The relationship between Gamma-Glutamyltransferase activity and atrial fibrillation ın patients with reduced ejection fraction heart failure

Objective: Clinically, gamma-glutamyltransferase (GGT)  activity is generally used as a diagnostic test for liver function, biliary tract pathologies, and alcohol consumption. GGT is the enzyme that manages the extracellular catabolism of the main antioxidant glutathione, thus increasing the oxidative stress or inflammatory state. Recently studies reported that GGT is related to cardiovascular mortality and morbidity independently alcohol consumption. Elevation of GGT in heart failure (HF), atrial fibrillation (AF), coronary artery disease, myocardial infarction, and metabolic syndrome is explained with inflammation and oxidative stress.  Aim of this study, we have examined the relation between GGT and AF in reduced ejection fraction heart failure (HFrEF) patients group.

Method: Totally one hundred and sixty-three ischemic HF patients were included in the study retrospectively.  Electrocardiographically 63 patients have AF (40 male, 23 females, mean age: 73±8 years) and 100 patients have normal sinus rhythm (75 male, 25 female, mean age: 71±7 years). All patients had the echocardiographic examination, ejection fraction (EF)> 40%, severe valvular heart disease, and nonischemic HF patients were excluded.

Results: Presence of hypertension, age, gender, dislipidemia history, diabetes, smoking condition, fasting glucose, and cholesterol levels were compared between two groups and there were not statistically different (p>0.05 for all).  However, serum GGT activity was increased in patients group with AF compared to those without AF (35(10-121) U/L versus 27(6-113)U/L, p=0.01). The optimal cut-off GGT activity for AF patients were >23,5 IU/l with a sensitivity of 81% and a specificity of 46% (AUC =0.660, 95% CI=0.575 - 0.744)  

Conclusions: In this study, serum GGT activity was concluded to be increased in HFrEF patients with AF compared to without AF group. More comprehensive studies should be planned to improve the clinical use of GGT in patients with HFrEF and to investigate the relationship between GGT and AF.