Human tissue valves in aortic position - Determinants of reoperation and valve regurgitation

Background-Human tissue valves for aortic Valve replacement have a limited durability that is influenced by interrelated determinants. Hierarchical li near modeling was used to analyze the relation between these determinants o f durability and valve regurgitation measured by serial echocardiography, Methods and Results-In adult patients, 218 cryopreserved aortic allografts were implanted with the subcoronary (85) or the root replacement technique (133), and 81 patients had root replacement with a pulmonary autograft. Mea n follow-up was 4.2 years (SD 2.7; range, 0 to 10.5). Patient age, operator experience with subcoronary implantation, and allograft diameter were inde pendent predictors for reoperation. With repeated color Doppler echocardiog raphy, the severity of aortic regurgitation was assessed by the jet length method and the jet diameter ratio, Multilevel hierarchical linear modeling was used to estimate initial aortic regurgitation (intercept), its change o ver time (slope), and the effect of 11 potential determinants of durability on aortic regurgitation. With the jet length method, the intercept was 0.9 4 grade and the slope was 0.11 grade per year. With the jet diameter ratio, the intercept was 0.34 and the annual increase was 0.01. Subcoronary impla nted valves had more initial aortic regurgitation, but progression of aorti c valve regurgitation did not differ from root replacement. At midterm. fol low-up, recipient age <40 years was the only independent predictor of aorti c regurgitation. Conclusions-Subcoronary implantation has a learning curve, resulting in mor e initial aortic regurgitation and early reoperation compared with root rep lacement. In both techniques, progression of aortic regurgitation over time is small but accelerated in young adults.