AORTIC-VALVE REPLACEMENT WITH CRYOPRESERVED PULMONARY ALLOGRAFTS - 5 YEARS FOLLOW-UP

Excellent clinical results with pulmonary autografts and experimental evidence that pulmonary valves can withstand the higher stress in the systemic circulation led us to use the cryopreserved pulmonary allograft for aortic valve replacement. From September 1988 until March 1993, 126 consecutive patients (61 +/- 10 years; 74 men and 52 women) underwent aortic valve replacement with a cryopreserved pulmonary allograft. All allografts were inserted freehand in the subcoronary position. There were four in-hospital deaths (3.2%), and 1 patient had severe valvular incompetence immediately postoperatively, requiring reoperation after 4 weeks. One hundred twenty-one patients were followed up in 3- to 6-month intervals for 25.3 +/- 16.3 months (range, 6 to 66 months), and valve performance was assessed routinely by means of color-flow Doppler echocardiography. Nine patients (7.1%) died during follow-up. Two patients died of multiple septic emboli during bacterial endocarditis, and 1 patient died of a massive stroke. The other 6 patients died of myocardial infarction (4), respiratory insufficiency due to chronic obstructive lung disease (1), and carcinoma (1). Ninety-four patients (78%) had absent or trivial aortic valve regurgitation. Valvular incompetence class II was present in 3 patients (2.5%), whereas 5 others (4%) demonstrated class II to III. Severe aortic regurgitation (class III or IV) could be detected in 10 patients (8.3%). All underwent reoperation and replacement of the valve with a prosthetic device. Bacterial endocarditis caused graft incompetence in 3 patients, valve degeneration was detected in another 3, and technical mistakes at valve implantation caused valve failure in the other 4. We assume that a mismatch in size between the allograft and the aortic annulus could have led to dilation of the allograft valve ring and consequently to central valvular incompetence in the patients without cusp degeneration. Cryopreserved pulmonary allografts achieve acceptable intermediate-term results, which can be improved if initial technical problems can be avoided. Disturbingly, the incidence of endocarditis in our series was higher than expected.