RESUMO
BACKGROUND: The choice of a valve substitute in young adults requires a decision balancing the risks of long-term anticoagulation versus reoperation(s). This article analyzes the long-term risk and determinants of thromboembolic (TE) and bleeding (BLE) complications after mechanical aortic valve replacement (AVR). METHODS: From December 1963 to January 1974, 249 patients survived a mechanical AVR at our institution. Mean age was 41.8+/-12.4 years and 81% (n = 202) were male. Ball valves were implanted in 24% (n = 61) and disc valves in 76% (n = 188). Patients were anticoagulated with vitamin K antagonists and dipyridamole. A total of 4,855 patient-years was available for analysis. Mean follow-up was 19.5+/-9.4 years and was 100% complete. Analyses were performed with Kaplan-Meier and multivariable Cox regression methods. RESULTS: One hundred and two patients had one TE or BLE postoperative event and 58 patients had two postoperative events. Six patients had more than five postoperative events. Freedom from a first postoperative event was 74.8%+/-2.9%, 55.3%+/-3.5%, and 46.8%+/-4.0% at 10, 20, and 30 years, respectively. Freedom from a second postoperative event was 45.4%+/-5.4%, 29%+/-6.0%, and 23.2%+/-7.1% at 10, 20, and 30 years, respectively. Multivariate predictors for TE or BLE complications were ball valve (Odds Ratio (OR) = 2.9), postoperative endocarditis (OR = 2.2), and any surgery (OR = 2.2). The incidence of events was highest the first 5 postoperative years. CONCLUSIONS: The risk of adverse events is highest the first 5 postoperative years. Once an event has occurred, the risk for a second event is increased. The incidence and frequency of events is substantial and should be considered in the choice of a valve substitute.
