previously reported [v/v). The Carr-Purcell-Meiboom-Gill (CPMG) acquisition technique was used to obtain NMR spectra, after which TMAO was quantified from TMAO peaks using a non-negative least squares fitting algorithm and subsequently converted to concentration units (μM) through an empirically determined conversion factor. The TMAO assay has intra- and inter-assay coefficients of variation (CV%) that range from 4.3–10.3% and 9.8–14.5%, respectively [Plasma TMAO was quantified using NMR by reported . To sepaectively .t test, Mann–Whitney U test, Chi-square or Fisher’s exact test.Baseline characteristics were expressed as means ± standard deviation when normally distributed, as medians with interquartile ranges when non-normally distributed, or as frequencies and percentages for categorical variables. Differences between groups were determined by Student 2 as two different cut-off values), seeing that renal impairment has been reported to confound the associations between TMAO and cardiovascular disease [The temporal course of TMAO at admission and in the post-PCI context was studied using a mixed model with random intercepts followed by a pairwise comparison with a Bonferroni correction to delineate differences between specific timepoints. Additionally, we calculated Spearman rank correlation coefficients between TMAO values and infarct-related outcomes at and across the different time points. This analysis was reiterated twice after stratification of subjects based on their admission eGFR values . Baseline characteristics stratified according to eGFR values at admission with 90 mL/min/1.73 m2 as cut-offs are presented in 2 can be found in Baseline characteristics are presented in p = 0.001). Post hoc pairwise comparison with an applied Bonferroni correction outlined that the reductions in TMAO levels between admission and 24 h and subsequent increase between 24 h and 4 months were statistically significant .p = 0.024 and rho = −0.19, p = 0.008, respectively). Furthermore, larger TMAO increases between 24 h and 4 months were correlated with larger infarct sizes  , and the TMAO increase between 24 h and 4 months became significantly associated with infarct size . Additionally, these patients exhibited a positive suggestive correlation between larger increases in TMAO values between admission and 4 months and LVEF . Comparing the correlations of the two different groups using a regression model with an interaction term (eGFR × TMAO) showed that the correlations for infarct size suggestively, and significantly, differed for the decline in TMAO levels between admission and 4 months, and the TMAO increase between 24 h and 4 months, respectively , and that the correlations for LVEF suggestively differed for delta TMAO levels between 24 h and 4 months (p = 0.013). Lastly, no significant correlations were observed between TMAO values and infarct-related outcomes when subjects were stratified using 60 mL/min/1.73 m2 as a cut-off value for eGFR.Some of these suggestive findings persisted and became significant after eGFR stratification with 90 mL/min/1.73 m/1.73 m2 . To illu2 as a cut-off value accentuated the association between TMAO and infarct size in subjects with eGFR < 90 mL/min/1.73 m2.We investigated the sequential changes of TMAO and its relationship to infarct-related outcomes before and after adjusting for kidney function in STEMI patients. The major findings of the present study were as follows: (i) TMAO levels significantly decreased within the first 24 h after PCI and returned to baseline values after 4 months, (ii) TMAO exhibited suggestive associations with infarct size but not with LVEF, and (iii) eGFR stratification with 90 mL/min/1.73 mPlasma TMAO levels are prone to influence by an array of factors, including but not limited to gut microbiome composition, dietary choline and L-carnitine intake, and genetic heterogeneity of the hepatic flavin monooxygenase 3 enzyme responsible for the generation of TMAO from trimethylamine ,20. IndeOur analysis is the first in (i) delineating changes in TMAO levels across three different timepoints and (ii) reporting such temporal patterns within the first 4 months in STEMI patients who underwent PCI. The drop in TMAO values within the first 24 h of admission in the present cohort indicates that TMAO is prone to acute changes in the post-PCI setting. We could not, however, pinpoint the precise reason behind such variation as subjects were not necessarily fasted, nor were they expected to follow a prespecified dietary regimen upon admission. Analyzing such dietary parameters is of central importance as TMAO has been shown to exhibit volatile changes in response to acute changes in dietary patterns. In a pilot study including healthy participants randomized to a 24 h water-only fast or a 24 h ad libitum fed diet, Washburn et al. reported a significant decrease of TMAO levels at the end of a fasted day, which subsequently returned to admission values within 24 h from the start of the refeeding phase .p = 0.048). Furthermore, the difference in the temporal period used to measure changes in TMAO levels between their investigation (10 months) and ours (4 months) could also be a reason behind this discrepancy.The only other report describing the sequential change of TMAO after PCI in STEMI patients is that of Matsuzawa et al. In their cohort, TMAO significantly increased between admission (median: 5.63 μM) and 10 months (6.76 μM) . While oIn addition to the state of post-PCI perfusion, we analyzed the relationship between TMAO and infarct size, as well as LVEF, as both are important predictors of STEMI prognosis . StudiesIn our study, greater