Changes in Longitudinal Myocardial Deformation during Acute Cardiac Rejection: The Clinical Role of Two-Dimensional Speckle-Tracking Echocardiography

Abstract

Diagnosing and monitoring acute cellular rejection (ACR) is a major objective in the surveillance of heart-transplanted patients. The aim of this study was to evaluate the value of global longitudinal strain (GLS), measured by two-dimensional speckle-tracking echocardiography, as a noninvasive tool for graft function monitoring in relation to ACR. The study population consisted of all heart-transplanted patients who underwent biopsy and corresponding echocardiography at one institution from 2011 to 2013 (n=64). ACR was classified according to the International Society of Heart and Lung Transplantation (0R-3R). Changes in graft function were serially evaluated before, during, and in the resolving period after ACR. No sign of rejection was seen in 268 biopsies (52.7%), minimal rejection (1R) in 202 biopsies (39.7%), and moderate rejection (2R) in 39 biopsies (7.7%); no patients had severe (3R) rejection. A significant difference in GLS was observed comparing the groups with 0R (-15.5%; 95% confidence interval, -16.2% to -14.2%), 1R (-15.3%; 95% confidence interval, -16.0% to -14.6%), and 2R (-13.8%; 95% confidence interval, -14.6% to -12.9%) rejection (P<.0001). GLS remained significantly reduced in the 2R group despite the exclusion of patients with impaired systolic function (ejection fraction < 50%), allograft vasculopathy, and late rejection (>2 years) after transplantation. In the serial assessment, GLS was decreasing significantly at the time of moderate 2R rejection and improved significantly in the resolving period. The traditional diastolic Doppler parameters, E-wave deceleration time and isovolumetric relaxation time, were unaffected by rejections, whereas the E/A and E/e' ratios were significantly higher in the 2R group (P=.004 and P=.01) compared with the 0R and 1R groups. GLS is significantly reduced during moderate (2R) ACR and improves significantly in the resolving period. The present results provide encouraging evidence to consider the routine use of GLS as a marker of graft function involvement during ACR.