Early stage 2 palliation is crucial in patients with a right-ventricle-to-pulmonary-artery conduit

BACKGROUND: Improved survival after Norwood stage 1 palliation is giving more patients the opportunity to reach stage 2 palliation; thus, more patients are exposed to the risk of interstage death.

METHODS: A single-center review of patients who underwent stage 1 palliation from January 1998 to December 2007 (n = 58) was performed. Pulmonary blood flow was established either by a modified Blalock-Taussig-shunt (mBTS, n = 33) or a right ventricle-to-pulmonary artery conduit (RVPAC, n = 25).

RESULTS: Hospital, interstage, and 1-year survival was not significantly different between groups. However, Kaplan-Meier survival analysis reflected a significantly higher survival probability for RVPAC patients until the age of 120 days (RVAPC, 92% ± 5% [standard error of the mean]; 95% confidence interval, 82 to 100; mBTS, 63% ± 9%; 95% confidence interval, 48 to 82; p = 0.01). During a 1-year follow-up, all 11 nonsurvivors with mBTS died at an age younger than 120 days, including 2 patients with early stage 2 palliation. In contrast, besides 2 early deaths, all RVPAC patients (n = 5) showed later attrition at an age older than 120 days while awaiting stage 2 palliation. Interstage death occurred significantly later among RVPAC patients (RVPAC, 146 ± 60 days versus mBTS, 81 ± 23 days; p = 0.01). After stage 2 palliation, all patients with RVPAC survived, including 7 patients with surgery at an age younger than 120 days. All interstage and late deaths were related to compromising cardiac lesions with no statistical difference between groups.

CONCLUSIONS: After Norwood stage 1 palliation, survival was improved with RVPAC for the first 4 months. However, a loss of the favorable primary outcome was present by delaying stage 2 palliation beyond the age of 120 days. Progressive volume load as a result of conduit regurgitation may play a crucial role for later attrition. Residual lesions should be addressed early to preserve cardiac function.