Early identification for heart failure (HF) may be useful for disease modifying treatment in order to reduce heart disease progression or even to reverse it. In our previous studies, we have revealed a group of heat shock proteins (HSPs) which might be related to neonatal rat cardiomyocyte hypertrophy by proteomic approach. Here, we confirm that HSPs, including HSP27 and HSP70, altered in the early stage of cardiac remodeling in vivo animal model. Furthermore, plasma concentrations of those HSPs and their potential screening value were evaluated at different stages in 222 patient subjects. Plasma HSP27, HSP70 and HSP90 were measured using enzyme-linked immunosorbent assay. Results indicate that HSP70 was positively correlated to the severity (progression) of HF . The area under the rate of change (ROC) curve was 0.601 (p = 0.017) in patients with stage B HF and 0.835 (p<0.001) in those with stage C HF. However, HSP27 and HSP90 did not display significant changes in any stage of HF in this study. Taken together, plasma concentrations of HSP70 elevated with the progression of HF and might act as a potential screening biomarker for early diagnosis of HF. Cardiovascular diseases (CVDs) are major causes of mortality in the world. As a final stage of CVDs, heart failure (HF) becomes more prevalent year by year. It is therefore very important for the early warning, early diagnosis and treatment of heart failure. In 2005 the American College of Cardiology (ACC)/American Heart Association (AHA) updated their guidelines for the management of chronic HF (CHF) and identified four key stages of HF in patients . Among patients without signs or symptoms of HF, those at high risk of HF were defined as stage A, and those who had structural heart disease were designated as stage B. Stage C included patients with current or past symptoms of HF, and stage D designated patients with truly refractory HF. Due to the lack of a screening strategy for detection, when diagnosed HF in hospital, the patients had always developed into the stage C or even stage D. An adequate screening test for early detection of stage B patients might greatly improve HF survival.Originally demonstrated in Drosophila, the induction of heat shock proteins (HSPs) in response to elevated temperature is observed in many organisms, ranging from prokaryotic bacteria such as Escherischia coli to mammals including human. HSPs are constitutively expressed, but expression is up-regulated during pathophysiological stress In our previous studies, we have revealed a group of HSPs which might be related to neonatal rat cardiomyocyte hypertrophy by proteomic approach All study protocols conformed to the Animal Management Rules of China . All experiments were approved by the Committee for Ethics of Animal Experiments and were conducted in accordance with the Guidelines for Animal Experiments, Peking University Health Science Center. Ten-week-old male BALB/c mice were obtained from the Animal Department of the Peking University Health Science Center.The isoproterenol-induced cardiac hypertrophy was carried out by infusing isoproterenol  in vivo using subcutaneously implanted micro-osmotic pumps . In brief, 10-week-old male Balb/c mice were anesthetized and implanted with micro-osmotic pumps and isoproterenol was delivered continuously at a rate of 5 mg/kg/day. The control mice received vehicle (100 µmol/L ascorbic acid). After 3, 7, 14 and 84 days, the mice were sacrificed by cervical dislocation after deep anesthesia with 2% isoflurane and the ratios of heart weight to body weight (HW/BW) and tibia length (HW/TL) were determined.Echocardiographic analysis Cardiac hypertrophy and function were assessed by echocardiography before and after isoporterenol infusion using a Vevo 770TM Imaging System  equipped with a 30-MHz microprobe under anesthesia with 1.5% isoflurane allowing spontaneous breathing.Cell samples were lysed in 150 mL buffer containing 20 mM Tris-HCl (pH 7.4), 100 mM NaCl, 10 mM sodium pyrophosphate, 5 mM EDTA, 50 mM NaF, 1 mM sodium vandate, 0.1% SDS, 10% glycerol, 1% Triton X-100, 1% sodium deoxycholate, 1 mM leupeptin, 0.1 mM aprotinin and 1 mM PMSF. Protein concentration was estimated with a BCA protein assay kit . Proteins were separated on 10% SDS-polyacrylamide gels and then electrophoretically transferred to nitrocellulose membranes . The sheets were analyzed with antibodies according to the supplier’s protocol and visualized with peroxidase and an enhanced-chemiluminescence’s system . The following antibodies were used in this study: anti-HSP 27 , anti-HSP90 , anti-prohibitin anti-HSP 70 , anti-eIF-5 . The films were then scanned with a calibrated densitometer and images were processed by PDQuest software.All studies were approved by the Committee for Ethics of Peking University Health Science Center. Each patient who was enrolled in this study has signed the informed consent.Patients were selected from the department of cardiology at the Peking University Third Hospital  over the period July 2007 to April 2011. A total of 222 participants were divided into four groups composed of the different stages of HF Stage A (n = 76) included hypertensive patients (n = 56) according to the 2007 European Society of Hypertension (ESH)/European Society of Cardiology (ESC) hypertension guidelines Stage B (n = 68) included patients with old myocardial infarction  or those who had structural heart disease (n = 22) Stage C (n = 40) recruited previously symptomatic and currently asymptomatic CHF patients according to the ACC/AHA guideline The control (Cont) group (n = 38) included healthy volunteers without HF risk factors, cardiac structural lesion or HF symptoms.Patients with acute myocardial infarction during the preceding 12 weeks, impairment of renal function or liver function, systemic inflammatory disease, infectious disease, cancer, acute cerebral infarction, pregnancy or who were using steroids that might affect the HSPs’ level were excluded.Fasting blood samples were drawn from antecubital vein of the patients and collected into evacuated EDTA tubes in the morning. Plasma samples were obtained within 30 min of collection, by centrifugation at 3000 g for 15 min at 4°C. To avoid repetitive freeze-and-thaw cycles, each sample was divided into seven to nine aliquots, immediately frozen, and stored at −80°C for analysis. Plasma HSP27, HSP70, HSP90 levels were determined by sandwich enzyme-linked immunosorbent assay (ELISA) with commercially available kits  according to the manufacturer’s instructions. The sample was analyzed double-blindly at Sun Biomedical Technology (Beijing) Co.Ltd. Plasma NT-proBNP concentrations were measured by electrochemical luminescence methods. Levels of creatinine, uric acid, white blood cell count and percentage of neutrophils were evaluated at the central chemistry laboratory of Peking University Third Hospital. Creatinine clearance was calculated according to the Cockcroft and Gaultequation (Matz2002).Each patient underwent echocardiography lying in the left decubitus position at the time of study, entry using a GE-VingMedVechocardiographic machine (Vivid 7) with a 3.3-MHz multiphase array probe. The echocardiographic techniques and calculation of different cardiac dimensions and volumes were performed according to the guidelines of the American Society of Echocardiography . Left ventricular ejection fraction (LVEF) was obtained using a modified biplane version of Simpson’s method with apical two- and four-chamber views. These studies were carried out by experienced cardiologists.The Kolmogorov–Smirnov test was used to test for normal distribution of continuous variables. Variables with two groups were compared with the Student’s t-test. One-way ANOVA was used for comparing data for more than two groups; Student–Newman–Keuls method and the Tamhane method were used for homogeneous and non-homogeneous subsets, respectively. Proportions were compared using the χ2 test. Parametric correlation employed the Pearson correlation coefficient and the Spearman test was used for non-parametric correlation. Multiple linear regression analysis was used to identify factors that were independently associated with HSPs level. The cut-off concentration for HSPs was selected to yield the highest possible Youden Index score (sensitivity+specificity–1). Te area under the receiver-operating-characteristic (ROC) curve for HSPs was calculated. All analyses involved use SPSS 17.0 . A p-value<0.05 (two-tailed) was considered statistically significant. Data were expressed numerically (as a percentage), as a median (interquartile range) or mean±standard deviation (SD) as appropriate.2 vs. 258.2±17.1 µm2 at 3 days; 452.5±38.8 µm2 vs. 268.7±32.0 µm2 at 7 days; 489.3±68.4 µm2 vs. 270.5±5.71 µm2 at 14 days; 498.4±5.48 µm2 vs. 289.2±30.1 µm2 at 84 days, Mice receiving isoproterenol (ISO) infusion exhibited a significant increase in end-diastolic left ventricular posterior wall thickness  compared with sham at 3 days , 7 days , 14 days  and 84 days , left atrial pressure . However, no relationship was found between HSP70 and left ventricular ejection fraction.NT-proBNP is a well-accepted index that reflects left ventricular function. In the present study, the sensitivity and specificity of NT-proBNP and HSP70 were analyzed and compared. NT-proBNP showed positive correlation to the severity of heart failure . On another hand, the concentrations of HSP70 and NT-proBNP were also positively correlated . The correlation remained  still significant by excluding the confounding factors such as age and creatine when we excluded the factors such as age, creatine clearance. However, the correlation between them lost significance when the factor of heart failure stages was excluded , which implied that the relationship between NT-proBNP and HSP70 depended on the stage of heart failure . In otheROC curves of HSP70 or NT-proBNP diagnosing stage B or C of HF was investigated. ROC curves of HSP70 and NT-proBNP diagnosing stage B HF are shown in It is well known that the level of HSPs is usually induced upon stresses. In the present study, we found that the expressions of HSP70 and HSP27 but not HSP90 increased during cardiac hypertrophy in mice, showing a selectively altering profile. In addition, the expressions of the two HSPs appeared to increase from the very early phase (at 3 days) in response to isoproterenol. The findings gave us a clue: the change in HSPs expressions may be developed as an effective index for early diagnosis of heart failure if it appears similar profile in patients. Thus, we then evaluated 222 patients with cardiovascular clinical or cardiographic findings. Except for control group, they were divided into three groups: (1) those at risk for development of clinical HF (such as coronary heart disease or high risk factor of coronary heart disease); (2) patients with cardiac structural abnormalities resulting from cardiac pathology ; and (3) patients with clinically identifiable HF. Patients were stratified according to ACC/AHA HF guidelines and the mean HSP level was then analyzed in this stratification. In our study, HSP70 level was positively correlated with the progression of HF. However, HSP27 and HSP90 were not observed related to HF.HSPs, known as a family of intracellular proteins with cytoprotective function, were considered as molecular chaperones essential for cell survival both in physiological and stress conditions HF is a progressive condition. In animal models overexpression of HSP70 protects the heart against damaging effects of ischemia In conclusion, based on our previous proteomic results, we have revealed that HSP27 and HSP70 were increased with the progression of cardiac hypertrophy and that HSP90 was not altered at the same time in animal cardiac hypertrophy model. In human the plasma concentration of HSP70 increased gradually with progression of ACC/AHA HF stages. However, HSP27 and HSP90 were not related to HF stages. HSP70 has potential implications for detecting stage B HF and monitoring high-risk HF patients.


