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Dive into the research topics where Osman Bolca is active.

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Featured researches published by Osman Bolca.


Acta Cardiologica | 2007

Effects of folic acid and N-acetylcysteine on plasma homocysteine levels and endothelial function in patients with coronary artery disease

Hale Yılmaz; Sinan Sahin; Nurten Sayar; Burak Tangürek; Mehmet Yilmaz; Zekeriya Nurkalem; Ebru Öntürk; Nazmiye Cakmak; Osman Bolca

Objective — Hyperhomocysteinaemia is related with premature coronary artery disease and adverse cardiac events in patients with coronary artery disease (CAD). It is assumed that hyperhomocysteinaemia causes endothelial dysfunction. In this study, the effect of folic acid and oral N-acetylcysteine (NAC) therapies on plasma homocysteine levels and endothelial function were evaluated in hyperhomocysteinaemic patients with CAD. Methods and results — 60 patients were randomized to either folic acid 5 mg or NAC 600 mg or placebo daily for eight weeks. Brachial artery endothelial functions were studied by using highresolution ultrasound and assessed by measuring endothelium-dependent dilation (EDD) and endothe-lium-independent dilation (NEDD). Folic acid and NAC therapies decreased plasma homocysteine (from 21.7 ± 8.7 jimol/l to 12.5 ± 2.5 jimol/l, P < 0.00l;from 20.9 ± 7.6 jimol/l to 15.6 ± 4.3 jimol/l, P = 0.03, respectively), and increased EDD (6.7 ± 6.1% P = 0.002,4.4 ± 2.6% P < 0.001, respectively) compared with placebo. There was no significant difference in improving EDD between the folic acid and the NAC group (6.7 ± 6.1%, 4.4 ± 2.6%, P = 0.168). In the univariate analyses there was an inverse correlation between the post-treatment homocysteine level and the percent change in EDD with folic acid therapy (r= -0.490, P = 0.028), but there was no correlation with the NAC therapy (r = 0.259, P = 0.333) Conclusions — In patients with hyperhomocysteinaemic CAD, folic acid and NAC lowered plasma homocysteine levels and improved endothelial function.The effects of both treatments in improvement of EDD were similar.


Acta Cardiologica | 2004

The relationship between preprocedural platelet size and subsequent in-stent restenosis.

Tugrul Norgaz; Gultekin Hobikoglu; Huseyin Aksu; Osman Bolca; Huseyin Uyarel; Mehmet Eren; Ahmet Narin

Objective — Elevated mean platelet volume predicts restenosis after percutaneous transluminal coronary angioplasty but its effect on the development of in-stent restenosis is not known. We assessed the effect of mean platelet volume measured before coronary stent implantation for stable angina pectoris on subsequent development of in-stent restenosis. Methods and results — We retrospectively analysed the data of 60 patients who had stent implantation on one native coronary artery for stable angina pectoris and control angiographies for clinically suspected restenosis within 6 months. Mean platelet volume was measured by auto analyzer one day before stent implantation. Clinical and demographic data and laboratory results were obtained from the hospital charts of the patients. In-stent restenosis was evaluated visually from control angiograms.Angiographic in-stent restenosis was present in 35 (58%) of 60 patients and 25 (42%) patients had no restenosis. Mean platelet volume in the in-stent restenosis group was 8.28 ± 0.71 fl compared to 7.63 ± 0.74 fl in the no-restenosis group (p = 0.001).There was a positive correlation between preprocedural mean platelet volume and development of in-stent restenosis (r = 0.44; p < 0.001). A mean platelet volume value of ≥ 8.4 fl was associated with an odds ratio of 16.0 for development of in-stent restenosis, with high specificity and positive predictivity but poor sensitivity and negative predictivity (96%, 93%, 40% and 53%, respectively). Conclusions — Mean platelet volume measured before stent implantation is correlated with subsequent development of in-stent restenosis. If preprocedural mean platelet volume is greater than 8.4 fl, in-stent restenosis is more probable to occur.


