Twenty years' experience with the Medtronic Hall valve

Objective: To assess the performance of the Medtronic Hall valve (Medtronic , Inc, Minneapolis, Minn) in one institution over a 20-year period. Methods: Since 1979, Medtronic Hall valves have been used in 1766 procedure s (736 aortic, 796 mitral, and 234 double). Patients were followed up prosp ectively at 6- to 12-month intervals for a total of 12,688 follow-up years. Anticoagulation data (international normalized ratio) were recorded for al l patients (approximately 95,000 observations). Results: Linearized rates of valve-related late death for aortic, mitral, a nd double valve replacement were 0.8%/y, 0.9%/y, and 1.1%/y, respectively. Risk factors for late mortality were (relative risk) diabetes (1.9), decade of age (1.6), concomitant coronary artery bypass grafting (1.4), hypertens ion (1.3), non-sinus rhythm (1.3), large valve size(1.1), valve regurgitati on (1.3), and male sex (1.2). For aortic, mitral, and double valve replacem ent, linearized rates (percent per year) of adverse events were valve throm bosis 0.04, 0.03, and 0.0; all thromboembolism 2.3, 4.0, and 3.4; stroke 0. 6, 0.8, and 0.6; major hemorrhage 1.2, 1.4, and 1.6; and prosthetic endocar ditis 0.4, 0.4, and 0.7. Risk factors for thromboembolism were (relative ri sk) mitral valve replacement (1.9), diabetes (1.8), hypertension (1.5), and history of embolism (1.4). Conclusion: At 20 years the Medtronic Hall valve demonstrates excellent dur ability, good hemodynamic performance, and very low thrombogenicity, with a valve thrombosis rate lower than those reported for bileaflet designs. Wit h this prosthesis, both survival and thromboembolic events are predominantl y determined by patient risk factors.