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Dive into the research topics where Nihat Kalay is active.

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Featured researches published by Nihat Kalay.


International Journal of Cardiology | 2013

Protective effects of nebivolol against anthracycline-induced cardiomyopathy: A randomized control study

Mehmet Gungor Kaya; Metin Ozkan; Ozgur Gunebakmaz; Hasan Akkaya; Esma Kaya; Mahmut Akpek; Nihat Kalay; Mustafa Dikilitas; Mikail Yarlioglues; Halit Karaca; Veli Berk; Idris Ardic; Ali Ergin; Yat Yin Lam

BACKGROUND We aimed to evaluate the effect of prophylactic nebivolol use on prevention of antracycline-induced cardiotoxicity in breast cancer patients. METHODS In this small, prospective, double-blind study, we randomly assigned 45 consecutive patients with breast cancer and planned chemotheraphy to receive nebivolol 5mg daily (n=27) or placebo (n=18). Echocardiographic measurements and N-terminal pro-brain natriuretic peptide (NT-pro-BNP) levels were obtained at baseline and at 6-month of chemotherapy. RESULTS Both studied groups had comparable echocardiographic variables and NT-pro-BNP levels at baseline. At 6-month, the left ventricular (LV) end-systolic and end-diastolic diameters increased in the placebo group (LVESD: 29.7 ± 3.4 to 33.4 ± 4.5mm; LVEDD: 47.2 ± 3.8 to 52.0 ± 4.6mm, p=0.01 for both) but remained unchanged in the nebivolol group (LVESD: 30.4 ± 3.5 to 31.0 ± 3.6mm, p=0.20; LVEDD: 47.0 ± 4.4 to 47.1 ± 4.0mm, p=0.93). The placebo group also had lower LVEF than the nebivolol group (57.5 ± 5.6% vs. 63.8 ± 3.9%, p=0.01) at 6-month. NT-pro-BNP level remained static in the nebivolol group (147 ± 57 to 152 ± 69 pmol/l, p=0.77) while it increased in the placebo group (144 ± 66 to 204 ± 73 pmol/l, p=0.01). CONCLUSIONS Prophylactic use of nebivolol treatment may protect the myocardium against antracycline-induced cardiotoxicity in breast cancer patients.


Atherosclerosis | 2010

Platelet activation and inflammatory response in patients with non-dipper hypertension

Mehmet Gungor Kaya; Mikail Yarlioglues; Ozgur Gunebakmaz; Ertugrul Gunturk; Tugrul Inanc; Ali Dogan; Nihat Kalay; Ramazan Topsakal

OBJECTIVE Non-dipper hypertensives had about three times the risk of atherosclerotic events than hypertensives whose blood pressure was >10% lower at night compared to daytime (dippers). Platelet activation and inflammatory response may derive from most atherosclerotic events. Mean platelet volume (MPV) is a determinant of platelet activation and high sensitive C-reactive protein (hs-CRP) is the best candidate assay to identify and monitor the inflammatory response. We aimed to determine whether MPV and hs-CRP levels are elevated in non-dipper patients compared to dippers and healthy controls. In addition, we tried to find out if MPV and CRP are related to each other or not in non-dipper hypertensives. METHOD The total 126 patients study group included 86 patients with hypertension and 40 healthy subjects (16 male, mean age; 51+/-4) as control. Ambulatory blood pressure monitoring was performed for all patients. Hypertensive patients were divided into two groups; 46 dipper patients (18 male, mean age; 50+/-9) and 40 non-dipper patients (17 male, mean age; 53+/-11). Clinical baseline characteristics were similar between groups. We measured mean platelet volume in a blood sample collected in EDTA tubes and high-sensitive CRP was measured by using BN2 model nephlometer. RESULTS Non-dipper patients demonstrated higher levels of MPV compared to dippers and normotensives (9.72+/-0.52 fl vs 9.38+/-0.33 fl and 8.92+/-0.42 fl, p<0.05, respectively). High-sensitive CRP levels were also significantly higher in non-dippers compared to dippers and normotensives (4.9+/-1.7mg/l vs 3.8+/-1.5mg/l and 2.7+/-0.8mg/l, p<0.05, respectively). There was significant positive correlation between MPV and CRP levels (p=0.002, r=0.482) in non-dipper hypertensives. CONCLUSION Our results suggest that patients with non-dipping tend to have increased platelet activation and inflammatory response. Increased platelet activation and inflammatory response could contribute to increase the atherosclerotic risk in non-dipper patients compared to dippers.


