Increased prevalence of blister aneurysm formation during the COVID-19 pandemic

Intracranial blister aneurysms are a rare and an historically difficult to treat subset of aneurysms. They are distinct from typical saccular aneurysms with different pathophysiology and treatment options.

A prospectively maintained database of subarachnoid hemorrhage patients was queried for those presenting prior to the pandemic (2017-2019), and those presenting during the height of the pandemic in our locality (2021). Aneurysm characteristics and patient demographics associated with rupture risk/formation were collected.

334 aneurysmal subarachnoid hemorrhage patients were reviewed. 86 of these patients presented in 2021, with a statistically significant increase in the proportion of ruptured ICA blister aneurysms as compared to 2017-2019 (7/86, 8% vs 5/248, p = .02). Mean patient age, presenting grade, other aneurysm location proportions, aneurysm size, and incidence of delayed cerebral ischemia were not different between the groups.

Patients presenting with SAH during the height of the SARS-CoV-2 pandemic in 2021 were more likely to have ICA blister type aneurysms.