Right ventricular outflow tract reconstruction with an allograft conduit

Background. Allograft Conduits are used for reconstruction of the right ventricular outflow tract in patients with congenital heart disease and in the pulmonary autograft procedure. A retrospective evaluation of our experience with the use of allograft conduits for reconstruction of the right ventricular outflow tract was conducted. Methods. Between August 1986 and March 1999, 316 allografts (246 pulmonary, 70 aortic) were implanted in 297 patients for reconstruction of the right ventricular outflow tract. Main diagnostic groups were aortic valve pathology (n = 112, 35%), tetralogy of Fallot (n = 71, 22%), and pulmonary atresia with ventricular septal defect (n = 46, 14%). Kaplan-Meier analyses were done for survival, valve-related reoperation, and valve-related events. In addition, Cox regression analysis was used for evaluation of potential risk factors. Results. Mean age at operation was 18 years (range, 7 days to 61 years). Mean follow-up was 4 years (range, 2 days to 12 years). Twelve patients (4%) died within 30 days after operation. Patient survival was 90% (95% confidence interval [CI], 86% to 94%) at 5 years and 88% (95% CI, 83% to 94%) at 8 years Twenty-four reoperations were required for allograft dysfunction in 23 patients; 21 allografts were replaced. Freedom from valve-related reoperation was 91% (95% CI, 86% to 95) at 5 years and 87% (95% CI, 81% to 93%)at 8 years. Twenty-nine valve-related events were reported (2 deaths, 24 reoperations, 2 balloon dilatations, and 1 endocarditis). Freedom from valve-related events was 90% (95% CI, 85% to 94%) at 5 years after implantation, and 84% (95% CI, 77% to 91%) at 8 years. Risk factors for accelerated allograft failure were extra-anatomic position of the allograft (p = 0.03; hazard ratio, 9.7) and the use of an aortic allograft (p = 0.02; hazard ratio, 2.4). Conclusions. Right ventricular outflow tract reconstruction with an allograft conduit has good medium-term results, although progression of allograft degeneration is noted. Aortic allografts should preferably not be used for reconstruction of the right ventricular outflow tract.