Aortic Dimensions Are Larger in Patients With Fibromuscular Dysplasia.

Background Fibromuscular dysplasia (FMD) is a disease of unknown etiology that causes stenosis, aneurysmal dilatation, and dissection of vascular beds. Known to affect medium-sized arteries, FMD is not typically considered to affect the aorta. We tested the hypothesis that aortic size in FMD is abnormal compared with age- and sex-matched controls. Methods and Results Medical records and computed tomography angiography images were reviewed in female patients with a diagnosis of FMD who were seen in the vascular medicine clinic at Emory Healthcare. Aortic dimensions were measured at 6 different landmarks. Using 2 sample t tests, the aortic measurements and height-indexed measurements were compared with published normal values in healthy women of a similar age. A total of 94 female patients were included in the study. The median age was 57 (interquartile range, 50-65). FMD involvement was present most commonly in the extracranial carotid (77.7%) and renal (43.6%) arteries. All 6 aortic segments were found to be larger in both absolute measures and height-indexed measures in the FMD population ( P <0.001). The largest differences were observed within the absolute measures of the sinotubular junction with mean±SD (mm) (29.9±4.1) versus (27±2.5), ascending aorta (32.7±4.4) versus (30.0±3.5), and descending aorta (24.7±3.0) versus (22.0±2.0) ( P <0.001). Conclusions Aortic diameters in female patients with FMD are larger when compared with published age- and sex-matched normal values. These findings suggest that FMD may also affect the large-sized arteries.