Evaluation of the myocardial deformation in the diagnosis of rejection after heart transplantation

Introduction

Heart transplantation represents main therapy for end-stage heart failure. However, survival after transplantation is limited by development of graft rejection. Endomyocardial biopsy, an invasive and expensive procedure, is gold standard technique for diagnosis of rejection. Most of biopsy complications are observed using echocardiography. Novel echocardiographic techniques, such as myocardial strain and three-dimensional reconstruction, can be useful in heart transplant patients.

Purpose

To evaluate ventricular strain in heart transplant patients and association with rejection, cellular or humoral, as well as two- and three-dimensional echocardiographic parameters.

Methods

Cohort of patients from heart transplant program taken to echocardiography after endomyocardial biopsy, from December 2017 to January 2020. Ventricular strain and three-dimensional left ventricle parameters were studied. Rejection results were retrieved from medical record. Qualitative variables were expressed by absolute frequency and percentages, while continuous variables by means and standard deviations. Association between rejection and variables of interest was measured by odds ratio and confidence interval of 95%, with p-value < 0.05.

Results

123 post-endomyocardial biopsy echocardiographic exams were performed in 54 patients. Eighteen exams were excluded, lasting 105 exams to be evaluated for conventional and advanced echocardiographic parameters. Male patients were 60.4%. Prevalence of cellular rejection was 8.6%, humoral rejection 12.4%, and rejection of any type 20%. There was no association between right ventricular strain and rejection, whether cellular (p = 0.118 and p = 0.227 for septum and free wall, respectively), humoral (p = 0.845 and p = 0.283, respectively), or of any type (0.504 and 0.446). There was no correlation between rejection and left ventricle global longitudinal strain, three-dimensional ejection fraction or desynchrony index. Conventional parameters associated to rejection were left ventricle posterior wall thickness [OR 1.660 (1.163; 2.370), p = 0.005] and left ventricle mass index [OR 1.027 (1.011; 1.139), p = 0.001]. Left ventricle posterior wall thickness remained significant after analysis of cellular and humoral rejection separately [OR 1.825 (1.097; 3.036), p = 0.021 and OR 1.650 (1.028; 2.648), p = 0.038, respectively].

Conclusions

There was no association between ventricular strain, three-dimensional left ventricular ejection fraction and the desynchrony index and rejection, cellular or humoral. Evidence of association of graft rejection with left ventricle posterior wall thickness and left ventricle mass index was observed.

Diagnostic and Prognostic Value of a TDI-Derived Systolic Wall Motion Analysis as a Screening Modality for Allograft Rejection after Heart Transplantation

Background: Despite the risk for complications, allograft surveillance after orthotopic heart transplantation (OHT) is performed by cardiac catheterization and biopsies. We investigated the diagnostic and prognostic value of a TDI-derived systolic wall motion analysis of the posterobasal wall of the left ventricle (Sm) as a screening modality in OHT aftercare. Methods: We examined data of 210 eligible patients who underwent OHT between 2010 and 2020. Forty-four patients who had died within the initial hospital stay were excluded. For 166 patients, baseline and follow-up data were analyzed. The mean age at OHT was 46.2 (±11.4) years; 76.5% were male. Results: Within the observational period, 22 (13.3%) patients died. In total, 170 episodes of acute cellular or humoral rejections occurred (84 ISHLT1R; 13 ISHLT2R; 8 ISHLT3R; 65 AMR), and 29 catheterizations revealed cardiac allograft vasculopathy (5 CAV1; 4 CAV2; 20 CAV3). Individual Sm radial/longitudinal remained stable within the follow-up period (11.5 ± 2.2 cm/s; 10.9 ± 2.1 cm/s). Patients with acute rejections and CAV3 showed significant Sm radial/longitudinal reductions (AMR1: 1.6 ± 1.9 cm/s, confidence interval (CI) 0.77–0.243, p < 0.001; 1.8 ± 2.0 cm/s, CI 0.92–0.267, p < 0.001. ISHLT1R: 1.7 ± 1.8 cm/s, CI 1.32–2.08, p < 0.001; 2.0 ± 1.6 cm/s, CI 1.66–2.34, p < 0.001. CAV3: 1.3 ± 2.5 cm/s, CI 0.23–2.43, p < 0.017; 1.4 ± 2.8 cm/s, CI 0.21–2.66, p < 0.021). Lower Sm was associated with a threefold increase in all-cause mortality (hazard ratio (HR) 3.24, CI 1.2–8.76, p = 0.020; HR 2.92, CI 1.19–7.18, p = 0.019). Overall, Sm-triggered surveillance led to 0.75 invasive diagnostics per patient post-OHT year. Conclusions: Sm remained stable in the post-OHT course. Reductions indicated ISHLT1R, AMR1 and CAV3 and were associated with higher all-cause mortality. Sm-triggered surveillance may be referred to as a safe, high-yield screening modality in OHT aftercare.

