What is the treatment for Spontaneous Coronary Artery Dissection (SCAD)?

Treatment of Spontaneous Coronary Artery Dissection (SCAD)

Conservative medical management is the preferred initial treatment strategy for clinically stable SCAD patients, with revascularization reserved only for those with hemodynamic instability, ongoing ischemia despite medical therapy, or left main/proximal two-vessel dissection. 1

Initial Management Strategy

For Clinically Stable Patients

• Conservative therapy is strongly recommended as the primary approach for hemodynamically stable patients without high-risk anatomic features 1
• Monitor as inpatient for 3-5 days to observe for early complications or progression 1
• Most SCAD lesions heal spontaneously without intervention, and revascularization attempts carry significant risks of propagating the dissection or extending the intramural hematoma 1, 2

When Revascularization Should Be Considered

Revascularization may be necessary only in these specific scenarios:

• Hemodynamic instability (cardiogenic shock, refractory hypotension) 1
• Actively ongoing ischemia despite conservative management 1
• Left main coronary artery dissection with critical flow limitation 1
• Severe proximal two-vessel dissection with significant ischemic burden 1

Revascularization Approach When Required

• PCI should be considered first if the anatomy is technically feasible, though success rates are lower than in atherosclerotic ACS due to risks of wire-induced propagation and stent-related complications 1, 2
• CABG should be considered for left main involvement, multivessel disease, or when PCI is technically unfavorable, though acute graft closure occurs in up to 30% of cases 1
• The choice between PCI and CABG depends on local expertise and technical considerations 1

Medical Therapy

Beta-Blockers (Strongly Recommended)

• Beta-blockers are the cornerstone of long-term medical therapy as they have been significantly associated with reduced risk of recurrent SCAD 1, 3, 4
• Continue indefinitely for both cardiovascular protection and SCAD recurrence prevention 1, 3

Antihypertensive Therapy

• Aggressive blood pressure control is essential as hypertension is an independent predictor of recurrent SCAD 1, 3, 4
• Target blood pressure <130/80 mmHg 1

Antiplatelet Therapy

• Aspirin monotherapy is generally safe and beneficial for conservatively managed SCAD patients 2
• Dual antiplatelet therapy (DAPT) is recommended for patients who undergo PCI, following standard post-PCI protocols 1, 2
• For conservatively managed patients, short-term DAPT (if initiated) followed by longer-term single antiplatelet therapy with aspirin may be considered, though the benefit of DAPT in non-revascularized SCAD is questionable 1, 2

Medications to AVOID

• Fibrinolytics are contraindicated as they can extend the dissection and worsen outcomes 2
• Anticoagulants are contraindicated due to risk of expanding the intramural hematoma 2
• Glycoprotein IIb/IIIa inhibitors are contraindicated 2
• Statins, ACE inhibitors, and ARBs are NOT routinely recommended in the absence of left ventricular dysfunction or other specific indications 2

Diagnostic Confirmation

Angiographic Classification

SCAD has three angiographic types that guide management decisions:

• Type 1: Multiple radiolucent lumens or arterial wall contrast staining 1, 3
• Type 2: Long diffuse smooth narrowing of varying severity and length 1, 3
• Type 3: Focal or tubular stenosis (<20mm) mimicking atherosclerosis 1, 3

Intracoronary Imaging

• OCT or IVUS should be used when the diagnosis is uncertain on angiography alone, particularly for Type 3 SCAD that mimics atherosclerosis 1, 3
• These modalities confirm the presence of intramural hematoma or double lumen 1, 3
• Use cautiously as the imaging catheter itself can propagate dissection 1

Follow-Up Management

Surveillance for Recurrent Symptoms

• Coronary CT angiography (CCTA) may be considered for follow-up in patients with persistent or recurrent symptoms, even without evidence of recurrent MI or ischemia 1
• Repeat coronary angiography at 6-8 weeks can be considered if diagnostic uncertainty persists 1

Screening for Associated Conditions

• All SCAD patients should undergo extracoronary vascular screening from brain to pelvis, as fibromuscular dysplasia (FMD) is present in up to 72% of SCAD patients 1, 4
• Screen for intracranial aneurysms (present in 14-23% of SCAD patients), renal artery FMD, and carotid artery abnormalities 1

Special Populations

Pregnancy-Associated SCAD

• Hormonal therapy is contraindicated in patients who develop SCAD during pregnancy 2
• Future pregnancy is discouraged in this population due to high recurrence risk 2

Women Under 60 Years

• SCAD accounts for 22-35% of ACS cases in women under 60 years of age 1, 3, 4
• Over 90% of SCAD cases occur in women 3, 4

Common Pitfalls to Avoid

• Do not routinely revascularize stable SCAD patients as this is associated with worse outcomes compared to conservative management 1
• Avoid using PCI wires aggressively as they can propagate the dissection plane 1
• Do not assume atherosclerotic ACS management principles apply - SCAD requires a fundamentally different approach 1, 2
• Do not overlook emotional and physical stress triggers as SCAD is often precipitated by these factors 3, 4
• Do not miss screening for FMD and other arteriopathies as these have major implications for recurrence risk and overall vascular health 1, 4