Clinical results of Hancock II versus Hancock Standard at long-term follow-up

Objective We performed a multi-institutional study to compare the long-term structural valve deterioration of isolated Hancock Standard versus Hancock II bioprostheses. Methods From 1983 to 2002, 714 Hancock Standard and 1293 Hancock II bioprostheses were implanted at hospitals of the Venetian territory (Padova, Treviso, and Venice). Follow-up on January 1, 2003, included 14,749 patient-years with a median of 12 years and was 96% complete: 115 Hancock Standard and 53 Hancock II bioprostheses were at risk at 15 years. The 2 series were nonconcomitant, and many covariates differed (Table 1). Survival was analyzed with Cox analysis, and durability was analyzed with Weibull analysis. Balancing analysis with the logistic propensity score model was performed. Results Perioperative mortality was 6% in Hancock II and 12% in Hancock Standard operations. The overall unadjusted 15-year survival was identical (39.7% ± 2.3% vs 39.9% ± 2.4%, respectively), but age-adjusted survival at 15 years was 46% versus 25% ( P Conclusion After balancing risk factors and calibrating age effects, Hancock II propensity-matched bioprostheses showed similar survival but definitely increased durability.