Pulmonary autograft versus aortic homograft for aortic valve replacement: Interim results from a prospective randomized trial - Discussion

Background and aim of the study: Although pulmonary autografts offer advantages over aortic homografts, they may also carry additional risks. We reviewed the interim results of a prospective randomized trial of autograft versus homograft aortic valve replacement (AVR) to determine if the greater complexity of the autograft insertion is justified, particularly with regard to time-related hemodynamic function. Methods: A total of 182 patients (82% male, 18% female; mean age 37.2 +/- 14.3 years; range: 2-64 years) with isolated aortic valve disease were randomized to pulmonary autograft (group A, n = 97) or aortic homograft (group H, n = 85); 42% had previous aortic valve surgery and 19% had native or prosthetic valve endocarditis. Follow up included annual outpatient visits and echocardiography. Results: Autograft AVR required longer cross-clamp (41%) and bypass (43%) times, but did not result in significantly more bleeding, longer recovery or more complications. One 30-day death occurred in group A (1%), and three deaths in group H (4%). Median follow up was 33.9 months (range: 1-61 months). There was one late death in each group, three reoperations in group A (all for pulmonary homografts), and three in group H (including two aortic homograft reoperations, both in children). There were no autograft reoperations. There were no other valve-related events. At 48 months, actuarial survival and reoperation-free survival rates were 97.8% and 94.2% in group A, and 95.3% and 87.7% in group H (p = NS). Echocardiography showed near-perfect function in all autografts, but early signs of subclinical dysfunction in many homografts. Conclusion: Both autograft and homograft AVR are safe and produce good intermediate-term results. Early homograft degeneration appears to favor autografts in children. The echocardiographic findings may translate into superior long-term autograft durability and hemodynamics.