[Reoperation for late postoperative right ventricular outflow tract obstruction]

Between February 1993 and July 2000, 18 patients with a mean age of 7.9 years underwent re-operation for critical stenosis of the right ventricular outflow tract. Their diagnoses of these patients included tetralogy of Fallot (n = 7), transposition of the great arteries (n = 6), truncus arteriosus communis (n = 3), and double outlet right ventricle with pulmonary stenosis (n = 2). The first operations were extracardiac conduit operations (n = 9), arterial switch operations (n = 6) and patch reconstruction of the right ventricular outflow tract (n = 3). At re-operation, the right ventricular outflow tract obstruction was released completely and reconstructed using a monocusp ventricular outflow patch (n = 14), valved pericardial roll (n = 2), or bovine pericardial patch sparing the native pulmonary valve annulus (n = 2). There were no early deaths, although one patient died of arrhythmia 2.6 years after re-operation. The pressure gradient across the right ventricular outflow tract, right ventricular systolic pressure, and right ventricle to systemic systolic pressure ratio were satisfactorily relieved (84.3 +/- 19.0 vs. 16.7 +/- 19.7 mmHg, 109.2 +/- 20.5 vs. 48.7 +/- 16.7 mmHg, 0.92 +/- 0.25 vs. 0.43 +/- 0.16; p < 0.001, p < 0.001, p < 0.001, respectively). The right ventricular end-diastolic volume index and right ventricular ejection fraction were also improved (166.3 +/- 85.2 vs. 105.6 +/- 28.8% of normal, 38.3 +/- 12.6 vs. 50.9 +/- 8.8%; p < 0.05, p < 0.005, respectively). Re-operation should be done before the development of marked right ventricular dysfunction, while it can still be performed at a low risk with satisfactory results.