Coronary artery vasospasm.  A sudden spasm of the coronary arteries can feel like a heart attack.
D000959:Antihypertensive Agents / Q000627:therapeutic use; D002121:Calcium Channel Blockers / Q000627:therapeutic use; D002637:Chest Pain / Q000175:diagnosis / Q000209:etiology / Q000473:pathology; D003329:Coronary Vasospasm / Q000188:drug therapy / Q000209:etiology / Q000473:pathology*; D003331:Coronary Vessels / Q000473:pathology / Q000503:physiopathology*; D006801:Humans; D005996:Nitroglycerin / Q000627:therapeutic use; D014665:Vasodilator Agents / Q000627:therapeutic use
D000959:Antihypertensive Agents; D002121:Calcium Channel Blockers; D014665:Vasodilator Agents; D005996:Nitroglycerin