Warfarin versus dipyridamole-aspirin and pentoxifylline-aspirin for the prevention of prosthetic heart valve thromboembolism: a prospective randomized clinical trial

• Published in: Circulation (New York, N.Y.) N.Y.), 1985-11, Vol.72 (5), p.1059-1063
• Main Authors: MOK, C. K, BOEY, J, WANG, R, CHAN, T. K, CHEUNG, K. L, LEE, P. K, CHOW, J, NG, R. P, TSE, T. F
• Format: Article
• Language: English
• Subjects: Adult; Aspirin - therapeutic use; Biological and medical sciences; Blood. Blood coagulation. Reticuloendothelial system; Clinical Trials as Topic; Dipyridamole - therapeutic use; Drug Combinations; Female; Heart Valve Prosthesis; Humans; Male; Medical sciences; Middle Aged; Pentoxifylline - therapeutic use; Pharmacology. Drug treatments; Postoperative Complications - drug therapy; Postoperative Complications - prevention & control; Prospective Studies; Random Allocation; Theobromine - analogs & derivatives; Thromboembolism - drug therapy; Thromboembolism - prevention & control; Warfarin - therapeutic use
• ISSN: 0009-7322; 1524-4539
• DOI: 10.1161/01.CIR.72.5.1059

In a prospective, randomized, parallel study, two regimens of platelet-suppressant therapy (PST)--dipyridamole-aspirin and pentoxifylline-aspirin--were compared with standard oral anticoagulation with warfarin in the prevention of prosthetic heart valve thromboembolism. In the entire group of 254 patients followed for 395.6 patient-years, the thromboembolic rate was significantly less in the warfarin group (warfarin vs dipyridamole-aspirin, p less than .005; warfarin vs pentoxifylline-aspirin, p less than .05). Subgroup analysis disclosed that, in patients with isolated mitral valve replacement, warfarin was superior to both of the PSTs with respect to the prevention of thromboembolism (warfarin vs dipyridamole-aspirin, p = .005; warfarin vs pentoxifylline-aspirin, p less than .05). Furthermore, a significant number of our patients could not tolerate the antiplatelet agents. However, in the rare situation in which repeated significant bleeding occurs despite careful adjustment of the dosage of warfarin, PST may be an acceptable alternate method of thromboembolism prophylaxis.