Impact of Ligament of Marshall Resection on Atrial Fibrillation Occurrence in Patients Undergoing Coronary Artery Bypass Grafting: A Randomized Controlled Trial

NCT07492901 | Completed DMC

• 1 other identifier: 04-2025-300780
• Study Type: interventional
• Target: 220
• Locations: 1 country
• Sites: 2

Brief Summary

Background: 20-40% of patients with ischemic heart disease managed with coronary artery bypass grafting (CABG) surgeries face the risk of postoperative atrial fibrillation (POAF), which is a known hazardous outcome. Being a well-known arrhythmogenic pathway, surgical excision of the ligament of Marshall may, theoretically, lower the incidence of POAF. Aim: In this study, we aimed to assess the safety and efficacy of prophylactic LoM resection in preventing POAF after on-pump CABG (ON-CAB.). Methods: 220 patients at elevated risk for POAF undergoing elective ON-CAB were randomized to receive either standard CABG alone (n = 110) or adjunctive LoM resection (n = 110) in this multicenter, randomized, assessor- and patient-blinded study with unblinded surgeons. ECG-verified POAF occurring within seven days was the primary outcome. Mortality, use of resources, and pharmaceutical therapy were secondary outcomes.

Conditions

Post Operative Arrythmia

Keywords

surgical ablation of ligament of marshall

Outcome Measures

Primary Outcomes (1)

• Incidence of postoperative atrial fibrillation (POAF)

  Occurrence of any episode of atrial fibrillation or atrial flutter lasting ≥30 seconds, confirmed by continuous telemetry monitoring or 12-lead electrocardiogram, adjudicated by blinded cardiologists. Both symptomatic and asymptomatic episodes were included.

  Within 7 days after coronary artery bypass grafting

Secondary Outcomes (6)

• In-hospital all-cause mortality

  During index hospitalization (up to 30 days)

• Major postoperative complications

  Within 30 days postoperatively

• Use of amiodarone therapy

  Within 7 days postoperatively

• Duration of inotropic support

  During ICU stay

• Length of intensive care unit (ICU) stay

  During index hospitalization

Other Outcomes (1)

• Operative and procedural characteristics

  Intraoperative period

Study Arms (2)

standard CABG alone

ACTIVE COMPARATOR

this group underwent CABG only

Procedure: A standard on-pump coronary artery bypass grafting (ON-CAB)

adjunctive LoM resection

ACTIVE COMPARATOR

Procedure: adjunctive LoM resection

Interventions

A standard on-pump coronary artery bypass grafting (ON-CAB) PROCEDURE

A standard on-pump coronary artery bypass grafting (ON-CAB) technique was used. All operations were performed through a median sternotomy. The left internal mammary artery was harvested (commonly pedicled unless skeletonization was indicated as in diabetic patients), and additional conduits, including the radial artery or saphenous vein, were obtained when required. Systemic anticoagulation was achieved using intravenous heparin to maintain an activated clotting time exceeding 480 seconds. Cardiopulmonary bypass (CPB) was established via ascending aortic cannulation and two-stage venous cannulation of the right atrium. Moderate systemic hypothermia (32-34°C) was maintained throughout CPB, with alpha-stat pH management. Myocardial protection was provided using antegrade cold blood cardioplegia with a 4:1 blood-to-crystalloid ratio, administered through the aortic root, with repeated doses every 20 minutes or following completion of each distal anastomosis. Distal coronar

standard CABG alone

adjunctive LoM resection PROCEDURE

After gentle mobilization of the left atrial appendage, the left atrial ridge was exposed, allowing clear visualization of the ligament of Marshall (LoM) as a fibrofatty bundle containing myocardial fibers, autonomic nerve fibers, and small vascular structures. Careful sharp and blunt dissection was performed to free the LoM from surrounding tissues, with meticulous attention to avoid injury to adjacent structures, particularly the left circumflex coronary artery and the left pulmonary veins. Following complete isolation, the proximal and distal ends of the LoM were secured either by ligation with 5-0 polypropylene sutures or by application of two medium hemoclips placed proximally near its insertion into the coronary sinus region and distally near the left atrial appendage. The intervening segment was then excised completely, ensuring no residual LoM tissue remained.

adjunctive LoM resection

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Adults aged ≥18 years.
• Scheduled for elective on-pump coronary artery bypass grafting (CABG).
• Diagnosed with multivessel coronary artery disease or left main disease requiring surgical revascularization according to current guidelines.
• Classified as high risk for postoperative atrial fibrillation, defined as the presence of at least two of the following:
• Age ≥65 years
• Left atrial enlargement (anteroposterior diameter \>40 mm on transthoracic echocardiography)
• History of paroxysmal atrial fibrillation not requiring long-term anticoagulation
• Chronic obstructive pulmonary disease requiring regular pharmacological therapy
• Ability to provide written informed consent.
• \*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*

You may not qualify if:

• Preoperative atrial fibrillation requiring active treatment or long-term anticoagulation.
• History of previous cardiac surgery.
• Severe left ventricular systolic dysfunction (ejection fraction \<30%).
• Emergency or urgent CABG.
• Concomitant cardiac procedures (e.g., valve surgery, surgical ablation for atrial fibrillation).
• Contraindications to anticoagulation or antiarrhythmic therapy.
• Inability or unwillingness to provide informed consent.

Sponsors & Collaborators

• Kasr El Aini Hospital: lead

Study Sites (2)

Kasr Alainy

Cairo, 02, Egypt

Location

Cairo University

Cairo, Egypt

Location

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: PREVENTION
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Associate Professor of Cardiothoracic surgery

Study Record Dates

• First Submitted: March 4, 2026
• First Posted: March 25, 2026
• Study Start: January 11, 2024
• Primary Completion: November 11, 2025
• Study Completion: November 30, 2025
• Last Updated: March 25, 2026

Record last verified: 2026-03

Data Sharing

• IPD Sharing: Will not share

Locations

EG (2)