Spontaneous Coronary Artery Dissection: Current State of the Science: A Scientific Statement From the American Heart Association

Abstract

Spontaneous coronary artery dissection (SCAD) has emerged as an important cause of acute coronary syndrome, myocardial infarction, and sudden death, particularly among young women and individuals with few conventional atherosclerotic risk factors. Patient-initiated research has spurred increased awareness of SCAD, and improved diagnostic capabilities and findings from large case series have led to changes in approaches to initial and long-term management and increasing evidence that SCAD not only is more common than previously believed but also must be evaluated and treated differently from atherosclerotic myocardial infarction. High rates of recurrent SCAD; its association with female sex, pregnancy, and physical and emotional stress triggers; and concurrent systemic arteriopathies, particularly fibromuscular dysplasia, highlight the differences in clinical characteristics of SCAD compared with atherosclerotic disease. Recent insights into the causes of, clinical course of, treatment options for, outcomes of, and associated conditions of SCAD and the many persistent knowledge gaps are presented.

Keywords: AHA Scientific Statements; coronary artery dissection, spontaneous; fibromuscular dysplasia; myocardial infarction; women.

Figure 1. Cross-sectional views of the coronary artery

A, Normal coronary artery. B, Coronary artery with intramural hematoma. C, Coronary artery with intimal tear. Spontaneous coronary artery dissection is characterized by the spontaneous formation of an intramural hematoma, which can lead to compression of the true lumen and myocardial infarction. An intimal tear may be present. Created by and used with permission from Dominic Doyle, MA.

Figure 2. Pathological appearance of spontaneous coronary artery dissection

Histological (A) and pathological (B) appearances show compression or obliteration of the true lumen (TL; arrows) by hematoma within the false lumen (FL). Used with permission from Mary N. Sheppard, Department of Cardiovascular Pathology, St. George Medical School, London, UK.

Figure 3. String-of-beads appearance of multifocal fibromuscular dysplasia (FMD)

Selective angiography of the right renal artery (A) and computed tomography angiography of the carotid (B) and renal (C) arteries. B and C are from the same patient. Findings of FMD in the right renal artery are more subtle (C, arrow) but suggest FMD given obvious beading elsewhere (B, red arrow). Also present in the bilateral internal carotid arteries is aneurysmal dilatation (aneurysm vs pseudoaneurysm; B, white arrows).

Figure 4. Frequency of presenting symptoms of acute spontaneous coronary artery dissection

VF indicates ventricular fibrillation; VT, ventricular tachycardia. Adapted from Luong et al with permission. Copyright © 2017, Wiley Periodicals, Inc.

Figure 5. Angiographic features of spontaneous coronary artery dissection

A, Type 1, multiple radiolucent lumens (arrow) or arterial wall contrast staining. B, Type 2, diffuse stenosis that can be of varying severity and length (dissection starting from arrow). C, Type 3: focal or tubular stenosis (arrow), usually <20 mm in length, that mimics atherosclerosis. Intracoronary imaging should be performed to confirm the presence of intramural hematoma or multiple lumens. D, Optical coherence tomography in type 3 (C) shows intramural hematoma (asterisk).

Figure 6. Intracoronary imaging for spontaneous coronary artery dissection

A, Optical coherence tomography shows intimal dissection (solid arrow) and intramural hematoma (asterisk). B, Intravascular ultrasonography shows intramural hematoma (dotted arrow) compressing the true lumen (asterisk).

Figure 7. Algorithm for diagnosis of spontaneous coronary artery dissection (SCAD) in the setting of acute coronary syndrome

CT indicates computed tomography; CTA, computed tomography angiography; FMD, fibromuscular dysplasia; IC, intracoronary; IVUS, intravascular ultrasonography; MRA, magnetic resonance angiography; and OCT, optical coherence tomography.

Figure 8. Algorithm for management of acute spontaneous coronary artery dissection

CABG indicates coronary artery bypass grafting; PCI, percutaneous coronary intervention; and Rx, management. ^aLeft main or proximal 2-vessel coronary artery dissection.

Figure 9. Evaluation and management of chest pain after spontaneous coronary artery dissection (SCAD).^,

^aCurrent guidelines. ^bHigh-risk anatomy indicates SCAD affecting the left main or 2 proximal coronary arteries. ^cMedical management for post-SCAD chest pain (CP) without obstructive disease: long-acting nitrates, calcium channel blockers, or ranolazine. ACS indicates acute coronary syndrome; CA, coronary angiography; CAD, coronary artery disease; CCTA, coronary computed tomography angiography; CMR, cardiac magnetic resonance; DDx, differential diagnosis; and echo, echocardiography.