Coronary artery anomalies are identified in approximately 1% of patients who undergo angiography; among these, circumflex branch agenesis represents 0.003%. A 38-year-old woman was brought to our emergency department with clinical findings suggestive of acute myocardial infarction. Absence of circumflex branch was reported during angiography. Further analysis showed great vessel abnormalities: the presence of a left superior vena cava, a left arterial trunk of abnormal origin, and a small cerebral aneurysm. To our knowledge, this is the only reported case with such vascular anomalies.