Association of pre-operative N-terminal pro–B-type natriuretic peptide level on early outcomes of off-pump coronary artery bypass grafting

Background: Off-pump coronary artery bypass grafting (OPCABG) is considered safer than traditional on-pump coronary artery bypass grafting (CABG) due to its avoidance of a heart-lung machine. This study was aimed to evaluate role of pre-operative N-terminal pro–B-type natriuretic peptide (NT-pro-BNP) level in patients undergoing OPCABG. Methods: A comparative cross-sectional study was carried out in the Department of Cardiac Surgery, National Institute of Cardiovascular Diseases (NICVD) from January 2022 to December 2023. Continuous data were analyzed by Student’s t-test and categorical data by Chi-square and Fisher’s exact test. A p≤0.05 was considered statistically significant. Results: Our study shows that the incidence of arrhythmia was significantly higher in group A (NT-pro-BNP≥348 pg/ml) than group B (NT-pro-BNP<348 pg/ml). Post-operative arrhythmia occurred only in 9 (18%) patients in group B but in group A 19 (38%) patients developed arrhythmia (p<0.001). Incidence of postoperative low cardiac output syndrome (LCOS) was significantly higher in group A (NT-pro-BNP≥348 pg/ml). Group A patients experienced notably extended mechanical ventilation time (9.77±4.87 versus 6.39±2.13 hours; p<0.001), prolonged ICU stay (7.01±5.12 versus 4.87±2.98 days; p=0.005), and extended postoperative hospital stay (12.56±5.40 versus 7.08±4.15 days; p<0.001) compared to group B. No significant difference was observed between the two groups in regards to demographics and associated risk factors. Conclusion: Our current study illustrated that elevated preoperative NT-pro-BNP levels (≥348) were linked to an increased occurrence of postoperative complications such as low cardiac output syndrome and arrhythmia.