TMAO declines between admission and 4 months reflected smaller infarcts, and greater TMAO elevations between 24 h and 4 months were suggestively correlated to larger infarcts. It is established that the extent of inflammation—a process to which TMAO is linked—in the reperfusion phase is pivotal in determining the size of the infarct ,31,32. S2). In the impaired kidney function group (eGFR < 90 mL/min/1.73 m2), however, such stratification accentuated some of the suggestive associations into becoming significant, where greater TMAO declines between admission and 4 months became significantly associated with smaller infarcts and greater TMAO elevations between 24 h and 4 months became significantly correlated to larger infarcts. These findings are of relevance in as much as the relationship between TMAO and kidney function is a current topic of discussion. Not only is plasma TMAO mostly cleared by the kidney, but a “uremic environment”—characteristic of CKD patients—may also elevate plasma TMAO levels through promoting dysbiosis of the gut microbiome [2) was shown to be associated with lower LVEF and greater infarct sizes [2 eGFR group does not necessarily refute the confounding possibility, seeing that such group comprised of only 14 subjects. In terms of LVEF and its association to TMAO (or changes thereof), we hypothesize that the lack of significant associations between the two variables to be the result of our study population, as well as the limitations associated with using LVEF to represent the myocardial function. GIPS-III subjects underwent rapid PCI, thereby limiting the extent of myocardial infarction and subsequent deterioration of LV function. In doing so, this rapid PCI approach could have limited the variation in LVEF amongst these patients, which could explain the lack of an association between LVEF and TMAO [eGFR stratification showed that such associations became no longer suggestive in patients with normal kidney function , thereby implying an interplay between renal dysfunction, higher TMAO values, and infarct sizes. The baseline Descriptive statistics of post-PCI medication stratified by eGFR with cut-off point 60 mL/min/1.73 m2 can be found in In this investigation, we outlined the temporal course of TMAO in the post-PCI context of STEMI patients and associations between TMAO levels and infarct sizes. These associations were accentuated in terms of significance in patients with impaired renal function (eGFR < 90 mL/min/1.73 m


Cardiac evaluations, including cardiovascular magnetic resonance (CMR) imaging and biomarker results, are needed in children during mid-term recovery after infection with SARS-CoV-2. The incidence of CMR abnormalities 1–3 months after recovery is over 50% in older adults and has ranged between 1 and 15% in college athletes. Abnormal cardiac biomarkers are common in adults, even during recovery.We performed CMR imaging in a prospectively-recruited pediatric cohort recovered from COVID-19 and multisystem inflammatory syndrome in children (MIS-C). We obtained CMR data and serum biomarkers. We compared these results to age-matched control patients, imaged prior to the SARS-CoV-2 pandemic.CMR was performed in 17 children  and 29 age-matched control patients without SARS-CoV-2 infection. Cases were recruited with symptomatic COVID-19  or MIS-C  and studied an average of 2 months after diagnosis. All COVID-19 patients had been symptomatic with fever (73%), vomiting/diarrhea (64%), or breathing difficulty (55%) during infection. Left ventricular and right ventricular ejection fractions were indistinguishable between cases and controls . Mean native global T1, global T2 values and segmental T2 maximum values were also not statistically different from control patients (p ≥ 0.06 for each). NT-proBNP and troponin levels were normal in all children.Trial Registration Not applicable.Children prospectively recruited following SARS-CoV-2 infection had normal CMR and cardiac biomarker evaluations during mid-term recovery.  Epidemiologic evidence gathered during the Coronavirus Disease 2019 (COVID-19) pandemic demonstrates that children infected with SARS-CoV-2 are relatively spared from severe disease compared to adults  are needed” . We respWhile we can only speculate how our results may have differed with a more comprehensive protocol including administration of gadolinium-based contrast agent, native T1 and T2 mapping have excellent diagnostic performance for myocardial injury in adult and pediatric myocarditis , 17, outOur study is limited by small sample size. Additional studies are needed to exclude the possibility of a low frequency of long-term cardiac complications in children. In our study, the indexed RV and LV volumes in study patients were only slightly larger than in controls. There are two possible reasons for these mild discrepancies. First, controls were drawn from a population that was evaluated to exclude cardiac disease. This is a common methodology in pediatric CMR studies, but has a potential drawback: although none of the control patients received a diagnosis of cardiac disease, the incidence of subtle myocardial abnormalities may be higher in this group than in a randomly selected population cohort. Our control group probably represents the upper bound of normal LV and RV findings that are present in the population. To minimize this possibility, we verified that none of the case patients exceeded normative data previously established with a larger control group . Second,Our study did not identify CMR abnormalities following SARS-CoV-2 infection in older children an average of 2 months into recovery from symptomatic disease.