American Journal of Emergency Medicine | 2015

Acute myocardial infarction due to marijuana smoking in a young man: guilty should not be underestimated

Yalcin Velibey; Sinan Sahin; Ozan Tanik; Muhammed Keskin; Osman Bolca; Mehmet Eren

Marijuana (cannabis) is a frequently used recreational drug that potentially imposes serious health problems. We present a case of acute myocardial infarction with chronic total occlusion of left main coronary artery due to marijuana smoking in a 27-year-old man, which was not previously reported. This case illustrate that marijuana abuse can lead to serious cardiovascular events.


Journal of Cardiology | 2014

Aortic stiffness is increased in patients with premature coronary artery disease: A tissue Doppler imaging study

Barış Güngör; Hale Yılmaz; Ahmet Ekmekçi; Kazım Serhan Özcan; Mohamedou Tijani; Damirbek Osmonov; Baran Karatas; Ahmet Taha Alper; Ferit Onur Mutluer; Ufuk Gürkan; Osman Bolca

BACKGROUND Atherosclerosis and arterial stiffening may coexist and the correlation of these parameters in patients with premature coronary artery disease (CAD) has not been well elucidated. Tissue Doppler imaging of the ascending aorta may be used in the assessment of elastic properties of the great arteries. OBJECTIVE To investigate the correlation between aortic stiffness and premature CAD using parameters derived from two-dimensional and tissue Doppler imaging (TDI) echocardiography of the ascending aorta. METHODS Fifty consecutive subjects younger than 40 years old who were hospitalized with diagnosis of acute coronary syndrome and had undergone coronary angiography were recruited. The control group included 70 age-sex matched individuals without a diagnosis of CAD. Aortic stiffness index (SI), aortic distensibility (D), and pressure-strain elastic modulus (Ep) were calculated from the aortic diameters measured by two-dimensional M-mode echocardiography and blood pressure obtained by sphygmomanometry. Aortic systolic velocity (SAo), and early (EAo) and late (AAo) diastolic velocities were determined by pulse-wave TDI from the anterior wall of ascending aorta 3cm above the aortic cusps in parasternal long-axis view. RESULTS Stiffness index was higher [median 5.40, interquartile range (IQR) 5.98 vs. median 4.14 IQR 2.43; p=0.03] and distensibility was lower (median 2.86×10(-6)cm(2)/dyn, IQR 2.51×10(-6)cm(2)/dyn vs. median 3.46×10(-6)cm(2)/dyn, IQR 2.38×10(-6)cm(2)/dyn; p=0.04) in patients with CAD compared to the control group. EAo was significantly lower in the CAD group (7.2±1.8cm/s vs. 9.2±2.4cm/s, p<0.01). The difference in EAo remained significant when CAD patients with a left ventricular ejection fraction >55% was compared to the control group. SAo and AAo velocities of ascending aorta were similar in control and CAD groups. There was a significant correlation between EAo velocity and aortic stiffness index (r=-0.28, p=0.01), distensibility (r=0.19, p=0.04) and elastic modulus (r=-0.24, p=0.01). In multivariate regression analysis, decreased levels of high-density lipoprotein cholesterol [odds ratio (OR): 1.12 95% CI 1.06-1.19; p=0.01] and EAo (OR: 1.41 95% CI 1.12-1.79; p=0.01) measurements remained as the variables independently correlated with premature CAD in the study group. CONCLUSION Arterial stiffness is increased in patients with premature CAD. EAo of the anterior wall of ascending aorta measured with pulse-wave TDI echocardiography is correlated with arterial stiffening and is decreased in patients with premature CAD.