Global longitudinal strain in heart transplantation recipients using different vendors: reliability and validity in a tertiary hospital in Colombia

Global Longitudinal Strain (GLS) is a useful tool to follow-up heart transplant (HT) recipients. Important inter-vendor variability of GLS measurements has been reported in healthy subjects and different conditions, but there is still limited evidence among HT patients. We assessed the reliability and validity of GLS using two vendors (General Electric and Philips) in a group of consecutive and stable adult HT recipients. Patients underwent two concurrent GLS analyses during their echocardiographic follow-up. We evaluated GLS inter-vendor reliability using Bland-Altman's limits of agreement (LOA) plots, computing its coverage probability (CP) and the intraclass correlation coefficient (ICC). Validity was assessed though receiver operating characteristics (ROC) curves, predictive values, sensitivity and specificity of GLS for each vendor to detect a normal left ventricle function. 78 pairs of GLS studies in 53 stable HT patients were analyzed. We observed a modest inter-vendor reliability with a broad LOA (less than 50% of values falling out our CP of 2% and an ICC of 0.49). ROC analyses (areas under the curve of 0.824 Vs. 0.631, p < 0.05) and diagnosis test indices (Sensitivity of 0.73 Vs. 0.64; and Specificity of 0.79 Vs. 0.50) favored GE over Philips. Inter-vendor variability for GLS analysis exceeded clinically acceptable limits in HT recipients. GLS from GE software seemed to show higher validity as compared to Philips'. The present study provides evidence to consider caution for the interpretation of GLS for clinical management in the follow-up of HT patients, especially when GLS is measured by different vendors.

Imaging of Cardiac Transplantation: An Overview

Heart transplantation (HTx) remains the optimal treatment for selected patients with end-stage advanced heart failure. However, survival is limited early by acute rejection and long term by cardiac allograft vasculopathy (CAV). Even though the diagnosis of rejection is based on histology, cardiac imaging provides a pivotal role for early detection and severity assessment of these hazards. The present review focuses on the use and reliability of different invasive and non-invasive imaging modalities to detect and monitor CAV and rejection after HTx. Coronary angiography remains the corner stone in routine CAV surveillance. However, angiograms are invasive and underestimates the CAV severity especially in the early phase. Intravascular ultrasound and optical coherence tomography are invasive methods for intracoronary imaging that detects early CAV lesions not evident by angiograms. Non-invasive imaging can be divided into myocardial perfusion imaging, anatomical/structural imaging and myocardial functional imaging. The different non-invasive imaging modalities all provide clinical and prognostic information and may have a gatekeeper role for invasive monitoring. Acute rejection and CAV are still significant clinical problems after HTx. No imaging modality provides complete information on graft function, coronary anatomy and myocardial perfusion. However, a combination of invasive and non-invasive modalities at different stages following HTx should be considered for optimal personalized surveillance and risk stratification.

Predictive Parameters of Decreased Left Ventricular Global Longitudinal Strain at 1 Month After Pediatric Heart Transplantation

Previous reports indicate that the decreased left ventricular global longitudinal strain (LVGLS) seen in the early postoperative period of pediatric heart transplant patients generally recovers over the course of 1-2 years. In this study, we investigate the predictive capacity of preoperative parameters on the LVGLS decline seen at 1 month post transplant. Forty-six transplant subjects with 2D echocardiographic images sufficient for speckle tracking echocardiography were enrolled. We excluded patients diagnosed with cardiac allograft vasculopathy or with an episode of rejection 1 month before or after their echocardiographic examinations. The mean LVGLS was significantly reduced at 1 month when compared to 1 year following transplant (- 15.5% vs. - 19.4%, respectively, p < 0.001). The predictors of LVGLS that decline at 1 month were the LV mass z-score [odds ratio (OR) 1.452; 95% confidence interval (CI) 1.007-2.095, p = 0.046], recipient age (OR 1.124; 95% CI 1.015-1.245, p = 0.025), and donor age (OR 1.081; 95% CI 1.028-1.136, p = 0.002) in the univariate logistic regression analyses. Although multivariate analysis yielded no significant predictors, higher LV mass z-scores showed a trend associated with the decline of LVGLS (p = 0.087). The donor/recipient weight ratio was associated with the LV mass z-score (R² = 0.412, p < 0.001).

