What is SCAD?

SCAD, spontaneous coronary artery dissection, is defined as a tear in the coronary arterial wall that is not related to trauma or medical instrumentation. This spontaneous tear can occur from a disruption of the innermost lining of the arterial wall, causing blood to rush in from the lumen (center channel of the artery) into the arterial wall. Alternatively, separation of the arterial walls can occur from bleeding due to spontaneous rupture of small vessels that feed the arterial wall. The buildup of blood inside the arterial wall compresses the lumen, blocking blood flow to the heart.

SCAD Mechanism

How frequent is SCAD?

SCAD is considered to be rare in the general population, although it has been under-diagnosed and the true prevalence is unknown. Overall, it is an infrequent cause and accounts for only up to 4% of heart attacks (1). However, SCAD proportionally causes a higher number of heart attacks in young women, where ~25% of women ≤50 years-old had heart attacks due to SCAD in one series (2).

Who is affected by SCAD?

SCAD predominantly affects women in ~90% of cases, and can affect all ages and races. Historically, it was thought to affect mostly young women, but recent studies showed that older and postmenopausal women could also suffer SCAD, even though the majority are <65 years-old (3). Affected patients tend not to have the typical risks for heart disease such as diabetes, smoking, or obesity. Instead, there are different risk factors for SCAD, including possible genetic predispositions to arterial weakening or fragility. The majority of cases have been sporadic without familial associations, but the genetic basis of SCAD has not been adequately explored.



1. Nishiguchi T, Tanaka A, Ozaki Y, Taruya A, Fukuda S, Taguchi H, Iwaguro T, Ueno S, Okumoto Y, Akasaka T. Prevalence of spontaneous coronary artery dissection in patients with acute coronary syndrome. European heart journal. Acute cardiovascular care. 2013
2. Saw J, Aymong E, Mancini J, Sedlak T, Starovoytov A, Ricci D. Nonatherosclerotic coronary artery disease in young women. Can J Cardiol. 2014
3. Saw J, Aymong E, Buller CE, Sedlak T, Starovoytov A, Ricci D, Humphries K, Mancini J. Nonatherosclerotic spontaneous coronary artery dissection: Association with predisposing and precipitating conditions, and cardiovascular outcomes. J Am Coll Cardiol. 2014;63:A4
4. Vijayaraghavan R, Verma S, Gupta N, Saw J. Pregnancy-Related Spontaneous Coronary Artery Dissection. Clinician Update. Circulation 2014;130(21):1915-20.

DISCLAIMER: This webpage presents information regarding what we have learned from our SCAD cohort.
Our suggested management may or may not apply to individual patients presenting with SCAD.
Patients should contact their health care professionals for specific individual management of their condition.