Relationship of plasma anti-heparin activity and platelet survival time in coronary disease

Abstract

Platelet-endothelial interaction probably plays a role in the development of atherosclerotic vascular disease and its complications. Platelet survival time has been found to be shortened and plasma anti-heparin activity has been shown to be increased in patients with coronary atherosclerosis. Platelet survival (autologous labelling with 51Chromium) and plasma anti-heparin activity (heparin-thrombin clotting time of platelet poor plasma) were measured in 75 men with coronary artery disease. Platelet survival was shortened (< 3.3 days) in 60 men (80%) and averaged 2.6 ± 0.06 days (AVE t 1 2 ± SEM ; normal t 1 2 3.7 ± 0.03 days; N = 28; P < 0.001). Anti-heparin activity was abnormal (< 0.96) in 26 men (35%) and averaged 1.04 ± 0.02 (ratio patient to blank; seconds/seconds; normal ratio 1.10 ± 0.01; N = 25; P < 0.01). Platelet survival time correlated with anti-heparin activity (r = 0.68). Sulfinpyrazone (800 mg. daily) and indomethacin (100 mg. per day) increased platelet survival and decreased heparin neutralizing activity. Dipyridamole (100 mg. orally per day) in combination with aspirin (1,200 mg. per day) increased platelet survival and decreased anti-heparin activity, but aspirin alone had a comparatively weak effect on these tests. Results suggest that plasma heparin neutralizing activity correlates with platelet survival time in men with coronary artery disease. Sulfinpyrazone, indomethacin, and dipyridamole in combination with aspirin alter platelet survival and heparin neutralizing activity, but aspirin alone has a comparatively weaker effect.