A Systematic Review and Meta-Analysis of Transcarotid Artery Revascularization with Dynamic Flow Reversal Versus Transfemoral Carotid Artery Stenting and Carotid Endarterectomy

Background: Transfemoral carotid artery stenting (TFCAS) was introduced as a less invasive option for carotid revascularization in patients at high risk for complications from carotid endarterectomy (CEA). The increased perioperative stroke and death risk of TFCAS has however prevented TFCAS from widespread acceptance as an alternative to CEA in high-risk patients. Recent research suggests that transcarotid artery revascularization (TCAR) may be associated with a low stroke and death risk and potentially meet the needs of patients at high surgical risk. We aimed to estimate the 30-day risk of stroke or death of TCAR and compare it to TFCAS and CEA. Methods: We searched PubMed, Cochrane, Embase, and Scopus for studies of patients treated with TCAR. Meta-analysis was conducted when appropriate. A logistic-normal random-effects model with logit transformation was used to estimate the pooled event rates after TCAR. Pooled Mantel-Haenszel odds ratios (ORs) of events comparing TCAR to TFCAS and CEA were calculated using a fixed-effects model. Heterogeneity among studies was quantified with the chi-squared statistic of the likelihood ratio (LR) test that compares the random-effects and fixed-effects models. Results: Nine nonrandomized studies evaluating 4012 patients who underwent TCAR were included. The overall 30-day risks after TCAR were stroke/death, 1.89% (95% confidence interval [CI]: 1.50, 2.37); stroke, 1.34% (95% CI: 1.02,1.75); death, 0.76% (95% CI: 0.56, 1.08); myocardial infarction (MI), 0.60% (95% CI: 0.23, 1.59); stroke/death/MI, 2.20% (95% CI: 1.31, 3.69); cranial nerve injury (CNI), 0.31% (95% CI: 0.12, 0.83). The failure rate of TCAR was 1.27% (95% CI: 0.32, 4.92). Two nonrandomized studies suggested that TCAR was associated with lower risk of stroke and death as compared with TFCAS (1.33% vs. 2.55%, OR: 0.52, 95% CI: 0.36, 0.74 and 0.76% vs. 1.46%, OR: 0.52, 95% CI: 0.32, 0.84, respectively). Four nonrandomized studies suggested that TCAR was associated with a lower risk of CNI (0.54% and 1.84%, OR: 0.52, 95% CI: 0.36, 0.74) than CEA, but no statistically significant difference in the 30-day risk of stroke, stroke/death, or stroke/death/MI. Conclusions: Among patients undergoing TCAR with dynamic flow reversal for carotid stenosis the 30-day risk of stroke or death was low. The perioperative stroke/death rate of TCAR was similar to that of CEA while CNI risk was lower. Larger prospective studies are needed to account for confounding factors and provide higher certainty.