PREVALENCE AND NATURE OF EXTRA-CORONARY ARTERIAL ABNORMALITIES IN PATIENTS WITH SPONTANEOUS CORONARY ARTERY DISSECTION VS. CONTROLS

Abstract

Abstract Objective: Spontaneous Coronary Artery Dissection (SCAD) has been associated with a high prevalence of Fibromuscular Dysplasia (FMD) and other extra-coronary arterial abnormalities. However, the prevalence, severity and clinical relevance of these abnormalities is still unclear. The objectives of the current study were: (i) to assess extra-coronary arterial abnormalities by MRA in patients with SCAD compared to controls; (ii) to compare the performance of MRA vs. CTA. Design and method: All images were jointly analysed by a vascular medicine specialist and a radiologist blinded for subject status and characteristics. In addition to qualitative analysis of images, arterial tortuosity was assessed by number of angles > 45% and tortuosity index in the main vascular beds. Results: MRA from brain to pelvis was available for 166 patients with SCAD (97% women, age at diagnosis: 44.4 ± 7.8 years) and 42 healthy controls matched for age and gender. The prevalence of FMD in patients with SCAD was 30.7% vs. 9.5% in controls (p = 0.005). In the SCAD group, the most frequently affected vascular beds were renal (13.9%), cerebrovascular (12.0%) and iliac (10.8%) arteries. Only 22% of SCAD patients had FMD lesions in 2 or more arterial beds. Nine SCAD patients (5.4%) had aneurysms vs. one (2.4%) in the control group (p = 0.5). No case of arterial dissection was identified. The prevalence and degree of arterial tortuosity was similar in cases and controls, irrespective of measurement method or arterial bed. Finally, in 35 patients explored both by CTA and MRA, the performance of MRA for detection of extra-coronary arterial abnormalities was similar to that of CTA. Conclusions: Based on the current blinded analysis of a large series of fully explored patients with SCAD compared to controls: (i) extra-coronary FMD is three times more frequent in patients with SCAD than in apparently healthy controls; (ii) FMD associated with SCAD is less often multivessel and associated with less severe arterial manifestations than “classical” FMD; (iii) patients with SCAD are not prone to extra-coronary arterial tortuosity; (iv) the performance of MRA is similar to that of CTA for detection of extra-coronary abnormalities in patients with SCAD.