Prevalence and Outcomes of Bicuspid Aortic Valve in Patients With Aneurysmal Sub‐Arachnoid Hemorrhage: A Prospective Neurology Registry Report

Background Intracranial aneurysms are reported in 6%–10% of patients with bicuspid aortic valve (BAV), and routine intracranial aneurysm surveillance has been advocated by some. We assessed the prevalence and features of the most important patient‐outcome: aneurysmal sub‐arachnoid hemorrhage (aSAH), as compared with controls without aSAH, and tricuspid aortic valve (TAV) with aSAH. Methods and Results Adult patients with accurate diagnosis of aSAH and at least one echocardiogram between 2000 and 2019 were identified from a consecutive prospectively maintained registry of aSAH admissions. Controls without a diagnosis of SAH were age‐ and sex‐matched. BAV prevalence was confirmed echocardiographically. Severity of aSAH was categorized using modified Fisher and World Federation of Neurological Scale. Neurologic outcome was assessed using modified Rankin score. A total 488 aSAH cases and 990 controls were identified and BAV status was confirmed. Prevalence of BAV in patients with aSAH was 1.2% (6/488) versus 3.5% (35/990) in controls, P=0.01. BAV+aSAH were noted to be younger than TAV+aSAH (56±11 versus 68±14; P=0.03) with smaller aneurysms (5±2 versus 7±4; P=0.31). The severity of aSAH was lesser in BAV+aSAH than TAV (modified Fisher grade>2 50% versus 74%; P=0.19, World Federation of Neurological Scale grade>3 17% versus 36%; P=0.43). BAV+aSAH had less severe neurologic disability (modified Rankin score 3%–6 33% versus 49% in TAV; P=0.44) and comparable in‐hospital mortality rates (P=0.93). BAV had lower odds for aSAH on multivariate analysis (odds ratio 0.23[CI 0.08–0.65]; P=0.01). Conclusions Prevalence of BAV was 3 times lower in the aSAH registry than in controls without aSAH. BAV+aSAH had clinically smaller aneurysms, clinically smaller bleeds, and better neurologic outcome as compared with TAV+aSAH, which needs to be confirmed in larger studies. These findings argue against routine surveillance for intracranial aneurysms in patients with BAV without aortic coarctation.