Gamma glutamyl transferase activity is independently associated with oxidative stress rather than SYNTAX score.

BACKGROUND: Gamma glutamyl transferase (GGT) is involved in the pathophysiologic process of coronary atherosclerosis. GGT activity plays a role in the catabolism of glutathione which is known as one of the major antioxidants. However, there is a lack of research on direct examination of relevance between serum GGT activity with systemic oxidative stress. OBJECTIVES: We aimed to investigate the relationship between GGT activity with systemic oxidative stress markers and the extent and complexity of coronary artery disease (CAD) assessed with SYNTAX score in stable CAD. METHODS: Measurements were obtained from 359 patients with stable CAD (Mean age = 57.7 ± 10.1 years). The patients were divided into two groups according to the median GGT level (GGT < median group < 22 and GGT > median group ≥ 22). Angiography was performed and SYNTAX score was calculated in all patients. Oxidative stress markers (total oxidant status [TOS], total antioxidant capacity [TAC] and oxidative stress index [OSI]) were measured in all patients. RESULTS: While SYNTAX score and oxidative stress markers such as TOS and OSI have been increased, TAC was decreased in GGT > median group compared with GGT < median group (p < 0.05, for all). GGT activity was independently associated with diabetes (ß = 0.106, p = 0.015) and OSI (ß = 0.556, p < 0.001) in multiple linear regression analysis. However, the independent association between GGT activity and SYNTAX score was not found in present study (ß = 0.063, p = 0.238). CONCLUSION: In stable CAD, increased GGT activity within the normal range is associated with increased oxidative stress rather than increased extent and complexity of CAD.

Serum 25-Hydroxyvitamin D Level and Aortic Intima-Media Thickness in Patients Without Clinical Manifestation of Atherosclerotic Cardiovascular Disease.

OBJECTIVES: Existing evidence suggests that impaired vitamin D metabolism contribute to the development of atherosclerosis. Aortic intima-media thickness (IMT) is an earlier marker than carotid IMT of preclinical atherosclerosis. However, there is a lack of researches on direct investigation of relevance between serum 25-hydroxyvitamin D (25(OH)D) and thoracic aortic IMT. In this study, we aimed to assess the relationship between thoracic aortic IMT and 25(OH)D. METHODS: We studied 117 patients (mean age: 45.5 ± 8.4 years) who underwent transesophageal echocardiography (TEE) for various indications. Serum 25(OH)D was measured using a direct competitive chemiluminescent immunoassay. The patients were divided into three groups according to the their serum 25(OH)D levels (VitDdeficiency , VitDinsufficient and VitDnormal groups). TEE was performed in all subjects. High sensitive C-reactive protein (hsCRP) and other biochemical markers were measured using an automated chemistry analyzer. RESULTS: Only 24.8% (29 patients) of patients had normal levels of 25(OH)D. The highest aortic IMT values were observed in VitDdeficiency group compared with VitDinsufficient and VitDnormal groups (P < 0.05, for all). Also aortic IMT values of VitDinsufficient group were higher than VitDnormal group (P < 0.05). 25(OH)D was independently associated with hs-CRP (ß = -0.442, P < 0.001) and aortic IMT (ß = -0.499, P < 0.001). CONCLUSIONS: The lower 25(OH)D level was independently associated with higher aortic IMT values. Therefore, hypovitaminosis D may have a role on pathogenesis of subclinical thoracic atherosclerosis.

Gamma Glutamyl Transferase Activity is Associated With Both Paraoxonase Activity and Aortic Stiffness in Hypertensive Patients.

BACKGROUND: We aimed to investigate relationship between gamma glutamyl transferase (GGT) activity with paraoxonase 1 (PON1) activity and aortic stiffness (AS) parameters such as pulse wave velocity (PWV) and augmentation index (AIx). METHODS: Measurements were obtained from 324 patients with newly diagnosed essential hypertension (mean age: 55.0 ± 8.2 years). The patients were divided into two groups according to their median GGT values. PWV and AIx were calculated using the single-point method via the Mobil-O-Graph® ARCsolver algorithm. RESULTS: PWV, Aix, and high-sensitive C-reactive protein (hs-CRP) values were higher and PON1 activity values were lower in GGThigh group compared with GGTlow group (P < 0.05, for all). Multiple linear regression analysis showed that GGT activity was independently associated with PWV (ß = 0.496, P < 0.001) and PON1 activity (ß = -0.343, P < 0.001) as well as hs-CRP (ß = 0.334, P < 0.001). CONCLUSION: These results may support that increased GGT activity would be associated with both impaired antioxidant system and increased AS in hypertensive patients.

