Fibromuscular Dysplasia and Cerebrovascular Dissection: Insights from a Multicenter Cohort

Background Fibromuscular dysplasia (FMD) is a non‐inflammatory arteriopathy that may result in arterial stenosis, dissection, aneurysm, and tortuosity. Data remain limited on clinical features and outcomes of patients with FMD presenting with spontaneous cervical artery dissection (SCeAD). This study aimed to describe the characteristics and long‐term outcomes of this population. Methods We conducted a retrospective multicenter cohort study of patients diagnosed with both SCeAD and FMD at three U.S. comprehensive stroke centers (2018‐2023). Patients were identified through hospital records and vascular registries. Diagnosis of FMD and SCeAD was confirmed through imaging review by vascular neurologists or cardiologists. Outcomes included recurrent dissections, cardiovascular events (ischemic stroke, transient ischemic attack, myocardial infarction, subarachnoid hemorrhage) and mortality. Results Among 1,632 patients with SCeAD, 97 (6%) had FMD diagnosis. The cohort was predominantly female (91%) and median age at FMD diagnosis was 50 years(IQR 42‐63). Carotid dissections were more frequent than vertebral dissections (86%vs.27%, p<0.001). Multiple dissections occurred in 32 patients (33%): 24 (75%) had bilateral dissections, 4(13%) had recurrent dissections in the same artery, and 7 (22%) had dissections in other vascular beds including the renal, iliac, mesenteric, and coronary arteries. Younger age OR 0.945; 95%CI 0.908‐0.983; p=0.005 and classical FMD “beading” on imaging OR 3.06; 95%CI 1.28‐7.36; p=0.012 were associated with multiple dissections. Aneurysms were detected in 27%, more frequently in patients with multiple dissections OR 1.66; 95%CI 1.02‐2.71;p=0.04. Most patients were discharged on single (49%) or dual (29%) antiplatelet therapy and 22% received anticoagulation with no significant differences in event rates. Over a mean follow‐up of 5±2.5 years, 13% developed recurrent dissections and 28% experienced cardiovascular events. Recurrent dissections were associated with future cardiovascular events OR11.56; 95%CI 2.22‐60.07; p=0.004. Conclusions FMD should be considered in patients presenting with SCeAD, particularly middle‐aged women with multifocal dissections and no traditional vascular risk factors. There is an increased risk of dissection recurrence, future cardiovascular events and harboring aneurysms. These findings highlight the need for further prospective studies that can guide surveillance and management strategies for this high‐risk population.