Longitudinal Strain and Strain Rate for Estimating Left Ventricular Filling Pressure in Heart Transplant Recipients

Traditional parameters have limited value to estimate left ventricular filling pressure (LVFP) in orthotropic heart transplant (OHT) recipients. We hypothesized that global longitudinal strain (GLS), diastolic, and systolic strain rate (SR) would be depressed in OHT recipients with elevated LVFP and could overcome the limitations of traditional parameters. We studied consecutively OHT patients at the time of endomyocardial biopsies and retrospectively pretransplantation studies conforming to the same protocol. Comprehensive echocardiography with strain measurements was performed. Results were compared with pulmonary capillary wedge pressure (PCWP) obtained from right heart catheterization that was performed just after the echocardiography study. In all, 74 studies were performed in 50 OHT recipients. Mean PWCP was 11.8 ± 4.3 mm Hg (range: 4 to 25 mm Hg). Several parameters, but not left atrial volume index, mitral inflow velocities, annular velocities, and their ratio (E/e'), were different between studies with normal (n = 47) and elevated PCWP (n = 27). Area Under Curve for GLS (0.932*), E/e'_SR (0.849*), and systolic SR (0.848*) (*p <0.0001) were more accurate than traditional parameters for predicting PCWP>12 mm Hg. GLS, systolic SR and E/e'_SR remained accurate regardless of LV ejection fraction and allograft vasculopathy. Meanwhile, E/e' was accurate to predict PWCP in native failing hearts before transplantation. Changes in GLS and E/e'_SR tracked accurately changes in PCWP. In conclusion, traditional indices of diastolic function perform poorly in OHT recipients, whereas GLS and E/e'_SR provide reliable means of LVFP, irrespective of ejection fraction and allograft vasculopathy. These parameters also track reasonably well the changes in LVFP.

Assessment of biventricular function by three-dimensional speckle-tracking echocardiography in clinically well pediatric heart transplantation patients

BACKGROUND

The biventricular function plays an important role in the prognosis of pediatric heart transplantation (HTx) patients. Therefore, in this study, we aimed to evaluate the biventricular function of pediatric HTx patients by three-dimensional (3D) speckle-tracking echocardiography (3D-STE).

METHODS

We enrolled 30 clinically well pediatric HTx patients and 30 healthy controls with a similar distribution of sex and age to the HTx. All participants underwent comprehensive two-dimensional (2D) and 3D echocardiography. Left ventricular (LV) global longitudinal strain (GLS), global circumferential strain (GCS), left and right ventricular ejection fraction (LVEF and RVEF, respectively), and right ventricular free wall longitudinal strain (RV FWLS) were acquired by 3D-STE. Moreover, the correlations between strains and clinical data were explored.

RESULTS

Compared with controls, LV GLS was decreased in pediatric HTx patients (P < .05), while LV GCS and LVEF showed no difference. LV GLS showed a weak correlation with cold ischemic time in HTx group (r = 0.396, P < .05). Meanwhile, RVEF and RV FWLS were significantly lower in the HTx group (P < .05). In the HTx group, RV FWLS showed a weak correlation with the preoperative mean pulmonary artery pressure (r = 0.420, P < .05) and postoperative pulmonary artery systolic pressure (r = 0.465, P < .05).

CONCLUSION

The 3D-biventricular mechanical functions were decreased in clinically well pediatric HTx patients. The provided characteristics and appropriate normal values of biventricular mechanical functions can be the basis in subsequent studies in the pediatric HTx patients.

Heart transplantation ten-year follow-ups: Deformation differentiation comparison of myocardial performance in left ventricle and right ventricle

BACKGROUND

We try to investigate whether the values of three-dimensional principal longitudinal strain present differently between the left and right ventricles in patients with long-time follow-ups after heart transplantation (HTx).

METHODS AND RESULTS

Transthoracic echocardiography with three-dimensional speckle tracking was performed at one-, five- and ten-year follow-ups in 62 "healthy" HTx patients together with routine echocardiographic evaluation in 32 control group (CG) individuals. Longitudinal strain was applied in all subjects assessing without myocardium wall motion abnormality. Firstly, left ventricular ejection fraction preserved in HTx and had no significant difference in comparison with the controls (p > .05). 3D measurement showed obvious reduction in global (%: CG: -20.5 ± 3.5 vs. HT1y: -13.7 ± 4.6, HT5y: -14.4 ± 4.5, HT10y: -14.6 ± 4.7. p < .01) and horizontal segmental (basal, mid, apical, CG vs. HTx: all p < .01) strain values of the left compared HTx with control subjects. Secondly, tissue Doppler imaging s' velocity and tricuspid annular plane systolic excursion reduced in HTx as compared to the controls in right ventricle (p < .01). Longitudinal strain presented a more distinctive reduction in global (%: CG: -24.5 ± 4.6 vs. HT1y:-14.8 ± 7.5, HT5y: -15.5 ± 6.4, HT10y: -15.9 ± 6.8. p < .01) and horizontal segmental (basal, mid, apical, CG vs. HTx: all p < .01) average values of the right compared HTx with control subjects. Thirdly, there weren't any significant changes between one-, five- and ten-year of all the values with HTx inter-group comparison in both the left and right ventricles (p > .05). Fourthly, the global and segmental strain of the right ventricle decreased more than that of the left ventricle in all HTx groups, with the global decreased differentiation rates of 7%, 7%, 6%, respectively.