Left-ventricular (LV) shape remodeling has known association with cardiac pathophysiology and dysfunction. While a prolate spheroid shape is vital for optimal cardiac function, LV dilatation and high sphericity is characteristic of cardiomyopathy. Early quantification of abnormal LV morphology may potentially guide clinical decisions to check disease progression. However a quantitative biomarker of 3D LV morphometry is found wanting in routine clinical practice as an upgrade to the rudimentary sphericity index.Spherical harmonics (SPHARM) shape descriptors were sought to quantify patient-specific LV shape. Morphometric variation from a normal LV shape was studied with application to diagnostic identification of cardiomyopathy. Cardiac MR (CMR) was employed for anatomical examination and end-diastolic LV endocardial surface models were segmented from short-axis SSFP cine scans of 11 pediatric subjects between the ages 2 and 17. Surface models were individually registered by rigid transformation and scaling to match the LV base diameter of a reference 17 year old normal LV that approximated well to a prolate spheroid. Two characteristic morphometric difference percentages (DP) were computed as a percentage of normal LV length for each case with respect to the reference normal model i.e. maximum DP (MDP) and average DP (ADP). A 16 patient cohort was used for training, comprising 10 simulated normals (ADP < 3.5 % & MDP < 13%) and 6 abnormal cases including 2 with LV hypertrophy (LVH), 3 with arrythmogenic right ventricular dysplasia (ADVD), 1 post myocardial infarction (MI). Rule-based decision trees were prepared to predict a response function defining normal vs. pathological cases using the new MDP and ADP predictors simultaneously with the conventional LV sphericity index as a third predictor, through a 3D generative clustering approach. Classification accuracy was evaluated with a 6 patient test cohort comprising 3 ARVDs, 2 LVH and 2 normal subjects.The underlying principle of this LV-base normalized diffeomorphic analysis is that LV remodeling is accompanied by heightened sphericity. This assumption was verified by the existence of positive Spearman rank correlations for sphericity with ADP (0.41) and MDP (0.28). 100% test classification accuracy was obtained using a simultaneous thresholds for MDP (>13.9%), ADP (>3.5%) and sphericity (>0.7). ARVD patients were all identified as pathologies based upon LV shape alone. Further, strong correlation (0.94) was observed between LV sphericity and age for ARVD patients.This pilot study suggests DP is a valuable biomarker in identifying cardiomyopathy. Strong correlation between sphericity and ARVD patient age combined with the excellent classification of ARVD as a cardiomyopathy by LV shape alone supports possible left-sided involvement in ARVD. Analysis with a larger cohort comprising more normal controls is warranted to validate this hypothesis.No funding sources to disclose.


Changes in pulse contour CI showed a significant correlation with changes in thermodilution CI both before  and after  CPB. Our findings demonstrated that uncalibrated semi-invasive monitoring system was able to reliably measure CI compared with transpulmonary thermodilution in patients undergoing elective coronary surgery. Furthermore, the semi-invasive monitoring device was able to track haemodynamic changes and trends.Uncalibrated semi-invasive continous monitoring of cardiac index (CI) has recently gained increasing interest. The aim of the present study was to compare the accuracy of CI determination based on arterial waveform analysis with transpulmonary thermodilution. Fifty patients scheduled for elective coronary surgery were studied after induction of anaesthesia and before and after cardiopulmonary bypass (CPB), respectively. Each patient was monitored with a central venous line, the PiCCO system, and the FloTrac/Vigileo-system. Measurements included CI derived by transpulmonary thermodilution and uncalibrated semi-invasive pulse contour analysis. Percentage changes of CI were calculated. There was a moderate, but significant correlation between pulse contour CI and thermodilution CI both before ( Estimation of haemodynamic variables such as left ventricular stroke volume and cardiac index in high-risk patients is a prerequisite for performing individual goal-directed therapy. Perioperative haemodynamic optimization and individual tailored therapy have been shown to improve patients' outcome by reducing morbidity and the length of stay on the intensive care unit –3. In clWave) with transpulmonary thermodilution (CITPTD) before and after cardiopulmonary bypass (CPB). Furthermore, we studied the ability of the semi-invasive technique for tracking haemodynamic changes and trends.The aim of the present study was to investigate the precision of CI determination based on arterial waveform analysis by a third-generation device , written informed consent for participation in the study was obtained from all patients.Fifty patients undergoing elective coronary artery bypass grafting (CABG) were studied after induction of general anaesthesia until discharge to the intensive care unit. Exclusion criteria were patients <18 years of age, a left ventricular ejection fraction ≤0.5, emergency procedures, and patients with haemodynamic instability requiring continuous pharmacologic support. Patients with intracardiac shunts, severe aortic, tricuspid or mitral stenosis or insufficiency and mechanical circulatory support were also excluded.2) and heart rate (HR) . Subsequently patients received a peripheral venous access and a radial arterial line. A FloTrac/Vigileo-system was connected to the arterial line, followed by adjustment of the transducer and input of required individual demographic data according to the manufacturer's instructions . Variables were automatically indexed to body surface area. After induction of anaesthesia with sufentanil (0.5 μg/kg) and propofol (1.5 mg/kg), orotracheal intubation was facilitated with rocuronium (0.6 mg/kg). Anaesthesia was maintained with sufentanil (1 μg/kg/h), and propofol (3 mg/kg/h) and patients were ventilated with an oxygen/air mixture using a tidal volume of 8 mL/kg ideal body weight and positive end-expiratory pressure was set at 5 cm H2O. After placement of a central venous catheter in the right internal jugular vein, a transpulmonary thermodilution catheter  was introduced in the femoral artery. The thermodilution catheter was connected to the PiCCO2 monitor (Software version 1.3.0.8).All patients were premedicated with midazolam 0.1 mg/kg orally 30 min before induction of anaesthesia. Routine monitoring was established including peripheral oxygen saturation  through the central venous line at least three times randomly assigned to the respiratory cycle. In case of a difference of ≥15%, the value obtained was discarded and the measurement repeated. Simultaneously, measurement of CIWave was performed by plotting 5 numerical values over a period of three minutes and determining the mean value. Systolic, diastolic, and mean arterial pressures as well as CVP were also recorded every 10 minutes. After induction of anaesthesia, a passive leg raising manoeuvre (PLR 1) was performed, and haemodynamic variables including CI  and stroke volume index (SVI) were recorded before, during and after PLR. Subsequently, measurements of CITPTD and CIWave were carried out every 10 minutes until the beginning of CPB (T1), which differed from patient to patient yielding different numbers of measurements in this time period. Measurements of CITPTD and CIWave were restarted 15 minutes after weaning from CPB and were obtained up to the end of the surgical intervention (T2), again yielding a different number of measurement pairs in individual patients. Immediately before discharge to the intensive care unit, a second PLR manoeuvre (PLR 2) was performed. Study design is displayed in After induction of anaesthesia, CIs is the standard deviation of the bias). For our sample size of 50 patients, we calculate a width of the 95% confidence interval of the limits of agreement of 0.51 times the SD (of bias), which is generally thought to be an acceptable narrow 95% confidence interval.All data are given as mean ± SD. Statistical comparisons were performed using commercially available statistics software . To demonstrate the relationship between sample size and the width of the confidence interval of the estimated variable, we calculated the width of the 95% confidence interval of the limits of agreement as recommended by Bland and Altman  before and after CPB. Percentage error was calculated as described by Critchley and colleagues, using the limits of agreement (2SD) of the bias divided by the mean CI values from CITPTD and CIWave. Bland-Altman plots were also performed for haemodynamic trends  before and after CPB. Changes of CITPTD < 15% were excluded from analysis as recommended by Critchley and colleagues [t-test was used to analyse significant differences of arterial pressure and systemic vascular resistance index (SVRI) related to the periods of measurement.To describe the agreement between CI−2. Mean left ventricular ejection fraction was 0.61 ± 0.07%. A total of 468 data pairs  were obtained during the study period. Haemodynamic variables are shown in Data of all 50 patients, 37 males and 13 females, were included into final analysis. Age ranged between 40 and 85 years, with a mean age of  63 ± 5  and a mean body mass index of 26.8 ± 3.5 kg·mWave and CITPTD before (T1) and after (T2) cardiopulmonary bypass (TPTD > 15% during PLR were defined as responders. We observed 24 responders during PLR 1 (51%) and 23 responders during PLR 2 (55%), respectively. There was a significant correlation between CIWave and CITPTD   at PLR 1. Correlations and Bland Altman analysis with bias, LOAs, and percentage errors for PLR before (PLR 1) and after (PLR 2) CPB are presented in There was a significant correlation between CIy bypass . CorrelaWave versus ΔCITPTD are presented in Wave versus ΔCITPTD in T1, with LOAs from −34% to +26%. After CPB (T2), correlation coefficients of changes in ΔCIWave versus ΔCITPTD again were statistically significant, with LOAs ranging from −23 to +25%  and after  CPB. No significant correlation between MAP and CIWave was observed before  and after  CPB. Unpaired t-test showed a significant difference between SVRI before and after CPB (P < 0.05).The percentage changes for ΔCI to +25% . There wMain findings of the present study are that the semi-invasive monitoring device was able to reliably measure CI compared with transpulmonary thermodilution before and after CPB. There was a weak but significant correlation between semi-invasive CI by arterial waveform analysis and systemic vascular resistance index. The semi-invasive monitoring system was able to track haemodynamic changes and trends before and after CPB.χ). With respect to rapid changes in vascular tone, the software version investigated in the present study is able to recalculate χ every 60 seconds.The semi-invasive FloTrac/Vigileo-system was developed to continuously determine CI and stroke volume by arterial waveform analysis without the need for calibration. As described elsewhere , this syMonitoring of haemodynamic variables is mostly related to invasive procedures, sometimes time-consuming, difficult to establish and associated with method-related complications and limitations, respectively . TherefoApplying the criteria as recommended by Critchley and colleagues , we regaSome limitations of our study should be noted. We investigated patients with preserved left ventricular function undergoing elective coronary artery surgery without ongoing pharmacologic support, and we excluded patients with haemodynamic instability or in shock. Therefore, our results cannot be directly transferred to patients with impaired left ventricular function or inotropic and vasoactive support.With respect to clinical relevance, several studies could demonstrate that an individual tailored therapy was associated with reduced perioperative morbidity. Determination of cardiac index continuously is an important target while performing goal-directed therapy.In conclusion, the present study could demonstrate reliable measurement of cardiac index and haemodynamic trends by semi-invasive arterial waveform analysis in patients undergoing elective coronary surgery and with preserved left ventricular function. Therefore, our results support the use of less invasive haemodynamic monitoring systems.


