Introduction: Medical, surgical, and endovascular care for carotid disease has continued to evolve. We aimed to review and analyze the most recent studies comparing short and longterm complications of CEA and CAS in asymptomatic patients with extracranial carotid artery stenosis.
Methods: Two recent major clinical trials involving asymptomatic carotid stenosis (i.e. ACT I and CREST) were included. From CREST, data for patients with asymptomatic stenosis were extracted and included in this metaanalysis. Outcome measures included in the analysis were: stroke, myocardial infarction (MI), and death or stroke, both individually and as a composite outcome as defined in the trials. Methodological quality was assessed using the Cochrane Collaboration’s tool for assessing risk of bias. A metaanalysis was performed on comparable outcomes at the same timepoints using RevMan ver 5.3 software. Risk ratios (RRs) with 95 % confidence interval (CI)s were calculated using the MantelHaenszel method with fixedeffect models. Heterogeneity was assessed by I2 and Cochran Q tests.
Results: ACT I showed a lower methodological quality, having a higher risk of attrition bias and failing to report blinding of outcome assessment. There was no significant difference in the composite outcome of death, stroke (ipsilateral or contralateral, major or minor), or MI during the periprocedural period (p=0.70). No heterogeneity was observed in the analyses (I2= 0). During the periprocedural period, CAS had a significantly higher rate of stroke alone than CEA (p=0.05), and trend towards higher stroke or death than CEA (p=0.07). In the postprocedural period, the two treatments did not have different rates for the composite of death, stroke or MI at 5 years.
Conclusions: Both CREST and ACT I individually failed to show any differences between CEA and CAS in asymptomatic patients (CREST was not powered to determine such a difference in asymptomatic patients a priori). However, their combined metaanalysis demonstrates a higher risk of periprocedural stroke after CAS than CEA in asymptomatic extracranial ICA stenosis. It is unclear whether further evolution in endovascular techniques may change this, and whether any intervention is superior to medical therapy in asymptomatic carotid stenosis.
Patient Care: Patients selected for intervention should preferentially undergo CEA rather than CAS due to a lower risk of periprocedural stroke.
Learning Objectives: Current trials (such as CREST-2) are underway to determine whether any intervention is warranted in asymptomatic carotid stenosis. Until then, patients selected for intervention should preferentially undergo CEA rather than CAS due to a lower risk of periprocedural stroke.