Background: Autograft aortic root replacement is an established therapeutic option for young adults with aortic valve disease. Unfortunately, most series are small with a limited follow-up. Meta-analysis and microsimulation modeling were used to predict long-term outcome based on currently available midterm data.
Methods: We combined our center's experience with autograft aortic root replacement in 85 adult patients in a meta-analysis with reported results of three other hospitals. The outcomes of this meta-analysis were entered in a microsimulation model, calculating (event-free) life expectancy after autograft aortic root replacement.
Results: The pooled results comprised 380 patients with a total follow-up of 1,077 patient-years. Mean age was 37 years (range 16 to 68 years). Male/female ratio was 2.7. Operative mortality was 2.6% (n = 10); during follow-up 6 more patients died. Linearized annual risk estimates were 0.5% for thromboembolism, 0.3% for endocarditis, and 0.4% for nonstructural valve failure. Structural autograft failure requiring reoperation occurred in 5 patients, and a Weibull function was constructed accordingly. Using this information, the microsimulation model predicted age- and gender-specific mean, reoperation-free, and event-free life expectancy.
Conclusions: Based on current evidence the calculated average autograft-related reoperation-free life expectancy is 16 years. The combination of meta-analysis and microsimulation provides a promising and powerful tool for estimating long-term outcome after aortic valve replacement.