An association has been identified between mitral valve prolapse (MVP) and sudden cardiac arrest (SCA), and ventricular arrhythmias (VA). This study aimed to elucidate predictive factors for SCA or VA in MVP patients.MVP patients who underwent cardiac magnetic resonance (CMR) were retrospectively included. Patients with other structural heart disease or causes of aborted SCA were excluded. Clinical characteristics  and electrocardiographic , echocardiographic , and CMR  parameters were analyzed.P = 0.004], LGE volume  and LGE proportion  were independently associated with higher risk of SCA or VA in MVP patients together with systolic curling motion in each model.Of the 85 patients , seven experienced SCA or VA. Younger age and wide QRS complex were observed more often in the SCA/VA group than in the no-SCA/VA group. The SCA/VA group exhibited lower RVSP, more systolic curling motion and LGE, greater LGE volume, and higher LGE proportion. The presence of LGE [hazard ratio (HR), 19.8; 95% confidence interval (CI) 2.65–148.15; The presence of systolic curling motion, high LGE volume and proportion, and the presence of LGE on CMR were independent predictive factors for SCA or VA in MVP patients. Mitral valve prolapse (MVP), a common valvular heart disease affects 2–3% of the general population , 2. AlthCMR images can be used to analyze the myocardial composition and identify, for example, myocardial fibrosis. Several studies have reported that late gadolinium enhancement (LGE) distribution on CMR is associated with ventricular arrhythmia (VA) , 8–10. RIn this multicenter retrospective study, we aimed to evaluate the risk factors for SCA or VA in MVP patients. Furthermore, we aimed to elucidate usefulness of CMR for prediction of SCA or VA in MVP patients.This was a multicenter retrospective cohort study. The study design was approved by the institutional review board (IRB) (IRB number: 4-2019-0747 and 2019-1151) and the study was conducted in accordance with the Declaration of Helsinki. The need to obtain informed consent from the patients and the need for review by a critical event committee were waived by the IRB due to the retrospective nature of this study and the absence of patient identification data presented.Among patients who were diagnosed with MVP on echocardiography, total 117 patients (aged ≥ 18 years) patients who underwent CMR for any reasons from January 2000 to June 2019 in three university hospitals were retrospectively included. The exclusion criteria were as follows: (1) presence of concomitant structural heart disease other than MVP; (2) presence of possible causes of SCA other than MVP; (3) CMR performed after mitral valve surgery; (4) significant (intervention-requiring) coronary artery disease.In all patients, a 12-lead Electrocardiography (ECG) was performed using standard methods. The ECG of each patient at the time of diagnosing MVP was reviewed, and their ECG parameters  were obtained.Following standard methods, transthoracic echocardiography was performed in all patients. Echocardiography at the initial diagnosis of MVP was analyzed. The criteria for the diagnosis of MVP included an abnormal systolic valve motion of the mitral leaflet into the left atrium (LA) (≥ 2 mm beyond the annulus) on transthoracic echocardiography . The graIn institution 1, CMR was performed either using 1.5-T scanner  or 3.0-T scanner . In institution 2, it was conducted using a 1.5-T system  and a 32-channel cardiac coil. In institution 3, 1.5-T systems  were used. The CMR protocol of each institution was previously described in detail by studies conducted in each center –19. ECG-All CMR images were analyzed off-line using a dedicated software program . The left ventricular (LV) ejection fraction (EF), LA volume index, right ventricular ejection fraction (RVEF), LV and RV end-diastolic (EDV) and systolic (ESV) volume index, valvular prolapse distance, presence of MAD and systolic curling motion, and LGE volume and proportion were all estimated from the CMR images. From short-axis cine images, the LV and RV volumes and EF were measured using a semi-automatic segmentation in the software, and all volume measurements were normalized to the body surface area. The papillary muscles and trabeculations were included in the LV volume. MAD was defined as a separation between the LA-valve junction and the atrial aspect of the LV free wall and systolic curling motion was defined as an unusual systolic motion of the posterior mitral ring on the adjacent myocardium. The length of MAD was measured from the LA wall-mitral valve leaflet junction to the top of the LV wall during end-systole in long-axis cine images , 20. ProMedical records, ECG, echocardiography at the time of diagnosing MVP and CMR images were reviewed. Clinical characteristics  were acquired from the medical records. SCA was defined as abrupt cessation of