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Featured researches published by Oner Ozdogan.


Nephrology Dialysis Transplantation | 2011

Relations between malnutrition–inflammation–atherosclerosis and volume status. The usefulness of bioimpedance analysis in peritoneal dialysis patients

Meltem Sezis Demirci; Cenk Demirci; Oner Ozdogan; Fatih Kircelli; Fehmi Akcicek; Ali Basci; Ercan Ok; Mehmet Ozkahya

BACKGROUND Chronic fluid overload (FO) is frequently present in peritoneal dialysis (PD) patients and is associated with hypertension and left ventricular hypertrophy and dysfunction, which are important predictors of death in dialysis patients. In the present study, we investigated the relationship between nutrition, inflammation, atherosclerosis and body fluid volumes measured by multi-frequency bioimpedance analysis (m-BIA) in PD patients. In addition, we analysed the relationship of extracellular volume values by m-BIA to echocardiographic parameters in order to define its usefulness as a measure of FO. METHODS Ninety-five prevalent PD patients (mean age 50 ± 13 years, 10 of them diabetic) were enrolled. Extracellular water (ECW), total body water (TBW), dry lean mass (DLM) and phase angle (PA) were measured by m-BIA. Volume status was determined by measuring left atrium diameter (LAD) and left ventricular end-diastolic diameter (LVEDD). Measurement of carotid artery intima-media thickness (CA-IMT) was used to assess the presence of subclinical atherosclerosis. Serum albumin was used as a nutritional marker, and serum C-reactive protein (CRP) was used as an inflammatory marker. RESULTS Mean ECW/height was 10.0 ± 1.0 L/m for whole group and 9.3 ± 0.6 L/m in patients with normal clinical hydration parameters. In correlation analysis, markers of nutrition, inflammation and atherosclerosis correlated well with m-BIA parameters. When we used echographically measured LAD (> 40 mm) or LVEDD (> 55 mm) as a confirmatory parameter, a cut-off value of 10.48 L/m ECW/height (78% specificity, with a sensitivity of 77% for LAD and 72% specificity, with a sensitivity of 70% for LVEDD) was found in ROC analysis for the diagnosis of FO. Patients with FO were older and had higher systolic blood pressure, cardiothoracic index, serum CRP level and mean CA-IMT than patients without FO. Patients with inflammation had higher CA-IMT values. In multivariate analysis, only two factors-low urine output and ECW/height-were independently associated with the presence of inflammation. CONCLUSIONS FO defined by m-BIA is significantly correlated with markers of malnutrition, inflammation and atherosclerosis in PD patients. The indices obtained from m-BIA, especially ECW/height, correlated well with volume overload as assessed by echocardiography and might be a measure worth testing in a properly designed clinical study.


American Heart Journal | 2010

Left atrial volume predicts mortality in low-risk dialysis population on long-term low-salt diet

Oner Ozdogan; Meral Kayikcioglu; Gulay Asci; Mehmet Ozkahya; Huseyin Toz; Meltem Sezis; Levent Can; Ercan Ok

BACKGROUND Echocardiography provides insight to the management of end-stage renal disease (ESRD) and might be valuable in assessing the prognosis. We evaluated the predictive value of echocardiography along with clinical findings in a low-risk hemodialysis (HD) population who had been treated with strict salt restriction strategy for blood pressure control. METHODS Study population consisted of a cohort of 555 ESRD patients from 8 HD centers where the same strict volume control strategy applied for blood pressure control. Clinical findings and echocardiography were examined as predictors of mortality for a mean follow-up period of 3 years (29.6 +/- 11.6 months). RESULTS During the follow-up, 89 patients (16%) died. Left atrium (LA) volume index was the only independent echocardiographic predictor of mortality (hazard ratio 1.025, 95% CI 1.001-1.050, P = .042). The other predictors of mortality were age, pulse pressure, diabetes mellitus, and high-sensitivity C-reactive protein. However, when we added interdialytic weight gain (IDWG) ratio to the Cox model, it also appeared as an independent predictor of mortality, whereas LA volume index no longer was. CONCLUSIONS Increased LA volume index emerged as the only independent echocardiographic determinant of mortality in low-risk dialysis patients treated by strict volume control. Close relationship with IDWG ratio indicates the intermittent stretching of atrium between dialysis sessions leading to atrial remodeling. This index is not the result of a single factor such as age, hypervolemia, or left ventricular hypertrophy but reflects the combination of these contributing causes. Therefore, it might be considered as an overall echocardiographic sign of mortality in ESRD.


