SYNTAX score affects LIMA graft flow dynamics in coronary artery bypass surgery

İngilizce (OpenAlex)

Coronary artery bypass grafting (CABG) is indicated for myocardial revascularization in patients with multivessel coronary artery disease or left main coronary artery disease, and its long-term success is largely determined by graft patency.The choice of graft conduits, surgical technique, and patient-related factors are key determinants of sustained graft function.[1] With a reported incidence of 5-11%, perioperative graft failure is associated with serious adverse outcomes, including myocardial infarction, arrhythmias, and death; the most severe complications are linked to failure of the left internal mammary artery (LIMA) graft to the left anterior descending (LAD) artery.[2][3][4] Transit time flow (TTF) measurement enables intraoperative assessment of graft flow characteristics and provides surgeons with quantitative information regarding graft patency and anastomotic quality.[5,6] Intraoperative graft flow assessment using TTF is recommended as a class IIa indication in current myocardial revascularization guidelines.[7] The use of TTF allows surgeons to objectively document graft quality and to revise anastomoses intraoperatively when flow parameters are deemed unsatisfactory.The SYNTAX score is an anatomical scoring system widely used to guide decision-making regarding the optimal revascularization strategy.[8] Although it has also been evaluated for its ability to predict postoperative outcomes, its prognostic value in this context has been reported to be limited.[9,10] The SYNTAX II score incorporates seven additional clinical variables alongside the anatomical SYNTAX score and has demonstrated a stronger association with mortality and graft patency.[11,12] While the SYNTAX score reflects the extent and severity of coronary atherosclerotic disease, the SYNTAX II score integrates this anatomical burden with Background: Intraoperative transit time flow (TTF) measurement provides quantitative information regarding graft patency and anastomotic quality.However, limited data exist on the relationship between SYNTAX scores and intraoperative graft flow dynamics during coronary artery bypass grafting (CABG).This study aimed to evaluate the predictive value of SYNTAX scores for intraoperative graft flow parameters, as assessed by TTF measurements of the left internal mammary artery (LIMA) grafted to the left anterior descending (LAD) artery.Methods: Patients with critical LAD disease who underwent CABG at a single tertiary referral center between February and October 2019 were prospectively evaluated.For each patient, the SYNTAX score, SYNTAX II score, and the LAD-specific contribution to the SYNTAX score (LAD-SYNTAX) were calculated.Correlations between these scores and TTF parameters-including mean graft flow (MGF), diastolic flow (DF), and pulsatility index (PI)-were analyzed.Results: The SYNTAX score demonstrated a negative correlation with MGF (r =-0.118, p=0.313) and DF (r =-0.026, p=0.828), and a positive correlation with PI (r =0.131, p=0.264).Similarly, the SYNTAX II score showed negative correlations with MGF (r=-0.040,p=0.735) and DF (r=-0.246,p=0.037), and a positive correlation with PI (r=0.168,p=0.149).Consistent trends were observed with LAD-SYNTAX, with MGF and DF showing negative correlations and PI showing a positive correlation; notably, the correlation between LAD-SYNTAX and MGF was statistically significant (r=-0.288,p=0.012).Conclusion: SYNTAX scores are associated with intraoperative TTF measurements of the LIMA-LAD graft.These findings suggest that both the atherosclerotic burden of the target vessel and patient-specific factors may influence LIMA graft flow dynamics during CABG.