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Dive into the research topics where Metin Karayakalı is active.

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Featured researches published by Metin Karayakalı.


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.


Medical Science Monitor | 2012

Cardiotrophin-1 plasma levels are increased in patients with diastolic heart failure

Atac Celik; Semsettin Sahin; Fatih Koc; Metin Karayakalı; Mehmet Ali Sahin; İsmail Benli; Hasan Kadi; Turgay Burucu; Köksal Ceyhan; Unal Erkorkmaz

Summary Background Cardiotrophin-1 (CT-1) is a member of the interleukin (IL-6) family of cytokines and is increased in various cardiovascular diseases, including chronic heart failure. The aim of the study was to determine if plasma CT-1 is associated with diastolic heart failure (DHF) and to investigate the relationship between CT-1 and echocardiographic parameters. Material/Methods Fifty-seven consecutive patients (mean age 57±8 years, 24 males) diagnosed with DHF in our clinic and 33 controls (mean age 55±7 years, 12 males) were included in the study. All study participants underwent echocardiographic evaluation and blood samples were obtained. Results CT-1 and NT-proBNP values were significantly higher in DHF subjects than in controls (11.30 [8.09–16.51] vs. 17.5 [8.95–28.74] fmol/mL, P=0.017 and 64 [27.5–95] vs. 82 [55.5–241] pg/mL, P=0.009, respectively). The mitral peak velocity of early diastolic filling (E), mean ratio of E to early diastolic mitral annular velocity (E/Em), and the pulmonary capillary wedge pressure (PCWP) estimated from E/Em measurements were all significantly higher in the patient group (62.27±14.69 vs. 75.67±18.85 cm/sec, 6.40±1.48 vs. 10.30±3.48, and 10 [9–11]vs. 14[12–16] mmHg, P≤0.001 for all). Lateral and septal Em were significantly lower in the patient group (10.69±1.87 vs. 8.69±2.00 cm/sec and 8.91±1.22 vs. 6.65±1.58 cm/sec, P<0.001 for both). CT-1 positively correlated with NT-proBNP (P=0.001, r=0.349), mean E/Em (P=0.003, r=0.307), and estimated mean PCWP (P=0.001, r=0.308). Conclusions CT-1 is elevated in patients with DHF and is associated with NT-proBNP and estimated left ventricular filling pressures.


Clinical and Applied Thrombosis-Hemostasis | 2012

Assessment of red cell distribution width (RDW) in patients with coronary artery ectasia.

Orhan Dogdu; Fatih Koc; Nihat Kalay; Mikail Yarlioglues; Deniz Elcik; Metin Karayakalı; Kerem Özbek; Mehmet Gungor Kaya

Objectives: Coronary artery ectasia (CAE) is characterized by an abnormal dilatation of the coronary arteries. Red cell distribution width (RDW) is a measure of heterogeneity in the size of red blood cell. In this study, we aimed to investigate RDW levels in patients with CAE. Methods: The study population included 54 patients with CAE (28 males; mean age, 59 ± 12) and 40 individuals comprising the control group who had normal coronary arteries (17 males; mean age, 56 ± 10). Admission RDW was measured as part of the automated complete blood count. Results: The RDW was significantly higher in the CAE group than the control (P < .001). Also, high-sensitive C-reactive protein (hs-CRP) levels in patients with CAE were significantly higher as compared with controls (P < .001). Conclusion: This study demonstrates that RDW and hs-CRP were higher in the CAE group compared with the control group. These results show that RDW is a reliable, simple, and inexpensive marker for patients with CAE.


