This study is planned to evaluate the effect of left posterior pericardiotomy for the prevention of postoperative atrial fibrillation after coronary artery bypass grafting. Eligible patients will be randomized to be created or not to be created the left posterior pericardiotomy at the end of the operation, and the incidence of postoperative atrial fibrillation will be compared.

Postoperative atrial fibrillation (POAF) is a common complication after cardiac surgery, particularly after coronary artery bypass grafting (CABG), and is associated with prolonged in-hospital stay and increased adverse outcomes, including death and stroke. There is evidence that pericardial effusion can trigger the occurence of POAF. Therefore, this study is aimed to evaluate the effect of left posterior pericardiotomy for the prevention of POAF after CABG.

Patients who are planned to undergo off-pump CABG will be randomized to be created or not to be created the left posterior pericardiotomy at the end of the operation, and the incidence of postoperative atrial fibrillation will be compared as the primary outcome. Secondary outcomes will include early clinical outcomes and hospital stay.

Inclusion Criteria:

• patients who are planned to undergo coronary artery bypass grafting
• patients aged ≥19 years

Exclusion Criteria:

• patients who are planned to undergo other concomitant cardiac procedures (e.g. valve procedures, aorta procedures)
• patients who undergo coronary artery bypass grafting using cardiopulmonary bypass
• patients who are documented with paroxysmal, persistent, or permanent atrial fibrillation before operation
• patients who have a history of cardiac surgery
• patients who have a history of pericardial disease
• patients who have severe adhesion at left pleural cavity which precludes effective left posterior pericardiostomy
• patients who refuse to participate in this study

There is a plan to make individual participant data (IPD) and related data dictionaries available.

Starting 6 months after publication

IPD will be shared on reasonable request to the corresponding author.