Favorable effect of sulfinpyrazone on thromboembolism in patients with rheumatic heart disease.

Thromboembolism complicates the course of patients with rheumatic heart disease (mitral stenosis) and platelet survival time has been shown to be shortened in patients with a history of thromboembolism; sulfinpyrazone has been shown to increase platelet survival in these patients. A prospective, blinded trial of sulfinpyrazone therapy in patients with rheumatic heart disease has been completed. One hundred fiftyfour of 186 patients had shortened platelet survival (chromium-51 labeling of autologous platelets) on enrollment and were randomized to treatment with either sulfinpyrazone or placebo. Thirty-two patients with initially normal platelet survival were neither randomized nor treated. New thromboembolism occurred in 19 patients during 4 years of observation: two received sulfinpyrazone, 16 received placebo (X 2 = 12.75,p < 0.01) and one had normal initial platelet survival time. Sulfinpyrazone increased platelet survival time (control 2.5 ± 0.04 days [average ± SEMI]; normal half life 3.7 ± 0.03 days; 1 year 2.8 ± 0.04 days; n = 78) relative to placebo (control 2.6 ± 0.04 days; 1 year 2.5 ± 0.05 days; n = 76, p < 0.01). The results of this trial confirm earlier work suggesting that platelet survival time is frequently shortened in patients with rheumatic heart disease, and that sulfinpyrazone increases platelet survival. Sulfinpyrazone appears to decrease thromboembolism in patients with rheumatic mitral stenosis.