Background and purpose: The long-standing concept that delayed cerebral infarction after aneurysmal subarachnoid hemorrhage results exclusively from large artery vasospasm recently has been challenged. We used data from the CONSCIOUS-1 trial to determine the relationship between angiographic vasospasm and cerebral infarction after subarachnoid hemorrhage.
Methods: We performed a post hoc exploratory analysis of the CONSCIOUS-1 data. All patients underwent catheter angiography before treatment and 9±2 days after subarachnoid hemorrhage. CT was performed before and after aneurysm treatment, and 6 weeks after subarachnoid hemorrhage. Angiograms and CT scans were assessed by centralized blinded review. Angiographic vasospasm was classified as none/mild (0%-33% decrease in arterial diameter), moderate (34%-66%), or severe (≥67%). Infarctions were categorized as secondary to angiographic vasospasm, other, or unknown causes. Logistic regression was conducted to determine factors associated with infarction.
Results: Complete data were available for 381 of 413 patients (92%). Angiographic vasospasm was none/mild in 209 (55%) patients, moderate in 118 (31%), and severe in 54 (14%). Infarcts developed in 6 (3%) of 209 with no/mild, 12 (10%) of 118 patients with moderate, and 25 (46%) of 54 patients with severe vasospasm. Multivariate analysis found a strong association between angiographic vasospasm and cerebral infarction (OR, 9.3; 95% CI, 3.7-23.4). The significant association persisted after adjusting for admission neurological grade and aneurysm size. Method of aneurysm treatment was not associated with a significant difference in frequency of infarction.
Conclusions: A strong association exists between angiographic vasospasm and cerebral infarction. Efforts directed at further reducing angiographic vasospasm are warranted.