PREOPERATIVE LEFT ATRIAL STRAIN AS A PREDICTOR OF POSTOPERATIVE ATRIAL FIBRILLATION IN PATIENTS UNDERGOING CORONARY ARTERY BYPASS GRAFTING

Abstract

Objectives: To determine whether preoperative left atrial reservoir strain (LASr) was associated with postoperative atrial fibrillation (POAF) in patients undergoing coronary artery bypass grafting (CABG). Study Design and Setting: Prospective observational study conducted at Punjab Institute of Cardiology over six months, from December 2025 to May 2026. Methodology: Eighty adult patients undergoing elective isolated CABG were enrolled. Preoperative clinical assessment, electrocardiography, and conventional echocardiography were performed. Left atrial reservoir strain was assessed using two-dimensional speckle-tracking echocardiography. Patients were continuously monitored postoperatively for new-onset AF. Perioperative beta-blocker and amiodarone use was documented. Patients were categorized into POAF and non-POAF groups. Statistical analysis was performed using SPSS version 27. Logistic regression was used to identify independent predictors of POAF. Results: POAF occurred in 25 (31.3%) patients. Patients who developed POAF had significantly lower preoperative LASr than those without POAF (21.8±4.7% vs. 28.9±5.3%; p<0.001). Left atrial volume index was also higher in the POAF group (33.2±6.7 vs. 28.0±6.1 mL/m²; p=0.002). On multivariable analysis, lower LASr independently predicted POAF (OR=0.82, 95% CI: 0.73–0.92; p=0.001), along with age and left atrial volume index. Conclusions: Reduced preoperative LASr was independently associated with POAF following CABG. Preoperative left atrial strain assessment may provide additional risk stratification for patients undergoing CABG.