title: Thromboembolism in patients with prosthetic heart valves. An adequately controlled intense anticoagulant therapy and its influence on the occurrence of thromboembolism in relation to valve type.
abstract: This study was designed to evaluate the efficacy of carefully controlled treatment with oral anticoagulants in patients with different mechanical heart valve prostheses. One hundred eighty-one patients with various types of prosthetic valves (mitral 89, aortic 87, combined 5) received oral anticoagulation aiming at Thrombotest (TT) values between 5% and 12%. Median follow-up was 46 months; 80.8% of all TT determinations were below 12%. The thromboembolic rate was 0.25%/year in patients with aortic valve replacement (AVR) and 4.87%/year in patients with mitral valve replacement (MVR). There was a strikingly lower incidence of thromboembolism with newer types of valves (Björk-Shiley convex-concave) in the mitral position under exactly the same intensity and stability of anticoagulant treatment. Clinically overt valve occlusion could be almost completely prevented (0.12%/year) in prostheses at both sites. Severe hemorrhage occurred at a rate of 1.71%/year and fatal bleeding at a rate of 0.37%/year. Our results indicate that carefully controlled anticoagulation is effective in the reduction of thromboembolic complications at a reasonable risk of bleeding.
mesh_terms: D015110:4-Hydroxycoumarins / Q000627:therapeutic use*; D000328:Adult; D001021:Aortic Valve / Q000601:surgery; D005260:Female; D005500:Follow-Up Studies; D006350:Heart Valve Prosthesis / Q000009:adverse effects*; D006801:Humans; D008297:Male; D008875:Middle Aged; D008943:Mitral Valve / Q000601:surgery; D010644:Phenprocoumon / Q000627:therapeutic use*; D011474:Prosthesis Design; D011517:Prothrombin Time; D012306:Risk; D013923:Thromboembolism / Q000209:etiology / Q000517:prevention & control*
chemical_list: D015110:4-Hydroxycoumarins; D010644:Phenprocoumon