Long-term survival and complications in patients with mechanical aortic valves without anticoagulation. A follow-up study from 1 to 15 years.

In aortic valve replacement most centres prefer to use a mechanical valve for younger patients without special bleeding risks and treat the patient with lifelong anticoagulation. However, a few patients do not receive anticoagulation at all or have this withdrawn after some time. We examined the prognosis of 43 patients, 37 men and 6 women (mean age 52 years), who were treated with anticoagulation for approximately only 1 year (mean 13 months; range 4-35 months) after isolated aortic valve replacement with a mechanical valve. The mean follow-up period was 7 years and 3 months (1.5 months to 15 years and 10 months). After 5 and 10 years, 70% and 59%, respectively, were free of thromboembolic events, 65% and 55%, respectively, were free of valve-related events, and 87% and 83%, respectively, had survived. These figures correspond to linearized rates of thromboembolic events of 5.2%/pt-yr, valve-related events of 6.2%/pt-yr and death of 2.9%/pt-yr. We conclude that the best postoperative treatment in isolated aortic valve replacement with a mechanical valve is lifelong anticoagulation.