In Search of Coronary Thrombosis as the Cause of Myocardial Infarction: Unraveling a 20th-Century Mystery

For the greater part of the 20th century, the pathophysiology of acute myocardial infarction regarding whether thrombosis was either present or primary was debated until 1973 when pathologists and clinicians met and by consensus, finally decided that the data supported that transmural infarction (what we now refer to as ST elevation myocardial infarction or STEMI) was caused by thrombus in the vessel supplying the infarcted territory. As the data for this consensus came from pathological analysis, it took another 7 years until angiographic and interventional data in humans with acute presentations of transmural infarction convincingly indicated that thrombus was indeed responsible. Subsequently, in patients presenting with either syndromes of unstable angina or nontransmural (later called non-ST elevation) myocardial infarction, it was established through angiographic and other interventional approaches that thrombus formation was also causative in a substantial proportion of these patients. This article reviews the history and this search for causation of myocardial infarction that now has resulted in present therapies that have saved innumerable lives over the last 30 to 40 years.