The increasing availability of rodent models of human cardiovascular disease has led to a need to translate noninvasive imaging techniques such as magnetic resonance imaging (MRI) from the clinic to the animal laboratory. The aim of this study was to develop phantoms simulating the short-axis view of left ventricular motion of rats and mice, thus reducing the need for live animals in the development of MRI.Cylindrical phantoms were moulded from polyvinyl alcohol (PVA) Cryogel and attached via stiff water-filled tubing to a gear pump. Pulsatile distension of the phantoms was effected by suitable programming of the pump. Cine MRI scanning was carried out at 7 T and compared with in vivo rodent cardiac imaging.Suitable pulsatile performance was achieved with phantoms for which the PVA material had been subjected to two freeze–thaw cycles, resulting in T1 and T2 relaxation time constants of 1656±124 ms and 55±10 ms, respectively. For the rat phantom operating at 240 beats per min (bpm), the dynamic range of the outer diameter was from 10.3 to 12.4 mm with the wall thickness varying between 1.9 and 1.2 mm. Corresponding figures for the mouse phantom at 480 bpm were outer diameter range from 5.4 to 6.4 mm and wall thickness from 1.5 to 1.2 mm.Dynamic cardiac phantoms simulating rodent left ventricular motion in the short-axis view were successfully developed and compared with in vivo imaging. The phantoms can be used for future development work with reduced need of live animals. Protocols typically include multiframe gradient-echo or steady-state free precession “cine” scans in standardized cardiac planes from which indices such as left ventricular (LV) volume, LV mass and ejection fraction can be evaluated. In recent years, the availability of rodent models of human disease has led to an increase in in vivo imaging studies of mice and rats. Small-animal MRI is at a less mature stage than human MRI, and recent effort has been concerned with the translation of imaging techniques from clinical systems to high-field, small-animal systems Phantoms are test devices which mimic some aspect of the behavior of tissues within the body and are used to provide test data sets for the purposes of development of new imaging techniques and for validation of measurements without need of human volunteers or experimental animals. In cardiac imaging, compensation of cardiac (and respiratory) motion, visualization of cardiac chamber motion and quantification of chamber volume are of interest. Human studies have used numerical phantoms The aim of this work was to close this gap by developing cardiac phantoms suitable for rodent MRI. The phantoms were designed to provide realistic MRI data sets mimicking LV geometry and motion in the short-axis view.22.1The main criterion was to mimic the dynamic behavior of the heart in the short-axis  view of the left ventricle at midventricular level. The phantoms should produce plausible MRI images, be of the same general dimensions as mouse and rat left ventricles, and undergo similar distension and change in wall thickness.It was not the intention to model complex rotation and shortening movements or to mimic ventricular blood flow patterns. Previous studies have used a number of materials to construct cardiac phantoms, including agarose 0 magnetic field itself For cyclic distension of the phantom, two approaches were considered, namely, local activation and remote activation. Remote activation has been used in previous studies involving connection of the chamber to a remote pump via stiff tubing 2.2Phantoms were made to resemble the LV geometries of both rat and mouse. The dimensions of the phantoms were based on measurements made on healthy adult rats and mice in our laboratory. For both phantoms, an elongated hollow cylinder with a round end was manufactured. The mould consisted of an outer cylinder (a test tube) within which was centrally placed a Perspex rod. For the rat phantom, the outer diameter and wall thickness were nominally 10 mm and 2 mm, respectively, and for the mouse phantom, they were 5 mm and 1.5 mm, respectively. The central rod was raised above the bottom of the outer tube by an amount equal to the required wall thickness. A 15% concentration of PVA  in water was used. The PVA gel was heated to 80°C–95°C in a water bath, drawn into a 10-ml syringe and then injected into the mould to a depth of 2 cm for the rat phantom and 8 mm for the mouse phantom. The gel was allowed to settle overnight to allow any air bubbles to dissipate. The moulds were subject to two, four or six freeze–thaw cycles. Each cycle consisted of cooling at 0.5°C per minute to − 20°C, maintaining the temperature for 8 h and then allowing a rise to room temperature (22°C) at a rate of 0.5°C/min. The mould was maintained at room temperature for at least 8 h prior to separation of the PVA from the mould. The finished phantoms were stored in deionized water to prevent dehydration.2.3Relaxation time constants T1 and T2 have been reported for PVA at field strengths between 1 T and 3 T 2.4The cardiac phantoms were mounted as shown in 2.5http://rsbweb.nih.gov/ij). Outer and inner myocardial borders were fitted using elliptical contours, and radially averaged diameters and wall thicknesses were determined.The rat cardiac phantom assembly was placed in the 7-T scanner equipped with a 400-mT/m gradient set, and imaged with a 72-mm ID quadrature radiofrequency coil for transmission and a four-channel phased array coil for signal reception. Scout images enabled prescription of subsequent cine gradient-echo scanning using the manufacturer's standard sequence. One or more image slices were placed in the “short-axis” plane of the phantom. Image parameters were as follows: field of view (FOV)=42 mm, matrix 128×128, slice thickness 1.5 mm, four averages and minimum echo time. Repetition time was 10 ms, and flip angle was 20°. Trigger pulses from the pump controller were used to synchronize scanning with the motion of the phantom, and the number of time frames was adjusted to fit into the period of the motion. The mouse cardiac phantom was imaged with a 39-mm ID quadrature-driven transmit/receive coil and a 1000-mT/m gradient set. Other imaging parameters were as follows: FOV=30 mm, matrix 192×192, slice thickness 1 mm, three averages, repetition time 9.5 ms and flip angle 20°. Cine cardiac images were also acquired from anesthetized, healthy adult rats  and mice  using the same imaging parameters. All animal scanning complied with UK Home Office and University of Edinburgh regulations. Cardiac dimensions were measured from each time frame of the phantom image data sets and from the midventricular slice of representative rat and mouse image data sets using ImageJ software (33.1Values of T1 measured at 7 T were 1656±124, 1411±134 and 1334±96 ms for two, four and six freeze–thaw cycles, respectively, these figures being the mean±standard deviation over the imaged slices. The corresponding values for T2 were 55±10, 48±8 and 40±6 ms.3.2Preliminary experiments showed that phantoms made with two freeze–thaw cycles gave suitable distension with the pump system and were selected for the remainder of the study. 4Left ventricular phantoms created using two freeze–thaw cycles of PVA material gave satisfactory performance compared with in vivo imaging of rats and mice.We believe that these are the highest field measurements to date of the T1 and T2 properties of PVA Cryogel. Available literature values for T1 are approximately 400 ms, 600 ms, 800 ms and 1100 ms at 1 T, 1.5 T, 1.9 T and 3 T, respectively Use of a pure sinusoidal flow from the pump resulted in eventual collapse of the phantom at “end systole,” so that an offset sinusoid was used. In practice, the amplitude and degree of offset were adjusted until the phantom operated without collapse. The use of an offset sinusoid would seem to imply an overall net flow towards the phantom. However, since no leaks were evident downstream of the pump, we conclude that the pump itself was not 100% efficient and that there was some backflow through it.The phantoms exhibited smooth cyclic behavior with suitable pump settings, and the walls were highly visible in the MR images. As can be seen from A limitation of the current phantoms is that their geometry is very simplified compared with real rodent hearts, but it is sufficient for imaging in the short-axis view routinely used in assessment of cardiac function Refinements beyond the scope of the current work could include the addition of rotation and “respiratory” motions, the incorporation of metabolites in the phantom walls for the development of MR spectroscopic techniques, and the use of a fully programmable pump to enable asymmetric timing of the cardiac cycle.5Dynamic cardiac phantoms simulating rodent LV short-axis motion were successfully developed and compared with in vivo imaging. The phantoms can be used for scanner testing and method development with reduced use of live animals.


One of the causes of septic mortality is a low cardiac output secondary to preload failure. Same patients demonstrate preload failure after aggressive volume replacement .t criteria.Ultrasound impulse-wave Doppler evaluation of transmitral flow: VmaxE, VmaxA, ejection time E,A; DT E wave, IVRT of LV. Ultrasound evaluation of end-diastolic and end-systolic LV volume, stroke volume  on Teichholz L. EDLVP = 1.06 + 15.15 × VTI peakA/VTI peakE. Coronary perfusion pressure (CPP) = EDLVP - diastolic BP. We evaluate these parameters in 34 patients (age 28.1 ± 8.0 months) with septic shock (SS) diagnosed according to Consensus 2002. Control (C) - 44 healthy children (age 40.7 ± 8.5 months). Statistical analyses with The increase of VmaxA and decrease of VmaxE in patients of SS are demonstrated. IVRT and DT are less than in control group. We evaluated a decrease in E/A proportion. EDLVP in patients was more, and CPP lower, than in controls. See Table Pediatric SS accompanied with LV diastolic dysfunction, which decreases the effectiveness of volume restoration therapy, reduces preload and cardiac output.