Association between high-sensitivity troponin T, left ventricular hypertrophy, and myocardial performance index.

BACKGROUND: The prognostic importance of high-sensitivity cardiac troponin T (hs-cTnT) has recently been reported in patients with heart failure. The myocardial performance index (MPI), which combines parameters of both systolic and diastolic ventricular function, provides a better marker of left ventricular dysfunction in hypertensive patients with preserved left ventricular ejection fraction (LVEF). AIM: We aimed to investigate the relationship between hs-cTnT and tissue Doppler-derived MPI in newly diagnosed hypertensive patients with preserved LVEF. METHODS: We studied 306 patients with newly diagnosed hypertension. The patients were divided into two groups according to their median MPI values: MPIlo and MPIhigh groups. The MPI was calculated from the pulsed-wave Doppler recordings. Left ventricular mass index (LVMI) was determined according to the Devereux formula. hs-cTnT, uric acid, and high-sensitivity C-reactive protein (hs-CRP) levels were measured in all patients. RESULTS: Hs-cTnT, hs-CRP, and uric acid levels were higher in the MPIhigh group compared with the MPIlow group (p < 0.05, for all). The LVMI values in the MPIhigh group were higher than in the MPIlow group (p < 0.05). MPI was independently associated with age, uric acid, hs-cTnT, and LVMI in multivariate analysis. Multivariate logistic regression analysis showed that MPI and LVMI were independent predictors of high hs-cTnT level in newly diagnosed hypertensive patients with preserved LVEF. CONCLUSION: Hs-cTnT was independently associated with LV dysfunction and LV hypertrophy assessed with MPI in newly diagnosed hypertensive patients.

Relationship between mean platelet volume and morning blood pressure surge in newly diagnosed hypertensive patients.

OBJECTIVE: Morning blood pressure surge (MBPS) is an independent predictor of atherothrombotic cardiovascular events in hypertensive patients. There is evidence from studies supporting the validity of mean platelet volume (MPV) as a marker of vascular risk and predictor of thrombotic complications. The aim of this study is to investigate the relationship between MPV and MBPS in hypertensive patients. METHODS: Measurements were obtained from 298 patients with newly diagnosed essential hypertension (Mean age: 51.9 ± 11.7 years). The patients were divided into two groups (MPV(low) group; <10.8 fL, MPV(high) group; ≥ 10.8 fL). The MBPS was calculated as mean systolic BP during the 2 hours after awaking minus the mean systolic BP during the 1 hour that included the lowest sleep BP. RESULTS: MPV was independently associated with MBPS (ß=0.554, p<0.001) and hs-CRP level (ß=0.286, p<0.001). CONCLUSION: Finally, higher MPV values related to enhanced MBPS which are associated with atherothrombotic cardiovascular events.

Relationship of platelet indices with acute stent thrombosis in patients with acute coronary syndrome.

INTRODUCTION: Despite major advances in stent technology and antithrombotic therapy, the development of stent thrombosis continues to be a major problem in patients who have undergone percutaneous coronary intervention (PCI). Although a few studies have investigated the relationship between early stent thrombosis and platelet activity, the relationship between acute stent thrombosis (AST) (within the first 24 h) and platelet indices is unclear. AIM: We investigated the relationship between AST development and platelet indices in acute coronary syndrome patients. MATERIAL AND METHODS: In our case-control study, 33 patients who underwent PCI with subsequent AST development and 59 patients without AST were selected by propensity analysis. We compared the clinical, angiographic, and laboratory data between the AST and control groups. RESULTS: Mean platelet volume (MPV) (p=0.002) and platelet distribution width (p=0.014) were significantly higher and platelet count (p=0.017) was significantly lower in the AST group. Logistic regression analyses showed that MPV was a significant independent predictor of AST (OR = 1.67; 95% CI: 1.11-2.51; p=0.013). In the ROC analyses, the cut-off value of MPV to detect AST was > 9.1 fl with a sensitivity of 90.9%, a specificity of 42.4%, a positive predictive value of 46.9% and a negative predictive value of 89.3% (AUC: 0.687, 95% CI: 0.582-0.780, p=0.001). CONCLUSIONS: Our study shows that baseline MPV predicts the development of AST in patients with ACS. Mean platelet volume therefore might be an easily accessible marker in the identification of patients at high risk for the development of AST.

Oxidative stress and paraoxonase 1 activity predict contrast-induced nephropathy in patients with ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention.

