Abstract

A spontaneous coronary artery dissection (SCAD) (occasionally coronary artery dissection) is a rare, sometimes fatal traumatic condition, with eighty percent of cases affecting women. One of the coronary arteries develops a tear, causing blood to flow between the layers which forces them apart. Studies of the disease place the mortality rate at around 70%.

SCAD is a primary cause of myocardial infarction (MI) in young, fit, healthy women (and some men) with no obvious risk factors. These can often occur during late pregnancy, postpartum and peri-menopausal periods.

Signs and symptoms

The symptoms are often very similar to those of myocardial infarction (heart attack), with the most common being persistent chest pain.

Causes | SCAD

There is evidence to suggest that a major cause of spontaneous coronary artery dissection (SCAD) is related to female hormone levels, as most cases appear to arise in pre-menopausal women, although there is evidence that the condition can have various triggers. Other underlying conditions such as hypertension, recent delivery of a baby, fibromuscular dysplasia and connective-tissue disorders (e.g., Marfan syndrome and Ehlers-Danlos syndrome) may occasionally result in SCAD. There is also a possibility that vigorous exercise can be a trigger. However, many cases have no obvious cause.

Pathophysiology

Coronary artery dissection results from a tear in the inner layer of the artery, the tunica intima. This allows blood to penetrate and cause an intramural hematoma in the central layer, the tunica media, and a restriction in the size of the lumen, resulting in reduced blood flow which in turn causes myocardial infarction and can later cause sudden cardiac death.

Diagnosis

A selective coronary angiogram is the most common method to diagnose the condition, although it is sometimes not recognised until after death. Intravascular ultrasound (IVUS) is also used as it is able to more easily differentiate the condition from atherosclerotic disease.

Treatment

Treatment is varied depending upon the nature of the case. In severe cases, coronary artery bypass surgery is performed to redirect blood flow around the affected area. Drug-eluting stents and thrombolytic drug therapy are less invasive options for less severe cases.