Vascular Disease Patient Information Page: Spontaneous coronary artery dissection (SCAD).

The heart is the pumping organ of the circulatory system. The coronary arteries are the blood vessels that supply oxygen and nutrient-rich blood to the heart. Blockage of a coronary (heart) artery can lead to a heart attack (myocardial infarction). These artery blockages are usually caused by atherosclerosis, or plaque build-up in the arteries. Spontaneous coronary artery dissection, commonly referred to as SCAD, is another cause of heart attack. SCAD is not caused by plaque. Instead, a heart attack due to SCAD occurs when there is a tear (dissection) of, or bleed into, the wall of a coronary artery, causing a severe blockage (Figure 1). By definition, SCAD occurs spontaneously, meaning it develops out of the blue and not due to physical trauma or other injury to the artery. SCAD can occur in both men and women, but more commonly affects women. It has recently been recognized as an important cause of heart attack in young and middleaged women (typically in their 40s to 50s) who have few or none of the risk factors associated with atherosclerotic heart or vascular disease.