Reviews

Spontaneous coronary artery dissection: An often unrecognized cause of acute coronary syndrome

Author and Disclosure Information

ABSTRACT

Spontaneous coronary artery dissection (SCAD), an intramural hemorrhage leading to a separation of the layers of the coronary artery wall, is traditionally considered a rare condition associated mainly with pregnancy but is likely underdiagnosed in other settings. Its recognition by coronary angiography is key. Medical management is usually indicated, except in certain circumstances in which coronary artery bypass grafting or percutaneous coronary intervention should be considered.

KEY POINTS

  • SCAD often presents with symptoms of acute coronary syndrome but can be asymptomatic or cause sudden death.
  • Management is generally conservative, but a left main or severe proximal 2-vessel dissection, hemodynamic instability, or ongoing ischemic symptoms may warrant revascularization.
  • All patients with SCAD should be screened for other vascular problems, especially fibromuscular dysplasia.
  • Long-term aspirin therapy and 1 year of clopidogrel are recommended after an episode of SCAD.


 

References

A 12-lead electrocardiogram showed ST-segment elevation of more than 2 mm in leads V2, V3, V4, and V5 (arrows), with no reciprocal changes.

Figure 1. A 12-lead electrocardiogram showed ST-segment elevation of more than 2 mm in leads V2, V3, V4, and V5(arrows), with no reciprocal changes.

A 55-year-old woman with hypertension presented with sudden onset of severe pressure-like chest pain that started when she was taking a bath. The pain radiated to her back and was associated with nausea.

A 12-lead electrocardiogram (Figure 1) showed ST-segment elevation of more than 2 mm in leads V2, V3, V4, and V5, with no reciprocal changes.

Coronary angiography before treatment

Figure 2. Coronary angiography before treatment revealed a long segment of diffuse, smooth narrowing of the mid-left anterior descending coronary artery that did not reverse after administration of intracoronary nitroglycerin. Inset, artist’s illustration showing coronary dissection.

In view of her ongoing severe chest pain, she was given aspirin and ticagrelor and was taken for emergency cardiac catheterization. Left ventriculography showed hypokinesis in the mid-anterior, distal anterior, apical, and distal inferior chamber walls. Coronary angiography (Figure 2) revealed a long segment of diffuse, smooth narrowing of the mid-left anterior descending coronary artery that did not reverse after administration of intracoronary nitroglycerin.

Based on the classic angiographic appearance and the absence of atherosclerotic disease in other coronary arteries, type 2 spontaneous coronary artery dissection (SCAD) was diagnosed.

CORONARY ARTERY WALL SEPARATION

SCAD is defined as a nontraumatic, noniatrogenic intramural hemorrhage leading to separation of the coronary arterial wall and the formation of a false lumen. The separation can occur between any of the coronary artery wall layers and may or may not involve an intimal tear. The bleeding may result in an intramural hematoma and possible narrowing of the arterial lumen. Depending on the severity of narrowing, blood supply to the myocardium could be compromised, resulting in symptoms of ischemia.1

SCAD usually involves a single coronary artery, although multiple coronary artery involvement has been reported.2

CASE CONTINUED: MANAGEMENT

After stenting, the vessel regained normal flow.

Figure 3. After stenting, the vessel regained normal flow. Inset, artist’s illustration showing a stent in place.

Conservative management is generally recommended for SCAD. An initial decision was made to continue medical management alone. But because the patient continued to have severe chest pain that was unresponsive to intravenous nitroglycerin and intravenous morphine and was accompanied by frequent episodes of nonsustained ventricular tachycardia during cardiac catheterization, the management team decided to proceed with percutaneous coronary intervention (PCI). Implantation of a 2.25-by-38-mm drug-eluting stent in the left anterior descending artery was successful, resulting in return of normal flow (Thrombolysis in Myocardial Infarction [TIMI] score 3) and only a small distal residual non-flow-limiting dissection (Figure 3).

The patient recovered completely and was discharged home with plans to return for outpatient imaging for fibromuscular dysplasia.

Next Article:

Is neuroimaging necessary to evaluate syncope?

Related Articles