The degree of pulmonary hypertension is not independently related to the severity of left ventricular systolic dysfunction but is frequently associated with diastolic filling abnormalities. The aim of this study was to assess diastolic times at increasing heart rates in normal and in patients with and without abnormal exercise-induced increase in pulmonary artery pressure (PASP). Methods. We enrolled 109 patients  referred for exercise stress echocardiography and 16 controls. The PASP was derived from the tricuspid Doppler tracing. A cut-off value of PASP ≥ 50 mmHg at peak stress was considered as indicative of abnormal increase in PASP. Diastolic times and the diastolic/systolic time ratio were recorded by a precordial cutaneous force sensor based on a linear accelerometer.At baseline, PASP was 30 ± 5 mmHg in patients and 25 ± 4 in controls. At peak stress the PASP was normal in 95 patients (Group 1); 14 patients (Group 2) showed an abnormal increase in PASP . At 100 bpm, an abnormal (< 1) diastolic/systolic time ratio was found in 0/16 (0%) controls, in 12/93 (13%) Group 1 and 7/14 (50%) Group 2 patients (p < 0.05 between groups).The first and second heart sound vibrations non-invasively monitored by a force sensor are useful for continuously assessing diastolic time during exercise. Exercise-induced abnormal PASP was associated with reduced diastolic time at heart rates beyond 100 beats per minute. Pulmonary hypertension is frequent in patients with heart failure, contributes to exercise intolerance and is associated with a worse outcome . The degWe enrolled 109 consecutive patients referred for exercise stress echocardiography  and 16 volunteers as controls. The characteristics of the study patients are reported in Table All patients met the following inclusion criteria: 1) referred to stress echo for clinically driven testing; 2) sinus rhythm; 3) negative stress echocardiography. Of the initially considered 144 patients, 35 were excluded for one of the following reasons: 1) severe valvular disease or congenital heart disease (n = 11); 2) unwillingness to enter the study (n = 2); 3) poor acoustic window (n = 4) or unfeasibility of the spectral profile of tricuspid regurgitation (n = 14); positive stress echo (n = 4). The study complies with the Declaration of Helsinki. Informed consent was obtained from all patients (or their guardians) before testing, and the study protocol was approved by the institutional ethics committee. Stress echo data were collected and analyzed by stress echo cardiographers not involved in patient care. Indications for stress echocardiography were suspected coronary artery disease in 40 (37%) and risk assessment of known coronary artery disease in 48 (44%) cases, prognostic stratification in idiopathic (4 cases) or ischemic dilated (5 cases) cardiomyopathy, valvular heart disease in 17 ; 18 patients with suspected coronary artery disease had established chronic obstructive pulmonary disease with effort dyspnea. Known coronary artery disease was history of myocardial infarction or coronary revascularization and/or presence of ≥ 1 angiographically documented coronary stenosis > 50%. Stress echocardiography was performed on medical therapy in 79 (72%) patients , mild, moderate, or severe .The pulmonary artery systolic pressure was derived from the maximal velocity of tricuspid Doppler tracing according to the Bernoulli equation, and adding the value of the right atrial pressure . Right aLeft ventricular end-diastolic volume and end-systolic volume were obtained from apical four-chamber and two-chamber view using the biplane Simpson method . The endIn order to build the end-systolic pressure-volume relation, the force was determined at rest and at peak of stress as the ratio of the end-systolic pressure/end-systolic volume index (biplane Simpson rule/body surface area). The end-systolic pressure-volume relation was built offline .In all, ventricular arterial coupling was indexed by the ratio of left ventricular systolic elastance index (systolic pressure/end-systolic volume index) to arterial elastance (ratio of end-systolic pressure by stroke volume). Echocardiography (for end-systolic volume and stroke volume) and cuff sphygmomanometer  provided the raw measurements. Because stroke volume (and input impedance) varies directly with body size, arterial elastance was adjusted for body surface area to better reflect differences in arterial properties with age and between the genders adjusted for differences in body size ,16.The stroke volume was calculated as: stroke volume (mL) = end-diastolic volume - end-systolic volume. Stroke volume was indexed by dividing it by body surface area.2) standardizes cardiac output for body size.The Cardiac Output (L/min) was calculated as: heart rate*stroke volume. Cardiac output was indexed by dividing it by body surface area. Cardiac Index (L/min/m2) with a resolution of 0.0005·g. We housed the device in a small case which was positioned in the mid-sternal precordial region and was fastened by a solid gel ECG electrode. The acceleration signal is acquired along with an ECG signal and transmitted to a laptop PC by wireless connection. The data are analyzed using software developed in Matlab . A peak detector algorithm synchronized with the ECG scans the first 150 ms following the R-wave to record first heart sound force vibrations and the 100 ms following the T-wave to record second heart sound force vibrations. These values are then filtered by a median filter, which averages the beat-to-beat variations in the signal and removes outliers caused by movement artefacts. Contractility quantification through the first heart sound amplitude recording has been previously demonstrated [All the enrolled subjects, scheduled for exercise stress, had standard ECG, pressure and complete (both stress and recovery) sensor evaluation. The transcutaneous force sensor is based on a linear accelerometer of the LIS3 family . The device includes in a single package a micro electro-mechanical system sensor that measures capacitance variation in response to movement or inclination and a factory trimmed interface chip that converts the capacitance variations into analog signals proportional to the motion. The device has a full scale of ± 2·g . Pearson chi-square with Fisher's exact test for categorical variables and the Mann-Whitney test for continuous variables for inter-group comparisons were performed to confirm significance . One-way analysis of variance was used to compare continuous variables between groups; when homogeneity of variance was not present, the Kruskal-Wallis test for nonparametric independent samples was used. Intergroup comparison was performed with Scheffe and Tamhane post hoc tests, respectively. Relations between variables were assessed using linear regression analysis and Pearson's correlation coefficient. Analysis of variance with Fisher's post hoc pairwise multiple comparisons was used to assess the significance of intragroup repeated measures.By selection, technically adequate images were obtained in all patients at baseline and during stress, and no test was interrupted because of limiting side effects. Resting left ventricular ejection fraction in the entire study population was 57 ± 12%.By selection, the 109 patients performed the exercise test without chest pain, ST-segment depression, or echocardiographic evidence of inducible ischemia. The hemodynamic and Doppler echocardiographic variables obtained during exercise are shown in Table A consistent first heart sound and second heart sound signal was obtained in 107 out of 109 patients at rest and during stress. In 2 patients data were discarded because of a low signal-to-noise ratio which was related to both small amplitude of the signal and the presence of several artifacts. From rest to peak exercise, the mean systolic time was shortened by 23 ± 11%. The diastolic time decreased more markedly during exercise (by 50 ± 14% at peak stress). At 100 bpm heart rate during exercise, 19 patients showed a reversal of the diastolic/systolic ratio, with the duration of systole longer than that of diastole. The patients with abnormal exercise-induced increase in pulmonary artery pressure showed both at low (80 bpm) intermediate (100 bpm) and 110 bpm during stress prolonged systolic times, reduced diastolic times, and reduced diastolic/systolic time ratios. At intermediate (100 bpm) heart rates an abnormal (< 1) diastolic/systolic time ratio was found in 0/16 (0%) controls, in 7/14 (50%) patients with and 12/93 (13%) patients without abnormal exercise-induced increase in PASP, p < 0.05 between groups .Peak stress heart rate was higher in controls vs patients with and without abnormal exercise induced increase in PASP Table . Upper hIncreased systolic pulmonary artery pressure during exercise has been hypothesized to signify occult left ventricular dysfunction. In a previous study in a selected population of patients with chronic severe mitral regurgitation and apparently normal left ventricular function, Agricola  showed tIn our study we found that abnormal exercise-induced PASP was associated with blunted left ventricular contractile reserve as assessed by the systolic pressure/end-systolic volume index relation. Furthermore, for the first time, we found an association with reduced diastolic time and with diastolic/systolic time mismatch at heart rates beyond 80 beats per minute.During exercise, an increase in pulmonary artery pressure may theoretically result from a reduction in time available for the diastolic mitral inflow in the face of a fully distended circuit  and a riFirst heart sound vibrations are an expression of the tension wave produced during initial activation of the heart in the isovolumic contraction phase and are fairly consistent in sinus rhythm. Second heart sound vibrations generates from the abrupt deceleration of the moving aortic blood mass at the beginning of the isovolumic relaxation phase . We demoFeasibility in humans and reproducibility of the first cardiac tone, of the second cardiac tone amplitude monitoring, and of diastolic time assessment at increasing heart rates induced by exercise or pharmacological stressors has been previously validated ,8,22. InSeveral limitations should be acknowledged. We did not perform invasive measurement of either PASP at rest or during exercise, excluding assessment of pulmonary vascular resistance as an indicator of input impedance . We usedStress-induced "diastolic-systolic mismatch" can be easily quantified by a disproportionate decrease of diastolic time fraction, and is associated to several cardiac diseases, possibly expanding the spectrum of information obtainable during stress echo. Doppler echocardiography is the standard method for non-invasive diastolic function assessment However there are technical difficulties in assessing Doppler variables that influence cardiac diastolic filling during exercise. Interpretable E/E' are not always obtained, since the most common source of uninterpretable tracings is fusion of E and A velocities due to tachycardia . A bettePortability of the sensor and simple remote transmission of the signal could allow telemonitoring in chronic heart failure patients. Dichotomy patterns: upsloping vs flat systolic Force-Frequency Relation , stress-The sensor-monitored first and second heart sound vibrations were utilized as time markers to continuously assess diastolic time during exercise, in a non-invasive, imaging-independent, objective assessment. Abnormal exercise-induced PASP was associated with reduced diastolic time and with diastolic/systolic time mismatch at heart rates above 80 beats per minute. A blunted diastolic time fraction worsens ventricular filling and coronary perfusion time.The sensor for the diastolic time measurement is an embodiment of the United States Patent 6,859,662. Inventor: T.B.All authors read and approved the final manuscript. TB conceived and designed the research, performed statistical analysis and drafted the manuscript; EB analyzed the data; RS and EP did critical revision of the manuscript for important intellectual content.


