Usefulness of Cardiac Magnetic Resonance Imaging in Patients With Acute Spontaneous Coronary Artery Dissection

Abstract

Cardiac magnetic resonance (CMR) has significant diagnostic and prognostic utility in myocardial infarction evaluation. However, its application in spontaneous coronary artery dissection (SCAD) is not described. Patients with confirmed SCAD who had CMR performed within 8 days of the index SCAD were reviewed. Clinical variables including demographics and medical history were recorded. CMR indexes, including myocardial delayed enhancement (MDE), microvascular obstruction, perfusion defects, left ventricular ejection fraction, and wall motion score index were measured. A total of 18 patients (all women, mean age 47.1 years) were included. Overall burden of atherosclerotic risk factors was low; 3 had a previous SCAD. Two patients underwent CMR before coronary angiography, whereas the others received CMR thereafter. Mean time between SCAD diagnosis and CMR completion was 2.7 days (range 0 to 8). Mean left ventricular ejection fraction and wall motion score index were 56.1% and 1.27, respectively. A total of 15 patients had MDE consistent with myocardial infarction in the SCAD distribution(s) identified on coronary angiography, with 8 patients having concomitant microvascular obstruction. Ten patients had transmural MDE. At follow-up (mean 386 days), all patients were alive; extracoronary vascular abnormalities were identified in 14; 6 had recurrent chest pain; and 2 had recurrent SCAD. Both patients with recurrent SCAD had no unique features on CMR to predict a future event. In conclusion, CMR provided significant value in clarifying the diagnosis and assessing for adverse sequelae after acute SCAD. Further studies are needed to determine its role in SCAD prognostication.