Cardiovascular Therapeutics | 2008

Levosimendan versus Dobutamine in Heart Failure Patients Treated Chronically with Carvedilol

Hamza Duygu; Ugur Turk; Oner Ozdogan; Serdar Akyuz; Bahadir Kirilmaz; Emin Alioglu; Ramazan Gunduz; Yasemin Turan Bozkaya; Cuneyt Turkoglu; Serdar Payzin

INTRODUCTION Although beta-blockers are highly effective in the treatment of heart failure (HF), many patients with HF receiving a beta-blocker continue to become decompensated and require hospitalization for worsening HF. Levosimendan and dobutamine are used to manage decompensated HF, but their comparative effects on left ventricular (LV) function in patients prescribed beta-blockers are unknown. AIMS The aim of this study was to compare the effects of dobutamine and levosimendan on LV systolic and diastolic functions in chronic HF patients treated chronically with carvedilol. Forty patients with chronic HF who had NYHA class III to IV symptoms, a LV ejection fraction (LVEF) <40%, and ongoing treatment with carvedilol were enrolled in this randomized (1:1), dobutamine controlled, open-label study. Before and 24 h after treatment, LVEF, mitral inflow peak E and A wave velocity, E/A ratio, the deceleration time of the E wave (DT), isovolumic relaxation time (IVRT), peak systolic (Sm) and early diastolic (Em) mitral annular velocity, and systolic pulmonary artery pressure (SPAP) were measured by echocardiography. RESULTS Levosimendan produced a statistically significant increase in LVEF (28+/-5% vs. 33+/-3%), Sm (6.5+/-1.2 cm/s vs. 7.4+/-0.9 cm/s), DT (120+/-10 ms vs. 140+/-15 ms), and Em (7.5+/-0.4 cm/s vs. 8.1+/-0.5 cm/s) and significant decrease in E/A ratio (2.1+/-0.3 vs. 1.7+/-0.4) and SPAP (55+/-5 mmHg vs. 40+/-7 mmHg). No significant change occurred in LV systolic and diastolic function parameters, or SPAP with dobutamine treatment. Levosimendan did not significantly alter the heart rate (72+/-4 bpm vs. 70+/-3 bpm), systolic (105+/-5 mmHg vs. 102+/-4 mmHg), or diastolic blood pressure (85+/-5 mmHg vs. 83+/-5 mmHg) whereas with dobutamine treatment, all these parameters significantly increased. CONCLUSIONS Dobutamine and levosimendan have different effects on LV functions in patients treated chronically with carvedilol. These differences should be considered when selecting inotropic therapy for decompensated HF receiving long-term carvedilol.


Atherosclerosis | 2012

Effects of thrice weekly nocturnal hemodialysis on arterial stiffness

Meltem Sezis Demirci; Gulperi Celik; Mehmet Ozkahya; Murat Tumuklu; Huseyin Toz; Gulay Asci; Soner Duman; Ali Basci; Fatih Kircelli; Oner Ozdogan; Cenk Demirci; Levent Can; Ismet Onder Isik; Ercan Ok