To overcome flow and electrocardiogram-trigger artifacts in cardiovascular magnetic resonance (CMR), we have implemented a cardiac and respiratory self-gated cine ultra-short echo time (UTE) sequence. We have assessed its performance in healthy mice by comparing the results with those obtained with a self-gated cine fast low angle shot (FLASH) sequence and with echocardiography.t test and Bland-Altman analyses.2D self-gated cine UTE  and self-gated cine FLASH  images were acquired at 9.4 T. Volume of the left and right ventricular  myocardium as well as the end-diastolic and -systolic volume was segmented manually in MR images and myocardial mass, stroke volume (SV), ejection fraction (EF) and cardiac output (CO) were determined. Statistical differences were analyzed by using Student blood-myocardium = 25.5 ± 7.8). Compared to cine FLASH, susceptibility, motion, and flow artifacts were considerably reduced due to the short TE of 314 μs. The aortic valve was clearly discernible over the entire cardiac cycle. Myocardial mass, SV, EF and CO determined by self-gated UTE were identical to the values measured with self-gated FLASH and showed good agreement to the results obtained by echocardiography.Self-gated cine UTE provided high quality images with high contrast-to-noise ratio (CNR) also for the RV myocardium (CNRSelf-gated UTE allows for robust measurement of cardiac parameters of diagnostic interest. Image quality is superior to self-gated FLASH, rendering the method a powerful alternative for the assessment of cardiac function at high magnetic fields. Cardiovascular magnetic resonance (CMR) is increasingly often performed at very high magnetic field strength, up to 7 T for human subjects and up to 17.6 T for small animal models -10. A ve2[One option to overcome these problems is to perform CMR with methods which allow for minimized TE . Data ac2,14, UTE 2, MR angi2 or detec2,17. AlthA self-gated version of radial data acquisition has previously been proposed and shown to be able to compete in terms of SNR and contrast-to-noise ratio (CNR) with both ECG-triggered acquisition  and cartExperiments were performed on six 12 weeks old (22 ± 1 g) healthy female C57BL/6 wild-type mice, purchased from Harlan-Winkelmann . All animal studies were performed with the approval of the State Review Board of North Rhine-Westphalia, Germany (Az. 87–51.04.2011.A003). Mice were imaged using self-gated cine FLASH  and self-gated cine UTE sequences to assess the two imaging sequences with respect to CNR and cardiac functional parameters. As comparison, mice were also measured by ultrasound.2) mice were shaved precordially using a commercially available electro-shaver and secured in a supine position on the heating pad of the VEVO 2100 with a feedback rectal body heat control holding a temperature of 38°C and controlling one-lead electrocardiogram heart rate above 400 bpm constantly for the normal scanning time of 20 minutes. Warmed and centrifuged gel was applied to the chest of the examined mice and examinations were performed with the system’s 25 MHz linear probe. ECG-triggered parasternal short axis views of the whole mouse heart were obtained in steps of 100 μm together with a parasternal long axis view. Routinely pulsed wave Doppler signals of the velocity time integral of the mitral valve inflow, the aortic outflow and the pulmonic outflow were obtained.Cardiac Doppler-Echocardiography was performed on a specialized ultrasound biomicroscope for examination of murine models with high temporal (up to 1000 pictures per second) and spatial resolution (down to 35 μm) . Examinations were performed as previously described ,21. In bUltrasound image analysis was performed independently by two experienced ultrasound readers using the VEVO 2100 implemented image analysis. 2D images were manually segmented for end-diastolic and end-systolic heart cycle. Velocity time integrals of the valvular blood flow signals were manually segmented, too. Calculations of the volumes followed Teichholz’s formula (m-mode) and Simpson’s formula (2D). Calculations of cardiac output (CO), stroke volume (SV) were based on either the 2D measurements or the continuous flow formula.2; averages, 1; TE, 0.314 ms; TR, 6.2 ms; flip angle, 15°; pulse shape, gaussian; pulse length, 0.3 ms; number of projections, 246; polar undersampling, 2.0; number of movie cycles, 200; acquisition bandwidth, 100 kHz; scan time per slice, 5 min 5 sec. No half-pulse was used. Gradients were ramped in a 160-μs delay, which allowed for gradient rising to full amplitude  and preemphasis corrections. K-space was sampled with constant increments of the backprojection angle. After the acquisition a delay of 2.5 ms was applied to achieve the same TR as in the FLASH sequence. For reconstruction, interpolation of the radially sampled k-space data onto a Cartesian grid was performed by a Kaiser Bessel Kernel regridding algorithm [2; averages, 1; TE, 3 ms; flip angle, 15°; pulse shape, gaussian; pulse length, 0.5 ms; TR, 6.2 ms; number of repetitions, 200; acquisition bandwidth, 75 kHz; scan time per slice, 4 min 49 sec.CMR images of healthy C57BL/6 mice were acquired at 9.4 T on a Bruker BioSpec 94/20  equipped with a 1 T/m gradient system and a 35 mm volume coil. The MR system was interfaced to a console running ParaVision software 5.1 including the IntraGate software for sequence acquisition and reconstruction. For MR acquisition a cardiac and respiratory self-gated UTE sequence was implemented and animals were imaged with the following parameters: slice thickness, 1 mm; number of slices, 9; matrix size, 156 × 156; field of view, 20 × 20 mmlgorithm -24. A stDuring CMR measurements, animals were anesthetized with 2% isoflurane and were monitored for core body temperature and respiration rate using a CMR compatible monitoring system .For retrospective sorting of the acquired image data, self-gated CMR sequences rely on additional data that are recorded at some point during the repetition time. In the IntraGate FLASH sequence these data are recorded either during refocusing of the slice signal or by an additional navigator slice. If the navigator signal is derived from the slice signal, the phase encoding and pre-read dephase gradients need to be separated from the slice rephase gradient, which leads to a prolonged TE Figure A. The exIn self-gated cine UTE sequences, however, the navigator signal is derived directly from the MR signal of the image acquisition. During center-out radial k-space sampling each spoke contains the central k-space in its origin, which leads to a further shortening of TE Figure C.Since the navigator signals have a constant encoding, they record all disturbances that occur during the measurement. Presuming that respiratory motion, cardiac motion and/or pulsatile blood flow occurs within the slice that is used to derive the navigator, a respiration and cardiac signal can be deduced and used for the retrospective reconstruction of a cardiac cine.CNR as measure for image quality was calculated between the left and right myocardial wall and the ventricles for the end-diastolic and end-systolic frame as CNR = /standard deviation_noise. Signal intensities and standard deviations were determined using the Amira software  as mean value over all segmented slices.In UTE images CNR was also determined between the right myocardial wall and the adjacent tissues of lung, liver and muscle. Volumetric analysis of the left and right myocardium, and ventricles was performed using the Amira software. The regions of interest in the MR images were selected manually on the end-diastole and end-systole frame of each slice by tracing the epicardial and endocardial borders. In order to obtain the global parameters of the entire heart the volume for each frame was calculated as the sum of the area of interest in each slice multiplied by the slice thickness. SV, CO per minute and the ejection faction (EF) were calculated from the blood volume, determined in the end-systolic and end-diastolic phase.3.Left ventricular (LV) and RV mass was calculated by multiplying the volume of the LV and RV myocardium by the tissue density of 1.05 g/cmt test. All aspects of analysis were performed by two CMR specialists independently.In addition to the determination of the functional cardiac parameters, the self-gated cine FLASH and UTE sequence was assessed with respect to flow artifacts (Q1), their boundary between the ventricular blood and the myocardium including the papillary muscles (Q2), susceptibility artifacts at the myocardium-lung interface (Q3), their interference with the depiction of the RV myocardium (Q4), acquisition artifacts (Q5) and the overall suitability for segmentation of the LV cavity and the myocardium using Segment  and Amira software (Q6). The rating was performed in a blinded fashion using a 5-level scale from one to five . Statistical differences between both the functional and the quantitative values obtained for the two sequences were analyzed using Student 2 in-plane; 1 mm slice) in the same acquisition time of 5 min per slice. Both sequences yielded high quality images, with CNR values above 20  sequence that is routinely used in CMR on mouse models. Both sequences acquired the same number of frames over the cardiac cycle with the same spatial resolution (129 μm)29 μm2 in2*-weighted acquisitions in all cardiac phases, in particular at tissue interfaces which affected mostly the right myocardium in proximity to the lung . The importance of minimized TE is illustrated in Figure Figure 2*-weighted FLASH or the UTE sequence. LV and RV myocardium as well as cavity were manually segmented and myocardial mass, SV, EF and CO were calculated. The LV morphological and functional parameters measured with self-gated UTE perfectly reproduced the values measured with the self-gated gradient echo method. For the RV parameters slightly but not significantly increased values were observed for myocardial mass (p = 0.10) and EF (p = 0.34) (Table LV and RV heart function was assessed on the basis of the cardiac images acquired with either the TEF p = 0.4 (Table 2 and T2* weighted images hampered the visualization of the aortic valves in open position (Figure As shown in Figure n Figure C, UTE imn Figure B.We have implemented and used a self-gated UTE sequence for assessment of functional cardiac parameters in mice at a magnetic field strength of 9.4 T. The center-out acquisition scheme allowed for a TE of only 314 μs, which minimized typical high field problems like flow and susceptibility artifacts. A further reduction in TE can be achieved when a half-pulse excitation is used ,27. HoweAs expected, the minimized TE almost completely suppressed flow and susceptibility artifacts Figure  and thusFor assessment of cardiac functional indices it has previously been found that self-gating sequences yield comparable values to those obtained with prospective triggering . Our datA recent study has found that self-gated sequences are more robust and more efficient for imaging of the aorta in mice . HoweverIn conclusion, we have shown that self-gated UTE is a reliable and accurate technique in CMR and allows for robust and versatile measurement of most cardiac parameters of diagnostic interest. The sequence provided high quality images and compared to self-gated FLASH, susceptibility and flow artifacts were significantly decreased in particular during the inflow phase of the cardiac cycle due to the use of short TE. Enhanced image quality allowed for reliable quantification of both the left and right ventricular function and made the visualization of small anatomical structures such as the papillary muscles and the cardiac valve possible during one cardiac cycle.The authors VH, NN, MK, JS and CF declare that they have no competing interests. AN is an employee of Bruker BioSpin MRI GmbH.VH coordinated the study, designed experiments, performed CMR, collected and analyzed data and wrote the manuscript, NN designed experiments, performed CMR and analyzed data, AN wrote and implemented the self-gated UTE pulse sequence program, MK designed experiments, JS performed echocardiography and analyzed data, CF designed experiments and wrote the manuscript. All authors edited the manuscript. All authors read and approved the final manuscript.


