Impact of Visceral Adiposity on Postoperative Atrial Fibrillation After CABG

Impact of Visceral Adiposity on Postoperative Atrial Fibrillation After Coronary Artery Bypass Grafting (CABG): A Prospective Observational Study

Obesity has become a major public health problem in both developed and developing countries, with a continuous increase particularly since the 1980s. Moreover, it is a well-established metabolic risk factor for diabetes mellitus, hypertension, and various types of cancer, as well as cardiovascular diseases such as heart failure and coronary artery disease. Body mass index (BMI) is calculated by dividing body weight in kilograms by the square of height in meters and is widely used as an indicator of obesity. However, BMI does not quantitatively reflect body fat distribution and fails to account for components such as skeletal muscle and bone mass. Therefore, interest in assessing body fat distribution has increased, and in recent years, studies evaluating the correlation between anthropometric, biochemical, and anatomical measurements and clinical outcomes have become more frequent. In particular, it is acknowledged that abdominal obesity cannot be accurately represented by BMI alone and is primarily associated with visceral adipose tissue (VAT). The aim of this study is to evaluate the association between preoperative visceral and subcutaneous adipose tissue measurements (VAT and SAT), assessed by ultrasonography in patients scheduled for open-heart surgery, and the development of postoperative atrial fibrillation.

Inclusion Criteria:

• Elective isolated coronary artery bypass graft surgery (on-pump)
• Age ≥18 years, planned prospectively in 300 patients

Exclusion Criteria:

• Patients requiring urgent or emergency surgery
• Off-pump coronary artery bypass graft surgery
• Surgeries other than isolated coronary artery bypass graft
• Patients in whom abdominal ultrasound measurement cannot be performed (e.g., due to severe deformity, wounds, edema)
• Active malignancy
• eGFR <30 mL/min
• Advanced-stage chronic obstructive pulmonary disease (COPD)
• Preoperative atrial fibrillation or atrial flutter
• Patients who do not provide written informed consent for the study