Fifty-five patients were enrolled in this study. However, four patients and two patients who had no significant ST-segment shift and had transient atrial fibrillation, respectively, during the LAD spasm were excluded from the study, although five of the six patients had transient U-wave inversion. Thus, 49 patients formed the study group. Of these 49 patients, 27 patients (ST-segment elevation group) had ST-segment elevation during LAD spasm (19 men and 8 women; mean age, 62 ± 9 years; age range, 44 to 75 years), and the remaining 22 patients (ST-segment depression group) had ST-segment depression during the attack (13 men and 9 women; mean age, 60 ± 9 years; age range, 46 to 75 years). Of the 27 patients in the ST-segment elevation group, 24 patients had chest pains typical of vasospastic angina pectoris, and 1 patient had atypical chest pains. The remaining two patients did not have chest pain. In the ST-segment depression group, 20 patients had chest pains typical of vasospastic angina, 1 patient had atypical angina, and the remaining patients had no angina. Chest pain was considered to be typical of vasospastic angina when it had characteristics of angina pectoris in its quality, location, and duration,15 and mainly developed from midnight to early morning. In eight patients in the ST-segment elevation group and five patients in the ST-segment depression group, ECGs that showed significant ST-segment deviation were obtained during spontaneous anginal attacks. For patients without angina in both groups, the indication for coronary angiography was a positive exercise stress test result. That is, during multistage submaximal treadmill exercise testing of asymptomatic individuals, patients whose resting ECG showed abnormalities in the ST- segment or T wave had ST-segment depression of ≥ 0.1 mV below the baseline, and patients whose resting ECG was normal had horizontal or downsloping ST-segment depression of ≥ 0.1 mV, measured 0.08 s after the J-point using the PQ-segment as the isoelectric line. No patients had ST-segment elevation during exercise stress testing. As shown in Table 1
, age and gender were similar. There were no differences in body mass index, left ventricular mass index, or risk factors for coronary artery disease between the two groups.