Objective. Anorexia nervosa is a condition of reduced hemodynamic load, characterized by varying degrees of cardiac remodelling, only in part related to reduced body mass; the mechanism for such variability, as well as its clinical significance, remains unknown. Aim of the study was to assess the possible influence of a great number of clinical, biochemical, and endocrine factors on cardiovascular parameters in restrictive anorexia nervosa. Method. Twenty-five female patients hospitalized for restrictive anorexia nervosa underwent extensive cardiovascular, clinical, and biochemical evaluation. Results. Height-adjusted and cardiac workload-matched left ventricular mass was significantly related to several endocrine parameters, blood pressure, and vasoreactivity. On multivariate analysis, IGF/GH ratio and systolic blood pressure were the only independent predictors of height-adjusted ventricular mass ; when matching for cardiac workload, left ventricular mass was independently predicted only by GH and FT3 levels. All effects were independent of patient's weight and BMI. Conclusions. Indices of endocrine impairment seem to be the most relevant determinants of left ventricular hypotrophy in anorectic patients, apparently independent of reduced hemodynamic load and BMI. In particular, IGF/GH ratio and FT3 seem to particularly affect left ventricular mass in this population. Anorexia nervosa (AN) is a common psychiatric disorder, characterized by weight loss, protein-energy malnutrition, and severe organic complications leading to increased long-term morbidity and mortality; despite the prevalence and severity of this condition, clinicians still rely mainly on BMI and clinical assessment in the risk stratification of AN patients . Most ofTo date, no study has tried to specifically identify the determinants of such variability in left ventricular mass and cardiovascular pattern of AN patients.Twenty-five women with restrictive-type AN were enrolled during hospitalization at the local psychiatric institution. Diagnosis of AN was confirmed by two independent consultant psychiatrists following current DSM-IV criteria . BingingMost patients underwent both cardiovascular assessment and blood sampling before the beginning of any therapeutic intervention; in the minority of patients enrolled during urgent hospitalization, blood sampling occurred before treatment, while cardiovascular assessment was delayed to two to three days after start of refeeding. The study conformed to the Declaration of Helsinki. Patients and their families gave informed consent to the procedures.Patient's weight and body composition were studied by means of a footpad bioelectrical impedance analyzer  by using manufacturer-provided formulas. Blood pressure was measured after ten minutes of rest in a sitting position, using a standard adult or pediatric arm-cuff, according to the subject's arm circumference.A complete echocardiographic examination was performed using a commercially available system . Left ventricular mass (LVM) was estimated using M-Mode measurements of left ventricular wall thickness and diameters, following the recommendations of the American Society of Echocardiography ; the estIn order to take into account the reduced hemodynamic load of this particular population, weight-independent, height- and stroke-work-predicted left ventricular mass was calculated for each subject by means of a validated formula, as previously described by others in a similar population ; LVM% waEndothelial-dependent dilation was assessed with the flow-mediated dilation test (FMD) of the brachial artery with Doppler echocardiography, according to the recommendations of the International Brachial Artery Reactivity Task Force . The uppCardiac evaluation also included 24-hour ambulatory ECG monitoring, with subsequent offline analysis of heart rate variability (HRV) both in frequency and time domain, as described elsewhere .For each instrumental technique, the same investigator performed and analyzed all assessments.3, FT4, prolactin, and DHEAS. Serum GH was assayed with an immunoradiometric assay IRMA method and serum IGF-I with an RIA using a monoclonal antibody after acid-ethanol extraction. Evaluation of plasma TSH levels was performed by an ultrasensitive immunoradiometric assay with a detection limit of 0.05 mU/L. Serums FT4 and FT3 were measured using the Lisophase Kits (Bouty). All samples were also analyzed for common biochemistry, electrolytes, and complete blood count.Venus blood samples were collected in the morning, after an overnight fast (14 hrs), for measurement of insulin-like growth factor 1 (IGF-1), growth hormone (GH), cortisol, ACTH, thyrotropin (TSH), FTt-test was used for difference between subgroups. The Pearson (r) correlation method was used for correlation analysis between continuous variables. A P < 0.05 was considered significant. Linear regression analysis was performed to identify cofactors predictive of lower LVMh and LVM%; significantly associated dependent variables were then analyzed in a stepwise multiple regression model.Data are expressed as means ± SDs. Analysis was performed using SPSS version 12 . Log-transformed values were used for statistical analysis of the ratio of IGF-1 to GH (log IGF1/GH), as already described by others . Two-sidPatient characteristics, echocardiographic, electrocardiographic, vasoreactivity, biochemical, and endocrine parameters are shown in Subgroup analysis comparing patients with “inadequately” low LVM% see  only shor = 0.638, r = 0.706, and r = 0.618; P = 0.001 for LVMh; r = 0.603; r = 0.489; r = −0,54; P < 0.05 for all). Correlation analysis revealed strong, significant correlations between logIGF-1/GH and both LVMi, LVMh, and LVM%  were significantly correlated with the patient's BMI, while no significance was found for GH, logIGF1/GH, DHEAS, and thyroid hormones.Among hormonal parameters, only IGF-1 . These were used for multiple, backward, stepwise linear regression; in such analysis logIGF-1/GH, and SBP revealed as the only independent predictors of LVMh and LVMi . Linear regression analysis was performed looking for predictors of LVMh among all explored variables. Covariates found significant at univariate analysis were SBP, FMD, GH, logIGF-1/GH . A further analysis was performed using LVM% as the dependent variable; significant univariate cofactors were BMI, GH levels, logIGF-1/GH and FTNo significant correlation was found between HRV parameters, body composition and any of the hormones measured.This is the first study to systematically address the determinants of cardiac alterations in AN. The patterns of cardiac and endocrine alterations in our patients substantially resemble those reported in previous studies. Although IGF-1 and cortisol correlated well with body weight and BMI, not all of the variability in IGF1 : GH ratio and thyroid hormone levels seems attributable to body composition alone; this phenomenon has recently been described in a larger report, and it might account for some of the clinical and prognostic discrepancy among patients with similar BMIs : individ3, and reduced LVM in anorectic patients. Interestingly, this association seems to act independent of body weight, BMI, left ventricular afterload and peripheral markers of malnutrition. It is therefore likely that the very low values of LVM observed in some emaciated patients do not exclusively reflect reduced hemodynamic requirements due to low body mass, as elsewhere postulated, but also mirror a more complex alteration of the metabolic and endocrine status of the whole organism. The present results suggest a strong association between high GH levels, low IGF-1, low FT3 and IGF-1 exert potent physiologic trophic effects on the myocardium, both in health and disease; it is therefore reasonable that only those patients who develop a multiple endocrine dysfunction with peripheral resistance to GH and low FT3 levels besides weight loss also show inadequately low cardiac mass. Although it is common sense to conceive the endocrine changes of anorexia as adaptive responses to starvation, such changes have recently been demonstrated to predict high short-term probability of severe organic complications, in a fashion independent of BMI and other “traditional” markers [Actually, only a subgroup of patients in our cohort showed “inadequately” low LVM (about 30% of the subjects); this is in line with the most important studies in the field to date, and our findings propose an intriguing explanation of this heterogeneity , 8. Thes markers ; our stu markers .Our findings also put forward again the question whether the alterations in the somatotropic axis are among the main actors of the “metabolic blockade” typical of the most compromised AN patients, in whom muscle catabolism can continue despite aggressive nutritional support. Many groups have hypothesized a beneficial effect of GH and IGF-1 administration on appetite, muscle metabolism, and bone mass density in AN . The stu3 levels and cardiac hypotrophy; similarly, no prognostic effect can be asserted from our data alone. Larger, longitudinal follow-up studies in similar populations will be of help in this regard.The present study is mainly limited by the small number of subjects examined; however, both cardiac and endocrine findings in our patients were reasonably compatible with those of previous works. The absence of a control group was intentional, as all of the explored parameters had already been individually studied in similar populations. Growth hormone status is best assessed by means of multiple measurements throughout the day and overnight; this was not performed due to logistical reasons in this particular population. Of course, no causative relationship can be asserted between GH/IGF1 imbalance, FT3 levels seem to be the best predictors of low left ventricular mass beyond hemodynamic load and BMI. Therefore, cardiac phenotype seems a valuable candidate parameter for prognostic stratification in this patient population.Our results confirm that left ventricular remodelling is very variable in AN and show that parameters of GH-resistance and low FT


To evaluate the association of left ventricular (LV) diastolic function and N-terminal pro-brain natriuretic peptide (NT-proBNP) with renal function in essential hypertension.99mTc-DTPA. GFR from 30 to 59 ml/min/1.73 m2 was defined as Stage 3 chronic kidney disease (CKD). GFR was also estimated using the modified MDRD equation. Albuminuria was defined by urinary albumin/creatinine ratio (UACR).LV diastolic function was estimated by the ratio of early diastolic velocities (E) from transmitral inflow to early diastolic velocities (E′) of tissue Doppler at mitral annulus ; NT-proBNP was measured in 207 hypertensive patients (mean age 56±14 years). The subjects were classified into 3 groups: E/E′≤10 group (n = 48), 10<E/E′≤15 group (n = 109) and E/E′>15 group (n = 50). The renal function was estimated by glomerular filtration rate (GFR) with p<0.0001), GFR was significantly negative and UACR was positive correlated with E/E′ and NT-proBNP (p<0.0001). In multivariate stepwise linear analysis, GFR had significant correlation with age (p = 0.001), gender (p = 0.003), E/E′ (p = 0.03), lgNT-proBNP (p = 0.001) and lgUACR (p = 0.01), while eGFR had no significant correlation with E/E′ or lgNT-proBNP. Multivariate logistic regression analysis, adjusted for potential confounding factors, showed that participants in E/E′>15 group were more likely to have Stage 3 CKD compared with those in E/E′≤10 group with an adjusted odds ratio of 8.31 (p = 0.0036).GFR was lower and UACR was higher in E/E′ >15 group than in 10< E/E′ ≤15 group or E/E′ ≤10 group (LV diastolic function, assessed with E/E′ and NT-proBNP is associated with renal function in essential hypertension. Chronic renal dysfunction has a negative effect on cardiac function Tissue Doppler imaging (TDI) is a new method for assessing left ventricular systolic and diastolic function in cardiac diseases. Diagnostic evidence of LV diastolic dysfunction can be obtained non-invasively by TDI (E/E′>15) according to the European Society of Cardiology 99mTc) diethylenetriaminepentaacetic acid (DTPA) in essential hypertension.Despite extensive knowledge about cardiac structure and function in patients with ESRD Two hundred and eighty patients were screened for this study, among them, 49 patients due to secondary hypertension, 10 patients due to suboptimal images and 14 patients due to absent biomarker results were excluded. A total of 207 essential hypertensive patients  were enrolled into the study consecutively from the hypertension department or clinic in Ruijin hospital from January 2009 to January 2011. Prior informed consent was obtained from all patients for participation in the study. All the participants provide their written informed consent to participate in this study. This study was approved by the Ethics Committee of Ruijin Hospital.2 were excluded from the study. Systolic left ventricular dysfunction is defined as ejection fraction less than 50%.The inclusion criterion was a diagnosis of essential hypertension according to 2005 Chinese guidelines for the prevention and treatment of patients with hypertension et al2 body surface area. Left atrial volume was indexed by body surface area as LA volume index (LAVI) in g/m2 body surface area.Comprehensive transthoracic echocardiography was performed using a cardiac ultrasound system . LV diameters, septal and posterior wall thickness were measured according to the guidelines of the