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Dive into the research topics where Abdurrahman Oguzhan is active.

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Featured researches published by Abdurrahman Oguzhan.


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.


International Journal of Cardiology | 2013

Prognostic value of neutrophil/lymphocyte ratio in patients with ST-elevated myocardial infarction undergoing primary coronary intervention: A prospective, multicenter study

Mehmet Gungor Kaya; Mahmut Akpek; Yat Yin Lam; Mikail Yarlioglues; Turgay Celik; Ozgur Gunebakmaz; Mustafa Duran; Seref Ulucan; Ahmet Keser; Abdurrahman Oguzhan; Michael Gibson

OBJECTIVE The pre-procedural neutrophil to lymphocyte ratio (N/L) is associated with adverse outcomes among patients with coronary artery disease but its prognostic value in ST-segment elevation myocardial infarction (STEMI) has not been fully investigated. This study evaluated the relations between pre-procedural N/L ratio and the in-hospital and long-term outcomes in STEMI patients undergoing primary percutaneous coronary intervention (PCI). METHODS A total of 682 STEMI patients presented within the first 6h of symptom onset were enrolled and stratified according to tertiles of N/L ratio based on the blood samples obtained in the emergency room upon admission. RESULTS The mean follow-up period was 43.3 months (1-131 months). In-hospital in-stent thrombosis, non-fatal myocardial infarction, and cardiovascular mortality increased as the N/L tertile ratio increased (p<0.001, p<0.001, p=0.003, respectively). Long-term in-stent thrombosis, non-fatal myocardial infarction and cardiovascular mortality also increased as the N/L ratio increased (p<0.001, p<0.001, p=0.002, respectively). On multivariate analysis, N/L ratio remained an independent predictor for both in-hospital (OR 1.189, 95% CI 1.000-1.339; p<0.001) and long-term major (OR 1.228, 95% CI 1.136-1.328; p<0.001) adverse cardiac events. CONCLUSION The N/L ratio was an independent predictor of both in-hospital and long-term adverse outcomes among STEMI patients undergoing primary PCI. Our findings suggest that this inexpensive, universally available hematological marker may be incorporated into the current established risk assessment model for STEMI.


Circulation | 1999

Effect of Potential Confounding Factors on the Thrombolysis in Myocardial Infarction (TIMI) Trial Frame Count and Its Reproducibility

Adnan Abaci; Abdurrahman Oguzhan; Namık Kemal Eryol; Ali Ergin

BACKGROUND The potential factors that introduce variability into TIMI frame count (TFC) have not been systematically investigated. The goal of this study was to determine if nitrate use, dye injection rate, catheter size, the phase of the cardiac cycle in which dye is injected, or heart rate affect the TFC and to investigate the reproducibility of the TFC. METHODS AND RESULTS The dye injection rate was increased 1 mL/s, and angiography was repeated. A coronary angiogram was taken first with an 8F catheter and then with a 6F catheter. After taking angiograms, intracoronary nitrate was given to the patient, and the second angiography was performed. Basal heart rate was increased 20 beats/min, and angiography was repeated. Dye injection was performed at the beginning of systole and diastole. The TFC was not significantly changed by increasing the dye injection rate (P=0.467) or by changing catheter size (P=0.693). Nitrate administration significantly increased the TFC from 26.4+/-11.9 to 32.8+/-13.3 frames (P<0.001). Dye injection at the beginning of diastole significantly decreased the TFC from 30.1+/-8.8 to 24.4+/-7.9 frames (P<0.001) for the left coronary artery and from 24.16+/-4.49 to 21. 24+/-4.45 frames (P<0.001) for the right coronary artery. Increasing heart rate significantly decreased the TFC from 30.4+/-6.1 to 25. 3+/-7.2 frames (P<0.001). Intraobserver and interobserver reproducibility of the TFC was good (mean difference, 1.33+/-1.24 and 2.57+/-1.72 frames, respectively). CONCLUSIONS Nitrate use, heart rate, and the phase of the cardiac cycle in which dye is injected had significant effects on the TFC. Therefore, studies comparing TFC need to consider these factors, and the use of nitrates should be either standardized or randomized.


