Comparison of Quantitative Echocardiography With Endomyocardial Biopsy to Define Myocardial Rejection in Pediatric Patients After Cardiac Transplantation

Abstract

Endomyocardial biopsy is the gold standard for determining rejection; however, no echocardiographic indexes have been widely accepted as indicators of rejection. The stress-velocity relation of corrected velocity of circumferential fiber shortening to wall stress is a preload independent index of contractility that incorporates afterload and has been shown to distinguish a decreased velocity caused by excess afterload from that caused by decreased contractility. Wall stress has not been previously reported as a determinant of rejection. We report a prospective double-blind study of pediatric cardiac transplant patients comparing biopsy and quantitative systolic echocardiographic data. Thirty-two pediatric patients underwent 67 biopsies. At the time of catheterization, an echocardiographic evaluation was performed. Standard measurements of systolic function were collected and left ventricular (LV) fractional shortening, LV volume, LV mass, velocity of circumferential fiber shortening, and estimated end-systolic wall stress were calculated. In evaluating echocardiographic data of patients with and without biopsy-proven rejection, we were unable to identify any significant correlation between any systolic echocardiographic parameter and rejection. We conclude that: (1) the stress-velocity relation does not detect myocardial rejection; and (2) neither LV fractional shortening, LV volume, nor LV mass detect rejection; and (3) central venous pressure influence wall stress values significantly.