Onur Kaypaklı

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.

Mean platelet volume is independently associated with renal dysfunction in stable coronary artery disease.

Abstract It has been suggested that athero-thrombotic risk progressively increases as the glomerular filtration rate (GFR) declines. Mean platelet volume (MPV) is the most commonly used measure of platelet size, and higher MPV value is independent risk factor for athero-thrombotic disease such as myocardial infarction. We aimed to evaluate the association between estimated GFR and MPV in patients with stable coronary artery disease showing normal to mildly impaired renal function. A total of 471 patients (288 males and 183 females; mean age: 62.5 + 9.5 years) with angiographically proven CAD were included. The patients were divided into two groups according to the estimated GFR value (GFRlow group: GFR <60 ml/minute per 1.73 m2 and GFRhigh group: GFR ≥ 60, ml/min per 1.73 m2). Estimated GFR was calculated according to the Cockcroft–Gault formula. MPV, high-sensitive C-reactive protein (hsCRP) and other biochemical markers were measured in all patients. Prevalent of CAD was determined by the SYNTAX score. Patients with GFRlow group were of older age, had higher incidence of female gender, current smoker, diabetes, hypertension and hyperlipidemia, lower values of total cholesterol, LDL cholesterol, hemoglobin and platelet count and higher values of BMI, SYNTAX score, hs-CRP and MPV compared with patients with GFRhigh group. Multivariate linear regression analysis showed that the MPV was independently related with diabetes (β = 0.189, p < 0.001), eGFR (β = −0.267, p < 0.001), hs-CRP level (β = 0.158, p < 0.001) and platelet count (β = −0.116, p = 0.002). In conclusion, MPV is independently associated with GFR as well as hsCRP, platelet count and diabetes. These findings may explain, in part, the increase in athero-thrombotic risk with slightly impaired renal function.

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 (β = 0.976, 95% CI = 0.962-0.990, p = 0.001) and OSI (β = 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.

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.

Relationship between platelet indices and international normalized ratio in patients with non-valvular atrial fibrillation

Abstract Atrial fibrillation (AF) is the most common sustained arrhythmia and associated with adverse outcomes and increased risk for thromboembolic events. Warfarin is still the most extensively prescribed oral anticoagulant in AF to prevent ischemic complications. We aimed to determine the differences at platelet indices with warfarin usage layered by International Normalized Ratio (INR). A total of 250 patients with permanent non-valvular AF (mean age 70.2 ± 9.1; 153 female) were divided into two groups. Group 1 included 125 patients whose INR is between 2.0 and 3.0 (called as “effective”) and Group 2 included 125 patients whose INR is <2.0 (called as “ineffective”). Also 123 age- and sex-matched individuals in sinus rhythm enrolled as control group (Group 3). After physical and echocardiographic examination, complete blood counts and INR were studied. There was no statistically significant difference in age, sex, co-morbidities and medications, also hemoglobin, white blood cell and platelet counts among the groups. The CHA2DS2-VASc scores were similar between Groups 1 and 2. The mean platelet volume (MPV), platelet distribution width (PDW) and plateletcrit (PCT) were significantly higher in Group 2 than Groups 1 and 3 and similar between Groups 1 and 3. MPV was positively correlated with PDW and PCT and also inversely correlated with INR value and platelet count. On multivariate logistic regression analysis, MPV, PDW and PCT were independent predictors of ineffectiveness of INR. The results of this study showed that MPV, PDW and PCT are increased in patients with non-valvular AF without effective warfarin treatment. Warfarin usage adjusted by INR is associated with lower values of these platelet indices, even lower as the values of subjects in sinus rhythm. MPV, PDW and PCT are independent predictors of INR ineffectiveness and seem to be useful parameters for monitoring the effectiveness of warfarin treatment.