CONCLUSIONS

Compared HTx with control subjects in both ventricles, conventional evaluation showed preserved or decreased functions in the left and right separately. Myocardial function evaluating by 3D longitudinal strain reduced after HTx, but the deformation of the right ventricle reduced more than those of the left ventricle. Additionally, 3D strain values almost remained with stable decreased differentiation rates during the long-time follow-ups.

Altered Biatrial Phasic Function after Heart Transplantation in Children

PURPOSE

We used two-dimensional echocardiographic speckle-tracking to investigate whether left and right atrial (LA and RA) phasic function in pediatric heart transplantation (HT) patients is altered and explored the relationship to HT-related clinical variables.

METHODS

Eighty-six subjects (36 HT and 50 normal children) were prospectively enrolled in two centers. Clinical data included age at HT, bypass time, ischemia time, donor age, and incidence of rejection. Atrial deformation indices including strain and strain rates (SRs) were measured using two-dimensional echocardiographic speckle-tracking. Components of phasic atrial function-reservoir (ε_r, SR_r), conduit (ε_cd, SR_cd), and booster (ε_ct, SR_ct) were calculated. Comparisons with controls were made using t test or Kruskal-Wallis test, and correlations to clinical variables were explored.

RESULTS

The mean age and body surface area of HT subjects were 10.2 ± 6.2 years and 1.2 ± 0.6 m², respectively. The mean heart rates were higher in HT (96 ± 18 vs 88 ± 21 in controls). There were reductions in RA and LA reservoir (ε_r, SR_r), conduit (ε_cd, SR_cd), and booster (ε_ct, SR_ct) function in HT compared with controls. There was no relationship of LA and RA deformation indices with mean age at HT, bypass time, or ischemia time. The LA ε_cd correlated weakly with donor age (r = -0.49, P = .04) and RA SR_r, and SR_cd showed association with duration of HT (P < .05). Nineteen HT recipients had follow-up studies 0.24 ± 0.18 years after the first examination, and deformational indices were not significantly changed.

CONCLUSIONS

Atrial strain determination is feasible in pediatric HT recipients and demonstrates disruption of reservoir, conduit, and booster function of both atria in this population; we speculate this may be a consequence of ventricular diastolic dysfunction.

Left and right ventricular function detection and myocardial deformation analysis in heart transplant patients with long-time follow-ups

OBJECTIVE

We try to investigate whether the values of longitudinal strain present differences between the left and right ventricles in long-time follow-ups after heart transplantation (HTx) with dynamic changes in function.

METHODS AND RESULTS

Follow-up transthoracic echocardiography was performed in 1- and 3-month and 1- and 5-year follow-ups in 50 "healthy" HTx patients and compared with 26 control subjects. The left ventricle with preserved ejection fraction evaluated by biplane Simpson (control group [CG] vs HT; P > .05) had an obvious reduction in global (CG: -20.49 ± 2.38 vs heart transplant 1 month [HT1m]: -13.06 ± 2.86, heart transplant 3 month [HT3m]: -13.61 ± 2.61, heart transplant 1 year [HT1y]: -13.69 ± 4.56, heart transplant 5 year [HT5y]: -14.41 ± 4.54; P < .001) and horizontal segmental (basal, mid, apical) (P < .001) together with chamber segmental (apical 4-chamber, apical 3-chamber, apical 2-chamber) (P < .001) average strain values. The right ventricle with reduced ventricular function measured by tissue Doppler imaging S' and tricuspid annular plane systolic excursion had a more distinctive reduction in global (CG: -24.53 ± 4.20 vs HT1m: -12.94 ± 5.03, HT3m: -13.68 ± 4.35, HT1y: -14.95 ± 7.50, HT5y: -15.20 ± 6.15; P < .001) with segmental lateral (P < .001) strain values. There were not any significant changes between 1- and 3-month follow-ups of all the values (P > .05). But it could be seen that values increased in 1- and 5-year follow-ups compared with the baseline of 1- and 3-month follow-ups (P < .05). The global and segmental strain of the right ventricle decreased more than that of the left ventricle in all HTx groups, and the strain values were decreased in the HTx groups compared with the CG, with the global decreased change rates being 11%, 10%, 6%, and 8%, respectively.

CONCLUSIONS

The strain values decreased after HTx and almost remained stable in the long-time follow-ups. Compared with the CG in both ventricles, they were with preserved or reduced functions. In addition, the deformation values of the right ventricle decreased more than those of the left.

