The Correlation between the Severity of Coronary Artery Disease and Coronary Collateral Circulation and Atrial Fibrillation after Coronary Artery Bypass Surgery: A Cross-Sectional Study

Background: Post-Operative Atrial Fibrillation (POAF) is the most common cardiac arrhythmia, which occurs in nearly 15 - 40% of patients after Coronary Artery Bypass Graft (CABG) surgery. However, the exact mechanism of POAF development is unclear.
Objectives: The present study aimed to investigate whether ischemic severity and preoperative coronary collateral circulation grade were associated with the development of POAF.
Methods: This cross-sectional, observational study assessed 246 patients who underwent CABG surgery from September 2017 to September 2019. The patients were divided into two groups according to the development of POAF; 51 patients in the POAF group and 195 patients in the group without POAF. Clinical variables were recorded. Additionally, coronary collateral circulation and the severity of coronary artery disease were assessed and recorded for each patient according to Rentrop classification and Gensini score.
Results: POAF was observed in 51 patients (20.7%). The results of multivariate analysis showed that chronic obstructive pulmonary disease (OR = 5.4, CI = 1.17 - 25.1, P = 0.03) was the independent predictor of POAF development. However, no significant association was found between the development of POAF and coronary collateral circulation (OR = 0.82, CI = 0.44 - 1.52, P = 0.54) and severity of coronary artery disease (OR = 0.98, CI = 0.42 - 2.29, P = 0.97). Furthermore, the coronary collateral circulation status was poorer in patients with the history of chronic obstructive pulmonary disease who developed POAF.
Conclusions: Preoperative coronary collateral circulation and severity of coronary artery disease were not associated with the development of POAF. However, patients with the history of chronic obstructive pulmonary disease who developed POAF had poorer coronary collateral circulation, indicating that hypoxia might play a role in the development of POAF.