Reoperation for obstructed pulmonary ventricle-pulmonary artery conduits. Early and late results

Obstruction of pulmonary ventricle-pulmonary artery conduits can result from neointimal peel formation or valvular degeneration and calcification. To determine the risks and outcome of reoperation, we reviewed the records of 100 consecutive patients who had replacement of severely stenotic pulmonary ventricle-pulmonary artery conduits. At reoperation, the 70 male and 30 female patients had a mean age of 13.3 +/- 4.8 years. During operation, 37 homografts, 62 Dacron grafts with integral xenograft valves, and one nonvalved conduit were replaced with valved (80) or nonvalved (17) prostheses. The mean transconduit pressure gradient decreased from 81 +/- 26 mm Hg preoperatively to 7 +/- 8 mm Hg postoperatively (p less than 0.01). Concomitant cardiac valve replacement was performed in seven patients, and residual ventricular septal defect closure was accomplished in 28. Operative mortality (less than 30 days) was 7%, but there were no deaths among the 47 patients who had no associated defects. At 3 and 5 years postoperatively, probability of survival among patients dismissed from the hospital was 94% +/- 3% and 86% +/- 6%, respectively. In our experience, risk of reoperation for conduit obstruction alone is low, so that the effect of graft failure on overall survival is minimized.