Reversible Cerebral Vasoconstriction Syndrome And Fibromuscular Dysplasia: An Epiphenomenon Or A Causal Relationship?

Fibromuscular dysplasia (FMD) is a rare non-atherosclerotic arterial disease that primarily affects middle-aged Caucasian women. Carotid web (CW) is a variant of FMD characterized by a nonatheromatous, membrane-like tissue protrusion into the carotid bulb. Reversible cerebral vasoconstriction syndrome (RCVS) is defined by severe headaches and reversible narrowing of cerebral arteries, which typically resolves within three months. While most RCVS cases have identifiable triggers, a significant portion occurs without known causes. Recent studies have reported a high prevalence of neurovascular abnormalities in RCVS patients. We present a case of a thirty-year-old woman with a sudden-onset severe headache, diagnosed with RCVS associated with carotid web. The patient had no ischemic involvement and responded well to flunarizine treatment. Follow-up imaging showed no stenosis. This case highlights a potential association between carotid web and RCVS, suggesting that FMD may contribute to vascular hyperreactivity and presents as a risk factor for RCVS. Further investigations are needed to understand the underlying mechanisms connecting these two vascular disorders. Keywords: reversible vasoconstriction syndrome; fibromuscular dysplasia; carotid web; structural abnormalities; vascular hyperreactivity.