Annals of Noninvasive Electrocardiology | 2015

New Markers for Ventricular Repolarization in Coronary Slow Flow: Tp-e Interval, Tp-e/QT Ratio, and Tp-e/QTc Ratio

Kayihan Karaman; Fatih Altunkaş; Mustafa Çetin; Metin Karayakalı; Arif Arısoy; Ilker Akar; Cemil Zencir; Barış Aygüç; Ataç Çelik

Coronary slow flow (CSF) is characterized by normal or near‐normal coronary arteries with delayed opacification of the distal vasculature that it may cause angina pectoris, acute myocardial infarction, life‐threatening arrhythmias, and sudden cardiac death. The Tp‐e interval, Tp‐e/QT ratio, and Tp‐e/QTc ratio are also known as predictors of ventricular arrhythmogenesis. The aim of this study was to assess ventricular repolarization in patients with CSF by using Tp‐e interval, Tp‐e/QT ratio, and Tp‐e/QTc ratio.


Medical Principles and Practice | 2012

Coronary Ectasia Is Associated with Impaired Left Ventricular Myocardial Performance in Patients without Significant Coronary Artery Stenosis

Köksal Ceyhan; Fatih Koc; Kurtulus Ozdemir; Atac Celik; Fatih Altunkaş; Metin Karayakalı; Hasan Kadi; Ahmet Ozturk; Mehmet Gungor Kaya

Objectives: To determine both ventricular functions and tissue Doppler echocardiography (TDE)-derived myocardial performance index (MPI) in patients with coronary artery ectasia (CAE). Subjects and Methods: Twenty-five patients with CAE (13 men; mean age 57 ± 9 years) and 25 age- and sex-matched controls without CAE (8 men; mean age 54 ± 10 years) were enrolled in the study. Left and right ventricular functions were detected using conventional echocardiography and TDE. Results: Left ventricle-lateral wall (0.61 ± 0.17; 0.50 ± 0.10, p = 0.02), interventricular septum (0.66 ± 0.17; 0.52 ± 0.10, p = 0.007) and mean MPI (0.63 ± 0.15; 0.51 ± 0.09, p = 0.004) were increased in the CAE group compared to the control group. Right ventricular MPI was similar in both the CAE and control groups (0.58 ± 0.18; 0.52 ± 0.19, p > 0.05). Conclusion: The findings show that left ventricular MPI is different in CAE patients without obstructive coronary artery disease compared to the normal control group. Also in these patients, right ventricular MPI was similar to the control group.


Kaohsiung Journal of Medical Sciences | 2012

Relationship between red cell distribution width and echocardiographic parameters in patients with diastolic heart failure

Atac Celik; Fatih Koc; Hasan Kadi; Köksal Ceyhan; Unal Erkorkmaz; Turgay Burucu; Metin Karayakalı; Orhan Onalan

Red cell distribution width (RDW) was found to be a prognostic marker in heart failure patients. The aim of the study was to investigate the relationship between RDW and echocardiographic parameters in diastolic heart failure (DHF). Seventy‐one consecutive DHF patients (26 men) and 50 controls (21 men) were included in the study. All of the study population underwent echocardiographic evaluation, and blood samples were obtained. RDW and N‐terminal pro‐B‐type natriuretic peptide (NT‐proBNP) values were significantly higher, whereas there was an increasing trend for high‐sensitivity C‐reactive protein levels in DHF patients than those in controls (p < 0.001, p < 0.001, and p = 0.064, respectively). All of the echocardiographic parameters evaluating diastolic function were more deteriorated in the DHF group. Patients who had an RDW value greater than the cutoff point also had higher NT‐proBNP levels, an elevated ratio of mitral peak velocity of early diastolic filling to early diastolic mitral annular velocity, and increased estimated pulmonary capillary wedge pressures by tissue Doppler parameters, but lower creatinine clearance (p < 0.05 for all). According to the cutoff values calculated using receiver operating characteristic analysis, RDW > 13.6% and NT‐proBNP > 125 pg/mL have high diagnostic accuracy for predicting DHF. RDW values were increased in the DHF population. Our results suggest that the high RDW levels in patients with DHF may be related to increased neurohormonal activity, impaired renal functions, and elevated filling pressure, but not to increased inflammation.


