Mid-term experience with the Hancock porcine-valved Dacron conduit for right ventricular outflow tract reconstruction

Abstract

Surgical reconstruction of the right ventricular outflow tract (RVOT) often requires implantation of a valved conduit. A single-centre 10-year experience with the Hancock porcine-valved Dacron conduit was retrospectively assessed. The records of 63 patients who underwent RVOT reconstruction with Hancock conduit implantation between August 2000 and July 2010 were retrospectively reviewed. The median age was 13 years (range, 4 months to 64 years) and the median weight 44 kg (range, 6.5-75 kg). Fifty-one patients (83%) had previous cardiac surgery, and conduit replacement was performed in 31 patients (49%). Patient and conduit survivals with respect to factors precipitating conduit degeneration were analysed. Conduit failure was defined as severe conduit regurgitation or stenosis with a main pulmonary artery systolic gradient over 60 mmHg. Early mortality was 4.8% and not related to conduit failure. Follow-up was complete with a mean duration of 3.5 ± 2.6 years. Patient survival after conduit implantation was 93 [95% confidence interval (CI), 87-100], 90 (95% CI, 81-100) and 85% (95% CI, 74-98) after 1, 3 and 5 years, respectively. Conduit failure occurred in six patients after a median of 5.6 years (range, 2.7-9.0 years). Freedom from conduit failure was 100, 96 (95% CI, 89-100) and 83% (95% CI, 62-100%) after 1, 3 and 5 years, respectively. Mean systolic gradient over the stenotic conduit valve was 87 ± 11 mmHg. Neither RVOT-aneurysm formation nor distal conduit stenosis occurred. Univariate analysis revealed younger age and absent pulmonary valve syndrome as risk factors for conduit failure (P = 0.01 and P < 0.01). Stepwise logistic regression identified higher white blood cell count at postoperative day 8 as a significant risk factor for conduit failure (odds ratio, 0.7; 95% CI, 0.52-0.89; P < 0.01). The Hancock conduit is a valuable option for pulmonary valve replacement. It is not associated with RVOT-aneurysm formation or distal conduit stenosis. A persisting perioperative inflammatory reaction may be a predictor for later conduit failure.