Recently, the incidence of acute myocardial infarction increased with prolongation of life spans, improvements in food and life styles in Korea, But only few studies were reported after the newly developed diagnostic methods and treatment modalities were introduced. So, the study on left ventricular ejection fraction, findings in coronary angiography, uses of thrombolytic agents was needed.

A retrospective clinical study was done on 654 patients with acute myocardial infarction who had been admitted to Severance hospital from January 1985 to December 1991 within 30 days after the onset of symptoms. Coronary angiogram and radionuclide ventriculography was done as usual methods.

The mean age was 58.5 years, and the ratio of males to females was 3.3:1, The major risk factors were smoking, hypertension and diabetes mellitus in males. and hypertension, diabetes mellitus and obesity in females. Arrhythmias were found in 360 patients(56.4%). The most frequent arrhythmia was premature ventricular contraction. Sinus bradycardia and atrioventricular were more frequent in inferior infarction but sinus tachycardia, ventricular tachycardia were more frequent in anterior infarction. The peak serum CK and CK-MB levels were higher in patients of anterior infarction than in those of inferior and non-Q wave infarction. The left ventricalar ejection fractions were higher in the patients with non-Q wave infarction, inferior infarction than in the patients with anterior infarction. There was no difference in left ventricular ejection fraction between patients who received thrombolytic therapy and not treated patients. Coronary angiograms were performed in 362 patients and 184 patients (50.8%) had one-vessel disease. The short-term mortality rate was 15.1%. The most common cause of death was cardiogenic shock(60.6%). Poor prognosis was found in patients with a history of previous myocardial infarction, those over 60 years old, those with a complete heart block and those of the female sex. The short-term mortality was higher in anterior infarction than inferior infarction and short-term mortality was higher in Q wave infarction than non-Q wave infarction.

This study suggests that smoking was the most common risk factor but hypercholesterolemia and obesity were less significant. According to coronary angiogram, one-vessel disease was the most common, and the rate of insignificant reduction in luminal diameter was higher than western countries. The short-term mortality rate of acute myocardial infarction was higher than those of western countries. The cause of high mortality rate was considered due to delay in transportation of patients to hospital. The education about acute myocardial infarction should be done to public and transportation system must be improved.