Changes in longitudinal myocardial deformation during acute cardiac rejection: the clinical role of two-dimensional speckle-tracking echocardiography

Abstract

Background: 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.

Methods: 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.

Results: 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.

Conclusions: 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.

Keywords: Global longitudinal systolic function; Heart transplantation; Rejection; Speckle-tracking.