Aortic valve replacement with cryopreserved pulmonary allograft.

Experimental as well as clinical data support the finding of using the pulmonary valve as a systemic semilunar valve. From January 1990 to December 1992, 89 patients received pulmonary cryopreserved allografts as aortic valve replacement. Sixteen subjects suffering from native or prosthetic valve endocarditis were included. Age ranged from 10 to 74 years. Sixty-five patients received isolated aortic valve replacement and 24 patients required additional surgical measures, such as coronary artery bypass graft, mitral valve reconstruction, replacement of the ascending aorta, supravalvular patch aortoplasty, ventricular septal defect closure, or myectomy. All operations were performed with normothermic bypass and cold cardioplegic arrest. Follow-up is maintained by visits to the outpatient clinic and echocardiographic assessment of the valve status every 3 months during the first year and every 6 months thereafter. There were four early and three late deaths. Four valves had to be removed: one intraoperatively and three 2, 4, and 24 months postoperatively. Echocardiographic assessment proved that gradients across the valve were low or absent. The majority of patients showed trivial or no aortic regurgitation during follow-up. No thromboembolic events have been observed and no new endocarditis occurred. Thus, event-free survival at 3 years is 87%. The results with pulmonary allografts have shown to be comparable to aortic allografts. Even in patients with acute native or prosthetic valve endocarditis, the use of cryopreserved pulmonary allografts has shown no adverse effects. We continue to implant cryopreserved pulmonary allografts in the aortic position. The long-term function of the valve, however, must be established, making continued evaluation of postoperative patients mandatory.