급성 심근경색증 발생 위험인자와 경색관련동맥의 협착정도와의 연관성

Objectives: The most common cause of myocardial infarction is atherosclerotic lesion of epicardial coronary artery. But coronary blood flow can also be dampered by the arterial emboli, spasm. and this may result in myocardial infarction. To investigate the risk factors of myocardial infarction with normal coronary artery, a study was conducted. Methods: This study was made on 122patients, admitted at Yeungnam University Hospital as their first attack for acute myocardial infarction, from August 1992 to May 1994. The patients undertook angiography with thrombolytic therapy at the earliest possible time. These patients were classified into four groups: group 1-patients with less than 25% stenosis of infarct related artery(IRA); group 2-between 25-50% stenosis of IRA; group 3-between 51-75% stenosis of IRA; group 4-between 76-99% stenosis of IRA. Results: Among 122patients with myocardial infarction, the mean age was 55.4years old and the ratio of male to female was 3.5:1. Group 1patients had a significantly lower mean age(44.6years) than group 3patients(55.8years) and group 4patients (59.1years). Of fifteen patients in group 1, 12 patients developed acute myocardial infarction under 50years of age. In frequency of risk factors of coronary heart disease, 84 of 122cases(68.9%) were smokers. The number of smokers was higher in group 1 (86.7%) than group 3 (58.6%) and group 4 (64%). The frequency of angina prior to myocardial infarction was lower in group 1 (7%) than group 3 (45%) and group 4 (46%). The frequency of multivessel disease was lower in group 1 (13%) than group 3 (31%) and group 4 (50%). There was no significant difference in the frequency of the hypertension, diabetes, dyslipidemia, and obesity among the groups. Conclusion: Acute myocardial infarction with near normal infarct related artery developed at young age compared with those with significant infarct related artery stenosis. The number of smokers was higher and the frequency of previous angina history was lower in the same group.