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.


Echocardiography-a Journal of Cardiovascular Ultrasound and Allied Techniques | 2005

Preload Dependence of Doppler Tissue Imaging Derived Indexes of Left Ventricular Diastolic Function

Abdurrahman Oguzhan; Huseyin Arinc; Adnan Abaci; Ramazan Topsakal; Namık Kemal Eryol; Ibrahim Ozdogru; Emrullah Basar; Ali Ergin

Doppler tissue imaging (DTI) has been proposed as a tool for the evaluation of diastolic function. Controversy exists regarding whether DTI measurements are influenced by preload. Changes in the circulating volume associated with hemodialysis result in preload reduction. To determine the influence of preload reduction on DTI and standard pulsed‐Doppler transmitral diastolic velocities, 30 patients (mean age 41 ± 14) with chronic renal insufficiency without overt heart disease were studied by DTI and standard pulsed Doppler before and after hemodialysis. From the apical window, DTI sample volume was placed at the lateral and septal mitral annulus and at the midsegment of lateral and septal myocardial wall of the left ventricle. Peak early diastolic annular and myocardial, and peak late diastolic annular and myocardial velocities were measured. Transmitral peak early and late diastolic velocities were also recorded by standard pulsed Doppler. The peak velocity of early diastolic mitral flow decreased from 100 ± 30 to 85 ± 34 cm/s (P < 0.001) after hemodialysis. Hemodialysis elicited marked reduction in early diastolic lateral mitral annular and midlateral myocardial velocities (6.9 ± 3.2 to 6.3 ± 2.9 cm/s, P < 0.04 and 6.7 ± 0.3 to 5.5 ± 2 cm/s, P < 0.001, respectively). Early diastolic, septal mitral annular, and midseptal myocardial velocities were also significantly decreased (5.8 ± 2.8 to 4.6 ± 2 cm/s, P < 0.006 and 6.2 ± 2 to 5.1 ± 1 cm/s, P < 0.008, respectively). Late diastolic mitral annular and myocardial velocities did not change. It is concluded that early diastolic mitral annular and myocardial velocities are affected by acute preload reduction. It is necessary to consider preload when diastolic function is assessed by DTI.


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.


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.


Angiology | 2015

Predictive Value of Admission Platelet Volume Indices for In-hospital Major Adverse Cardiovascular Events in Acute ST-Segment Elevation Myocardial Infarction

Turgay Celik; Mehmet Gungor Kaya; Mahmut Akpek; Ozgur Gunebakmaz; Sevket Balta; Bahadir Sarli; Mustafa Duran; Sait Demirkol; Onur Kadir Uysal; Abdurrahman Oguzhan; C. Michael Gibson

Although mean platelet volume (MPV) is an independent correlate of impaired angiographic reperfusion and 6-month mortality in ST-segment elevation myocardial infarction (STEMI) treated with primary percutaneous coronary intervention (pPCI), there is less data regarding the association between platelet distribution width (PDW) and in-hospital major adverse cardiovascular events (MACEs). A total of 306 patients with STEMI pPCI were evaluated. No reflow was defined as a post-PCI thrombolysis in myocardial infarction (TIMI) flow grade of 0, 1, or 2 (group 1). Angiographic success was defined as TIMI flow grade 3 (group 2). The values of MPV and PDW were higher among patients with no reflow. In-stent thrombosis, nonfatal myocardial infarction, in-hospital mortality, and MACEs were significantly more frequent among patients with no reflow. In multivariate analysis, PDW, MPV, high-sensitivity C-reactive protein, and glucose on admission were independent correlates of in-hospital MACEs. Admission PDW and MPV are independent correlates of no reflow and in-hospital MACEs among patients with STEMI undergoing pPCI.

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