Journal of Investigative Medicine | 2013

Sodium Bicarbonate Versus Isotonic Saline for the Prevention of Contrast-Induced Nephropathy in Patients With Diabetes Mellitus Undergoing Coronary Angiography and/or Intervention: A Multicenter Prospective Randomized Study

Fatih Koc; Kurtulus Ozdemir; Fatih Altunkaş; Atac Celik; Orhan Dogdu; Metin Karayakalı; Enes Elvin Gul; Unal Erkorkmaz; Hasan Kadi; Mahmut Akpek; Mehmet Gungor Kaya

Introduction Contrast-induced nephropathy (CIN) is a leading cause of acute renal failure and affects mortality and morbidity. Although the incidence of CIN is quite low in the general population, CIN incidence is significantly increased in patients with diabetes mellitus (DM). Objectives We compared the efficacy of prophylactic use consisting of a saline infusion or a sodium bicarbonate infusion for the prevention of CIN in patients with DM. Materials and Methods A total of 195 DM patients who had unselected renal function were randomized into 2 groups: 101 patients were assigned to saline infusion, and 94 patients were assigned to bicarbonate infusion. The primary end point was the maximum increase in the serum creatinine (SCr) level, whereas the secondary end point was the development of CIN after the procedure. Results The maximum increase in SCr levels was significantly lower in the saline group than in the bicarbonate group: −0.03 mg/dL (IQR, −0.09 to 0.10 mg/dL) versus 0.02 mg/dL (IQR, −0.09 to 0.13 mg/dL) (P = 0.014). The rate of CIN was significantly lower in the saline group than in the bicarbonate group (5.9% vs 16%, P = 0.024). In the subset of study participants with a baseline creatinine clearance of less than 60 mL/min, the maximum increase in SCr levels was significantly lower, −0.08 mg/dL (IQR, −0.13 to −0.04 mg/dL), in the saline group than in the bicarbonate group, 0.03 mg/dL (IQR, −0.13 to 0.12 mg/dL) (P = 0.004). Conclusions The use of prophylactic hydration with isotonic saline before coronary procedures may decrease SCr levels and reduce the incidence of CIN in patients with DM with unselected renal functions to a greater extent than sodium bicarbonate can.


Coronary Artery Disease | 2011

Antioxidant status and levels of antioxidant vitamins in coronary artery ectasia.

Fatih Koc; Nihat Kalay; Idris Ardic; Kerem Özbek; Atac Celik; Köksal Ceyhan; Hasan Kadi; Metin Karayakalı; Semsettin Sahin; Fatih Altunkaş; Orhan Onalan; Mehmet Gungor Kaya

BackgroundCoronary artery ectasia (CAE) is a rare coronary artery anomaly. In this study, we investigated superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and &ggr;-glutamyltransferase (GGT) activities, and antioxidant vitamin levels (vitamins A and E) in patients with CAE. MethodsForty-five patients who were diagnosed with CAE using coronary angiography were included in the study (26 men; mean age, 57±9 years). The control group consisted of 35 participants who had normal coronary arteries as shown by coronary angiography (14 men; mean age, 54±7 years). The plasma activity of SOD, GSH-Px, GGT, and levels of vitamins A and E were measured. ResultsThe plasma SOD activity was significantly lower in the CAE group compared with the control group (0.70±0.64 vs. 1.52±0.85 U/ml; P=0.001). The serum GGT activity was higher in the CAE group compared with the control group (34±20 vs. 26±13 U/ml; P=0.04). There were no significant differences in the plasma GSH-Px activity and vitamin A and E levels. There was a positive correlation between SOD activity and low-density lipoprotein cholesterol levels (r=0.418; P=0.01). There was also a positive correlation between vitamin E and low-density lipoprotein cholesterol (r=0.410; P=0.01) and triglyceride levels (r=0.310; P=0.04) in patients with CAE. ConclusionIn this study, patients with CAE had a decreased SOD plasma activity and an increased GGT activity compared with normal controls. These results suggest that oxidative stress and antioxidant status may have an important role in the pathogenesis of CAE.


