Emergency department (Day 1)	The patient presented with sudden chest pain at rest in the early morning.
	Electrocardiography showed an obvious ST-segment elevation in the leads I, aVL, and V1–5.
	Emergent coronary angiography (CAG) was performed due to acute ST-segment elevation myocardial infarction. CAG showed severe stenosis in the proximal portion of the left anterior descending coronary artery (LAD). Following administration of 5 mg isosorbide dinitrate, resolution of both LAD stenosis and ST-segment elevation were confirmed; thus, we established a diagnosis of vasospastic angina.
Day 5	The patient was discharged. He was administered benidipine (4 mg/day), isosorbide mononitrate (40 mg/day), and rosuvastatin (2.5 mg/day) and was free from any chest symptoms at the time of discharge.
Day 11	He had further chest pain and was taken to out hospital. His symptoms had already improved because of nitroglycerine administration before transport. Nicorandil (15 mg/day) and nifedipine (40 mg/day) were added to his medication regimen in the outpatient department. Following this, he had multiple recurrences of chest pain.
Day 32	He was hospitalized for titration of medication.
Day 36	Chest pain occurred and electrocardiography showed an obvious ST-segment elevation in the leads I, aVL, and V1–5. Emergent CAG showed severe organic stenosis; therefore, percutaneous coronary intervention was performed.
Day 39	He was discharged and dual antiplatelet therapy with prasugrel and aspirin was initiated.
1 year	He remained symptom-free.