Prognostic impact of incomplete revascularization in coronary artery bypass grafting: Association between residual SYNTAX score, magnetic resonance imaging, myocardial injury, and cardiovascular events

Cardiac biomarkers are frequently released after revascularization. Incomplete revascularization may be a potential mechanism of action. This study aimed to investigate the relationship between the completeness of revascularization, quantified by the residual SYNTAX score (rSS), and myocardial injury, infarction, and cardiac events after coronary artery bypass grafting. This study included patients with stable coronary artery disease who underwent surgery. Troponin levels, cardiac magnetic resonance, and late gadolinium enhancement were assessed before and after the procedure. The baseline SYNTAX score was determined from the angiograms, and the rSS was measured based on the operative report for each patient after the procedure. Of the 136 surgical patients studied, no significant correlations were found between the rSS and median peak troponin level (R = 0.06, P = .47). The rSS was not a predictor of myocardial infarction, as assessed by late gadolinium enhancement (odds ratio [OR] 0.96, 95% confidence interval [CI] 0.86-1.03; P = .51) and release of troponin higher than the median (OR 1.00, 95% CI 0.92-1.08; P = .93). After multivariate analysis in a model including variables, only cardiopulmonary bypass time was a significant predictor of troponin peak release, which was higher than the median (OR 1.01, 95% CI 1.002-1.019; P = .01). During the 5-year follow-up, the incomplete revascularization group had more major cardiovascular events than the complete revascularization group (rSS = 0) (P log-rank = .006, adjusted hazard ratio = 11.32; P = .001). Myocardial injury and infarction were not significantly associated with the completeness of revascularization. However, the rSS had a prognostic impact during follow-up for cardiovascular events.