Medical Principles and Practice | 2014

The Effect of Slow Coronary Flow on Right and Left Ventricular Performance

Fatih Altunkaş; Fatih Koc; Köksal Ceyhan; Atac Celik; Hasan Kadi; Metin Karayakalı; Kerem Özbek; Turgay Burucu; Ahmet Öztürk; Orhan Onalan

Objective: To evaluate left and right ventricular functions using tissue Doppler echocardiography (TDE) and myocardial performance index (MPI) methods in patients with slow coronary flow (SCF) and to determine the relationship between these parameters and thrombolysis in myocardial infarction frame count in SCF patients. Subjects and Methods: Thirty-five patients (20 males and 15 females) with SCF who underwent coronary angiography and 35 age- and sex-matched controls (14 males and 21 females) without SCF who underwent elective coronary angiography were enrolled in the study. Left ventricular (LV) and right ventricular (RV) functions were examined using conventional echocardiography and TDE. Results: LV systolic myocardial velocity (Sm), early myocardial velocity (Em), late myocardial velocity (Am), and Em/Am ratio were similar in both the SCF and control groups; however, isovolumetric relaxation time (IRT) was higher in the SCF group compared to the control group (IRT: 99 ± 17 vs. 88 ± 20; p = 0.01). In patients with SCF, LV MPI was higher than in the control group, but this was not statistically significant (0.61 ± 0.11 vs. 0.56 ± 0.12; p = 0.07). The RV tricuspid annular velocities and MPI were similar in the SCF and control groups. Conclusion: This study showed that SCF affected LV functions echocardiographically and could cause partially reduced LV performance. In addition, SCF did not affect RV functions echocardiographically.


Anatolian Journal of Cardiology | 2015

The protective effect of single dose tadalafil in contrast-induced nephropathy: an experimental study.

Kerem Özbek; Köksal Ceyhan; Fatih Koc; Erkan Sogut; Fatih Altunkaş; Metin Karayakalı; Atac Celik; Hasan Kadi; R. Doğan Köseoğlu; Orhan Onalan

Objective: Contrast-induced nephropathy (CIN) is one of the most common causes of acute renal failure in hospitalized patients. The direct toxic effect of contrast media; ischemic damage caused by reactive oxygen species; increased perivascular hydrostatic pressure; high viscosity and changes in the activity of vasoactive substances play important roles in the pathogenesis. Tadalafil inhibits the phosphodiesterase enzyme which destroys nitric oxide. Nitric oxide causes renal vasodilatation, increases renal medullar blood flow and mediates the removal of free oxygen radicals. Drugs that increase levels of nitric oxide are expected to reduce the development of contrast nephropathy due to contrast media. We aimed to test the hypothesis that tadalafil reduces the development of contrast nephropathy due to contrast toxicity. Methods: A total of 24 female Wistar albino rats, three groups of eight, were included in the study. After 48 hours of dehydration, contrast media (meglumine diatrozoate, 6 mL/kg) was administered to the first group, and contrast media with tadalafil (10 mg/kg) was administered to the second group. The third group served as the control group. Blood and tissue samples were taken 48 hours after this procedure. Results: Serum cystatin C, serum creatinine and blood urea nitrogen (BUN) values were significantly lower in the contrast with tadalafil group compared to the group given only contrast. Serum and tissue malondialdehyde (MDA) levels were significantly lower in the contrast with tadalafil group than in the contrast only group. Conclusion: These results demonstrate the protective effect of tadalafil in the prevention of CIN in rats.

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Atac Celik

Gaziosmanpaşa University

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Fatih Altunkaş

Gaziosmanpaşa University

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Köksal Ceyhan

Gaziosmanpaşa University

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Fatih Koc

Gaziosmanpaşa University

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Hasan Kadi

Gaziosmanpaşa University

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Kerem Özbek

Gaziosmanpaşa University

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Arif Arısoy

Gaziosmanpaşa University

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Orhan Onalan

Gaziosmanpaşa University

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İlker Akar

Gaziosmanpaşa University

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