American Society of Echocardiography The peak early (E) and late (A) transmitral flow velocities, the ratio of early to late peak velocities (E/A), deceleration time of E velocity and isovolumic relaxation time (IVRT) were measured. The mitral flow velocity was obtained from apical 4-chamber view by placing a pulsed-wave (PW) Doppler sample volume between mitral leaflet tips during diastole. The curve of continues wave Doppler was put between the LV out flow and inflow tract and recording a trace of LV out flow tract and inflow waves from the apical 5-chamber view. The IVRT measurement was estimated from the cessation of the aortic flow and the onset of transmitral inflow.Tissue Doppler imaging (TDI) was performed by means of mitral annulus in four-chamber view. The early peak diastolic annular (E′) was determined from the TDI recordings. The ratio of peak early (E) to tissue Doppler early diastolic (E′) was calculated.According to the statement of the European Society of Cardiology To calculate the intra-observer variability, the parameters were reassessed in the first 20 patients by the same observer without reviewing the patients’ previous reports, 4 weeks after the first set of the evaluation.Plasma NT-proBNP levels were determined using the electrochemiluminescence immunoassay “ECLIA” on Elecsys and cobas e immunoassay analyzers .99mTc-DTPA, an agent commonly used for renal scintigraphy. GFR from 30 to 59 ml/min/1.73 m2 was defined as Stage 3 CKD. GFR was also estimated using the modified MDRD equation for Chinese patients with chronic kidney disease Renal function was measured by GFR following injection of UACR was measured to identify subclinical renal damage. Urine albumin was measured quantitatively with an immunoephelometry test  and creatinine was assessed quantitatively with an enzymatic colorimetric test . UACR was calculated using the following formula: [urine albumin(mg/l)/urine creatinine(g/l)].p value of 0.05 or less: LVMI, LAVI, E/A, deceleration time, IVRT, E/E′, lgNT-proBNP and lgUACR. In the multivariable logistic regression, models, we adjusted for the potential confounding factors including age, sex, body mass index, prevalence of diabetes, the use of ACE-I or ARB drugs, 24 h mean systolic blood pressure, LVMI, LAVI, E/A, deceleration time, IVRT, lgNT-proBNP and lgUACR to evaluate the association of E/E′ with Stage 3 CKD. A p value of <0.05 was defined as statistically significant, and a p value of <0.01 as highly significant.Data were stored and analyzed using the SPSS 13.0 statistical package . All results are presented as mean values ± SD. Because NT-proBNP and UACR levels were not normally distributed, lgNT-proBNP and lgUACR were used in correlations and regression models. The difference of the intercept of the linear regression line between 2 groups was analyzed using analysis of covariance. Differences between studied groups were compared by one-way ANOVA, and differences with respect to categorized data by χ2 test. Multivariable adjusted test for trend was employed to assess the association between lgUACR and E/E′ or lgNT-proBNP categories after adjusting for baseline clinical characteristics. Linear regression was performed for the univariate model of GFR, eGFR and serum creatinine. Multivariable linear regression models for the relationship between continuous variables and GFR or eGFR category adjusted for age, gender, the use of ACE-I or ARB drugs, blood pressure, heart rate, and covariates that differed significantly by GFR or eGFR category with The subjects were classified into 3 groups based on left ventricular diastolic function: group 1 with normal LV diastolic function of E/E′≤10 ; group 2 with suspected LV diastolic dysfunction of 10<E/E′≤15 ; group 3 with LV diastolic dysfunction of E/E′>15 . The variation coefficient of LVMI, LAVI, E/A, deceleration time, IVRT and E/E′ was 7.2%, 6.1%, 8.4%, 8.3%, 6.2% and 6.3% respectively.p<0.0001), LVMI (p<0.0001), IVRT (p = 0.0003), lgNT-proBNP (p<0.0001) and lgUACR (p<0.0001) were significantly higher, while GFR (p<0.0001) and eGFR (p = 0.0002) were significantly lower (p = 0.0002) than in group 1 or 2. Patients in group 2 were older and had higher BMI, LVMI, lgNT-proBNP than those in group 1. There was no difference in the using of antihypertensive medicine in the 3 groups.Anthropometric, metabolic, hemodynamic, and echocardiographic characteristics, as well as the medical history of the study patients are included in p<0.0001), gender(p = 0.002), 24-h mean systolic blood pressure(p = 0.043), 24-h mean heart rate(p = 0.001), LVMI(p<0.0001), LAVI(p<0.0001), E/A(p = 0.003), deceleration time(p = 0.006), IVRT(p<0.0001), E/E′ (p<0.0001), lgNT-proBNP(p<0.0001) and lgUACR(p<0.0001). Of the 42 diabetes patients in our study, 19 patients were new-developed diabetes and 23 patients were with diabetes history. In all the 42 diabetes patients, GFR had no relationship with diabetes .As shown in p = 0.001), gender (p = 0.003), E/E′ (p = 0.03), lgNT-proBNP (p = 0.001) and lgUACR (p = 0.01) in multivariate stepwise linear analysis . Logarithmically transformed UACR was significantly correlated with E/E′ and lgNT-proBNP . After adjustment for age, gender, diabetes prevalence, use of ACE-I or ARB drugs, GFR, 24-h mean systolic and diastolic blood pressure, 24-h mean heart rate, lgUACR was also significantly correlated with E/E′  and lgNT-proBNP . E/E′ was significantly correlated with lgNT-proBNP, the correlation coefficient was 0.544 (p<0.001).p<0.0001), gender(p = 0.007), 24-h mean heart rate(p = 0.001), LVMI(p<0.0001), LAVI(p<0.0001), deceleration time(p = 0.003), IVRT(p<0.0001), E/E′ (p<0.0001), lgNT-proBNP(p<0.0001) and lgUACR(p<0.0001) in Pearson’s correlation analysis (p<0.0001), gender (p = 0.02), lgUACR (p = 0.005) and IVRT (p = 0.02), but had no significant correlation with E/E′ or lgNT-proBNP , while there was no difference in GFR between E/E′<15 group and E/E′>15 group in patients with lgNT-proBNP<1.65 .The median of lgNT-proBNP was 1.65, so we divided the patients into 2 groups as shown in p = 0.0003). The test for the trend was significant (p for trend <0.0001). After adjusting for age, gender, and body mass index, participants in group 3 were still more likely to have Stage 3 CKD compared with those in group 1 . Further adjustments for other potential confounding factors including age, gender, body mass index, prevalence of diabetes, the use of angiotensin-converting enzyme inhibitor or angiotensin receptor blocker drugs, 24-h mean systolic blood pressure, LVMI, LAVI, E/A, deceleration time, IVRT, lgNT-proBNP and lgUACR did not materially change the magnitudes of the associations . The tests for the trend in the multivariable analyses were all significant (p for trend = 0.0006 and 0.002)  compared with those in group 1 (odds ratio (OR): 6.46, 95% confidence intervals (95% CI) 2.33–19.91; d 0.002) .No significant relationships between E/E′ and 30<eGFR<59 were observed  .99mTc-DTPA clearance to measure GFR, precise and reliable relationships were found between cardiac and renal status, even in patients displaying only mild to modest declines in GFR.The current study investigated the relationship between LV diastolic function and renal function in early essential hypertension. We found that parameters of LV diastolic function including E/E′ and NT-proBNP levels were associated with renal impairment, manifested as both albuminuria and mild reductions in GFR. Using the reference technique of In the present study, we used TDI to assess diastolic function of the left ventricle. By using the combination of TDI of mitral annulus and mitral inflow velocity from conventional Doppler (E/E′), which is relatively independent of loading conditions, was superior to conventional blood flow Doppler echocardiography indices (E/A) of LV relaxation  25. However, IVRT by itself has limited accuracy, reductions in preload (and increases in afterload) exhibit a transmitral pattern similar to impaired relaxation  IVRT is also used for the direct estimation of LV relaxation99mTc-DTPA) enable accurate (low bias and high precision), and reproducible measurements of GFR, since the plasma clearance of 99mTc-DTPA has been shown to correlate well with the renal clearance of inulin (r>0.90) 99mTc-DTPA measured GFR and estimated GFR using the modified MDRD equation for Chinese patients among patients of E/E′>15, 10<E/E′≤15 or E/E′≤10. However, eGFR had no correlation with E/E′ or lgNT-proBNP in multivariate analysis. By using the radiolabeled tracers (99mTc-DTPA) to estimating GFR, our results showed that LV diastolic function was associated with renal function in essential hypertensive patients.Although eGFR has been widely used in the studies investigating the relationship between LV function and renal function, the association between small reductions in eGFR and abnormalities of cardiac structure and function is unclear Albuminuria is a marker of subclinical renal damage in hypertension and it could be a parameter or a condition that directly causes cardiovascular disease or renal dysfunction et al. In addition to E/E′, NT-proBNP was correlated with GFR in univariate and multivariate analyses, consistent with the findings Van Kimmenade Despite the expanse of information known about cardiac structure and function in patients with ESRD 2, p = 0.02, data not shown). GFR was significantly correlated with the patients had a diabetes history , but had no relationship with the new-developed diabetes . In all the 42 diabetes patients, GFR had no relationship with diabetes . This result might be due to the high percentage of new-onset diabetes in our study.Diabetes may lead to chronic kidney disease and it can harm the kidney gradually, GFR gradually fall over a period of several years Abnormalities of pressure load characterizing early hypertension may result in both LV diastolic dysfunction and increased glomerular pressure and permeability, with resultant albuminuria A number of limitations of this analysis should be noted. First, since the present study is a cross-sectional study, we should observe the predictive value of E/E′ and NT-proBNP for renal dysfunction in a follow-up study. Furthermore, the current study was designed to assess associations between LV diastolic function and renal function but does not elucidate information on the mechanisms of this association.We confirmed that E/E′ was sensitive for detecting abnormal LV relaxation, especially in the relationship with renal function. Plasma NT-proBNP may be a potential biomarker, both in early LV diastolic dysfunction and renal dysfunction. LV diastolic function, assessed with E/E′ and NT-proBNP was associated with renal function in essential hypertension. Elevated E/E′ was associated with Stage 3 CKD and the presence of stage 3 CKD would inform the clinician to evaluate for the presence of LV diastolic dysfunction.


This study used CMR to evaluate patients with IHD prior to ICD implantation and correlated CMR measurements to VA inducibility and spontaneous VA events during follow-up. The results demonstrated that the gray-zone measurement using MCLE may be more sensitive in predicting appropriate ICD therapy for VA.In addition to measures of left ventricular ejection fraction (LVEF) and clinical staging of heart failure, myocardial infarct (MI) heterogeneity including MI and peri-infarct gray-zone (GZ) has the potential to predict the occurrence of inducible sustained ventricular arrhythmia (VA) and spontaneous VA events after implantation of implantable defibrillator (ICD) in patients with ischemic heart disease (IHD). Late-gadolinium (Gd)-enhancement (LGE) cardiac MR (CMR) using inversion-recovery fast-gradient-echo (IR-FGRE) is commonly used for the determination of infarct heterogeneity in these patients. Recently, a multi-contrast late-enhancement (MCLE) sequence has been developed for better infarct heterogeneity quantification. Compared to IR-FGRE, we hypothesized that MCLE may be a more sensitive method to predict the occurrence of inducible VA and severe events post-ICD implantation.This study used CMR to evaluate patients with IHD prior to ICD implantation and correlated CMR measurements to VA inducibility and spontaneous VA events during follow-up. The MRI protocol included LV functional parameter assessment using steady-state free precession (SSFP), as well as LGE-MRI using IR-FGRE and MCLE post double-dose Gd injection. LV functional parameters were measured using Q-Mass or CMR42 software. The GZ analysis in IR-FGRE used a full-width half-maximum method. For MCLE, GZ analysis used a semi-automated data clustering algorithm. An unpaired t-test with unequal variance was used for the statistical analysis of the proportion of GZ, MI core and total MI relative to LV myocardium mass.Twenty-five patients with IHD for planned ICD implantation  were enrolled. All patients completed the MRI protocol, ventricular electro-physiology study (EPS), and six months follow-up at the ICD clinic. Eight patients (32%) had inducible VA during programmed ventricular stimulation and six of these eight patients had at least one appropriate shock for VF from the ICD at follow-up. Another two patients without inducible VA had appropriate shocks from the ICD. CMR measurements of LVEF and myocardial infarct heterogeneity are shown in Tables CMR measurements of myocardial heterogeneity using MCLE and IR-FGRE are good predictors for the occurrence of inducible VA; however, the gray-zone measurement using MCLE may be more sensitive in predicting appropriate ICD therapy for VA.CIHR.