Angiology | 2012

Hematologic Parameters and Angiographic Progression of Coronary Atherosclerosis

Nihat Kalay; Orhan Dogdu; Fatih Koc; Mikail Yarlioglues; Idris Ardic; Mahmut Akpek; Davran Çiçek; Abdurrahman Oguzhan; Ali Ergin; Mehmet Gungor Kaya

Hematologic parameters have prognostic importance in cardiovascular disease. However, the relation between atherosclerosis progression and hematologic parameters is not well defined. A total of 394 patients requiring repeat coronary angiography were included in the study. According to angiography, patients were divided into 2 groups, progressive (n = 196) and nonprogressive (n = 198) diseases. Hematologic parameters including mean platelet volume (MPV) and neutrophil/lymphocyte (N/L) ratio were measured. Glucose, creatinine, and cholesterol were significantly higher in the progressive group. Mean platelet volume count was similar in both groups. The N/L ratio was significantly higher in the progressive group (5.0 ± 5.1 vs 3.2 ± 3; P = .001). In multivariate analysis, the N/L ratio was significantly related with progression (relative risk [RR]: 2.267, 95% CI: 1.068-4.815, P = .03). Progression rate was significantly high in patients with high N/L ratio (39% vs 56%). Our results suggest that the N/L ratio is a predictor of progression of atherosclerosis.


Atherosclerosis | 2011

The association of serum uric acid levels on coronary flow in patients with STEMI undergoing primary PCI

Mahmut Akpek; Mehmet Gungor Kaya; Huseyin Uyarel; Mikail Yarlioglues; Nihat Kalay; Ozgur Gunebakmaz; Orhan Dogdu; Idris Ardic; Deniz Elcik; Omer Sahin; Abdurrahman Oguzhan; Ali Ergin; Charles Michael Gibson

OBJECTIVE Uric acid has been shown as a predictor and an independent risk factor for coronary heart disease, but little is known regarding the association of uric acid levels with coronary blood flow in STEMI. We hypothesized that elevated uric acid levels would be associated with impaired flow and perfusion in the setting of STEMI treated with primary PCI. METHODS Two hundred and eighty nine patients with STEMI who treated primary PCI were enrolled to study. Patients were divided into two groups based upon the TIMI flow grade. No-reflow was defined as TIMI Grade 0, 1 and 2 flows (group 1). Angiographic success was defined as TIMI 3 flow (group 2). Uric acid, MPV and high sensitive CRP were measured. Major adverse cardiac events (MACE) were defined as in stent thrombosis, non-fatal myocardial infarction and in-hospital mortality. RESULTS There were 126 patients (mean age 63±11 and 71% male) in group 1 and 163 patients (mean age 58±12 and 80% male) in group 2. Uric acid, MPV, and hs-CRP levels on admission were higher in group 1 (p=0.0001 for each). A uric acid level ≥5.4 mg/dl measured on admission had a 77% sensitivity and 70% specificity in predicting no-reflow at ROC curve analysis. In-hospital MACE was significantly higher in group 1 (29% vs. 7%, p=0.0001). At multivariate analyses, high plasma uric acid (odds ratio (OR) 2.05, <95% confidence interval(CI) 1.49-2.81; p<0.0001), hs-CRP (OR 1.02, <95% CI 1.01-1.03; p=0.0007) and MPV (OR 3.09, <95% CI 1.95-4.89; p<0.0001) levels were independent predictors of no-reflow post primary PCI and uric acid (OR 2.75, <95% CI 1.93-3.94; p<0.0001), hs-CRP (OR 1.01, <95% CI 1-1.02; p=0.006) levels, but not MPV, were independent predictors of in-hospital MACE. CONCLUSION Plasma uric acid level on admission is a strong and independent predictor of poor coronary blood flow following primary PCI and in hospital MACE among patients with STEMI. Except for predictive value, uric acid levels may be a useful biomarker for stratification of risk in patients with STEMI and may also lead to carry further therapeutic implications.