cardiac function resulting in loss of effective circulation when witnessed or within 24 h from being last seen in healthy state when unwitnessed. The VA included ventricular fibrillation and sustained or non-sustained ventricular tachycardia (NSVT) on a single- or 12-lead ECG, Holter monitoring, or treadmill test. We confirmed SCA and VA using medical claims and records retrospectively. Patients were classified based on the presentation of SCA or VA into two categories, as follows: the SCA/VA group and no-SCA/VA group. Baseline characteristics, ECG , echocardiographic , and CMR  findings were compared between the groups. Associations of baseline characteristics and ECG, echocardiographic, and CMR findings with SCA or VA were analyzed.Baseline characteristics were analyzed using descriptive statistics. Continuous variables were presented as median with inter-quartile range for non-normally distributed variables, whereas categorical variables were presented as frequency and percentages. Continuous and categorical variables were compared using Wilcoxon rank-sum test and Fisher’s exact test, respectively. A Cox regression analysis was used to identify the predictors of SCA or VA in the MVP patients and estimate the hazard ratios (HRs), 95% confidence intervals (CIs), and p-values. The variables selected for the multivariable analysis were those with a p-value of < 0.05 in the univariable analysis. When there was multicollinearity among variables, we used the more significant variable for adjustment in the multivariable Cox regression analysis. LGE-related parameters, including presence of LGE, LGE volume, and LGE proportion, were separately analyzed in three different models because there was multicollinearity among the three variables. Statistical Package for the Social Sciences version 25.0 for Windows  and R software version 3.6.2  were employed in the analysis of data.A total of 117 MVP patients  who underwent CMR were screened. Thirty-two patients were excluded due to congenital heart disease, ischemic cardiomyopathy and prior mitral valve surgery. Following this, 85 patients  were finally included; of whom, SCA occurred in 5 patients, sustained ventricular tachycardia occurred during treadmill test in 1 patient, and NSVT occurred during treadmill test and Holter monitoring in 1 patient during the 7.2 (3.9–9.1) years’ follow-up.Baseline characteristics of patients in the SCA/VA and no-SCA/VA groups are presented in Table Echocardiographic and CMR findings of patients in the SCA/VA and no-SCA/VA groups are presented in Table Brief characteristics and LGE findings of seven patients who experienced SCA or VA and of four patients in whom LGE was identified on CMR without SCA or VA are presented in Table P = 0.024), presence of systolic curling motion , and presence of LGE  were independently associated with SCA or VA (Table P = 0.006) and LGE proportion  were independently associated with SCA or VA in model 2 and model 3, respectively. QRS duration and systolic curling motion were consistently associated with SCA or VA  MVP patients who experienced SCA or VA were younger and had wider QRS complex, lower RVSP, more frequent systolic curling motion and LGE on CMR, greater LGE volume, and higher LGE proportion than those who did not experience SCA or VA, and (2) the presence of LGE, high LGE volume and proportion, and systolic curling motion on CMR were independently associated with SCA or VA in MVP patients.Previous studies have reported that young age, female sex, severe valve dysfunction, bileaflet MVP, ventricular ectopy, and LGE on CMR are possible risk factors for SCA in patients with MVP –6, 23. ILGE on CMR may indicate focal myocardial fibrosis, which can be a substrate of VA , 25. TheSeveral attempts have been conducted regarding the prediction of SCA or VA with CMR with advancements in CMR technology. In a previous study, the extent of LGE was reported as a strong predictor of recurrent adverse events among SCA survivors . This coPast studies have reported a relationship between T wave inversion in the inferior leads, RBBB, and frequent ventricular ectopy, and SCA risk in MVP patients , 31. TheA probable association has been proposed between the severity of MR, myxomatous degeneration of the mitral valve leaflets, involvement of both leaflets, and ruptured chordae tendinae and SCA. In the present study, the severity of MR and involvement of both leaflets were not statistically significant. Since this study was conducted in tertiary medical centers, biased subjects, together with small number of events, could be a reason of different results compared to previous study.There were several limitations to this study. First, as it was a retrospective cohort study, there could be some missed variables in this study which were previously reported as possible predictors for SCA/VA. Furthermore, since data collection