Painless Coronary Spastic Angina First Diagnosed Perioperatively: Importance of Spasm Provocation Testing Under Medication to Confirm Optimal Therapy.

A 67-year-old man underwent surgery and, postoperatively, suddenly collapsed and developed ventricular fibrillation. Emergent coronary angiography revealed diffuse narrowing of the coronary arteries, which was reversed with isosorbide dinitrate. We attributed his aborted sudden cardiac death to coronary artery spasm. A transvenous implantable cardioverter defibrillator was implanted following the administration of vasodilators. Two years after implantation, the patient developed ventricular tachycardia, which was terminated by anti-tachycardia pacing. We then performed a spasm provocation test under medication. Intracoronary injection of acetylcholine induced spasm in the coronary artery, although no chest symptoms were observed. We diagnosed the patient with painless coronary spastic angina.