OBJECTIVE In this study, we compared the changes in arterial stiffness in chronic hemodialysis patients treated with 8-h vs. 4-h thrice weekly in-center hemodialysis. METHODS Sixty prevalent chronic hemodialysis patients assigned to 8-h nocturnal in-center thrice weekly HD (NHD) and 60 control cases assigned to 4-h thrice weekly conventional HD (CHD) were followed for one year. Radial-carotid pulse wave velocity, augmentation index and echocardiography were performed at baseline and 12th month. RESULTS Mean age of the patients was 49±11 years, 30.8% were female, 27.5% had diabetes mellitus and mean dialysis vintage was 57±47 months. Baseline demographical, clinical and laboratory parameters were similar between groups. During a mean follow-up of 15.0±0.1 months, blood pressure remained similar in both groups while the number of mean daily anti-hypertensive substances decreased in the NHD group. In the NHD group, time-averaged serum phosphorus and calcium-phosphorus product were lower than the CHD group. Pulse wave velocity and augmentation index decreased in the NHD group (from 11.02±2.51 m/s to 9.61±2.39 m/s and from 28.8±10.3% to 26.2±12.1%; p=0.008 and p=0.04, respectively). While augmentation index increased in the CHD group (28.0±9.4 to 31.0±10.7%, p=0.02), pulse wave velocity did not change. Subendocardial viability ratio and ejection duration improved in the NHD group (from 135±28 to 143±25%, p=0.01 and from 294±34 ms to 281±34 ms, p=0.003, respectively), accompanied by regression of left ventricular mass index. In multiple stepwise linear regression analyses, NHD was associated with improvements in augmentation index, ejection duration and subendocardial viability ratio. CONCLUSIONS These data indicate that arterial stiffness is ameliorated by implementation of longer hemodialysis sessions.


Journal of The American Society of Echocardiography | 2010

Assessment of left atrial appendage function during sinus rhythm in patients with hypertrophic cardiomyopathy: transesophageal echocardiography and tissue doppler study.

Selcen Yakar Tülüce; Meral Kayikcioglu; Kamil Tuluce; Meral Gulsum Yilmaz; Oner Ozdogan; Mehmet Aydin; Can Hasdemir

BACKGROUND The incidence of systemic thromboembolism is high in patients with hypertrophic cardiomyopathy (HCM). The authors hypothesized that vulnerability to such vascular events could be caused by depressed left atrial appendage (LAA) function during normal sinus rhythm (SR). The aim of this cross-sectional study was to investigate LAA contractile function during SR in patients with HCM. METHODS LAA function was assessed in 62 patients with HCM in SR and compared with that in 53 age-matched and sex-matched controls. Patients with histories of atrial fibrillation and documented episodes of paroxysmal atrial fibrillation on 24-hour Holter monitoring and depressed left ventricular ejection fractions (<50%) were excluded. Multiplane transesophageal echocardiography was performed for determination of the morphology and function of the LAA. RESULTS LAA thrombi were present in five patients (8%) with HCM. LAA emptying and filling Doppler velocities were significantly depressed in the HCM group. LAA emptying and filling velocities were negatively correlated with age in controls (r = -0.4, P = .005), but these velocities were not associated with age in the HCM group. Moreover, LAA velocities were not associated with left ventricular mass index, left ventricular outflow tract gradient, or the degree of diastolic dysfunction in the HCM group. All Doppler tissue imaging velocities obtained from LAA walls were also significantly depressed in the HCM group. CONCLUSIONS LAA thrombus formation was not rare in this patient population. The significantly depressed LAA filling and emptying velocities in SR may predispose patients with HCM to thromboembolic events. The depressed Doppler tissue imaging LAA parameters in patients with HCM may indicate the presence of a possible intrinsic atrial myopathy. Thromboembolic risk should be taken into account, and the evaluation of LAA morphology and function by transesophageal echocardiography might become a component of routine workup in patients with HCM in the future.


Anatolian Journal of Cardiology | 2015

Echocardiographic signs of right ventricle changes after Trastuzumab treatment in breast cancer patients with erb-2 overexpression.

