From the Guidelines
The main difference between Spontaneous Coronary Artery Dissection (SCAD) and Acute Coronary Syndrome (ACS) lies in their underlying pathophysiology and presentation, with SCAD involving a tear in the coronary artery wall and ACS typically resulting from atherosclerotic plaque rupture and thrombosis. SCAD patients tend to be younger women (average age 45-53) without traditional cardiovascular risk factors, while ACS typically affects older individuals with established risk factors like hypertension, diabetes, and hyperlipidemia 1. SCAD patients often present with similar symptoms to ACS (chest pain, shortness of breath), but may have additional features like extreme emotional or physical stress triggers 1.
Key Presentation Differences
- SCAD patients are more likely to be younger women without traditional cardiovascular risk factors
- SCAD patients may have additional features like extreme emotional or physical stress triggers
- SCAD patients often present with similar symptoms to ACS, such as chest pain and shortness of breath
- Diagnosis of SCAD requires coronary angiography, which can show characteristic appearances like arterial wall staining or multiple radiolucent lumens 1
Diagnostic Approaches
- Coronary angiography is the gold standard for diagnosing SCAD
- Intravascular imaging with ultrasound or OCT can confirm the diagnosis of coronary dissection and document the extension of the disease, but should only be considered if the decision to proceed to revascularization has already been made 1
Treatment Approaches
- SCAD is generally managed conservatively using medications, rather than the interventional approaches often used in ACS, as stenting in SCAD can worsen the dissection 1
- Revascularization by PCI or CABG is indicated if the patient has ongoing ischemia involving a major coronary territory or recurrent ACS episodes on maximal medical treatment 1
- A conservative approach is favored in the absence of ongoing ischemia, and independently of how the coronary artery looks on angiography 1
From the Research
Presentation Differences between SCAD and ACS
The presentation differences between Spontaneous Coronary Artery Dissection (SCAD) and Acute Coronary Syndrome (ACS) are as follows:
- SCAD patients often present with similar symptoms to ACS patients, including chest pain 2, 3, 4
- However, SCAD patients tend to have different risk profiles, with many having fewer traditional cardiovascular disease risk factors 2, 3
- The most common presentation of SCAD is non-ST elevation myocardial infarction (NSTEMI) 4
- SCAD patients are more likely to be female, with a median age of 54 years in one study 4
- Initial electrocardiograms may not show evidence of ischemia in SCAD patients, with 85% of patients in one study having no evidence of ischemia on initial electrocardiogram 2
- Elevated troponin levels are common in SCAD patients, with 72% of patients in one study having elevated initial troponin 2
Diagnostic Considerations
- Electrocardiography should be performed immediately in patients presenting with possible ACS, and can help distinguish between STEMI and non-ST-segment elevation ACS (NSTE-ACS) 5
- High-sensitivity troponin measurements are the preferred test to evaluate for NSTEMI 5
- Coronary angiography is necessary for accurate diagnosis of SCAD, and can help identify the presence and extent of dissection 3, 4
Treatment Considerations
- Medical treatment for SCAD poses a significant challenge due to the lack of randomized studies to guide treatment 6
- Antiplatelet therapy, including dual antiplatelet therapy (DAPT), is often prescribed for SCAD patients 6
- Beta-blocking agents may be used to prevent recurrence of SCAD 6
- Statins may be used in SCAD patients due to their pleiotropic properties, although there is limited evidence to support this 6