Temporal changes in left ventricular strain with the development of rejection in paediatric heart transplant recipients

INTRODUCTION

Myocardial strain measurements are increasingly used to detect complications following heart transplantation. However, the temporal association of these changes with allograft rejection is not well defined. The aim of this study was to describe the evolution of strain measurements prior to the diagnosis of rejection in paediatric heart transplant recipients.

METHODS

All paediatric heart transplant recipients (2004-2015) with at least one episode of acute rejection were identified. Longitudinal and circumferential strain measurements were assessed at the time of rejection and retrospectively on all echocardiograms until the most recent negative biopsy. Smoothing technique (LOESS) was used to visualise the changes of each variable over time and estimate the time preceding rejection at which alterations are first detectable.

RESULTS

A total of 58 rejection episodes were included from 37 unique patients. In the presence of rejection, there were decrements from baseline in global longitudinal strain (-18.2 versus -14.1), global circumferential strain (-24.1 versus -19.6), longitudinal strain rate (-1 versus -0.8), circumferential strain rate (-1.3 versus -1.1), peak longitudinal early diastolic strain rate (1.3 versus 1), and peak circumferential early diastolic strain rate (1.5 versus 1.3) (p<0.01 for all). The earliest detectable changes occurred 45 days prior to rejection with simultaneous alterations in myocardial strain and ejection fraction.

CONCLUSIONS

Changes in graft function can be detected non-invasively prior to the diagnosis of rejection. However, changes in strain occur concurrently with a decline in ejection fraction. Strain measurements aid in the non-invasive detection of rejection, but may not facilitate earlier diagnosis compared to more traditional measures of ventricular function.

Use of speckle-tracking echocardiography-derived strain and systolic strain rate measurements to predict rejection in transplant hearts with preserved ejection fraction

BACKGROUND

Noninvasive diagnosis of allograft rejection in heart transplant recipients is challenging. The utility of 2-dimensional speckle-tracking echocardiography (2D-STE) to predict severe rejection in heart transplant recipients with preserved left ventricular ejection fraction (LVEF) was evaluated.

METHODS

Adult heart transplant patients with preserved LVEF (> 55%) and severe rejection by biopsy (Rejection Grade ≥ 2R) or no rejection between 1997 and 2011 at the Mayo Clinic in Rochester, Minnesota were evaluated. Transthoracic echocardiography was performed within 1 month of the biopsy. LV global longitudinal and circumferential strain and strain rates (GLS, GLSR, GCS, and GCSR) were analyzed retrospectively.

RESULTS

Of 65 patients included, 25 had severe rejection and 40 were normal transplant controls without rejection. Both groups had more men than women (64 and 75%, respectively). Baseline clinical variables were similar between the groups. Both groups had normal LVEF (64.3% vs 64.5%; P = .87). All non-strain echocardiographic variables were similar between the 2 groups. Strain analysis showed significantly increased early diastolic longitudinal strain rate (P = .02) and decreased GCS (P < .001) and GCSR (P = .02) for the rejection group compared with the control group. The area under the receiver operating characteristic curve for GCS was 0.77. With a GCS cutoff of - 17.60%, the sensitivity and specificity of GCS to detect severe acute rejection were 81.8 and 68.4%, respectively.

CONCLUSIONS

2D-STE may be useful in detecting severe transplant rejection in heart transplant patients with normal LVEF.

Changes in left ventricular strain parameters following pediatric heart transplantation

STE is increasingly utilized to assess strain in a variety of pathologies. Strain measurements have demonstrated utility following HTx and may aid in the detection of rejection and CAV. Strain parameters have not been well defined in the pediatric HTx population. This study aimed to describe strain in pediatric HTx recipients compared to controls and assess changes over time. All pediatric HTx recipients with available echocardiograms (2004-2015) without rejection or CAV were identified. Longitudinal and circumferential strain was measured at <1 month, 1 year, 3 years, and 5 years post-transplant and compared to controls. A total of 218 echocardiograms were analyzed in 79 HTx recipients. At <1 month post-transplant, there was a significant decrement in longitudinal strain (GLS -14.6 vs -19.2, P < .001) with concurrent augmentation of circumferential strain (GCS -27.3 vs -24.3, P = .005). By 1 year post-HTx, all strain parameters normalized and were not significantly different from the control population. In the absence of graft complications, strain parameters did not change up to 5 years post-transplant. Abnormal longitudinal strain parameters are present in the early post-HTx period with a compensatory increase in circumferential strain. These changes normalize by 1 year post-transplant and do not change over time in the absence of graft complications.

Long-term prognostic value of invasive and non-invasive measures early after heart transplantation

BACKGROUND

Invasively assessed coronary microvascular resistance early after heart transplantation predicts worse long-term outcome; however, little is known about the relationship between microvascular resistance, left ventricular function and outcomes in this setting.