and evaluation depended on the medical records and imaging review, there were some limitations to obtain clear information about the situation of patients. Second, the numbers of the patients and event numbers were small. That could be a cause of statistical limitations to analyze risk factors. In some variables that showed no statistical significance, type II error might occur due to the small number of patients. Third, selection bias might be involved in this study design. As this study was conducted in tertiary medical centers, MVP was advanced in the most patients. Moreover, since this study included the only MVP patients who had undergone CMR, these patients would represent a higher risk subset. This biased selection could be a reason for the relatively higher prevalence of SCA or VA  reported in this study than in the general population. Fourth, the LGE analysis was performed on CMR images obtained using 1.5 T and 3.0 T scanners; differences in resolution could have compromised LGE quantification. Accordingly, analysis of LGE was performed as core lab analysis by one radiologist. Fifth, in this study, NSVT was classified alongside SCA. The association between episodes of NSVT and SCA remains unclear. However, it has been reported that patients with MVP and NSVT were more likely to have inducible sustained ventricular tachycardia with programmed stimulation compared with a structurally normal heart . In addiThe presence of systolic curling motion, high LGE volume and proportion, and the presence of LGE on CMR were identified as independent predictive factors for SCA or VA in MVP patients.


A variety of different nanomaterials (NMs) such as microbubbles (MBs), nanobubbles (NBs), nanodroplets (NDs), and silica hollow meso-structures have been tested as ultrasound contrast agents for the detection of heart diseases. The inner part of these NMs is made gaseous to yield an ultrasound contrast, which arises from the difference in acoustic impedance between the interior and exterior of such a structure. Furthermore, to specifically achieve a contrast in the diseased heart region (DHR), NMs can be designed to target this region in essentially three different ways . The localization and resolution of ultrasound imaging can be further improved by applying ultrasounds in the DHR, by increasing the ultrasound frequency, or by using harmonic, sub-harmonic, or super-resolution imaging. Local imaging can be achieved with other non-gaseous NMs of metallic composition  by using photoacoustic imaging, thus widening the range of NMs usable for cardiac applications. These contrast agents may also have a therapeutic efficacy by carrying/activating/releasing a heart disease drug, by triggering ultrasound targeted microbubble destruction or enhanced cavitation in the DHR, for example, resulting in thrombolysis or helping to prevent heart transplant rejection. Ultrasound is commonly used to obtain an image of an internal organ or to examine a pregnant woman. It displays certain advantageous properties such as a relatively modest cost, an absence of toxicity due to the use of non-ionizing radiations and wide availability . CertainIn this review, the different types of nanomaterials that can be used for the treatment and detection of heart disease, are first presented. They include microbubbles, nanobubbles, nanodroplets, biodegradable polymeric nano-capsules, hollow nanometric silica structures (HNSS), and magnetic nano-structures embedded within the pores of silica meso-structures. Second, the added value of ultrasound contrast agents in ultrasound imaging is presented. The resolution of ultrasonography, which is commonly used to detect various dysfunctioning heart parts, can be improved by using an ultrasonic wave for the excitation and detection of MB. On the one hand, such improved resolution can come from a refinement of the types of ultrasound beam that is employed, e.g., by using harmonic/sub-harmonic imaging or by increasing the frequency of the applied ultrasound or the speed of detection of the ultrasound beam. On the other hand, the contrast can be enhanced in the presence of MB, whose gas content can locally create a difference in acoustic impedance between the interior of MB and the surrounding heart tissue . To ensuThe properties of the different types of nanomaterials, which have been described as suitable ultrasound theragnostic contrast agents for the treatment or diagnosis of heart diseases, are presented in 6 for Sonovue [3F8 for cationic MBs [Microbubbles, which are spheroidal vesicles, are the most widely described contrast agents for use in imaging and treatment of cardiac diseases. While the MB coating material can be made of lipids or polymers or denatured proteins , those u Sonovue , or C3F8onic MBs , to the onic MBs  or an aconic MBs  allow thonic MBs . Third, onic MBs . Fourth,onic MBs , thus beonic MBs , restoreonic MBs , downregonic MBs , or restonic MBs . It has onic MBs . Throughonic MBs . UTMD caonic MBs . In addionic MBs . An addionic MBs ,55. TAs,onic MBs . Deng etonic MBs  provide Overall, nanobubbles (NBs) are smaller than microbubbles (MBs), in other words, mostly below 1 µm, while MBs are generally larger than 1 µm. While NBs are made of a coating and internal compartment with a similar composition to MB , the NB mode of action differs from that of MBs in that NBs can in principle more easily target heart compartments passively than MB due to their smaller sizes. Unlike MB, NB do not appear to act by a mechanism of bubble destruction similar to UTMD for the treatment of heart diseases. Instead, NBs can be associated with FGFP1 localized on their surface, resulting in the downregulation of CTGF, Casp-3 mRNA , and enc2Cl2),) which can transform into MBs under the application of ultrasound through a mechanism called acoustic droplet vaporization (ADV). As for NBs and MBs, NDs can be associated with molecules of interest for the treatment of heart diseases such as primary cardiomyocytes (PCMs) or 17β-estradiol (E2), which are drugs recommended for cardiac hypertrophy treatment [Nanodroplets (NDs) are nanometric structures typically consisting of an external layer , and an internal core  encapsulating a natural active principle (lychnopholide) recommended for the treatment of parasitic diseases were used to protect the organism against a sustained/continuous exposure of the organism to lychnopholides, and hence to prevent the well-known cardiac toxicity of lychnopholides . Thus, NHollow nanometric silica structures (HNSS) were designed with a size of 385 nm and an internal compartment content made of perfluorinated compounds to yield an ultrasound contrasting effect. Furthermore, they were associated with an antibody targeting hs-cTnI, which is a well-known marker of myocardial damage, thus allowing the detection by ultrasound imaging of acute myocardial infarction (AMI) following intravenous injection of HNSS to rats . HNSS arFinally, it is possible to take advantage of the properties of certain magnetic nanoparticles such as those composed of iron oxide, which can be grown inside the pores of silica meso-structures, hence increasing the stability of such structures and enabling them to act as bi-modal contrast agents  . In addi3O4 NPs were used to target myocardial infarction in rats under magnetic field application, further helping these rats to recover their normal cardiac function [Nanoscale contrast agents offer the advantage of being able to target regions of the diseased heart, essentially through three methods: passive, active, and magnetic targeting, as illustrated in function .Different contrast agents can be used to enable local imaging using ultrasound, as presented for photo-acoustic and ultrasonography in The benefit of nanomaterials in detecting certain damaged or abnormal parts of the heart was highlighted by imaging carotid intima-media thickness (IMT) and plaques, which can preclude cerebrovascular events using either B-mode ultrasound or contrast enhanced ultrasound with MBs. In over 175 patients, it appeared that IMT and plaques were better visualized with contrast enhanced ultrasound (CEUS) than with B-mode ultrasound, suggesting that CEUS can be more efficient in detecting these heart abnormalities than the conventional B-mode . In echoFor MBs used or occurring in two different ways  for ultrasound frequencies between 15 and 30 MHz , and ultPC shell  should bIn addition to HFUS/UHFUS, ultrasound super-resolution (USR) has been introduced to improve the resolution of traditional ultrasound imaging techniques whose spatial resolution is insufficient to visualize heart regions of interest such as the angiogenic vasa vasorum, which can highlight atherosclerotic plaque progression ,81. USR 2 [In addition to the methods described above that solely use US for excitation and detection, it is possible to rely on imaging methods that combine US detection with another type of radiation such as a laser to trigger the excitation of a nanometric US contrast agent (CA) ,83. Repl2  or vario2 . The com2 . Second,2 . Third, 2 . Fourth,2 . Fifth, 2 . Sixth, 2 . Seventh2 , a dual 2 , using p2  by usingThe various therapeutic activities of nanoscale contrast agents exposed to ultrasounds are summarized in Sonothrombolysis, which is carried out by treating thrombi with a combination of ultrasound and nanoscale ultrasound contrast agents (CA), presents a number of advantages compared to the use of ultrasound alone. First, CA can help transport thrombolytic agents such as t-PA or urokinase to the blood clot . Second,Sonodynamic therapy (SDT) is a method, which originates from photodynamic therapy (PDT) , but useIt therefore appears that NMs used in combination with ultrasound can improve the detection and