A064 Spontaneous Coronary Artery Dissection: The Diagnostic Utility of Computed Tomography Coronary Angiography

Abstract

Spontaneous coronary artery dissection (SCAD) is an important cause of myocardial infarction in young to middle aged women. The utility of computed tomography coronary angiography (CTCA) in the diagnosis of SCAD has not been well established. We sought to investigate the correlation of invasive coronary angiography to CTCA in SCAD, and its use in follow-up. Consecutive patients who underwent CTCA following a diagnosis of SCAD on coronary angiography between 2010 and 2018 at our institute were included. CTCA was reported independently by two cardiologists: one with knowledge of the SCAD location, and a second blinded. A total of 32 patients with 38 non-contiguous SCAD lesions were included in our study (65.6% female, mean age 50.5±8.8 years). The left circumflex artery was most commonly affected (34.2%), and 27 lesions (71.1%) affected the distal or branch coronary vessel. The majority of SCAD lesions (78.9%) were type-2 SCAD according to the Saw classification. CTCA was performed post-SCAD at a median of 40.5 days, and 25 of 38 lesions (25.8%) were unhealed. The number of days post-SCAD till CTCA was significantly less for unhealed versus healed lesions (median 30 vs 104 days, U=73.5, p=0.005). In the blinded reporting, 18 of 25 unhealed lesions were correctly identified (sensitivity 72%), while 7 of 13 healed lesions were correctly reported as negative for dissection (specificity 53.8%). The predictive accuracy of CTCA to assess healing of SCAD increases with time. Due to the CTCA limitations of spatial resolution and the predilection for distal coronary vessels in coronary dissection, there is moderate accuracy in blinded diagnosis using CTCA, although its likely role may lie in follow-up surveillance, or symptomatic patients post-SCAD.