Anti platelet agents for strokes and myocardial infarction: a critical appraisal of recent clinical trials.

Attempts at prevention of arterial thrombosis with platelet inhibitors have been the subject of a number of major trials in recent years. These trials were prompted by earlier observations that aspirin takers seemed to fare better after acute myocardial infarction and were further stimulated by the recent growth of knowledge about the role of vascular and platelet prostaglandins. The trials have sought to establish that aspirin (ASA), sulphinpyrazone and dipyridamole may prevent thrombosis in the form of recurrence of transient ischaemic attack (TIA) and stroke or reduce the recurrence rate and mortality after acute myocardial infarction. No single trial has provided conclusive evidence although there is a strong suggestion of some benefit from ASA. With further understanding of PG metabolism and the effects of inhibitors new approaches are likely to emerge in the near future.