The role of SYNTAX score in decision-making for preoperative carotid artery screening in patients undergoing coronary artery bypass surgery.

Background: The coexistence of coronary artery disease (CAD) in patients undergoing coronary artery bypass surgery (CABG) is a risk factor for stroke and death. The aim of this study is to evaluate the potential of the SYNTAX score (SXscore) for predicting carotid stenosis in patients undergoing CABG.

Methods: We retrospectively reviewed 291 patients (225 males, mean age 60.5 ± 8.5 years) who underwent CABG in a single center in 2014 and were screened for carotid artery preoperatively. The total SXscore was obtained by scoring every luminal narrowing greater than 50% in coronary vessels larger than 1.5 mm using the SXscore algorithm. Correlations between the severity of carotid stenosis and SXscore were analyzed.

Results: As the degree of carotid artery stenosis increases (≤%50; ≥%50 vs ≥%70), the mean SXscore (19.06 ± 7.72, P > 0,05; 28.40 ± 6.89, P < 0,01; 31.02 ± 7.04, P < 0.01, respectively) were found to increase. Receiver operating characteristic analysis revealed a cut-off point of 27 or more in SXscore according to the presence of carotid stenosis greater than or equal to %70. The risk of existence of significant carotid stenosis was 58-fold greater in cases with SXscore greater than or equal to 27. In cases with SXscore greater than or equal to 27, the risk of existence of significant carotid stenosis was 58-fold greater with a confidence interval of 95%. Moreover, the presence of left main CAD was associated with the severity of carotid stenosis (<50% carotid stenosis, P > 0.05; ≥%50, P = 0.001; and ≥70, P = 0.001).

Conclusion: This study suggests that the presence of left main coronary artery disease or SXscore greater than or equal to 27 should require preoperative carotid screening in patients undergoing CABG, regardless of the presence of risk factors.