Two-Dimensional and Doppler Echocardiographic Follow-up after the Arterial Switch Operation for Transposition of the Great Arteries

Abstract

An echocardiographic follow-up examination was performed in 20 children who underwent an arterial switch operation from November 1984 to October 1990. The age at the time of operation ranged from 1 to 54 days, the weight ranged from 2.5 to 4.5 kg body weight. The time interval from the day of operation and the examination ranged from 3 to 74 months. M-mode echocardiography showed hypokinetic left ventricular function in 6 patients (30%). Abnormal segmental left ventricular wall motions were found in 6/16 patients (37.5%). Doppler echocardiographic examination at the site of the pulmonary anastomosis revealed an instantaneous gradient less than 20 mmHg in 9 patients (45%), a gradient between 20 and 60 mmHg in 9 patients (45) and a gradient greater than 60 mmHg in two patients (10%). The location of the stenosis was just below the bifurcation in 17 patients (85%) and seemed to be related to stretching of the pulmonary trunk during the Lecompte maneuver. One patient (5%) had a supravalvular aortic stenosis with a gradient of 43 mmHg. Color-flow mapping revealed mild aortic regurgitation in 8 patients (40%) but moderate regurgitation in one patient (5%). Three patients (15%) showed mild mitral regurgitation, all of them also had hypokinetic left ventricular function.