Diastolic Biventricular Impairment at Long-term Follow-up After Atrial Switch Operation for Complete Transposition of the Great Arteries: An Exercise Tissue Doppler Echocardiography Study

Abstract

The aim of this study was to investigate regional myocardial function after atrial switch operation for transposition of the great arteries (TGA) using tissue Doppler echocardiography with strain rate (SR) imaging. In all, 24 patients with TGA aged 12 to 33 years and 10 control subjects underwent tissue Doppler echocardiography/SR imaging at rest and during bicycle exercise at 1 and 2 W/kg. Longitudinal function was quantified by strain, SR, and peak velocities measured in the free wall of the systemic ventricle, in septum and in the lateral wall of the subpulmonary ventricle. In patients with TGA, both ventricles showed reduced peak systolic SR values at rest. The increase in peak early diastolic velocity with exercise was reduced in the systemic ventricle (-47 +/- 23 mm/s at rest to -73 +/- 35 mm/s at 2 W/kg, P < .05) and absent in the subpulmonary ventricle (-78 +/- 38 mm/s at rest to -75 +/- 19 mm/s at 2 W/kg) of patients with TGA. Exercise tissue Doppler echocardiography/SR imaging identified severely reduced relaxation reserve of both ventricles as typical feature of myocardial dysfunction after atrial repair for TGA.