Compared fate of small-diameter Contegras® and homografts in the pulmonary position

Abstract

This study analyzes whether small-diameter Contegras behave in the same way as small-diameter homografts, when implanted for the first time in pulmonary position. Small-diameter conduits include 12 and 14 mm Contegras and 8-14 mm homografts. Graft dysfunction is defined as right ventricular outflow tract obstruction with peak echo-Doppler gradient>40 mmHg, or grade III/IV graft regurgitation. Graft failure is defined as need for conduit replacement or need for catheter or surgical reintervention. Thirty-eight patients who received small Contegras (n=25) and small homografts (n=13) from October 2002 to end December 2006 were studied. The most frequent indication was pulmonary atresia and ventricular septal defect (n=20; 10 associated with major aorto-pulmonary collateral arteries), followed by truncus arteriosus (n=12). Most patients' characteristics were comparable except that recipients of homografts were smaller (p for body area=0.014). Survival, freedom from graft dysfunction, failure and explantation were estimated by the Kaplan-Meier method. The log-rank test was used to compare outcomes. There were three early and four late deaths. No death was graft related. Survival was 80+/-8.2% for patients with Contegras and 77+/-11.7% for those with allografts: p=0.82. Mean follow-up duration is 22+/-16 months. Freedom from dysfunction for Contegras conduits decreased in the first 6 months and stabilized at 58+/-11% from month 14. For homografts it decreased only 1 year after implantation, down to 35+/-19.7% from month 31: p=0.61. Freedom from Contegras failure diminished the first 16 months to level out at 57+/-13%. No homograft failed the first 2 years. With a p-value of 0.14, homografts tended to fail less frequently. Five grafts were explanted. Freedom from explantation was similar (p=0.98): 90+/-6.7% for Contegras and 75+/-21.6% for homografts at year 3. In the first 4 years after pulmonary implantation of small-diameter Contegras and homografts, the fate of both conduits was statistically similar, in spite of different behavior. As Contegras is 'off-the-shelf' available, it constitutes a sound alternative to homograft for right ventricular outflow tract reconstruction in neonates and infants.