Clinical characteristics and long-term prognosis of patients with variant angina. A comparative study between western and Japanese populations.

To determine the factors influencing the prognosis of variant angina, the clinical characteristics and long-term prognosis of 158 consecutive Japanese patients were examined and compared with those in previous major western studies (Pisa, Montreal, and Duke studies). The Japanese patients were characterized by relatively low prevalences of coronary risk factors, significant coronary stenoses and previous myocardial infarction. Survival and survival without myocardial infarction for the entire group or for the subpopulation with significant coronary artery disease were significantly better in the Japanese population than in the western populations; however, in the subpopulation without significant coronary artery disease, the prognosis was excellent in all four studies. If the prevalence of coronary artery disease was corrected for the Japanese population, there would be no difference in the prognosis between the Japanese and the western populations. It is concluded: (1) the overall prognosis of variant angina may be better in Japanese patients, and (2) coronary artery disease appears to be the strongest prognostic factor for assessing the differences in the prognosis between the Japanese and the western populations.