[The relationship between insulin resistance and left ventricular systolic and diastolic functions and functional capacity in patients with chronic heart failure and metabolic syndrome]. / Kronik kalp yetersizligi olan metabolik sendromlu hastalarda insülin direncinin sol ventrikül sistolik ve diyastolik fonksiyonu ve fonksiyonel kapasite ile iliskisi.

OBJECTIVES: The relationship between chronic heart failure (CHF) and insulin resistance (IR) has long been recognized. We examined the relationship of IR with left ventricular (LV) systolic and diastolic functions and functional capacity of CHF patients with metabolic syndrome. STUDY DESIGN: The study included 50 nondiabetic CHF patients with metabolic syndrome (NYHA class I-III; 40 men, 10 women; mean age 60+/-10 years). Metabolic syndrome was diagnosed according to the AHA/NHLBI (American Heart Association/National Heart, Lung, Blood Institute) criteria. Insulin resistance was determined by the homeostasis model assessment (HOMA). Pulse-wave Doppler echocardiography and tissue Doppler imaging were performed to assess LV structure and functions. RESULTS: Patients with LV ejection fraction 40% (n=25). Fasting plasma insulin concentrations and HOMA-IR did not differ significantly in this respect. No significant differences were found in LV geometrical patterns, diastolic and systolic functions in patients with (HOMA >or=2.7; n=19) or without (HOMA <2.7; n=31) HOMA-IR. However, patients with HOMA-IR had a lower NYHA functional capacity (p<0.0001). HOMA-IR showed significant increases in parallel with NYHA functional class. CONCLUSION: Our findings suggest that IR in CHF patients with metabolic syndrome is not associated with LV systolic and diastolic functions, but is strongly linked with worsening in NYHA functional capacity.

Relationship between elevated serum gamma-glutamyltransferase activity and slow coronary flow.

OBJECTIVES: We evaluated the relationship between coronary blood flow and serum gamma-glutamyltransferase (GGT) activity in patients with slow coronary flow (SCF). STUDY DESIGN: The study included 90 patients (47 men, 43 women; mean age 50.8+/-9.4 years) with SCF and 88 patients (45 men, 43 women; mean age 51.4+/-8.8 years) with coronary artery disease (CAD), whose diagnoses were made by coronary angiography. Patients with CAD had normal coronary flow. Coronary flow was quantified using the corrected TIMI frame count (TFC) method and serum levels of gamma-glutamyltransferase were measured. The results were compared with those of a control group consisting of 86 age- and sex-matched patients who had normal coronary arteries and normal coronary flow. RESULTS: The three groups were similar with respect to body mass index, presence of hypertension and diabetes mellitus, lipid profiles, and fasting glucose. The use of medications was significantly more common in the CAD group (p<0.01). Compared to the control group, serum GGT activity was significantly increased in both SCF and CAD groups (p<0.01), but these two groups did not differ significantly in this respect (p=0.71). The TFCs for all the epicardial coronary arteries and the mean TFC were significantly higher in the SCF group (p<0.01). Patients with CAD and the controls had similar TFC parameters. The mean TFC showed a positive and moderate correlation with serum GGT activity (r=0.326; p<0.001). In regression analysis, serum GGT activity was found as the only independent predictor of the mean TFC (beta=0.309; p<0.001). CONCLUSION: We have shown for the first time an association between increased serum GGT activity and SCF. Further clinical studies are needed to clarify the physiopathologic role of serum GGT activity in SCF.

Serum gamma-glutamyl transferase activity increased in patients with coronary artery ectasia.

BACKGROUND: Serum gamma-glutamyl transferase (GGT) activity, an enzyme responsible for the extracellular catabolism of antioxidant glutathione, may directly take part in atherogenesis and evolve as a potential biochemical risk indicator of cardiovascular morbidity and mortality. An important characteristic of coronary artery ectasia (CAE) is the fact that in 85% of the cases, atherosclerotic coronary disease accompanies it. The relation between CAE and serum GGT activity has not been studied so far. Hence, we decided to investigate the serum GGT level in patients with CAE. METHODS: We measured serum GGT activity in 88 consecutive patients (48 males) with isolated CAE and 86 patients with coronary artery disease (CAD) and 84 controls. CAE was defined as being without any stenotic lesions with a visual assessment of the coronary arteries showing a luminal dilatation 1.5-fold or more of the adjacent normal coronary segments. Four subgroups were created in accordance with the CAE extension in coronary arteries. RESULTS: There were no statistically significant differences in serum GGT activity among CAE and CAD groups. Serum GGT activity was found significantly increased in patients in both CAE and CAD groups, compared with those in control group (P<0.001, P<0.001, respectively). According to the CAE severity, there were no statistically significant differences in CAE among these subgroups. CONCLUSION: We have shown for the first time that patients with CAE have higher serum GGT activity compared with controls with normal coronary angiograms. Hence, serum GGT activity can be used as a follow-up marker in patients with CAE.