Reactive oxygen species have been implicated in the pathogenesis of contrast-induced nephropathy (CIN). We investigated the relationship between CIN with paraoxonase 1 (PON-1) activity and oxidative stress markers (total antioxidant status [TAS], total oxidant status [TOS], and oxidative stress index [OSI]) in patients with anterior ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention; 289 consecutive patients with STEMI were prospectively included. The patients were divided into 2 groups: CIN (n = 69) and non-CIN (n = 220). Activity of PON-1 and TAS levels were significantly lower and OSI and TOS levels were significantly higher in patients with CIN compared to the non-CIN group (P < .05, for all). On multivariate logistic regression analysis, PON-1 activity and OSI as well as the amount of contrast medium and diabetes were independent predictors for CIN in patients with anterior STEMI. Activity of PON-1 and oxidative stress may play a role in the pathogenesis of CIN.

Evaluation of the effects of recipient/donor gender on early/late postoperative renal graft functions by renal scintigraphy.

OBJECTIVES: We discuss the effects of recipient/donor gender on renal allograft functions using scintigraphic parameters obtained 3 days after renal transplant and 1 year after transplant. MATERIALS AND METHODS: This retrospective study included 76 renal allograft recipients (group one, 38 males; group two, 38 females). Patients underwent scintigraphic imaging with Tc-99m DTPA on postoperative day 3 and 1 year after transplant. We used the Hilson perfusion index, maximum renal activity/background activity, ratio of renal activity at 20 minutes to renal activity at 3 minutes, time-to-peak activity, and glomerular filtration rate to measure quantitative parameters. RESULTS: On postoperative day 3, the Hilson perfusion index, maximum renal activity/background activity, the ratio of renal activity at 20 minutes to renal activity at 3 minutes, time-to-peak activity, and glomerular filtration rate values for male/female recipients were similar (P = .65, P = .77, P = .38, P = .10, P = .99). The gender of donors was compared with the above-mentioned scintigraphic parameters of the recipients, and no statistically significant differences were found (P = .24, P = .25, P = .44, P = .29, P = .13). At 1-year follow-up, values obtained from group 1 and group 2 recipients were similar. After 1 year, chronic rejection developed in 15.7% of group 1 recipients and in 10.5% of group 2 recipients; acute rejection developed in 21% of group 1 recipients and in 23.6% of group 2 recipients. There were no statistically significant differences between the occurrence of acute rejection and the gender of recipients or donors (P = 1.00, P = .45). CONCLUSIONS: We observed no statistically significant differences between renal graft functions and gender of the recipients/donors during the early/late posttransplant period.

Paraoxonase-1 activity and oxidative stress in patients with anterior ST elevation myocardial infarction undergoing primary percutaneous coronary intervention with and without no-reflow.

BACKGROUND: Reperfusion and ischemic injuries are pathogenetic mechanisms of no-reflow. Oxidative stress plays a critical role during ischemia as well as during the reperfusion phase following ST elevation myocardial infarction (STEMI). We sought to investigate the relationship between no-reflow with paraoxonase-1 (PON-1) activity and oxidative stress markers (total antioxidant capacity (TAC), total oxidant status (TOS), oxidative stress index (OSI), lipid hydro-peroxide (LOOH)) in patients with anterior STEMI undergoing primary percutaneous coronary intervention (PCI). METHODS: In this study, 319 consecutive anterior STEMI patients undergoing primary PCI were prospectively included (mean age 56.5 ± 12.5 years). The patients were divided into two groups as normal flow (n = 231) and no-reflow (n = 88) groups. Serum PON-1 activity was measured spectrophotometrically. TAC and TOS levels were determined by using an automated measurement method. LOOH levels were measured by ferrous oxidation with xylenol orange assay. RESULTS: PON-1 activity and TAC levels were significantly lower and TOS, OSI and LOOH levels were significantly higher in patients with no-reflow compared to normal flow group (p < 0.05, for all). On multivariate logistic regression analysis, PON-1 activity (ß = 0.976, 95% CI = 0.962-0.990, p = 0.001) and OSI (ß = 1.094, 95% CI = 1.042-1.148, p < 0.001) as well as diabetes, infarction time, thrombus score and initial SYNTAX score were independently associated with no-reflow. CONCLUSION: In patients with no-reflow compared with normal flow, oxidants are increased, while serum PON-1 activity and antioxidants are decreased. This result shows that increased oxidative stress has a role in the pathogenesis of no-reflow.

Paraoxonase (PON1) activity in patients with subclinical thoracic aortic atherosclerosis.