METHODS

A total of 100 cardiac transplant recipients had fractional flow reserve (FFR) and the index of microcirculatory resistance (IMR) measured in the left anterior descending artery and echocardiographic assessment of left ventricular ejection fraction (LVEF) and global longitudinal strain (GLS) at 1 year after heart transplantation. The primary endpoint was the composite of death and retransplantation occurring beyond the first post-operative year.

RESULTS

The mean FFR, IMR, LVEF, and GLS values at 1 year were 0.87 ± 0.06, 21.3 ± 17.3, 60.4 ± 5.4%, and 14.2 ± 2.4%, respectively. FFR and IMR had no significant correlation with LVEF and GLS. During a mean follow-up of 6.7 ± 4.2 years, the primary endpoint occurred in 24 patients (24.0%). By ROC curve analysis, IMR = 19.3 and GLS = 13.3% were the best cutoff values for predicting death or retransplantation. Cumulative event-free survival was significantly lower in patients with higher IMR (log-rank p = 0.02) and lower GLS (log-rank p < 0.001). Cumulative event-free survival can be further stratified by the combination of IMR and GLS (long-rank p < 0.001). By multivariable Cox proportional hazards model, higher IMR and lower GLS were independently associated with long-term death or retransplantation (elevated IMR, hazard ratio = 2.50, p = 0.04 and reduced GLS, hazard ratio = 3.79, p = 0.003, respectively).

CONCLUSION

Invasively assessed IMR does not correlate with GLS at 1 year after heart transplantation. IMR and GLS determined at 1 year may be used as independent predictors of late death or retransplantation.

Dominance of free wall radial motion in global right ventricular function of heart transplant recipients

Assessment of right ventricular (RV) function using conventional echocardiography might be inadequate as the radial motion of the RV free wall is often neglected. Our aim was to quantify the longitudinal and the radial components of RV function using three-dimensional (3D) echocardiography in heart transplant (HTX) recipients. Fifty-one HTX patients in stable cardiovascular condition without history of relevant rejection episode or chronic allograft vasculopathy and 30 healthy volunteers were enrolled. RV end-diastolic (EDV) volume and total ejection fraction (TEF) were measured by 3D echocardiography. Furthermore, we quantified longitudinal (LEF) and radial ejection fraction (REF) by decomposing the motion of the RV using the ReVISION method. RV EDV did not differ between groups (HTX vs control; 96 ± 27 vs 97 ± 2 mL). In HTX patients, TEF was lower, however, tricuspid annular plane systolic excursion (TAPSE) decreased to a greater extent (TEF: 47 ± 7 vs 54 ± 4% [-13%], TAPSE: 11 ± 5 vs 21 ± 4 mm [-48%], P < .0001). In HTX patients, REF/TEF ratio was significantly higher compared to LEF/TEF (REF/TEF vs LEF/TEF: 0.58 ± 0.10 vs 0.27 ± 0.08, P < .0001), while in controls the REF/TEF and LEF/TEF ratio was similar (0.45 ± 0.07 vs 0.47 ± 0.07). Current results confirm the superiority of radial motion in determining RV function in HTX patients. Parameters incorporating the radial motion are recommended to assess RV function in HTX recipients.

Normal Reference Ranges for Transthoracic Echocardiography Following Heart Transplantation

BACKGROUND

Heart function following heart transplantation (HTx) is influenced by numerous factors. It is typically evaluated using transthoracic echocardiography, but reference values are currently unavailable for this context. The primary aim of the present study was to derive echocardiographic reference values for chamber size and function, including cardiac mechanics, in clinically stable HTx patients.

METHODS

The study enrolled 124 healthy HTx patients examined prospectively. Patients underwent comprehensive two-dimensional echocardiographic examinations according to contemporary guidelines. Results were compared with recognized reference values for healthy subjects.

RESULTS

Compared with guidelines, larger atrial dimensions were seen in HTx patients. Left ventricular (LV) diastolic volume was smaller, and LV wall thickness was increased. With respect to LV function, both ejection fraction (62 ± 7%, P < .01) and global longitudinal strain (-16.5 ± 3.3%, P < .0001) were lower. All measures of right ventricular (RV) size were greater than reference values (P < .0001), and all measures of RV function were reduced (tricuspid annular plane systolic excursion 15 ± 4 mm [P < .0001], RV systolic tissue Doppler velocity 10 ± 6 cm/sec [P < .0001], fractional area change 40 ± 8% [P < .0001], and RV free wall strain -16.9 ± 4.2% [P < .0001]). Ejection fraction and LV global longitudinal strain were significantly lower in patients with previous rejection.

