Abstract Body (Do not enter title and authors here): Background
Postoperative atrial fibrillation (POAF) is commonly seen in patients undergoing coronary artery bypass grafting (CABG), increasing the risk of both short-term and long-term clinical adverse events. This study aimed to evaluate the effectiveness of partial cardiac denervation, which is achieved by cutting off the ligament of Marshall (LOM) and resecting the fat pad along the Waterston groove, on the prevention of POAF after CABG.
Methods
In this single-center randomized controlled study, patients planned for isolated CABG were recruited during August 2022 and December 2023, then randomized into the intervention group (CABG + partial cardiac denervation) and the control group (CABG only) in a 1:1 pattern. All the participants were continuously monitored for the incidence of POAF through electrophysiologic device till day 6 after the operation, and invited to follow-up visits 30 days after discharge. The primary endpoint was the incidence of POAF, while the secondary endpoints were the safety and economics outcomes.
Results
A total of 430 patients were enrolled (215 in the intervention vs. 215 in the control). The mean age was 61.9 ± 7.8 years, and 18.4% of them were female. Baseline characteristics were well balanced after ramdomizaiton. All participants underwent successful CABG and each one in the intervention group received scheduled partial cardiac denervation procedure. Compared with the control group, the 6-day incidence of POAF was significantly lower in the intervention group (18.1% vs. 31.6%, p=0.001). The time-to-event analysis also showed a significant reduction in the occurrence of POAF in the intervention group (hazard ratio: 0.53, 95% confidence interval: 0.36 to 0.79, p = 0.002). Similar effect was observed in the subgroup analysis. Safety assessments showed no difference between the two groups, for the incidence of need for blood transfusion, transferring to on-pump CABG, re-operation for postoperative bleeding, delayed epicardial effusion, critical arrhythmias other than atrial fibrillation and major adverse events in the 30-day follow up. The economic assessments showed that postoperative medical cost was reduced in the intervention group (p=0.050).
Conclusions
Partial cardiac denervation through cutting off the LOM and resecting the fat pad along the Waterston groove, was an effective and safe procedure to reduce the occurrence of POAF after isolated CABG.