Barış Kılıçaslan; Oner Ozdogan; Gönül Demir Pişkin; Nihan Kahya Eren; Hüseyin Dursun

Objective: Left ventricular (LV) dysfunction after trastuzumab treatment in erb-2 breast cancer cases has been fully investigated. However, there is not enough data about the effect of trastuzumab treatment on right ventricular (RV) functions. This study is designed to evaluate the right heart changes by performing echocardiography after trastuzumab treatment in patients with erb-2 breast cancer. Methods: Forty-two consecutive breast cancer patients with erb-2 overexpression mean age 50.4±11.6 years who were decided to receive trastuzumab treatment were enrolled. Echocardiographic examinations including 2-D, spectral, and tissue Doppler measurements were performed at the baseline (T1) and repeated after 6 months (T2). Results: Tricuspid annular plane systolic excursion (TAPSE) was decreased, RV myocardial performance index (RVMPI) and tricuspid E/e’ ratio was increased after trastuzumab treatment (1.84 vs. 2.14; p<0.01) (0.46 vs. 0.56, p<0.01) (4.4±1.07 vs. 5.08±1.46; p=0.04). Median serum NT-ProBNP levels, troponin I, and hs-CRP levels were similar between the groups. LVEF and TAPSE were negatively correlated with dosage of trastuzumab (r=-0.392, p=0.04; r=-0.522, p=0.006). There was a stepwise decrease in LVEF when trastuzumab used with anthracyclines however this not reached statically significant (62.4±2, 60±4.5; p=0.06). Conclusion: In our study; we observed a trend of RV deterioration after trastuzumab treatment. These preliminary RV changes were demonstrated by using TAPSE, RV tissue Doppler imaging derived MPI and E/e’ ratio parameters by echocardiography and these parameters could also use as markers of trastuzumab toxicity in this population.


Türk Kardiyoloji Derneği arşivi : Türk Kardiyoloji Derneğinin yayın organıdır | 2015

The relationship between neutrophil to lymphocyte ratio and blood pressure variability in hypertensive and normotensive subjecs.

Barış Kılıçaslan; Hüseyin Dursun; Sermin Kaymak; Mehmet Aydin; Cenk Ekmekci; İbrahim Susam; Oner Ozdogan

OBJECTIVES Blood pressure (BP) variability is associated with hypertensive (HT) target organ damage and cardiovascular events. The aim of this study was to investigate the relation between neutrophil to lymphocyte ratio (NLR) and BP variability in hypertensive and normotensive subjects. STUDY DESIGN In this cross-sectional study, 150 subjects (63 male, mean age 52.1±5.2 years) were enrolled. In all patients, blood samples and 24-hour ambulatory blood pressure (BP) monitoring were obtained. According to 24-hour ambulatory BP results, participants were divided into four investigation categories. Group 1= Normotensive dipper (ND), Group 2= Normotensive non-dipper (NN), Group 3= HT dipper (HD), Group 4= HT non-dipper (HN). RESULTS Highest NLR values were determined in the HN group (p=0.005 vs. ND, p=0.046 vs. NN and p<0.01 vs. HD). NLR values were similar among the ND, NN and HD groups (p>0.05, for all). NLR was correlated with night systolic blood pressure (SBP) (r=0.178, p=0.031), night diastolic blood pressure (DBP) (r=0.176, p=0.032) and BP variation rate (r=-0.246, p=0.003). Multiple linear regression analysis showed BP variation rate to be an independent predictor of high NLR value (ß=0.186, 95% CI=0.918-0.982, p=0.044). In ROC analysis, a level of NLR>2.7 predicted non-dipper HT with 83% sensitivity and 65% specificity (ROC area under curve: 0.653, 95% CI=0.565-0.741, p=0.001). CONCLUSION In the present study, we found that NLR levels were significantly correlated with BP variability. The measurement of NLR may be used to indicate increased risk of HT-related adverse cardiovascular events.


