Neurological outcomes of transcatheter aortic valve implantation with or without cerebral embolic protection devices: A meta-analysis

Introduction: Cerebral embolic protection devices (CEPDs) are designed to prevent embolization of debris during transcatheter aortic valve implantation (TAVI). Current evidence from randomized clinical trials (RCTs) and observational studies is controversial. Aims: The purpose of this meta-analysis was to study the influence of CEPDs on stroke, silent ischemic lesions and neurocognitive function. Methods: A systematic search was conducted including RCTs or adjusted observational studies comparing TAVI with or without CEPDs. Pooled odds ratios, risk ratios or standardized mean differences with 95% confidence intervals were calculated using the inverse of variance method. Risk of bias sensitivity analyses and meta regression for CEPD type were also conducted. Results: Five RCTs and five adjusted observational studies were included (n=159,865). Mean age of the patients was 81.1 (SD 1.04) years in CEPDs and 81 (SD 1.86) in non-CEPD. The overall quality of evidence using the GRADE system for each endpoint was low to very low, mainly due to serious risk of bias, inconsistency and imprecision. Random effects meta-analysis detected no significant differences between CEPD and non-CEPD (OR= 0.74; 95% CI 0.51-1.07; P=0.105; I-2=82.1%) for 30-day stroke. This finding was consistent in meta regression for CEPD type and subgroup analyses by study type and CEPD type. No significant differences between groups were observed in cerebral DW-MRI assessment and neurocognitive function evaluation. Conclusion: In the present meta- analysis of five RCTs and five adjusted observational studies, the use of a CEPD during TAVI was not associated with a significant benefit on 30- day stroke, total lesion volume per patient, number of ischemic lesions per patient and neurocognitive function assessments.