[Platelet antiaggregants in the treatment of arterial thrombosis]

The paper contains a critical review of the major clinical controlled trials which have been carried out on the use of platelet anti-aggregating agents in the prophylactic treatment of arterial thrombosis. The drugs studied to date include aspirin, sulphinpyrazone, dipyridamole and ticlopidine. These drugs have been used in primary infarction prophylaxis and secondary prophylaxis of arterial thrombosis at a cardiac (reinfarction, instable angina, valvular prosthesis, aortocoronary bypass, coronary angioplasty), cerebral (TIA, ictus) and peripheral (obliterating arteriopathy, thromboendarterectomy, arteriovenous shunt) level. The most frequently studied end-points are non-fatal reinfarction, cardiovascular mortality (fatal reinfarction, sudden death, fatal ictus), non-fatal ictus, vascular re-occlusion after arterio-lesive surgery, and some clinico-radiographical parameters at a peripheral level. The best results, which are statistically significant, have been obtained in the prophylaxis of instable angina and re-occlusion following aortocoronary by-pass; results obtained in cerebrovascular disease and peripheral obliterating arteriopathy are less statistically significant but equally successful and worthy of attention, especially in the case of ticlopidine which showed a greater number of advantages than aspirin. Positive but statistically not reliable findings were reported regarding the secondary prophylaxis of reinfarction, whereas non-significant data were reported for secondary prophylaxis of reocclusion of coronary angioplasty, thromboendarterectomy and arterio-venous shunt, and for the primary prophylaxis of reinfarction. The Author confirms that the clinical trials carried out for the long-term prophylaxis of still asymptomatic subjects are the only way of evaluating the clinical efficacy of a platelet anti-aggregating agent; the results of these trials must however be carefully and critically assessed from a clinical and statistical point of view and at all events can only act as a guideline for the doctor; the latter continues to be solely responsible for the choice of the drug and he must be aware of possible collateral effects and the risk/benefit ratio as well as the personal characteristics of the patient.