OBJECTIVES: Sufficient coronary collateral circulation (CCC) protects myocardial tissue against ischemia in patients with coronary chronic total occlusion (CTO). In this study, we aimed to investigate whether there is an association between serum γ-glutamyl transferase (GGT) levels and development of CCC in patients with coronary CTO. MATERIALS AND METHODS: A total of 203 patients with CTO at coronary angiography were included in this study. On the day of admission to the hospital, blood samples were taken and GGT levels were analyzed for all patients. Development of collateral circulation was graded according to the Rentrop classification after coronary angiography. Then, patients were divided into two groups on the basis of CCC grades: group 1 included 99 patients (49%) with poorly developed CCC, and group 2 included 104 patients (51%) with well-developed CCC. RESULTS: Patients with poorly developed CCC had significantly higher serum GGT levels compared with those with well-developed CCC, (66.5±16 vs. 51.8±10 U/l, P<0.0001). Correlation analysis showed an inverse correlation between GGT levels and the Rentrope score (r=-0.579, P<0.001). Logistic regression analysis showed that GGT level was an independent predictor of poorly developed CCC (odds ratio 0.92, 95% confidence interval 0.90-0.94; P<0.001). CONCLUSION: Increased serum GGT levels independently predict poorly developed CCC in patients with coronary CTO. Our results show that GGT is a simple and readily available marker for sufficiency of CCC in patients with CTO.
OBJECTIVES: Sufficient coronary collateral circulation (CCC) protects myocardial tissue against ischemia in patients with coronary chronic total occlusion (CTO). In this study, we aimed to investigate whether there is an association between serum γ-glutamyl transferase (GGT) levels and development of CCC in patients with coronary CTO. MATERIALS AND METHODS: A total of 203 patients with CTO at coronary angiography were included in this study. On the day of admission to the hospital, blood samples were taken and GGT levels were analyzed for all patients. Development of collateral circulation was graded according to the Rentrop classification after coronary angiography. Then, patients were divided into two groups on the basis of CCC grades: group 1 included 99 patients (49%) with poorly developed CCC, and group 2 included 104 patients (51%) with well-developed CCC. RESULTS:Patients with poorly developed CCC had significantly higher serum GGT levels compared with those with well-developed CCC, (66.5±16 vs. 51.8±10 U/l, P<0.0001). Correlation analysis showed an inverse correlation between GGT levels and the Rentrope score (r=-0.579, P<0.001). Logistic regression analysis showed that GGT level was an independent predictor of poorly developed CCC (odds ratio 0.92, 95% confidence interval 0.90-0.94; P<0.001). CONCLUSION: Increased serum GGT levels independently predict poorly developed CCC in patients with coronary CTO. Our results show that GGT is a simple and readily available marker for sufficiency of CCC in patients with CTO.