Spontaneous coronary artery dissection

Spontaneous coronary artery dissection (SCAD) is an uncommon but potentially lethal condition in which one of the coronary arteries that supply the heart, spontaneously develops a blood collection, or hematoma, within the artery wall due to a tear in the wall. SCAD is one of the arterial dissections that can occur.^[1]

SCAD is a major cause of

SCAD symptoms are the result of a restriction in the size of the lumen of the affected coronary artery. A bleed within the wall of the artery (tunica intima) originating from the microvessels that perfuse this muscular layer (vasa vasorum) leads to a collection of blood, or hematoma, between the layers of the artery wall.^[1] The hematoma pushes close the lumen, preventing blood from flowing to the heart muscle (

Involvement of the Vasa Vasorum

While the molecular mechanisms that underpin SCAD are still poorly understood, studies have implicated dysfunction of the

Diagnosis

Given the demographics of SCAD, it is important to maintain a high index of suspicion for the condition in otherwise low-risk women presenting with symptoms of

Intracoronary imaging (ICI), consisting of

Some studies propose coronary CT angiography to evaluate SCAD in lower-risk people, with research into the approach ongoing.^[4][17]

Management

Management depends upon the presenting symptoms. In most people who are hemodynamically stable without high-risk coronary involvement, conservative medical management with blood pressure control is recommended.^[4][20][21] In these people, especially if angiography demonstrates adequate coronary flow, the most likely course usually leads to spontaneous healing, often within 30 days.^[22] Anti-coagulation should be discontinued upon diagnosis of SCAD on coronary angiography as continuation of anti-coagulation may lead to hematoma and dissection propagation.^[18]

In cases involving high-risk coronaries, hemodynamic instability, or a lack of improvement or worsening after initial attempts at treatment, urgent treatment with

People with SCAD have a low in-hospital mortality after treatment. However, the lesion may worsen after leaving the hospital within the first month.[17]^[25] One study suggested a 1.2% mortality rate following SCAD but a 19.9% risk for either death, heart attacks, or strokes.^[26] Even afterwards, SCAD has a high recurrence risk at 30% within 10 years, often at a different site than the initial lesion - meaning that stents placed in the location of the first lesion may not protect against a second.^[17] Given the lack of consensus on the cause of SCAD, prevention of future SCAD may include medical therapy, counseling about becoming pregnant again (for those who had pregnancy-associated SCAD), or avoidance of estrogen therapy.^{[citation needed]}

Preventative Research

Research is currently being carried out to identify what causes SCAD, in an effort to prevent recurrence, or potentially onset in at risk family members of SCAD patients. Australian researchers at the Victor Chang Cardiac Research Institute, for example, have generated induced pluripotent stem cell (iPSC) lines from patients to model SCAD 'in a dish'. ^[27]

Epidemiology

SCAD is the most common cause of

SCAD was first described in the year 1931, at postmortem examination, in a 42-year-old woman.[29]^[28] Due to a lack of recognition and diagnostic technology though, SCAD literature until the 21st century included only case reports and series.^[28] With the recent advent of coronary angiography and intracoronary imaging, recognition and diagnosis of SCAD has greatly increased, especially in the 2010s.^[28]

See also

• Dissection (medical)
• Aortic dissection
• Kounis syndrome

References