Vasospasm-related myocardial infarction in young women with normal coronary arteries has infrequently been reported and vasospasm-related paroxysmal atrial fibrillation (PAF) has rarely been described. We present a 33-year-old woman with old inferior myocardial infarction and postinfarction angina at rest; the angina was accompanied by PAF and electrocardiographic ST-segment elevation in the inferior leads. Coronary angiography revealed normal coronary arteries and intracoronary acetylcholine provoked an intense and diffuse spasm of the right and left coronary artery. The spasm of the right coronary artery was associated with PAF and ST-segment elevation in the inferior leads. Frequently documented PAF, accompanied by chest discomfort and ST-segment elevation in the inferior leads, was more effectively removed with isosorbide dinitrate than with disopyramide. These data suggest that coronary vasospasm is a likely cause of myocardial infarction and even PAF, although the precise mechanism leading to PAF remains unknown.