CONCLUSION

The findings of this study indicate that the distribution of routinely used echocardiographic measures differs between stable HTx patients and healthy subjects. In particular, markedly larger RV and atrial volumes and mild reductions in both LV and RV longitudinal strain were evident. The observed differences could be clinically relevant in the assessment of HTx patients, and specific reference values should be applied in this context.

Serial changes in longitudinal graft function and implications of acute cellular graft rejections during the first year after heart transplantation

AIMS

The aim of this prospective study was to use left ventricular global longitudinal strain (LV-GLS) as a non-invasive tool for the monitoring of graft function in relation to acute cellular rejection (ACR) during the first year after heart transplantation (HTX).

METHODS AND RESULTS

The study population consisted of 36 patients undergoing HTX from November 2010 until October 2013. Patients were followed by comprehensive echocardiography and biopsies at 2 weeks and 1, 3, 6, and 12 months after HTX. ACRs were classified based on the ISHLT classification (0R-3R). Patients were divided into two groups according to the presence of one or more episodes of biopsy proven ≥grade 2R ACR during follow-up. We found that LV-GLS and tricuspid annular plane systolic excursion (TAPSE) were significantly related to ACR burden in a linear regression model. The absolute difference in LV-GLS between patients in the ACR group (-14.4%) and patients in the ACR-free group (-16.8%) was -2.4% (P < 0.01) 12 months after HTX. In the ACR group, patients' LV-GLS did not improve between 1 and 12 months, whereas an improvement of -2.9% was seen in the ACR-free group in this period (P < 0.01). The two groups appeared not to differ in terms of diastolic Doppler parameters or LV ejection fraction, but TAPSE was 15.3 ± 2.8 mm in the ACR-free group vs. 13.2 ± 2.1 mm ACR group, P < 0.05, 12 months after HTX.

CONCLUSION

Gradual improvement of longitudinal LV and RV function was seen within the first year after HTX, but the degree of recovery was strongly influenced by ACR episodes.

Cardiac mechanics in heart transplant recipients with and without transplant vasculopathy

Evaluation of cardiac mechanics in heart transplant recipients (HTR) is of paramount importance. Assessment of strain through echocardiography is suited to describe cardiac function and might allow characterizing patients with and without transplant vasculopathy (TVP) a risk factor of impaired organ function and rejection. For this study 41 HTR immediately after and 1-3 years after transplantation were examined in a retrospective approach with 2-dimensional speckle tracking echocardiography to assess longitudinal, radial and circumferential strain and strain rate. The cohort consists of 33 men and 8 women with a median age of 54 years (1st, 3rd; 45.7, 65.3) with seven cases diagnosed with TVP during follow-up, as diagnosed by coronary angiography. The overall cohort showed an improvement of global longitudinal strain from baseline to 1 and 3 years with -14.2% (-16.9, -12.3%) to -16.1% (-17.5, -14.3%) and -16.7% (-18, -13.7%), p = 0.036. For patients developing TVP, global longitudinal strain was not different from baseline up to the maximum of 3 years -16.6% (-16.7-13.8%) to -16.4% (-17.3, -14.7%) and -17.6% (-18.7, -16.9%) with p = 0.21. Radial strain and torsion showed a trend to decrease after transplantation with time. Circumferential strain remained stable in HTR but decreased in subjects with TVP. Longitudinal Strain and strain rate showed no relevant changes in HTR with and without TVP. Radial strain and torsion declined in HTR as well as TVP patients with time. Speckle tracking imaging is useful to assess organ function in HTR, however coronary angiography is still needed to rule out TVP.

Similarities in coronary function and myocardial deformation between psoriasis and coronary artery disease: the role of oxidative stress and inflammation

BACKGROUND

Psoriasis has been associated with increased risk for coronary artery disease (CAD). We investigated the presence of vascular and subclinical left ventricular (LV) dysfunction in patients with psoriasis compared with patients with CAD.

METHODS

We compared 59 patients with psoriasis without evidence of CAD (psoriasis area and severity index [PASI], 11.5 ± 8) with 59 patients with angiographically documented CAD and 40 controls. We measured (1) the carotid-femoral pulse wave velocity (PWVc) and central augmentation index (CAI), (2) coronary flow reserve (CFR) by Doppler echocardiography, (3) flow-mediated dilation (FMD) of the brachial artery and carotid intima media thickness (IMT), (4) LV global longitudinal strain (GLS) and GLS rate (GLSR) using speckle tracking echocardiography, and (5) malondialdehyde (MDA) and interleukin-6 (IL-6) levels.