treatment of many of the previously mentioned heart diseases. For example, mesenchymal stem cells (MSC), which are primarily found in the bone marrow and therefore also designed by bone marrow mesenchymal stem cells (BMSC), can be transplanted to damaged parts of the heart  to favor the regeneration and repair of such regions . Thus, aConcerning human embryonic stem cell cardiomyocytes (hESCC), they can potentially treat heart failure by enabling heart regeneration. To make this approach successful, hESCC cell transplantation should be monitored by using, for example, polymeric nanoparticles acting as PA contrast agents that can be used to follow hESCC-CM transplantation in living mouse hearts .The success of a stem cell-based heart disease treatment relies in large part on the use of an efficient imaging method to monitor stem cell transplantation. Thanks to nanomaterials, this can be achieved either by using contrast enhanced echography with NMs , or PA iFurthermore, angiogenesis can occur or be triggered during/following a heart disease for the benefit of the patient . For exHeart transplant, which is carried out when patients have reached the latest stage of heart failure/disease, can also benefit from a treatment involving MBs exposed to ultrasound, as shown by detecting the presence of acute cardiac transplant rejection (AR) with MB targeting intercellular adhesion molecule-1 (ICAM-1) , or T lyHypertrophic cardiomyopathy (HCM) is characterized by an increase in heart muscle thickness, resulting in the heart acting as a less efficient pump. It was shown that MBs targeting the microRNA inhibitor in the presence of UTMB could suppress cardiac hypertrophy in mice .Atherosclerosis, which can cause heart failure, is characterized by the deposition of a lipid plaque on the walls of the arteries. UTM can be used to deliver IL-8 antibodies, reduce the inflammatory response, and increase plaque stability in a rabbit atherosclerosis model . MBs canA thrombus, also called a blood clot, results from blood coagulation in heart vessels. It can decrease the amount of blood flowing from or toward the heart. MBs combined with the application of ultrasound can be used to dissolve/destroy thrombi through the delivery of thrombolytic drugs, mechanical stress induced by acoustic cavitation, or UTMD occurring/performed in the region of the thrombi either by applying ultrasound in this region or by using MB ligands such as RGDS tetrapeptide that target thrombi. These methods were able to achieve complete recanalization of the blocked artery, under possible local monitoring of thrombus destruction using highly contrasting MBs .Cardiomyopathy, which is characterized by the presence of a dysfunctional heart muscle preventing the heart from properly pumping blood to other parts of the body, is described as occurring in patients suffering from diabetes or treated with certain drugs such as doxorubicin, ,46,111. In-stent restenosis is characterized by the narrowing of a blood vessel following stent implantation, leading to the slow-down or blockage of blood flow and to heart attack in the worst-case scenario. To prevent such adverse events from occurring, vascular polymeric nano-patches embedding anti-restenotic drugs can be used to release such active principles locally in the DHR under ultrasound application .Cardiovascular diseases (CVD) were responsible for the death of 18 million people in 2019, representing the cause of one third of all global deaths , hence nNM biosafety, which is a prerequisite for NM human administration, depends on several interdependent factors such as NM administration route, physico-chemical properties or compositions . Therefo


Angiotensin-converting enzyme (ACE) activity was about five times higher in the anterior LV wall at six weeks than that in sham animals. Angiotensin-converting enzyme 2 (ACE2) activity roughly doubled in post-ischemic LVs. These increases in ACE and ACE2 activities were effectively mitigated by rRIC. Ca2+-sensitivities of force production (pCa50) of LV permeabilized cardiomyocytes were increased at six weeks after MI induction together with hypophosphorylation of 1) cardiac troponin I (cTnI) in both LV regions, and 2) cardiac myosin-binding protein C (cMyBP-C) in the anterior wall. rRIC normalized pCa50, cTnI and cMyBP-C phosphorylations. Taken together, post-ischemic LV remodeling involves region-specific alterations in ACE and ACE2 activities together with changes in cardiomyocyte myofilament protein phosphorylation and function. rRIC has the potential to prevent these alterations and to improve LV performance following MI.Post-ischemic left ventricular (LV) remodeling and its hypothetical prevention by repeated remote ischemic conditioning (rRIC) in male Sprague–Dawley rats were studied. Myocardial infarction (MI) was evoked by permanent ligation of the left anterior descending