Background Atrial fibrillation (AF) is the most common adverse event following coronary artery bypass graft (CABG) surgery. A recent study identified chromosome 4q25 variants associated with AF in ambulatory populations. However, their role in postoperative AF is unknown. We hypothesized that genetic variants in the 4q25 chromosomal region are independently associated with postoperative AF after CABG surgery. Methods and Results Two prospectively collected cohorts of patients undergoing CABG, with or without concurrent valve, surgery at three U.S. centers. From a discovery cohort of 959 patients, clinical and genomic multivariate predictors of postoperative AF were identified by genotyping 45 SNPs encompassing the 4q25 locus. Three SNPs were then assessed in a separately-collected validation cohort of 494 patients. After adjustment for clinical predictors of postoperative AF, and multiple comparisons, rs2200733, rs13143308 and five other linked SNPs independently predicted postoperative AF in the discovery cohort. Additive ORs for the seven associated 4q25 SNPs ranged between 1.57 and 2.17 (P value 8.0 × 10-4 − 3.4 × 10-6). Association with postoperative AF were measured and replicated for rs2200733 and rs13143308 in the validation cohort. Conclusions In two independently collected cardiac surgery cohorts, non-coding SNPs within the chromosome 4q25 region are independently associated with postoperative AF after CABG surgery after adjusting for clinical covariates and multiple comparisons.

EECP treatment reduces arterial stiffness and improves wave reflection characteristics in patients with refractory angina. These changes decrease LV afterload and myocardial oxygen demand and reduce the number of angina episodes, therefore enabling patients to participate in continuous exercise programs which in turn may provide long-term benefits and sustained improved quality of life.