Primary thrombocythemia and myocardial infarction in a 26-year-old woman with normal coronary arteriogram.

Acute myocardial infarction occurred in a 26-year-old woman with normal coronary arteriogram and primary thrombocythemia (500,000 approximately 1,500,000/mm3). Hyperaggregability of platelets was also demonstrated by stimulation with adenosine diphosphate, collagen, and epinephrine administration. A stillbirth at the 8th month of gestation in her past history was referred to the complication of primary thrombocythemia, too. Since discharge, the patient has been on 750 mg of aspirin and then free of any thromboembolic symptoms and signs, even during pregnancy and labour.