Intracranial Atherosclerosis Increases the Risk of Postoperative Stroke After Cardiac Surgery: A Review and Meta-Analysis.

Abstract

Postoperative stroke is a devastating complication of cardiac surgery with high morbidity, mortality, and health care cost. Extracranial carotid atherosclerosis (ECAS) is a known risk factor for stroke; however, the impact of intracranial atherosclerosis (ICAS) remains unclear. To our knowledge, this is the first literature review of ICAS in cardiac surgery. We aimed to assess the prevalence, association with postoperative stroke, and perioperative management of ICAS in cardiac surgery. A search was performed to identify studies reporting rates of ICAS and stroke after cardiac surgery. Data extraction and primary outcomes for meta-analysis included the prevalence of preoperative ICAS and the association between ICAS and stroke. Risk ratios (RRs) and 95% confidence intervals (CIs) were pooled by random-effects modelling. Seventeen studies were reviewed and seven were included in the meta-analysis, comprising 4,936 patients. Prevalence of intracranial atherosclerosis (ICAS) among cardiac surgery patients was 21% (95% CI 13%-32%). Patients with ICAS were more likely to develop postoperative stroke (RR 3.61; 95% CI 2.30-5.67; p<0.001). ICAS was more closely associated with stroke than ECAS. Preoperative brain perfusion single-photon emission computed tomography with acetazolamide challenge, staged intracerebral revascularisation, or conversion to off-pump coronary artery bypass grafting are described management options for ICAS. Patients with ICAS are 3.61 times more likely to develop stroke after cardiac surgery. Known predictors for ICAS can be used to develop risk stratification screening tools. Further research with diverse cohorts is required to develop evidence-based guidelines for screening and management of ICAS in cardiac surgery.