RESULTS

Patients with psoriasis had higher PWVc, CAI, IMT, MDA, and IL-6 levels and lower FMD, CFR, GLS, and GLSR than did controls (P < 0.05), but they had values of these markers that were similar to those of patients with CAD (P > 0.05) after adjustment for atherosclerotic risk factors: (PWVc [m/s], 10.4 ± 1.8 vs 8.6 ± 1.5 vs 10.3 ± 2, respectively; CFR, 2.4 ± 0.1 vs 3.4 ± 0.6 vs 2.6 ± 0.6, respectively; GLS [%], -16.2 ± 4 vs -21.9 ± 1.6 vs -16.6 ± 4.5, respectively; GLSR [L/sec], -0.85 ± 0.2 vs -1.2 ± 0.12 vs -0.9 ± 0.4, respectively; MDA [nM/L], 1.68 vs 1.76 vs 1.01, respectively; IL-6 [pg/mL], 2.26 vs 2.2 vs 1.7, respectively; P < 0.05 for all comparisons). PASI was related to IMT (r = 0.67; P < 0.01). Decreased GLS was associated with increased MDA, IL-6, PWVc, CAI, and reduced CFR (P < 0.05).

CONCLUSIONS

Psoriasis and CAD present similar vascular and LV myocardial dysfunction, possibly because of similar underlying inflammatory and oxidative stress processes. Vascular dysfunction in psoriasis is linked to abnormal LV myocardial deformation.

Evaluation of longitudinal myocardial deformation by 2-dimensional speckle-tracking echocardiography in heart transplant recipients: relation to coronary allograft vasculopathy

BACKGROUND

Coronary allograft vasculopathy (CAV) in heart transplant (HTx) recipients is characterized by diffuse affection of epicardial and intramyocardial coronary vessels. Despite significant CAV and anticipated affected myocardial function, left ventricular ejection fraction (LVEF) is often within the normal range, indicating the need of more sophisticated non-invasive methods to detect impaired myocardial function caused by CAV. Global longitudinal strain (GLS) represents a new echocardiographic measurement of systolic myocardial deformation. The aim of the study was to evaluate the relation between GLS measured by 2-dimensional speckle-tracking echocardiography and CAV in HTx patients.

METHODS

The study included 178 HTx patients and 20 healthy, age-matched individuals. All patients had an extensive echocardiographic evaluation and coronary angiography assessing CAV. CAV was classified according to International Society of Heart and Lung Transplantation classification (CAV0-3).

RESULTS

CAV was seen in 38.8% of patients. Compared with controls (-20.6% ± 1.4%), GLS was significantly reduced according to the degree of CAV (CAV0, -16.7% ± 2.4%; CAV1, -15.2% ± 2.9%; CAV2-3, -14.0% ± 3.8%; controls, -20.6% ±1.4%; pTREND < 0.0001). In addition, we found decreasing peak systolic mitral annular velocities (pTREND = 0.0040), tissue-tracking values (pTREND = 0.0002), and LVEF according to CAV class (CAV0, 65.3% ± 5.4%; CAV2-3, 56.9% ± 11.7%; pTREND < 0.0001). The HTx population showed significant restrictive physiology compared with the control population, but no significant correlation was seen between CAV class and traditional diastolic parameters such as E/A ratio (pTREND = 0.38) or E-deceleration time (pTREND = 0.14).

CONCLUSIONS

In contrast to LVEF and conventional pulsed mitral Doppler flow parameters used in the CAV classification, GLS relates to the presence and degree of CAV. The present results suggest GLS as a new method to be included in the monitoring of graft function in relation to CAV.

High prevalence of exercise-induced heart failure with normal ejection fraction in post-heart transplant patients

AIM

Post-heart transplant patients are at increased risk of diastolic dysfunction. The aim of this study was to assess the prevalence of isolated only exercise-induced heart failure with normal ejection fraction (HFNEF) in heart transplant recipients.

METHODS AND RESULTS

To determine pulmonary capillary wedge pressure (PCWP) at rest and during exercise, 81 patients after orthotopic heart transplantation with normal left ventricular ejection fraction (LVEF) underwent exercise right heart catheterization with simultaneous exercise echocardiography. Based on PCWP values, the patients were divided into three groups. Twenty-one patients had no evidence of HFNEF (PCWP at rest < 15 mmHg, maximal PCWP during exercise < 25 mmHg, prevalence 26%). Forty-seven subjects were found to have only exercise-induced HFNEF (PCWP at rest < 15 mmHg, maximal PCWP during exercise ≥ 25 mmHg, prevalence 58%). Thirteen patients had HFNEF already at rest (PCWP ≥ 15 mmHg at rest, prevalence 16%). Of the noninvasive parameters obtained at rest, multivariate regression analysis identified LV mass index adjusted for allograft age to be an independent predictor of exercise-induced HFNEF.

CONCLUSIONS

In heart transplant recipients with normal LVEF, there is a high prevalence of exercise-induced HFNEF. LV mass index adjusted for allograft age is predictive of exercise-induced HFNEF.