American Journal of Cardiology | 2012

Prognostic Value of Uric Acid in Patients With ST-Elevated Myocardial Infarction Undergoing Primary Coronary Intervention

Mehmet Gungor Kaya; Huseyin Uyarel; Mahmut Akpek; Nihat Kalay; Mehmet Ergelen; Erkan Ayhan; Turgay Isik; Gökhan Çiçek; Deniz Elcik; Omer Sahin; Said M. Cosgun; Abdurrahman Oguzhan; Mehmet Eren; C. Michael Gibson

Elevated uric acid (UA) levels have been associated with cardiovascular disease in epidemiologic studies. The relation between UA levels and long-term outcomes in patients with ST-segment elevation myocardial infarction who undergo primary percutaneous coronary intervention is not known. Data from 2,249 consecutive patients with ST-segment elevation myocardial infarction who underwent primary percutaneous coronary intervention were evaluated. Patients were divided into 2 groups with high or low UA using upper limits of normal of 6 mg/dl for women and 7 mg/dl for men. There were 1,643 patients in the low-UA group (mean age 55.9 ± 11.6 years, 85% men) and 606 patients in the high-UA group (mean age 60.5 ± 12.6 years, 76% men). Serum UA levels were 8.0 ± 1.5 mg/dl in the high-UA group and 5.2 ± 1.0 mg/dl in the low-UA group (p <0.001). The in-hospital mortality rate was significantly higher in patients with high UA levels (9% vs 2%, p <0.001), as was the rate of adverse outcomes in patients with high UA. The mean follow-up time was 24.3 months. Cardiovascular mortality, reinfarction, target vessel revascularization, heart failure, and major adverse cardiac events were all significantly higher in the high-UA group. In a multivariate analyses, high plasma UA levels were an independent predictor of major adverse cardiac events in the hospital (odds ratio 2.03, 95% confidence interval 1.25 to 3.75, p = 0.006) and during long-term follow-up (odds ratio 1.64, 95% confidence interval 1.05 to 2.56, p = 0.03). In conclusion, high UA levels on admission are independently associated with in-hospital and long-term adverse outcomes in patients with ST-segment elevation myocardial infarction who undergo primary percutaneous coronary intervention.


European Journal of Heart Failure | 2015

Protective effects of spironolactone against anthracycline-induced cardiomyopathy

Mahmut Akpek; Ibrahim Ozdogru; Omer Sahin; Mevlude Inanc; Ali Dogan; Cevat Yazici; Veli Berk; Halit Karaca; Nihat Kalay; Abdurrahman Oguzhan; Ali Ergin

The protective effect of beta‐blockers, ACE inhibitors, and ARBs on anthracycline cardiotoxicity has already been demonstrated, but the effect of aldosterone antagonism, which inhibits the last step of the renin–angiotensin–aldosterone system (RAAS), was questioned. This study sought to investigate whether spironolactone protects the heart against anthracycline‐induced cardiotoxicity.