High density lipoprotein (HDL), a powerful antioxidant, protects low density lipoprotein (LDL) particles against oxidative stress. By limiting LDL oxidation, HDL plays an important role in preventing atherosclerosis (AS). The antioxidant effect of HDL is mostly associated with the paraoxonase (PON1) activity. It has been known that increased aortic intima-media thickness (IMT) is an earlier marker AS than carotid IMT. We aimed to investigate the association between thoracic aortic IMT and serum PON1 activity. We studied 133 patients (mean age: 46.3 ± 8 years) who underwent transesophageal echocardiography (TEE) for various indications. The measurements of thoracic aortic IMT by TEE are classified into four grades (1, 2, 3 and 4). Serum PON1 activity was measured spectrophotometrically. Oxidative and anti-oxidative status was evaluated by measuring serum lipid hydroperoxide (LOOH), total anti-oxidant status (TAS). Serum PON1 activity was progressively decreasing from grade 1 IMT to grade 4 IMT (p < 0.001). However, serum LOOH was significantly lower and TAS was significantly higher in patients with grade 1 when compared with other grades. In multiple linear regression analysis, IMT was independently correlated with PON1 activity (ß = -0.495, p < 0.001), TAS level (ß = -196, p < 0.009), age (ß = 0.145, p = 0.029) and LDL cholesterol level (ß = 0.169, p = 0.009). Decreased PON1 activity was independently associated with the extent of thoracic AS. PON1 activity may play a role in pathogenesis of thoracic AS besides age, TAS and LDL cholesterol levels.

Epicardial fat thickness in stable coronary artery disease: its relationship with high-sensitive cardiac troponin T and N-terminal pro-brain natriuretic peptide.

OBJECTIVES: Epicardial adipose tissue is related to coronary atherosclerosis, left ventricle hypertrophy, myocardial dysfunction, cardiomyopathy, and inflammation, which produces a variety of cytokines that influence key pathogenic mechanisms of atherogenesis. The main goal of this study is to examine the relationship between epicardial fat thickness (EFT) and cardiovascular risk markers as well as the complexity of coronary artery disease (CAD) in patients with stable CAD. MATERIALS AND METHODS: We prospectively included 439 stable CAD patients undergoing coronary angiography in the present study (mean age: 62.2±10.7 years). Patients were divided into two groups (EFTlow and EFThigh groups) according to their median EFT values. EFT was evaluated by two-dimensional echocardiography before angiography. The SYNTAX score was calculated in all patients. N-terminal pro-brain natriuretic peptide (NT-proBNP), high-sensitive C-reactive protein (hs-CRP), high-sensitive cardiac troponin T (hs-cTnT), uric acid, and other biochemical markers were also measured. RESULTS: Age, SYNTAX score, frequencies of diabetes, hyperlipidemia, and hypertension, NT-proBNP, hs-CRP, hs-cTnT, and uric acid levels were higher in EFThigh group compared with the EFTlow group (P<0.05 for all). EFT was associated independently with age (ß=-0.102, P=0.001), diabetes (ß=-0.083, P=0.011), SYNTAX score (ß=0.352, P<0.001), hs-CRP level (ß=0.217, P<0.001), hs-cTnT level (ß=0.197, P<0.001), and NT-proBNP level (ß=0.300, P<0.001) in multivariate analysis. CONCLUSION: EFT obtained by echocardiograpy may not only be an easy tool but also an important tool for early detection of increased cardiac risk as well as the extent and complexity of CAD in patients with stable CAD.

Increased aortic stiffness predicts contrast-induced nephropathy in patients with stable coronary artery disease undergoing percutaneous coronary intervention.

Increased aortic stiffness (AS) has been shown to be an independent risk factor for cardiovascular disease in renal failure and was also found to be associated with even mild renal insufficiency. We investigated the relationship between contrast-induced nephropathy (CIN) and AS parameters such as pulse wave velocity (PWV) and augmentation index (AIx). Patients (n = 440) with stable coronary artery disease (CAD) treated with percutaneous coronary intervention (PCI) were included prospectively (mean age: 60.3 ± 10.3 years). The PWV and AIx were calculated using the single-point method. The PWV, age, diabetes, SYNTAX score, and contrast media dose were independent predictors for CIN (P < .05, for all). The cutoff value for PWV obtained by the receiver-operator characteristic curve analysis was 10.35 m/s for the prediction of CIN (95% confidence interval: 0.838-0.916, sensitivity: 82.1%, specificity: 77.9%, and P < .001). In conclusion, a greater AS pre-PCI may predict CIN development in patients with stable CAD.