Journal of Invasive Cardiology

ABSTRACT: Spontaneous coronary artery dissection (SCAD) is a rare but important cause of acute coronary syndromes. SCAD can cause unstable angina, acute myocardial infarction, and sudden death. Predisposing factors include atherosclerosis, the peripartum period, and structural and inflammatory conditions affecting the arterial wall. The diagnosis of coronary dissection is usually made by coronary angiography. Prompt diagnosis and treatment of patients with dissection improves survival. Therapeutic options include medical therapy, percutaneous coronary intervention, and surgery. We present a series of patients with spontaneous coronary artery dissection at our institution. The etiology, pathogenesis, diagnosis, treatment, and prognosis of patients with coronary dissection are reviewed.

J INVASIVE CARDIOL 2008;20:553–559

Spontaneous coronary artery dissection (SCAD) is a rare condition that can result in unstable angina, acute myocardial infarction, and sudden death. The diagnosis of coronary artery dissection is usually made by coronary angiography. There is increased recognition of SCAD due to frequent utilization of coronary angiography, especially in acute coronary syndromes. Management of SCAD can be challenging: clinical presentation ranges from asymptomatic to unstable angina, acute myocardial infarction, ventricular arrhythmias, and sudden death. Various treatment options have been utilized, including medical therapy, percutaneous coronary intervention (PCI), and coronary artery bypass graft surgery. The current understanding of the etiology, pathogenesis, diagnostic imaging, and approaches to management of SCAD are reviewed.

Definition. Coronary artery dissection can occur spontaneously or as a consequence of chest trauma, cardiac surgery, coronary angiography, coronary intervention, or as extension of aortic dissection. Coronary arteries are comprised of three layers: the intima, the media, and the adventitia. Dissection of the coronary artery results in separation of the layers of the arterial wall, creating a false lumen. The separation may be between the intima and the media, or between the media and the adventitia. Hemorrhage into the false lumen can impinge upon the true lumen of the coronary artery, impairing blood flow and causing myocardial ischemia, infarction, or sudden death.1–3

Incidence. The first case of spontaneous coronary dissection (SCAD) was described in 1931.4 About 300 documented cases of SCAD have been reported; this is likely an underestimate due to a significant number of spontaneous dissections presenting as sudden death.5,6 Many cases have been diagnosed only at autopsy. The overall incidence of SCAD in angiographic series ranges from 0.28 % to 1.1 %.7,8 There is a predominance of SCAD in young women.9 Seventy percent of SCAD occurs in women; of that, approximately 30% occurs in the peripartum period.9,10  The left anterior descending artery is the most frequent location of dissection. In angiographic and autopsy series, the LAD accounts for over 60% of coronary dissections.9,10