Characteristic findings of acute spontaneous coronary artery dissection by cardiac computed tomography

Background: Spontaneous coronary artery dissection (SCAD) is an infrequent cause of acute coronary syndrome (ACS); however, its detection carries relevant clinical implications. Cardiac computed tomography (CCT) has been found to be useful for follow-up, but data during the acute phase are scarce. Thus, our aim was to evaluate the early diagnostic ability of CCT to detect SCAD. Methods: We retrospectively analyzed all the in-hospital CCT performed in a prospective cohort of patients with SCAD from 2012 to 2016. An independent expert blindly evaluated the studies and described the radiologic characteristics of the lesions. These features were compared with the invasive coronary angiography (ICA) and optical coherence tomography (OCT) findings. Results: 18 lesions were analyzed from 12 episodes identified in 11 patients (100% females; median age of 57 years old). CCT recognized the presence of SCAD in 14 (78%) of the lesions, with four different morphological patterns. Most commonly (10, 71%) SCAD presented as a diffuse lumen narrowing surrounded by a 'sleeve-like' wall thickening, which corresponded to intramural hematoma in OCT evaluation. When compared with ICA, CCT showed a positive correlation (Spearman's Rho = 0.775; P = 0.001) and excellent concordance (ICC = 0.8; P = 0.004) in stenosis grading, but not for lesion length and minimal luminal area. Conclusion: CCT was able to identify the presence of SCAD in most of the patients in the acute phase of this elusive and challenging clinical entity. In addition, in this setting, CCT revealed unique and distinct radiologic features and provided a precise assessment of lesion severity.