Mortality in the total occlusion of the left main coronary artery is very high, and the few cases who lived reported were very ill and symptomatic patients. We present a case with angiographic documentation of total occlusion of the left main coronary artery in a patient without angina and with a normal rest electrocardiogram in which a syncope was the only symptom. Severe isolated silent ischemia was induced during an exercise test. Total occlusion of the left main coronary artery associated to silent myocardial ischemia without cardiac failure has never been previously reported.