Significance of symptomatological diagnosis and treatment of angina pectoris developing into acute myocardial infarction.
Consecutive 200 patients with angina pectoris (AP) and 310 with acute myocardial infarction (AMI) were studied in order to elucidate the significance of symptoms and treatment of AP associated with AMI, and to evaluate the classification of unstable angina (UA) according to the American Heart Association (AHA). The AMI group consisted of 110 patients without preinfarction AP, 99 with UA and 101 with AP who did not meet the criteria of UA and were designated as non-UA (NUA) in this study, while the AP group consisted of 65 with UA and 135 with NUA. Among 19 patients who developed AMI during their hospitalization, 12 were UNA. Patients with NUA of both groups revealed various modes of anginal attacks. Eighteen patients of the AMI group and 29 of the AP group were considered to be clinically stable and the others were unstable. Treatment of the AP group resulted in an improvement of AP in 191 patients, while in the AMI group AP was not treated in 93 and improved in 23. The participation of fixed stenosis and/or spasm of coronary arteries was examined in the AP group. There was no difference in the participation of these factors as a causative mechanism for anginal attack between UA and NUA. In conclusion, it is not pertinent to dispute that UA of the AHA is the only high risk AP for developing AMI, but for the prevention of AMI it is important to treat AP by the precise evaluation of its symptoms and by the determination of the participation of fixed stenosis or spasm of coronary arteries in each case.
D000328:Adult; D000368:Aged; D000787:Angina Pectoris / Q000175:diagnosis* / Q000601:surgery; D001026:Coronary Artery Bypass; D003329:Coronary Vasospasm / Q000150:complications; D005260:Female; D006760:Hospitalization; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000209:etiology*