Biological versus mechanical aortic valve replacement in children

Aortic valve replacement in children remains challenging because of constraints imposed by available prosthetic devices. Potential risks of anticoagulation with mechanical valves and degeneration of other biological substitutes have kindled interest in the Ross procedure. This study outlines the evolution of our 27-year experience with prosthetic devices.

Ninety-nine patients who underwent aortic valve replacement (January 1973 through September 2000) were included in this study. Procedures included implantation of pulmonary autograft (PA) (n = 42), aortic homograft (AH) (n = 3), mechanical valves (MV) (n = 41), and xenograft tissue valves (XG) (n = 13).

The mean follow-up times were: 3.8+/-1.3 years for PA, 3.5+/-1.5 years for AH, 7.7+/-4.7 years for MV, and 8.4+/-4.8 years for XG. There were no significant differences in perioperative outcomes among the groups (p < or = 0.05) or early deaths (2 each in the MV, AH, and PA groups). The incidence of valve-related complications and reoperations was high in the MV (n = 5), XG (n = 7), and AH (n = 1) groups as compared with the PA group (n = 3, p < 0.01). Early and late mortality for the series was 8.6% (n = 8). Overall, the reoperation rate was 20.7% (n = 18): 15.2% (5 of 33) MV, 70% (7 of 10) XG, 50% (1 of 2) AH, and 11.9% (5 of 42) for PA. The actuarial survival rate was 87.8% and 100% at 10 years for MV and XG, and 95.2% and 6.6% at 7 years for PA and AH.

Aortic valve replacement in children can be performed with acceptable mortality and good long-term results. The Ross procedure, although more complicated, has the advantage of not requiring anticoagulation therapy, can be performed in all age groups, possesses inherent growth potential, and exhibits the most normal left ventricular outflow tract hemodynamics.