High-Sensitivity Cardiac Troponin T Predicts Nondipper Hypertension in Newly Diagnosed Hypertensive Patients

The increased prognostic accuracy of the high‐sensitivity cardiac troponin T (hs‐cTnT) assay vs the conventional cTnT assay has recently been reported in hypertensive patients. The authors aimed to investigate the significance of serum hs‐cTnT marker for prediction of nondipper hypertension (HTN) in hypertensive patients. A total of 317 patients with newly diagnosed HTN were studied. The patients were divided into two groups: 198 dipper hypertensive patients (mean age, 51.7±5.1 years) and 119 nondipper hypertensive patients (mean age, 53.4±7.6 years). Hs‐cTnT and N‐terminal pro‐brain natriuretic peptide (NT‐proBNP) were measured in all patients. hs‐cTnT and NT‐proBNP were independent predictors for nondipper HTN (P<.05 for all). The cutoff value of hs‐cTnT obtained by the receiver operator curve analysis was 7.55 ng/L for the prediction of nondipper HTN (sensitivity: 79%, specificity: 70%; 95% confidence interval, 0.769–0.860; P<.001). In patients with HTN, higher serum concentration of hs‐cTnT even within normal range is an independent predictor of nondipper HTN.

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

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.

High-sensitivity cardiac troponin T levels in newly diagnosed hypertensive patients with different left ventricle geometry.

Abstract Background. The high-sensitivity cardiac troponin T (hs-cTnT) assay provides important prognostic information on cardiovascular diseases. Although hs-cTnT is associated with left ventricle (LV) hypertrophy (LVH), it has not been investigated in different LV geometric patterns incorporating normal LV structure and concentric remodeling in addition to LVH. Objectives. We aimed to investigate the possible association between hs-cTnT and LV geometric patterns in newly diagnosed hypertensive patients. Methods. We studied 306 patients with newly diagnosed hypertension (HT; mean age 51.7 ± 5.6 years) and 44 healthy control subjects (mean age 51.3 ± 4.7 years). Echocardiographic examination was performed in all subjects. Four different geometric patterns were determined in hypertensive patients according to LV mass index (LVMI) and relative wall thickness (RWth). hs-cTnT and other biochemical markers were measured in all participants. Results. The highest hs-cTnT values were observed in the concentric hypertrophy group compared with the control, normal geometry, concentric remodeling and eccentric hypertrophy groups (p < 0.05, for all). Also, hs-cTnT values of the eccentric hypertrophy group were higher than the control, normal geometry and concentric remodeling groups (p < 0.05, for all). Multivariate regression analysis showed that hs-cTnT was independently associated with LV geometry (β = 0.326, p = 0.001) as well as LVMI (β = 0.228, p = 0.010) and creatinine level β = 0.132, p = 0.012). Conclusion. hs-cTnT level is related not only to LVH but also to LV geometry in hypertensive patients. hs-cTnT levels may mediate poorer LV geometric patterns in 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 (MPVlow group; <10.8 fL, MPVhigh 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 (β=0.554, p<0.001) and hs-CRP level (β=0.286, p<0.001). Conclusion: Finally, higher MPV values related to enhanced MBPS which are associated with atherothrombotic cardiovascular events.

High-Sensitivity Cardiac Troponin T is Associated with SYNTAX Score and Diabetes Mellitus in Patients with Stable Coronary Artery Disease

High-sensitivity cardiac troponin T (hs-cTnT) and the Synergy between Percutaneous Coronary Intervention with Taxus and Cardiac Surgery (SYNTAX) score are emerging as important prognostic markers in stable coronary artery disease (CAD). We aimed to investigate the relationship between hs-cTnT and extent and complexity of CAD assessed with STNTAX score. Measurements were obtained from 411 patients with stable CAD (Mean age=61.7 ± 9.9 years, male/female=247/164). The patients were divided into two groups according to the median hs-TnT value (hs-cTnTlow group<9.65 pg/ml and hs-cTnThigh group ≥ 9.65 pg/ml). SYNTAX score values were higher in hs-cTnThigh group compared with hs-cTnTlow group (p<0.05). Hs-cTnT was independently associated with SYNTAX score (β=0.661, p<0.001) and diabetes (β=0.107, p=0.031) in multiple linear regression analysis. The cutoff value of hscTnT obtained by the ROC curve analysis was 9.62 ng/L for the prediction of higher SYNTAX score. In multivariate logistic regression analysis, hs-cTnT, age, diabetes, creatinine and hs-CRP were an independent predictor for higher SYNTAX score. Despite very low circulating concentrations, changes in hs-cTnT concentrations are associated with extent and complexity of CAD and presence of diabetes in patients with stable CAD.