Objective: To compare the function in aortic position of cryopreserved pulmonary homografts subjected to pulmonary hypertension with that of normal cryopreserved pulmonary homografts.
Methods: Pulmonary valves (52) were implanted in aortic position in different cardiothoracic centres. The valves were classified as follows: Group I-pulmonary hypertension (procured from recipients of heart/heart-lung transplantation, 31 valves), Group II-normal pulmonary pressure (procured from cadavers and multiorgan donors, 21 valves). Regular echocardiographic follow-up was obtained by the implanting centers. Significant echo changes were defined as insufficiency > 2+ and/or stenosis producing a delta P > 30 mm Hg.
Results: Pulmonary homografts showed the following significant echo changes: in the Pulmonary Hypertension Group, 7, 27 and 33% at 12, 24 and 36 months, respectively; in the normal PA Group 10, 37.5 and 80% at 12, 24 and 36 months, respectively. In both groups the most common echocardiographic alteration was homograft insufficiency rather than stenosis. Thus, pulmonary homografts subjected to long-term pulmonary hypertension have significantly less echo changes than normal pulmonary homografts, especially after 12 months (chi 2: P < 0.036).
Conclusions: These findings suggest that pulmonary valves subjected to pulmonary hypertension might be more appropriate than normal pulmonary homograft for aortic valve replacement, constituting a possible alternative in case of lack of aortic valve homografts. However, the failure of two out of five valves in the longer term must dictate caution while waiting further long-term results.