Hypertension Research | 2014

The relationship between red-cell distribution width and abnormal left ventricle geometric patterns in patients with untreated essential hypertension

Barış Kılıçaslan; Hüseyin Dursun; Mehmet Aydin; Cenk Ekmekci; Oner Ozdogan

Abnormal left ventricle (LV) geometric patterns are associated with an increased risk of vascular complications of hypertension (HT). The association between red-cell distribution width (RDW) and HT has been recently investigated; however, the relationship between abnormal LV geometric patterns and RDW has not been studied before. The aim of this study was to investigate the relationship between RDW and abnormal LV geometric patterns in patients with untreated essential HT. Measurements were obtained from 139 patients with untreated essential HT (mean age=51.3±16.3 years). Four different geometric patterns (NG, normal geometry; CR, concentric remodeling; EH, eccentric hypertrophy; CH, concentric hypertrophy) were determined according to the LV mass index (LVMI) and relative wall thickness (RWT). RDW, lipid parameters and other biochemical markers were measured in all patients. While the highest RDW values were detected in the CH group (P<0.05, for all), it was similar among the NG, CR and EH groups (P>0.05, for all). RDW was associated with age, LVMI and LV geometry in bivariate analysis (P<0.05, for all). In a receiver operating characteristic (ROC) curve analysis, a level of RDW>14.5 predicted CH with 81% sensitivity and 59% specificity. Age (beta=0.309, P=0.001), LV geometry type (beta=0.228, P=0.01) and RWT (beta=−0.278; P=0.25) were independent predictors of high RDW in multiple linear regression analysis. In conclusion, the highest RDW values were observed in the CH group in the untreated essential HT patients. RDW seems to be a useful tool for the prediction of end-organ damage in patients with untreated essential HT.


Turkish journal of trauma & emergency surgery | 2013

Management of acute myocardial infarction after a blunt chest trauma.

Oner Ozdogan; Mustafa Karacelik; Cenk Ekmekci; Cengiz Ozbek

Coronary artery dissection is a rare complication after blunt chest trauma. Patients usually present with sudden death and the diagnosis is frequently missed. In this report, we present a case of a 46-year-old with a hyperacute anterior wall myocardial infarction after blunt chest trauma. Diagnostic coronary angiography showed total occlusion of the left anterior descending coronary artery (LAD) starting at the takeoff of the vessel from the left main coronary artery (LMCA). A bare-metal stent was immediately deployed at the proximal LAD and TIMI 3 flow was achieved; however post-procedural images revealed no satisfactory results. A proximal dissection and intraluminal thrombus extending to the LMCA was observed. Because of the proximity of the lesion to the LMCA, re-intervention was considered to be risky and urgent coronary artery bypass grafting (CABG) was planned. Coronary artery stenting is the advised treatment modality for coronary occlusion after blunt chest trauma. However, post-traumatic percutaneous coronary intervention was sometimes considered to be risky because of the anatomic features of the lesion. Timing is cardinal in achieving early reperfusion in the course of myocardial infarction after blunt chest trauma and CABG should be the preferred procedure for initial reperfusion treatment especially in proximal LAD dissections with subsequent thrombus formation leading to total occlusion of the artery.


Journal of Cardiovascular Medicine | 2012

Left ventricle-right atrium communication along with a membranous septum aneurysm.

Oner Ozdogan; Cahide Soydas Cinar

At the presentation, the patient was hemodynamically unstable in an anasarcatic state. On physical examination, her blood pressure was 90/65 mmHg. There was no need for mechanical ventilation and inotropic support. Pitting pretibial edema was observed as three plus and the jugular veins were distended. By auscultation, rales in both lung bases, a closing click of the mitral prosthetic valve and grade 4/6 pansystolic murmur were heard with a shudder along the left sternal border. Hepatomegaly was palpable with ascites. Electrocardiography revealed a sinus rhythm with first-degree atrioventricular conduction delay and incomplete right bundle branch block (RBBB). Chest radiograph showed marked cardiomegaly and pulmonary venous congestion. Computed tomography of the thorax showed marked enlargement in the right atrium (RA), right ventricle (RV) and pulmonary artery. An aneurysm in the ventricular membranous septum was also displayed.

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Mehmet Aydin

Mustafa Kemal University

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Ali Basci

University of Toulouse

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