Left ventricular systolic strain of the cardiac allograft evaluated with three-dimensional speckle tracking echocardiography

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.

Global area strain is a sensitive marker of subendocardial damage in adults after optimal repair of aortic coarctation: three-dimensional speckle-tracking echocardiography data

Aortic coarctation (CoA) in adults is associated with reduced survival. Despite successful repair, some unfavorable changes in the left ventricular (LV) myocardial function are reported. Three-dimensional speckle-tracking imaging (3D-STE) is a novel method that allows to assess regional myocardial function in all directions simultaneously and to calculate global area strain which integrates longitudinal and circumferential deformation. The aim of our study was to assess whether 3-D STE provides any new characteristics of LV deformation in patients with optimal CoA repair. Adults after CoA correction underwent transthoracic echocardiographic examinations. Patients with significant concomitant lesions were ruled out. Global longitudinal strain (GLS), global circumferential strain (GCS), global area strain (GAS), and global radial strain (GRS) were assessed using 3D-STE (Echopac Software, GE). The data were compared with those obtained from healthy subjects. 26 adults (9F/17M; mean age 24.4 years) with repaired CoA were studied. Despite preserved LVEFs, patients with repaired CoA had decreased GAS compared with controls (−28.8 vs. −31.7 %; p = 0.007). No differences between patients and healthy subjects in terms of GLS, GCS and GRS were observed. We found a significant correlation between mean blood pressure and GAS (R = 0.39; p < 0.05). No significant influence of age at repair, CoA correction method or LV mass on three-dimensional deformation was observed. Summarizing, global area strain derived from 3D-STE may be a sensitive indicator of subclinical LV dysfunction in patients after optimal repair of CoA. Mean blood pressure, but not age at correction seems to determine LV deformation.