Cryopreserved homograft valves in the pulmonary position: risk analysis for intermediate-term failure

Abstract

Objective: The purpose of this study was to examine the durability of cryopreserved homografts used to replace the "pulmonary" valve and to identify factors associated with their late deterioration.

Methods: We reviewed our entire experience (1985-1997) with 331 survivors in whom cryopreserved homograft valves (pulmonary, n = 304; aortic, n = 27) were used to reconstruct the pulmonary outflow tract. Median age was 14 years (range, 2 days-62 years). Operations included Ross operation (n = 259), tetralogy of Fallot (n = 41), truncus arteriosus (n = 14), Rastelli operation (n = 11), and others (n = 6). Median follow-up was 3.8 years (range, 0.2-11.2 years); late echographic follow-up was complete for 97% of patients. Homograft failure was defined as the need for explantation and valve-related death; homograft dysfunction was defined as a pulmonary insufficiency grade 3/4 or greater and a transvalvular gradient of 40 mm Hg or greater.

Results: Homograft failure occurred in 9% (30 of 331 patients; Kaplan-Meier); freedom from failure was 82% +/- 4% at 8 years. Homograft dysfunction occurred in 12% (39 of 331 patients), although freedom from dysfunction was 76% +/- 4% at 8 years. For aortic homografts, this was 56% +/- 11%, compared to 80% +/- 4% for pulmonary homografts (P =.003). For patients aged less than 3 years (n = 38), this was 51% +/- 12%, compared with 87% +/- 4% for older patients (P =.0001). By multivariable analysis, younger age of homograft donors, non-Ross operation, and later year of operation were associated with homograft failure; younger age of homograft donors, later year of operation, and use of an aortic homograft were associated with homograft dysfunction.

Conclusions: Homograft valves function satisfactorily in the pulmonary position at mid-term follow-up. The pulmonary homograft valve appears to be more durable than the aortic homograft valve in the pulmonary position.