Ligament of Marshall transection during coronary artery bypass grafting and postoperative atrial fibrillation: early results of a pilot randomized study

Aim. To evaluate the impact of Marshall ligament cutting off on the incidence of atrial fibrillation (AF) within 1 month after coronary artery bypass grafting (CABG). Methods. A double-blind, randomized, single-center clinical trial included 60 patients; 30 patients were allocated to the Marshall ligament cutting off group (main group), and 30 patients to the group without Marshall ligament cutting off (control group). The groups did not differ in baseline clinical and demographic parameters. The primary endpoint was the occurrence of AF within 28 days after CABG. Logistic regression was performed to identify efficacy factors. Results. Postoperative AF developed in 9 patients: 7 patients in the control group and 2 patients in the main group. The statistical model revealed two independent factors that significantly reduced the risk of postoperative AF: performing the surgery without cardiopulmonary bypass (off-pump) and Marshall ligament cutting off (p=0.030 and p=0.048, respectively). The logistic regression model demonstrated excellent predictive ability and high patient classification accuracy; sensitivity was 93.8%, specificity was 62.5% at a cutoff of 0.5. The area under the ROC curve (AUC=0.898) indicates the model’s excellent ability to distinguish between patients with and without postoperative atrial fibrillation. Conclusion. Marshall ligament transection during off-pump CABG prevents the development of postoperative atrial fibrillation.