Determinants of right ventricular outflow tract conduit longevity: a multinational analysis.

Objective: The need for conduit replacement in the growing child remains a major problem after right ventricular outflow tract reconstruction. We compared two diverse surgical centers with considerable practice variation in Europe and the United States to identify modifiable risk factors that can increase conduit longevity.

Design: Retrospective analysis of 194 patients (56 Europe, 138 United States) who underwent primary right ventricular to pulmonary artery conduit placement between January 1987 and March 2003.

Patients: Diagnoses included tetralogy of Fallot with pulmonary atresia, truncus arteriosus, transposition of the great arteries with ventricular septal defect and pulmonary stenosis, and double-outlet right ventricle.

Results: Median age was 7.3 months (range 2 days-29.9 years). Types of conduits included aortic homografts (n = 111), pulmonary homografts (n = 48), Contegra conduits (Medtronic, Inc, Minneapolis, MN) (n = 23), and synthetic conduits (n = 12). Freedom from conduit failure at 5 years was 50% (58% Europe, 48% United States, P = NS). On multivariate analysis, smaller conduit diameter (hazard ratio [HR] 1.15, P < .001) and conduits other than pulmonary homografts (synthetic conduits [HR 3.17, P = .01], Contegra conduits [HR 2.80, P = .02], aortic homografts [HR 1.56, P = .05]) predicted shorter time to conduit failure. In addition, time to failure was longer for patients undergoing transcatheter intervention. Different surgical techniques in conduit preparation and insertion did not influence conduit longevity.

Conclusions: Analysis of the two diverse surgical centers showed that to increase conduit longevity, one should choose the largest possible conduit, use a pulmonary homograft, and consider children whose conduits develop obstruction as candidates for transcatheter intervention.