THROMBIN ACTIVATION AND LATE RESTENOSIS AFTER PERCUTANEOUS TRANSLUMINAL CORONARY ANGIOPLASTY

Background Mechanisms of restenosis after percutaneous transluminal co ronary angioplasty (PTCA) have not been defined yet. Experimental stud ies have shown that thrombin, by stimulating platelet growth factor se cretion and smooth muscle cell proliferation, can play a major role. M ethods and Results In 34 patients with single-vessel coronary disease undergoing PTCA, thrombin activity was evaluated through serial fibrin opeptide A (FPA) plasma determinations. Samples were performed before PTCA, immediately after and 24 hours, 72 hours, and 6 months later. Pa tients were grouped according to the development (group 1, n = 13) or nondevelopment (group 2, n = 21) of restenosis at a 6-month angiograph ic control. No difference in the two groups was found concerning basel ine FPA values. In patients in group 1, soon after PTCA higher FPA lev els (27.3 +/- 13.7 ng/ml) than those in group 2 (9.2 +/- 5.6 ng/ml; p < 0.05 vs pre-PTCA, and p < 0.01 between the two groups) were observed . No differences in FPA levels were detected at the other steps betwee n the two groups. Conclusion Our data suggest that thrombin plays a ro le in the process of restenosis after PTCA; acute FPA response to the procedure seems to have a predictive value.