Our aim was to study the relationship between sACE2 activity, infarct size, left ventricular systolic function and remodeling following ST-elevation myocardial infarction (STEMI). A contrast-enhanced cardiac magnetic resonance study was performed acutely in 95 patients with first STEMI and repeated at 6 months to measure LV end-diastolic volume index, ejection fraction and infarct size. Baseline sACE2 activities, measured by fluorescent enzymatic assay 24 to 48 hours and at 7 days from admission, were compared to that obtained in 22 matched controls. Patients showed higher sACE2 at baseline than controls . At seven days, sACE2 activity significantly increased from baseline . An inverse correlation between sACE2 activity with acute and follow-up ejection fraction was observed . Additionally, sACE2 directly correlated with infarct size . Both, infarct size  and sACE2 at 7 days  were independent predictors of follow-up ejection fraction. Patients with sACE2 in the upper tertile had a 4.4 fold increase in the incidence of adverse left ventricular remodeling . In conclusion, serum sACE2 activity rises in relation to infarct size, left ventricular systolic dysfunction and is associated with the occurrence of left ventricular remodeling.Angiotensin-converting enzyme 2 (ACE2) cleaves Angiotensin-II to Angiotensin-(1–7), a cardioprotective peptide. Serum soluble ACE2 (sACE2) activity is raised in chronic heart failure, suggesting a compensatory role in left ventricular dysfunction The activation of the renin-angiotensin-aldosterone system (RAAS) is a well-known final pathway following ST-elevation-myocardial infarction (STEMI), leading to adverse left ventricular (LV) remodeling, heart failure and cardiac death. In addition to the cardioprotective effects provided by beta-blockers, it is well established that pharmacological blockade of the RAAS with Angiotensin-converting enzyme (ACE) inhibitors, Angiotensin-II receptor blockers or aldosterone antagonists limit LV remodeling and improve prognosis following STEMI Angiotensin-converting enzyme 2 (ACE2) is an analogue of the ACE that cleaves Angiotensin-II into Angiotensin-(1–7), a peptide with vasodilatory properties including an increase in coronary perfusion and attenuation of post-ischemic LV dysfunction that antagonizes angiotensin-II actions Recently, it has become feasible to measure soluble ACE2 (sACE2) activity in human serum, which allows the non-invasive study of this component of the RAAS. Serum sACE2 activity has been also shown to correlate with the presence and severity of heart failure among patients with ischemic and non-ischemic cardiomyopathy, to reinforce a cardioprotective and compensatory role in humans Both, the Hospital Clinic of Barcelona Research Committee and the Ethics Committee for Clinical Research approved this study. All participants and control subjects signed a consent form.th, 2009 to January 31st, 2010, 270 patients without prior history of cardiac disease were admitted to the Coronary Care Unit following STEMI. A total of 98 stable patients were immediately transferred to the referring hospital following reperfusion and were not assessed for this study. There were 8 early deaths and other 20 patients with clinical instability were excluded. In all, 144 patients were screened for their participation in the study. Further patient selection is detailed in From January 152, pH 7.5) in the presence of protease inhibitors, including 100 µM captopril, 5 µM amastatin, 5 µM bestatin , and 10 µM Z-Pro-prolinal (Enzo Life Sciences). Samples were incubated with 20 µM quenched fluorogenic substrate in reaction buffer  at 37°C. Specificity was determined by pre-incubating serum for 30 minutes with or without 0.6 µM DX600 , a specific ACE2 inhibitor The ACE2 fluorescent enzymatic assay protocol was performed as previously described with modifications, using an ACE2 quenched fluorogenic substrate (Mca-Ala-Pro-Lys(Dnp)-OH, Enzo Life Sciences) To explore whether sACE2 release was related to a membrane shedding effect, we measured serum levels of tumor necrosis factor-∝ converting enzyme ADAM17 using DuoSet ELISA development kit  and following manufacturer’s instructions A standard ce-CMR study was performed in a 1.5 T clinical scanner  equipped with cardiac-dedicated software at a mean of 6.3±3.4 (range: 3 to 10) days of admission and repeated at 6.4±1.0 month. LV function was assessed using a steady-state free-precession cine sequence prescribed in sequential 10-mm short axis slices with no gap from base to apex to achieve full LV coverage. The myocardium at risk was assessed by edema imaging using a dark-blood T2W-SE triple inversion recovery sequence in the same short-axis positions. Delayed-enhanced images were acquired 10 to 15 min after intravenous administration of gadodiamide-DTPA  at a dose of 0.2 mmol/Kg using a standard segmented inversion-recovery fast gradient-echo pulse sequence. The inversion time was adjusted to null normal myocardium, typically between 180 and 320 msec. Matrix size was set to 256 and the mean field of view was 360 mm, resulting in a typical voxel size of 1.4 by 1.4 by 10 mm. All CMR images were cropped and de-identified for analysis by an independent experienced observer blinded to all clinical and angiographic data. The endocardial and epicardial borders on sequential short axis cine images were manually traced to compute LV end-systolic volume index (ESVi) and end-diastolic volume index (EDVi) as well as LV ejection fraction (EF) using Argus® software . The hyperenhanced regions on T2 W images were manually delineated in all short axis slices to compute the myocardium at risk as a percentage of the LV wall. In 32 cases with insufficient image quality or poor signal-to-noise contrast, we used the angiographic BARI score as a surrogate of area at risk as previously reported A self-customized tool based in MATLAB platform  was used to compute the infarct size. First, the endocardial and epicardial borders were manually traced on short-axis contrast-enhanced images. Similarly, an experienced observer roughly outlined the hyperenhanced myocardium, and those areas were post-processed with an algorithm to define the infarcted myocardium according to the half-maximum pixel intensity criteria th–75th percentiles] as well as time-to-reperfusion. Other quantitative data were expressed as mean and standard deviation. Categorical data were summarized as frequencies and percentages, and differences between groups were assessed using the chi-squared test. Comparisons of sACE2 activity between groups were performed using the non-parametric Mann-Whitney U test, and differences over time within subjects were evaluated by paired analysis. Bivariate associations between ACE2 activity, infarct size and other quantitative variables were assessed by the Spearman’s correlation coefficient. One-way analysis of variance was used among sACE2 intertertile range for the various clinical parameters. A multivariate linear regression model was constructed to identify independent significant predictors of final EF, including logarithmic-transformed ACE2 activity and other significant univariate predictors. In order to assess infarct size variability, two independent observers measured 40 randomly selected studies twice. The Lin’s concordance correlation coefficient was 0.96  for intraobserver variability and 0.92 . SPSS version 15.0 for Windows was used, and a p value <0.05 was considered statistically significant for all tests used.Normality plots and Shapiro-Wilkoxon’s test confirmed the non-normality distribution of sACE2 activity data. Accordingly, enzymatic activities were expressed as median [25Patients (n = 95) and controls (n = 22) were well matched for sex, age, and risk factors . The cliWe found sACE2 activity at 7 days to be increased in 19 patients in Killip class 2 or 3 during admission as compared to patients in Killip 1 . The results were similar when only the angiographic measurements of myocardium at risk where taken into account for all patients. Infarct size derived from ce-CMR weakly correlated with sACE2 activity at 7 days  and 6 months follow-up , . sACE2 aSerum ADAM17 was not significantly different between controls and patients at baseline . ADAM17 was not correlated with sACE2 activity at baseline  or 7 days . We found no association between serum ADAM17 and infarct size by ce-CMR at 7 days  or 6 months .Infarct size by ce-CMR  or peak troponins , MO score , the initial BNP , sACE2 at 7 days  and the myocardium at risk  were univariate predictors of late EF. Although many variables including myocardium at risk, infarct size, MO extent, ACE2 activity and BNP correlated with LV ESDi and EDVi at baseline and follow-up, ACE2 activity was the only predictor of % increase in EDVi . Fifteen (16.9%) subjects presented adverse LV remodeling at follow-up, defined as an increase ≥20% in the follow-up EDVi as compared to baseline. They had increased ACE2 activity at 7 days . However, infarct size and MO extent were not significantly different between both groups . Neither BNP nor peak troponins were different in both groups  against Angiotensin-II actions. Measurements of circulating Angiotensin-II or Angiotensin 1–7 were not available and therefore, our study do not provide the mechanism for the supposed protective role of ACE2 in STEMI, that will need further evaluation. We performed the initial CMR a mean of 6 days after the index event, when most of LV remodeling has probably occurred. In addition, we did not include clinically unstable patients in whom the ce-CMR study could not be performed. Those are the patients with more adverse remodeling and larger infarct size. These facts might have limited the true relationship found between infarct size, LV remodeling and sACE2 activity. As a result, the correlations found between sACE2, infarct size, LV EF or remodeling were modest. However, our purpose was to demonstrate a relationship between ACE2 activation and LV dysfunction to support future therapeutic developments rather than using the measure as a clinical tool to predict adverse remodeling.To our knowledge, this is the first study reporting that sACE2 activity is increased in the acute phase of STEMI in humans and correlates with the extent of jeopardized myocardium and infarct size. ACE2 activity measured acutely seems to be an independent predictor of late LV systolic function and it is also associated with the occurrence of adverse remodeling. Further pathophysiological and mechanistic studies are warranted to elucidate whether this association, that has been shown to be present in several cardiac conditions causing left ventricular dysfunction, may become a new target for therapy following STEMI.Table S1CMR characteristics of patients with adverse LV remodeling on follow-up as compared to the remaining.(DOC)Click here for additional data file.