Effect of Clinical and Genetic Factors on the Development of Postoperative Atrial Fibrillation After Coronary Artery Bypass Grafting (CABG) in Egyptian Patients Receiving Beta-Blockers.

Purpose: Prophylactic beta-blockers are recommended to prevent postoperative atrial fibrillation (POAF) after coronary artery bypass grafting (CABG). Polymorphisms in the beta-1 adrenergic receptor (ADRB1) and G protein-coupled receptor kinase 5 (GRK5) genes are associated with variable responses to beta-blockers. The aim of this study was to determine the clinical and genetic factors that influence the response to beta-blockers for POAF prophylaxis after CABG.

Methods: Patients undergoing isolated CABG and receiving prophylactic beta-blockers (n = 249) were prospectively recruited and followed up for 6 postoperative days. Genotyping of ADRB1 rs1801253, and 3 GRK5 SNPs (rs3740563, rs10787959, and rs17098707) was performed.

Results: Of the 249 patients, 52 patients (20.8%) experienced POAF. Age, hypertension, vasopressor use, calculated POAF risk score, GRK5 rs2230345 T-allele, and GRK5 rs3740563 A-allele were associated with POAF despite beta-blocker prophylaxis. The multivariate analysis revealed that age [odds ratio (OR) 1.06, 95% CI 1.02-1.11, p = 0.003] and GRK5 rs2230345 T-allele [OR 2.81, 95% CI 1.39-5.67, p = 0.004] were independent predictors of POAF after CABG despite beta-blocker prophylaxis.

Conclusion: GRK5 rs2230345 T-allele carriers were less responsive than AA genotype carriers to prophylactic beta-blockers for the prevention of POAF after CABG. The study was registered on http://clinicaltrials.gov in March 2019, with trial registration number (TRN): NCT03871647.