Blood Pressure | 2011

Effect of long-term and high-dose allopurinol therapy on endothelial function in normotensive diabetic patients

Ali Dogan; Mikail Yarlioglues; Mehmet Gungor Kaya; Zakir Karadağ; Serap Dogan; Idris Ardic; Orhan Dogdu; Yusuf Kilinc; Cemil Zencir; Mahmut Akpek; Ibrahim Ozdogru; Abdurrahman Oguzhan; Nihat Kalay

Abstract Objectives. Endothelial dysfunction is a well known risk factor for atherosclerosis. Uric acid levels are associated with endothelial dysfunction and atherosclerosis even if in physiological range. Xanthine oxidase inhibition with allopurinol decreases uric acid levels and oxidative stress and improves endothelial function. We have investigated the effect of high-dose and long-term allopurinol therapy on endothelial function in diabetic normotensive patients. Methods. This study is a randomized, single-blind, placebo-controlled trial. Both treatment and placebo groups consisted of 50 patients. In the treatment group, daily oral 900 mg allopurinol was started after randomization and maintained for 12 weeks. Brachial artery flow-mediated dilatation (FMD) and nitrate-induced dilatation (NID) were measured at baseline and after the allopurinol therapy to evaluate endothelial function. Results. HbA1c and uric acid levels decreased after allopurinol therapy (6.1 ± 2.1 vs 5.5 ± 1.0%, 5.0 ± 0.8 vs 3.3 ± 0.5 mg/dl, respectively, p = 0.01) but no change was observed in the placebo group (7.7 ± 1.9% vs 7.6 ± 2.0%, 5.3±2.1 vs 5.6 ± 0.8 mg/dl, respectively, p > 0.05). FMD and NID increased significantly in the treatment group (5.6 ± 2.1% vs 8.5 ± 1.2%, 10 ± 7.4% vs 14 ± 4.0%, 10 ± 7.4% vs 14 ± 4.0%, respectively, p = 0.01), whereas no change was observed in the placebo group (5.8 ± 1.8% vs 6.1 ± 0.8%, 12 ± 9.5 vs 10 ± 3.8%, respectively, p > 0.05). Conclusion. Long-term and high-dose allopurinol therapy significantly improved endothelial function in diabetic normotensive patients. In addition, allopurinol therapy contributes to the lower HbA1c levels.


Türk Kardiyoloji Derneği arşivi : Türk Kardiyoloji Derneğinin yayın organıdır | 2011

The relationship between inflammation and slow coronary flow: increased red cell distribution width and serum uric acid levels

Nihat Kalay; Metin Aytekin; Mehmet Gungor Kaya; Kerem Özbek; Metin Karayakalı; Erkan Sogut; Fatih Altunkaş; Ahmet Ozturk; Fatih Koc

OBJECTIVES The underlying mechanism of slow coronary flow (SCF) has yet to be elucidated. Increased red cell distribution width (RDW) and uric acid level may be indicative of an underlying inflammatory state. We aimed to investigate RDW and serum uric acid levels in patients with normal coronary arteries and SCF without stenosis. STUDY DESIGN The study included 46 consecutive patients (25 males, 21 females; mean age 54 ± 11 years) with angiographically normal coronary arteries but having SCF in all three coronary arteries. The control group consisted of 40 patients (18 males, 22 females; mean age 54 ± 9 years) with angiographically normal coronary arteries without SCF. In both groups, RDW and serum uric acid levels were measured and compared. RESULTS In the SCF group, TIMI frame counts measured in the left anterior descending coronary artery, left circumflex coronary artery, and right coronary artery were significantly higher compared to the control group (p<0.05). Patients with SCF exhibited significantly higher RDW (13.4 ± 1.6% vs. 12.6 ± 1.2%, p=0.01) and serum uric acid levels (5.3 ± 1.6 mg/dl vs. 4.7 ± 1.3 mg/dl, p=0.01) compared to controls. In logistic regression analysis, uric acid [Exp(B)=1.612, 95% CI 0.206-5.35, p=0.021] and RDW [Exp(B)=1.496, 95% CI 0.403-4.72, p=0.030] were found as independent predictors of SCF. CONCLUSION Our findings show that patients with SCF have significantly increased RDW and serum uric acid levels. This may help throw more light on the pathophysiological basis of SCF.


