[A case of vasospastic angina: development of transient collateral circulation lessen the degree of myocardial ischemia during coronary artery spasm].

A 57-year-old man was admitted to our hospital because he had had attacks of chest pain at rest for more than a year, in spite of daily oral diltiazem (90 mg/day) and isosorbide dinitrate (15 m/day). The diagnosis of variant angina was made for him based on ST elevation in chest leads of the electrocardiogram during his first attack. However, one year later, the electrocardiograms during attacks showed only ST depression or T wave inversion in chest leads. The coronary arteriogram during spontaneous chest pain revealed that the left anterior descending artery was totally occluded at its middle portion, and that its peripheral portion was perfused by collateral circulation from the right coronary artery. The coronary arteriograms after administration of nitroglycerin were apparently normal, and no signs of collateral circulation were observed. These findings indicated that the transient collateral circulation could develop after repetitive coronary artery spasms even in the absence of significant coronary stenosis, and that it could lessen the degree of myocardial ischemia during coronary artery spasm.