SCAD and Extracoronary Vascular Abnormalities Such as Fibromuscular Dysplasia

Abnormalities in arteries other than the coronary arteries (extracoronary vascular abnormalities) — such as fibromuscular dysplasia (FMD) — have been reported in patients with SCAD, but this phenomenon is poorly understood. The SCAD Research Program has proposed a novel screening protocol to detect abnormalities in arteries other than the coronary arteries in patients with SCAD and assess the association between the two conditions.

The protocol for this project includes prospective imaging as well as retrospective review of vascular imaging among participants with confirmed SCAD receiving outpatient evaluations at Mayo Clinic.

Mayo Clinic SCAD researchers are working to identify the optimal screening and prevalence of extracoronary vascular abnormalities. In Mayo Clinic's dedicated SCAD CT angiogram protocol, participants receive an outpatient exam, consisting of a single CT angiogram of the neck with their arms down, immediately followed by another CT angiogram of the chest, abdomen and pelvis with their arms up. All exams are performed with radiation dose modulation techniques and reviewed by dedicated vascular radiologists.

Extracoronary vascular abnormalities have been detected in more than two-thirds of the scanned patients. Specific types of abnormalities identified include FMD, aneurysms, dissection and aortic tortuosity, and have been seen in the aorta, carotid, vertebral, iliac, renal and mesenteric arteries.

The data thus far suggest that the majority of patients with SCAD have coexisting extracoronary vascular abnormalities, leading the research team to hypothesize that SCAD may be a manifestation of underlying systemic vascular disease.