Blood Pressure | 2011

Relationship between mean platelet volume levels and subclinical target organ damage in newly diagnosed hypertensive patients

Mikail Yarlioglues; Mehmet Gungor Kaya; Idris Ardic; Orhan Dogdu; Hacı Ahmet Kasapkara; Ertugrul Gunturk; Mahmut Akpek; Nihat Kalay; Ali Dogan; Ibrahim Ozdogru; Abdurrahman Oguzhan

Abstract Background. Significant numbers of asymptomatic hypertensive patients are attacked by subclinical target organ damage (TOD) such as proteinuria, left ventricular hypertrophy and carotid atherosclerosis. Platelets become activated in uncontrolled hypertension and play a crucial role in increased thrombotic tendency. Mean platelet volume (MPV) is one of the markers that correlate closely with platelet activity. We aimed to investigate the relationship between MPV levels and subclinical TOD in newly diagnosed hypertensive patients. Methods. 80 newly diagnosed hypertensive patients were enrolled to this cross-sectional study. Ambulatory blood pressure monitoring was performed for all patients. Left ventricular mass index (LVMI), carotid intima-media thickness (IMT) and urine albumin/creatinine ratio (UACR) were measured as indices of cardiac, vascular and renal damage, respectively. MPV was measured from blood samples collected in EDTA tubes and high-sensitivity C reactive protein (hs-CRP) was measured by using nephlometer. Results. MPV was significantly correlated with 24-h systolic–diastolic blood pressure (r = 0.52 and r = 0.55, respectively). Correlation analysis indicated that MPV was moderately related with UACR, LVMI, carotid IMT and hs-CRP (r = 0.50, r = 0.55, r = 0.60 and r = 0.69, respectively, p = 0.0001). Multivariable analysis identified that MPV levels were independently associated with severity of proteinuria, carotid IMT and LVMI (p = 0.001). Conclusion. Our findings suggested that MPV levels were associated with severity of subclinical TOD including; carotid atherosclerosis, left ventricular hypertrophy and renal damage, in hypertensive patients. In addition to this, MPV levels were significantly correlated with hs-CRP levels and 24-h ambulatory blood pressure measurements.


International Journal of Cardiology | 2012

Intravenous N-acetylcysteine plus high-dose hydration versus high-dose hydration and standard hydration for the prevention of contrast-induced nephropathy: CASIS—A multicenter prospective controlled trial

Fatih Koc; Kurtulus Ozdemir; Mehmet Gungor Kaya; Orhan Dogdu; Mehmet Akif Vatankulu; Selim Ayhan; Unal Erkorkmaz; Osman Sonmez; Meryem Ulku Aygul; Nihat Kalay; Mehmet Kayrak; Turgut Karabağ; Yusuf Izzettin Alihanoglu; Ozgur Gunebakmaz

BACKGROUND Contrast-induced nephropathy (CIN) is a leading cause of acute renal failure and affects mortality and morbidity. We investigated the efficacy of prophylactic intravenous (IV) N-acetylcysteine (NAC) and hydration for the prevention of CIN in patients with mild to moderate renal dysfunction who are undergoing coronary angiography and/or percutaneous coronary intervention (PCI). METHODS A total of 220 patients who had mild to moderate renal dysfunction with serum creatinine (SCr) ≥ 1.1mg/dL or creatinine clearance ≤ 60 mL/min were randomized in 3 groups: 80 patients were assigned to IV NAC plus high-dose hydration with normal saline, 80 patients to only high-dose hydration with normal saline and 60 patients to standard hydration with normal saline (control group). The primary end point was the alteration of SCr level. The secondary end point was the development of CIN after the procedure. RESULTS SCr levels changed the least in the NAC plus high-hydration group (P=0.004). The rate of the CIN in the NAC plus high-dose hydration group was also lower than the high-dose hydration group (P=0.006). No significant differences in the primary and secondary end points were found between high-dose hydration and control group. CONCLUSION The results of this study suggest that NAC plus high-dose hydration was superior to high-dose hydration alone as well as standard hydration for the protection of renal functions in patients with mild to moderate renal dysfunction who are undergoing coronary angiography and/or PCI. High-dose hydration without NAC was not better than standard hydration alone.

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