Bidirectional Glenn shunt in association with congenital heart repairs: The 1 1/2 ventricular repair

Background. The bidirectional Glenn shunt has been used to incorporate a smaller tripartite ventricle into the circulation and create pulsatile pulmonary artery flow. We reviewed our operative experience and assessed hemodynamics of the bidirectional Glenn shunt in 1 1/2 ventricular repair or in conjunction with other repairs of congenital heart defects. Methods. Between 1992 and 1998, 15 patients (mean age, 8.1 ± 7.9 years) had bidirectional Glenn shunt in association with repair of congenital heart defects. Eighty-seven percent had at least one previous operation. All patients had simultaneous or previous intracardiac repair and had bidirectional Glenn shunt to volume unload the small right ventricle (group A, n = 7), to unload the poorly functioning right ventricle (group B, n = 2), to redirect superior vena cava-pulmonary venous atrial connection to treat cyanosis (group C, n = 2), or to unload the pulmonary left ventricle for residual intracavitary hypertension in patients with L-transposition of the great arteries, ventricular septal defect, and pulmonary stenosis (group D, n = 4). Intraoperative hemodynamic assessment was done in 2 patients in group A by selective use of inflow occlusion and flow probes. Results. All patients survived. Four patients had successful, concurrent arrhythmia circuit cryoablation for Wolf-Parkinson-White syndrome (n = 1) or atrial reentry tachycardia (n = 3). Superior and inferior vena caval flow averaged 36% and 64% of cardiac output, respectively. Postoperative superior vena caval pressure (n = 13) was 13.7 ± 4.0 mm Hg with pulmonary arterial flow pattern contributed by the ventricle in systole (pulsatile) and the superior vena cava in diastole (laminar). Conclusions. The bidirectional Glenn shunt is an effective adjunct to congenital heart repair to treat pulmonary ventricular pressure-volume problems and anomalous superior vena caval to left atrial connections.