The occurrence of postoperative pulmonary homograft stenosis in adult patients undergoing the Ross procedure.

BACKGROUND AND AIM OF THE STUDY: The Ross procedure employs an autologous pulmonary valve to replace the aortic valve, but requires pulmonary homograft replacement. Concerns regarding long-term homograft function may limit the adoption of this technique. Herein, the incidence of, and factors leading to, stenosis of the homograft were examined. METHODS: Data were collected from 131 patients (32 females, 99 males) who underwent a Ross procedure between July 1994 and December 2003. Complete follow up data were collected from 113 of 125 (90.4%) living patients. Donor valve information, including storage time, was supplied by the graft manufacturers. Data were analyzed using chi-square tests, t-test and logistic regression. RESULTS: The mean patient follow up was 703 +/- 574 days (median 599 days; range: 2 to 2,408 days). Echocardiographic stenosis had occurred in 14 patients (12.4%). Four patients (3.2%) required homograft replacement, and two required balloon valvuloplasty. There was no significant difference in graft vendor, recipient, donor age or blood type match between stenotic and non-stenotic recipients. Donor valve size was appropriate for the recipients, and greater than predicted by recipient body surface area (BSA). Donor valves that developed stenosis had a shorter storage time after processing (160 +/- 100 versus 249 +/- 223 days; p = 0.03). Male donor valves became stenotic in 9.9% (7/71) of male recipients, but in none of 20 females. Female donor valves became stenotic in 27.3% (3/11) of male recipients, and in 28.6% (2/7) females. Logistic regression showed donor gender to be a significant predictor for stenosis (p = 0.007; odds ratio 14.1 for female/male donors; 95% CI 2.1-96.4). CONCLUSION: Donor valves which developed stenosis had a shorter mean cryopreservation time than those that did not develop stenosis. In addition, female donor homografts appeared to develop stenosis at a greater rate, independent of patient age, graft size to BSA match, and blood type.