Relation between global longitudinal strain and acute rejection in pediatric patients within the first-year post heart transplant

Background

Acute rejection leading to graft dysfunction remains a major cause of morbidity and mortality. In adults, assessment of global longitudinal strain (GLS) using speckle tracking echocardiography (STE) has been used as an early marker for graft dysfunction. Studies evaluating GLS in a sizable pediatric transplant population are scarce.

Objectives

We sought to determine association between GLS and acute rejection within first-year post-transplantation in pediatric patients.

Methods

Patients 0 to 18 years old who received heart transplants (HT) at Cleveland Clinic Children's Hospital after April 2013 were identified. Clinical data was collected from pre-transplant evaluation and post-transplant surveillance endomyocardial biopsy (EMB) visit from time of transplantation to one-year post-transplantation. Left ventricular (LV) GLS was measured retrospectively using vendor independent software. Significant rejection was defined by escalation in immunosuppression therapy due to pathology or clinical diagnosis. Trends of GLS were compared between patients with (Group 1) and without (Group 2) rejection, controlled for age. At the visit of rejection diagnosis, GLS rejection measurements were compared to the range of “normal”, non-rejection measurements.

Results

Twenty-seven patients met inclusion criteria. Eight patients (29.6 %) had at least one clinically significant rejection episode. There was no significant difference in GLS at the first endomyocardial biopsy visit between groups. At last biopsy visit, subjects with rejection had significantly worse GLS (p ≤ 0.001). In a mixed effect model, average global, 3-chamber, and 4-chamber systolic strain had significant interaction of group and time (p = 0.016, 0.033, 0.003, respectively). Systolic strain in those views significantly worsened over time in rejection group while remaining stable in non-rejection group. GLS of subjects with rejection were worse and out of the range of “normal” by the time of the third EMB visit.

Conclusions

There was a trend toward worse GLS in those who developed acute rejection within first year post-transplant compared to those without rejection.