Cerebral hyperperfusion syndrome and intracranial hemorrhage after carotid endarterectomy or carotid stenting: A meta-analysis

Introduction: Cerebral hyperperfusion syndrome (CHS) and intracranial hemorrhage (ICH) after carotid revascularization have been associated with significant morbidity and mortality, although pooled data comparing these outcomes between open and endovascular treatment are lacking. Aim of this meta-analysis is to compare CHS and ICH risk between carotid endarterectomy (CEA) and carotid angioplasty with stenting (CAS). Methods: A systematic literature review was conducted conforming to established criteria, in order to identify eligible articles published prior to February 2017. Eligible studies compared CHS and/or ICH between patients undergoing CEA and CAS. Other outcomes evaluated in this review included stroke and death due to ICH. Outcome risks are presented as odds ratios (OR) and 95% confidence intervals (CI). Results: Overall, 6 studies (5 studies reporting on CHS and 4 studies reporting on ICH) included 236,537 procedures (218,144 CEA; 18,393 CAS) in total. CEA was associated with a higher risk for CHS compared to CAS (pooled OR = 1.432 [95% CI = 1.078-1901]; P = 0.015), although this difference was generated mainly from older studies (prior to 2012). However, no difference was found regarding ICH risk between the two methods (pooled OR = 0.544 [95% CI = 0.111-2.658]; P = 0.452). Regarding stroke incidence, no difference was found between the two methods as well, although this resulted mainly from studies with a higher volume of CAS procedures (pooled OR = 0.964 [95% CI = 0.741-1.252]; P = 0.833). Finally, death rate was significantly higher among patients with ICH compared to patients without ICH (pooled OR = 386.977 [95% CI = 246.746-606.906]; P < 0.0001). Pooled data were not adequate to calculate potential risk factors for CHS/ICH after CEA compared to CAS. Conclusions: CEA seems to be associated with a higher risk for CHS compared to CAS, although this difference was generated mainly from older studies. However, there seems to be no difference regarding ICH risk between the two methods, with ICH being associated with a significantly higher risk for death.