Two types of arteriopathies, arteriomegaly and aneurysms, frequently develop at diverse locations in vertebrobasilar dolichoectasia patients: A retrospective analysis and a meta-analysis

Background: Past studies have reported that vertebrobasilar dolichoectasia (VBD) patients may develop similar arteriopathies other than the vertebrobasilar system. However, the details of these VBD-related arteriopathies are still unclear.

Methods: We retrospectively enrolled patients diagnosed with VBD at two stroke centers in Japan between January 2012 and December 2023. Arteries of the brain and the trunk were assessed for arteriopathies resembling VBD by computed tomography angiography. Vessel sizes were defined as the maximum diameter measured on the cross-sectional plane. Age, sex, and race-matched stroke patients were recruited as a control group. Arterial ectasias were subdivided into arteriomegaly, which was defined as diffuse ectasia more than 1.5 times the mean size of the controls, or focal ectasia (i.e., aneurysms). A systematic review of PubMed and Scopus was performed between the date of the databases' inception and June 2024 using the keywords (vertebrobasilar OR basilar OR vertebral) AND (dolichoectasia OR dolichoectatic OR serpentiform OR serpentine OR "fusiform aneurysm"). The prevalences of VBD-related vasculopathy at each anatomical location were meta-analyzed by a random-effect model.

Results: Nineteen VBD patients were enrolled. Radiological data of the brain and the trunk were available in 19 and 7 patients. The median VBD size was 13.4 (IQR, 11.3-19.6) mm. The vessel sizes of the anterior circulation were significantly larger in VBD patients than in the controls [internal carotid artery (ICA), 6.7 (IQR, 5.4-7.8) vs. 3.8 (IQR, 3.5-4.0) mm; M1 segment, 3.2 (IQR 2.9-4.2) vs. 2.5 (IQR 2.4-2.6) mm; P < 0.0001 in both]. These arterial sizes significantly correlated to contralateral counterparts [ICA, ρ = 0.86, P < 0.0001; M1, ρ = 0.62, P = 0.0049]. At the trunk, arteriomegaly or aneurysms were identified in five (71.4 %) patients. The systematic review identified 11 case series, including ours, that reported the prevalences of arteriopathies outside the vertebrobasilar system. The prevalences of arteriomegaly or aneurysms at the anterior circulation have been most frequently reported in 7 case series followed by those at the aorta and coronary artery in 6 and 2, respectively. Meta-analyses corroborated the high prevalences of arteriopathies at the anterior circulation (23 %; 95 % CI, 10-39 %), aorta (37 %; 95 % CI, 21-54 %), and coronary artery (43 %; 95 % CI, 23-65 %).

Conclusions: Our study suggests that the pathogenesis underlying VBD affects diverse arterial regions and causes two types of arterial remodeling, arteriomegaly and aneurysms.