coronary artery (LAD), and myocardial characteristics were tested in the infarcted anterior and non-infarcted inferior LV regions four and/or six weeks later. rRIC was induced by three cycles of five-minute-long unilateral hind limb ischemia and five minutes of reperfusion on a daily basis for a period of two weeks starting four weeks after LAD occlusion. Sham operated animals served as controls. Echocardiographic examinations and invasive hemodynamic measurements revealed distinct changes in LV systolic function between four and six weeks after MI induction in the absence of rRIC  decreased from 52.8 ± 2.1% to 50 ± 1.6%, mean ± SEM,  Although rapid reperfusion has dramatically reduced short-term mortality of patients with acute myocardial infarction (MI), current management strategies cannot prevent the development of post-ischemic chronic heart failure in a significant proportion of MI cases . Consequβ-adrenergic cascade) implicate roles for over-activated neuro-humoral signaling in myocardial remodeling  and contractile myofilaments. Here we found that Ca2+-sensitivity of force production (pCa50) was significantly increased in permeabilized cardiomyocytes in both the anterior and in the inferior regions of the post-ischemic LV chamber. An increase in pCa50 is considered as a hallmark of myocardial remodeling and HF in humans and its animal models ) expressed in pCa units were estimated by –lg [Ca2+]. The pCa of the activating and relaxing solutions was 4.75 and 9.0, respectively. When a steady force level had been reached, a rapid release–restretch maneuver (30 ms) was applied to determine the baseline of the force generation and hence the Ca2+-activated total force . Ca2+- independent passive force (Fpassive) of the cardiomyocytes was measured by shortening to 80% of the original preparation length at pCa 9.0 for 8 s. The active force (Factive) was calculated as a difference of the Ftotal and Fpassive. Maximal activation at pCa 4.75 was used to determine the maximal Ca2+-activated isometric force (Fmax), while activations with intermediate [Ca2+] (pCa 5.4– 7.0) yielded the pCa–isometric force relationship. Isometric forces at submaximal [Ca2+] normalized to Fmax and fitted to a modified Hill-equation  and to determine the Ca2+-sensitivity of force production (pCa50). Original forces of every individual cell were normalized to myocyte cross sectional-area, calculated by the width and height of the cardiomyocyte. Absolute force values of Fmax, Factive, and Fpassive were expressed in kN/m2. LV samples from four different hearts (n = 8 cardiomyocytes from each heart) were used in the force measurements.LV tissue samples from anterior and non-infarcted remote inferior areas were mechanically disrupted in ISO and membrane-permeabilized by 0.5% Triton X-100 detergent in ISO at 4°C. Myocyte-sized preparations were mounted with silicone adhesive  to two stainless steel insect needles, which were connected to a sensitive force transducer  and to an electromagnetic high-speed length controller  in ISO at 15°C. Subsequent cardiomyocyte isometric force generation was recorded at sarcomere length of 2.3 μm and analyzed by LabVIEW software . Cardiomyocyte Caw/v) sodium dodecyl sulfate (SDS), 75 mM DTT, 50 mM Tris-HCl, pH 6.8, 10% (v/v) glycerol, bromophenol blue, 40 µM leupeptin and 10 µM E-64) for 45 min by vortex procedure. After centrifugation , protein amount of supernatant was estimated by dot–blot technique and set to 2 mg/mL concentration correlating the sample to bovine serum albumin (BSA) standards. Agarose- strengthened 2% and 4% SDS-polyacrilamide gels were used to separate N2B titin (~3200 kDa) and cardiac myosin-binding protein C (cMyBP-C). Overall phosphorylation levels of titin and cMyBP-C proteins were assessed by Pro-Q® Diamond phosphoprotein staining  according to the manufacturer’s protocol, while total protein levels were assayed by Coomassie blue .Cardiomyocytes were isolated and permeabilized from frozen LV tissue samples and were homogenized in sample buffer  phosphorylation Western immunoblot assays, proteins were separated in 12% polyacrilamide gels, then transferred to nitrocellulose membrane and probed with PKA- [Ser-22/23 (1:1000)], or PKC-dependent primary  and secondary antibodies . Proteins were detected by enhanced chemiluminescence and documented by MF-ChemiBIS 3.2 gel documentation system . All biochemical analyses were performed on 4–6 samples/groups.t-test when appropriate. p values of <0.05 were considered statistically significant.Data are expressed as mean ± SEM. Statistical analysis was performed with GraphPad Prism 6.0 software . Western immunoblot assays were performed in triplicate. Signal intensities of protein bands were quantified by using the ImageJ  and Magic Plot  software. Differences were evaluated by one-way ANOVA followed by Bonferroni post hoc test or Students’ paired