Spontaneous coronary artery dissection is a rare cause of myocardial infarction associated with a significant high morbidity and mortality. It usually occurs in relatively young patients and it is frequently found at autopsy. We report a case of a 42-year-old woman, who underwent resection of subaortic diaphragm ten years earlier presenting with postero-lateral myocardial infarction. Coronary arteriography revealed a dissection of the left main stem extending distally to the left anterior descending artery (LAD) and circumflex artery (Cx); occlusion of the postero-lateral branch of the Cx; severe aortic valve regurgitation and ascending aortic aneurysm. She was successfully operated on in emergency and underwent myocardial revascularization and separate replacement of the aortic valve and the ascending aorta. In this specific case of coronary dissection and severe aortic regurgitation it is mandatory to perform surgery in emergency to limit infarction evolution and avert loss of life.