Predictors of Delayed Cerebral Ischemia After Aneurysmal Subarachnoid Hemorrhage: A Cardiac Focus

Abstract

Myocardial injury after aneurysmal subarachnoid hemorrhage (aSAH) is associated with poor outcomes. Delayed cerebral ischemia (DCI) is also a complication of aSAH. We sought to determine whether (1) DCI could be predicted by demographics, aSAH severity/aneurysm location, or aSAH-associated myocardial injury (SAHMI), and (2) DCI is associated with increased mortality after aSAH. Prospective longitudinal study of 149 aSAH subjects with definitive DCI evaluation, age 18-75 years, Hunt and Hess (HH) ≥ 3, and/or Fisher ≥ 2, and admitted to the Neurovascular ICU. DCI was defined by the presence of neurological deterioration accompanied by evidence of abnormal cerebral blood flow. Subjects were 48% DCI(+) and 52% DCI(-). DCI(+) subjects had more severe aSAH [HH (P = 0.002), Fisher (P = 0.004), admission Glasgow Coma Scale (P = 0.018)]. More DCI(+) subjects had pulmonary congestion than DCI(-) subjects (63 vs. 39%, P = 0.003). On echocardiogram, cardiac output (CO, liters per minute [LPM]) was significantly higher in DCI(+) than in DCI(-) subjects (6 ± 2 vs. 5 ± 1 LPM; P = 0.015). Multivariate analysis identified CO and Fisher grade as independent predictors of DCI (P = 0.02, 0.019). For each 1 LPM increase in CO, the odds of DCI increased by 1.5 (95% CI: 1.1-2.1). Fisher grade 4 increased the odds of DCI by 6.5 compared to Fisher grade 2 (95% CI: 1.6-25.8). After controlling for Fisher grade, CO remained an independent predictor of DCI (P = 0.02). Three-month mortality rate was not significantly different between DCI groups, P = 0.786. Elevated CO and Fisher grade are predictors of DCI after aSAH. However, prevention of DCI may not decrease mortality.