IMPACT OF INTRAOPERATIVE MICRO-HEMODYNAMIC FLUCTUATIONS ON EARLY GRAFT PATENCY AFTER CORONARY ARTERY BYPASS SURGERY

Abstract

Background: Coronary artery bypass grafting (CABG) remains an effective treatment for advanced coronary artery disease; however, early graft dysfunction continues to affect postoperative outcomes. Current intraoperative graft assessment methods mainly evaluate graft performance after completion of anastomosis, while the potential influence of continuous intraoperative hemodynamic fluctuations remains insufficiently explored.

Objective: This study aimed to evaluate the association between minute-to-minute intraoperative micro-hemodynamic variability and early graft patency following CABG.

Study Type: Prospective observational cohort study

Methods: A prospective observational cohort study was conducted at a tertiary cardiac care hospital in Peshawar, Pakistan. Adult patients undergoing isolated CABG were included. Continuous arterial pressure recordings were collected throughout the surgical procedure, and intraoperative hemodynamic variability was assessed using mean arterial pressure (MAP) fluctuations, frequency of hypotensive episodes, and cumulative duration of reduced perfusion pressure. After completion of grafting, transit-time flow measurement (TTFM) was performed to evaluate graft function using mean graft flow, pulsatility index, and diastolic filling percentage. Associations between intraoperative hemodynamic parameters and early graft dysfunction were analyzed using appropriate statistical methods.

Results: A total of 120 patients were included in the analysis. Patients with early graft dysfunction demonstrated significantly higher MAP variability compared with those with satisfactory graft function (10.1 ± 2.8 vs. 6.3 ± 2.2 mmHg, p < 0.001). Greater hemodynamic fluctuation was associated with reduced mean graft flow, increased pulsatility index, and lower diastolic filling percentage. After adjustment for clinical and operative variables, increased MAP variability remained independently associated with early graft dysfunction (adjusted OR 1.18, 95% CI 1.06–1.32, p = 0.003).

Conclusion: Intraoperative micro-hemodynamic instability may represent an important and potentially modifiable factor influencing early graft performance after CABG. Continuous assessment of blood pressure variability combined with routine graft flow evaluation may improve identification of patients at risk of early graft dysfunction and support more individualized intraoperative management strategies.