SCAD and Fibromuscular Dysplasia

Extracoronary vascular abnormalities such as fibromuscular dysplasia (FMD) have been reported in patients with SCAD, but this phenomenon is poorly understood. This project aims to assess the association between SCAD and extracoronary vascular abnormalities.

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.

Prospective imaging techniques include CT angiograms of the neck, chest, abdomen and pelvis. Retrospective review of imaging not performed at Mayo has included focused imaging of the neck, chest, abdomen or pelvis, or a combination thereof, with magnetic resonance angiography or CT angiography. Images are interpreted by two subspecialty radiologists.

Thus far, extracoronary vascular abnormalities have been detected in 60 percent of participants undergoing any form of vascular imaging, and in 70 percent of those with complete CT angiographic imaging.

Follow-ups conducted roughly two years after the initial imaging have found that about 30 percent of patients with extracoronary vascular abnormalities had SCAD recurrence, with a recurrence rate of approximately 40 percent in those without extracoronary vascular abnormalities.

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