Perioperative coronary vasospasm has been recognized as a possible cause of myocardial infarction or low output syndrome after open heart operations. A 57-year-old male suffered cardiogenic shock immediately after off-pump coronary artery bypass grafting surgery. Emergent angiography performed under intraaortic balloon pumping and percutaneous cardiopulmonary support revealed severe multivessel coronary vasospasm which was effectively treated with a high dose intracoronary administration of isosorbide dinitrate. Emergent angiography for patients with cardiogenic shock after open heart operation is feasible and effective for the diagnosis and treatment of perioperative coronary vasospasm.