Acute myocardial infarction in young Japanese adults.

BACKGROUND The prevalence and clinical manifestations of acute myocardial infarction (AMI) in young patients in Japan have not been fully investigated. METHODS AND RESULTS In the present study, 1651 AMI patients were enrolled in the AMI-Kyoto Multi-Center Risk Study between January 2000 and June 2004. Of these, the clinical background, risk factors, angiographic findings, acute results of primary percutaneous coronary intervention (PCI) and in-hospital outcomes for 27 young patients <40 (young group), and 338 non-young patients 60<or=, <70 years old (non-young group) were retrospectively compared. The young AMI patients were all male. Current smoking, hypercholesterolemia and family history were the most common risk factors in young patients, while hypertension and diabetes mellitus were more prevalent in non-young patients. Young patients had a higher prevalence of single-vessel disease and a lesser incidence of left circumflex coronary artery as a culprit lesion. The young group had high acquisition rates of Thrombolysis In Myocardial Infarction 3 flow just after primary PCI (95.8%) and no in-hospital deaths, which was not significantly different from the non-young group. CONCLUSIONS These results suggest that young AMI patients have different clinical characteristics from those in non-young AMI patients, and acute results of primary PCI and in-hospital prognosis in young AMI patients are comparable to those in non-young AMI patients in Japan.