Meta-Analysis Comparing the Frequency of Carotid Artery Stenosis in Patients With Atrial Fibrillation and Vice Versa

Atrial fibrillation (AF) and carotid stenosis (CS) can coexist and this association has been reported to result in a higher risk of stroke than attributed to either condition alone. Here we aimed to summarize the data on the association of CS and AF. MEDLINE and Embase were searched to identify all published studies providing relevant data through February 27, 2020. Random-effects meta-analysis method was used to pool estimates of prevalence. Heterogeneity was assessed by mean I-squared statistic. Forty-eight studies were included, 20 reporting on the prevalence of carotid disease in a pooled population of 49,070 AF patients, and 28 on the prevalence of AF in a total of 2,288,265 patients with carotid disease. The pooled prevalence of CS in AF patients was 12.4% (95% confidence interval [CI] 8.7 to 16.0, I² 93%; n = 3,919), ranging from 4.4% to 24.3%. The pooled prevalence of carotid plaque was 48.4% (95% CI 35.2 to 61.7, I² = 99%; n = 4292). The prevalence of AF in patients with CS was 9.3% (95% CI 8.7 to 10.0, I² 99%; n = 2,286,518), ranging from 3.6% to 10.0%. This prevalence was much higher (p <0.001) in patients undergoing carotid artery stenting (12.7%, 95% CI 11.3 to 14.02, I² 38.3%) compared with those undergoing carotid endarterectomy (6.9%, 95% CI 8.3 to 10.4, I² 94.1%). There was no difference in AF prevalence between patients with CS, with and without previous cerebrovascular event (p >0.05). In conclusion, AF and CS frequently coexist, with about one in ten patients with AF having CS, and vice versa. In addition, nonstenotic carotid disease is present in about half of AF patients. These findings have important implications for AF screening in patients with CS, stroke prevention, and the opportunities to intervene on common risk factors.