A 68-year-old man was admitted to undergo elective mitral valve surgery. Although the preoperative coronary angiography was normal, the patient suffered a myocardial infarction that resulted in untreatable collapsed hemodynamics. After inferring the responsible occluded coronary artery from the segmental wall motion abnormality detected in intraoperative transesophageal echocardiography, together with the anatomy found in preoperative coronary angiography, we performed an emergency coronary artery bypass graft surgery without a new angiography. This procedure resulted in survival of a potentially life-threatening situation. In selected cases, this therapeutic strategy may lead to reduction of mortality as a result of the intraoperative myocardial infarction.