Delayed Cerebral Infarction is Systematically Associated with a Cerebral Vasospasm of Large Intracranial Arteries

Whether delayed cerebral infarction (DCIn) after aneurysmal subarachnoid hemorrhage (aSAH) is driven by large artery vasospasm is still controversial.To study the association between DCIn and vasospasm by using quantitative assessment of vasospasm up to distal arteries with time and territorial-based correlation.Clinical and imaging data of 392 patients with aSAH treated at our center between 2012 and 2017 were reviewed. DCIn was defined as any cerebral infarction occurring within 3 to 21 d after ictus and not related to other specific cause. In patients with DCIn, vasospasm was assessed within 24 h around DCIn for each cerebral artery up to the end of the 2nd segments. DCIn and vasospasm analyses were blinded.DCIn was found in 11% of patients (inter-rater k = 0.90, computed tomography (CT)-scan = 100%, follow-up MRI = 91%). Vasospasm was quantified in 258 artery territories including 66 with and 192 without DCIn (DSA = 93%, computed tomography angiography = 7%). Vasospasm was more severe in DCIn than in non-DCIn territories (60% [55-69] vs 20% [0-50], P < .001). Vasospasm was associated with DCIn in a "dose-dependent" manner (P for trend = .022). Every DCIn territory had a vasospasm ≥ 50%, including 39% only of distal artery segments. Only 9% of non-DCIn territories had vasospasm ≥ vasospasm in DCIn territories.The necessary association between severe vasospasm and DCIn in our study brings additional arguments in favor of large artery vasospasm (especially of distal segments) as a major determinant of DCIn and a potential therapeutic target.