Bleeding, clotting, and functional disability following Beall prosthetic mitral valve replacement.

Abstract

The incidence of fatal and nonfatal thromboemboli and bleeding episodes was compared in 53 patients who received sodium warfarin and in 17 successive patients who received no sodium warfarin after Beall mitral valve replacement. Actuarial curves showed that by 12 months postoperatively patients not receiving sodium warfarin had a greater incidence of emboli (P less than 0.01). This significant difference remained when the combined incidence of emboli and hemorrhage was considered (P less than 0.05). Deaths due to emboli or hemorrhage, however, were not statistically different in the two groups. The quality of control of prothrombin times (percent of prothrombin times two to two and a half times control) did not significantly influence the incidence of ebmoli although the numbers were small. However, fatal and nonfatal hemorrhagic episodes which did occur were almost invariably associated with prothrombin times greater than three to eight times control. Results of pre- and post-operative graded treadmill exercise tests in 39 patients receiving a Beall mitral valve replacement showed significant postoperative improvement in exercise tolerance. Nevertheless, the patients' postoperative working capacity was only 55% to 57% of that of age- and sex-matched sedentary controls. The present study supports the use of sodium warfarin therapy and strict anticoagulation control in Beall mitral valve replacement patients. It also documents a significant residual impairment in physical working capacity.