Purpose: The goals of this study were to identify predictors of delayed cerebral infarction in aneurysmal SAH after intra-arterial (IA) vasodilator infusion and to select proper parameters for treatment success.
Methods: Forty-three patients qualified for review. Cerebral infarction was determined by DWI within 1 week of angiographic vasospasm.
Results: Infarction developed in 18 of the 43 patients (41.9%) after IA vasodilator infusion and was associated with a high degree of proximal vessel residual narrowing and angiographic cerebral circulation time (CCT) prolongation at the end of IA vasodilator infusion (p < 0.001). A high degree of proximal residual narrowing (p = 0.018; odds ratio = 1.071; 95% confidence interval [CI] 1.012-1.123) and CCT prolongation at the end of the procedure (p = 0.007; odds ratio = 2.203; 95% CI 1.254-4.232) were found to be predictors of infarction by multivariate analysis. Furthermore, receiver operating characteristic (ROC) curves showed that both variables predicted the development of infarction (proximal vessel residual narrowing, area under the ROC curve [AUC], 0.828; CCT, AUC, 0.866). When proximal vessel narrowing of >30% or a CCT of >7 s by final angiography during IA vasodilator infusion were used as a threshold, the negative predictive value for infarction was 88.9% (95% CI 65.3-98.6%), and when narrowing was >30% and CCT was >7 s, the probability of subsequent cerebral infarction was 100% (95% CI 71.7-100%).
Conclusions: Angiographic CCT and residual narrowing at the end of IA vasodilator infusion were found to predict the subsequent occurrence of cerebral infarction. The authors suggest that residual narrowing of 30% and a CCT of 7 s could be used as a minimum indicator of IA vasodilator infusion endpoints.