Ten-year experience with the Medtronic Hall valvular prosthesis. A study of 1,104 patients

The Medtronic Hall valvular prosthesis was introduced in 1977 and was used for the first time in Oslo in June of that year. We report here our 10-year experience with this prosthesis, based on studies of all 1,104 consecutive patients who were operated on from June 1977 to August 1987. There were 816 aortic (AVR), 187 mitral (MVR), and 101 combined mitral and aortic (double, DVR) valve replacements. Cumulative follow-up was 5,061 patient-years, with a mean follow-up of 4.6 years. Early mortality was 3.8% after AVR, 7.5% after MVR, and 10.0% after DVR. The probability of surviving 10 years after AVR was 72%; after MVR, 56%; and after DVR, 60%. Early and late survival reflected the patient's preoperative status and nonvalvular cardiac disease. Thromboembolism occurred at linearized rates of 1.3%, 1.3%, and 1.8%/yr after AVR, MVR, and DVR, respectively. There were five cases of valvular thrombosis, none fatal, resulting in a linearized rate of 0.1%, 0.1%, and 0.2%/yr after AVR, MVR, and DVR, respectively. There were no instances of structural failure. Morbidity from anticoagulant-related hemorrhage was 0.7%/yr, with seven fatal events, all of cerebral origin. The long-term experience with the Medtronic Hall valve indicates that, in addition to its previously demonstrated excellent hemodynamic performance, there are low risks of thromboembolism and thrombosis and no instances of primary structural failure.