American Journal of Emergency Medicine | 2016

Monocyte to high-density lipoprotein ratio as a new prognostic marker in patients with STEMI undergoing primary percutaneous coronary intervention

Mehmet Karatas; Yiğit Çanga; Kazım Serhan Özcan; Göktürk İpek; Barış Güngör; Tolga Onuk; Gündüz Durmuş; Ahmet Öz; Mehmet Ali Karaca; Osman Bolca

BACKGROUND Monocyte count to high-density lipoprotein ratio (MHR) has recently emerged as an indicator of inflammation and oxidative stress in the literature. We aimed to investigate the prognostic value of MHR in patients with ST-segment elevation myocardial infarction treated with primary percutaneous coronary intervention (PCI). METHODS A total of 513 patients who were hospitalized with diagnosis of acute ST-segment elevation myocardial infarction and treated with primary PCI were retrospectively enrolled in the study. Demographic and clinical data, admission laboratory parameters, and MHR values were recorded. Inhospital major adverse cardiac events (MACE) and mortality were reported as the clinical outcomes. RESULTS Twenty-six patients (5%) died, and MACE was observed in 86 patients (17%) during hospital follow-up. Patients were categorized in 3 groups according to tertiles of admission MHR. The rates of inhospital mortality and MACE were significantly higher in tertile 3 group compared to tertile 1 group (10% vs 1%, 27% vs 11%; P < .01 and P < .01). In multivariate regression analysis, age, sex, presence of Killip 3 or 4, left ventricular ejection fraction, troponin I, C-reactive protein, and increased MHR levels (odds ratio, 1.03; 95% confidence interval, 1.01-1.05; P < .01) independently predicted inhospital mortality; age, presence of Killip 3 or 4, troponin I, and increased MHR levels (odds ratio, 1.02; 95% confidence interval, 1.01-1.04; P < .01) independently predicted MACE. CONCLUSION Admission MHR values were found to be independently correlated with inhospital MACE and mortality after primary PCI.


Angiology | 2016

CHA2DS2-VASc Score is a Predictor of No-Reflow in Patients With ST-Segment Elevation Myocardial Infarction Who Underwent Primary Percutaneous Intervention.

Göktürk İpek; Tolga Onuk; Mehmet Karatas; Barış Güngör; Altug Osken; Muhammed Keskin; Ahmet Öz; Ozan Tanik; Mert İlker Hayıroğlu; Hale Yilmaz Yaka; Recep Ozturk; Osman Bolca

Thrombosis and distal embolization play crucial role in the etiology of no-reflow. CHA2DS2-VASc score is used to estimate the risk of thromboembolism in patients with atrial fibrillation. We tested the hypothesis that CHA2DS2-VASc can predict no-reflow among patients who underwent primary percutaneous coronary intervention (PCI). A total number of 2375 consecutive patients with ST-segment elevation myocardial infarction were assessed for the study. Patients were divided into 2 groups as no-reflow (n = 111) and control (n = 1670) groups according to post-PCI no-reflow status. CHA2DS2-VASc scores were calculated for all patients. CHA2DS2-VASc scores were significantly higher in the no-reflow group compared to the control group. After a multivariate regression analysis, CHA2DS2-VASc score remained as an independent predictor (odds ratio: 1.58, 95% confidence interval: 1.33-1,88, P < .001) of no-reflow. Receiver–operating characteristics analysis revealed the cutoff value of CHA2DS2-VASc score ≥2 as a predictor of no-reflow with a sensitivity of 66% and a specificity of 59%. Moreover, in-hospital mortality was also associated with significantly higher CHA2DS2-VASc scores. In conclusion, CHA2DS2-VASc score is associated with higher risk of no-reflow and in-hospital mortality rates in patients who underwent primary PCI.


Coronary Artery Disease | 2015

The neutrophil-to-lymphocyte ratio is associated with bare-metal stent restenosis in STEMI patients treated with primary PCI.

Osman Bolca; Barış Güngör; Kazım Serhan Özcan; Fatma Özpamuk Karadeniz; Aylin Sungur; Bayram Köroğlu; Nijad Bakhshyaliyev; Nizamettin Selçuk Yelgeç; Baran Karatas; Göktürk İpek; Hale Yılmaz; Recep Ozturk

BackgroundThe clinical importance of complete blood count (CBC) parameters such as the neutrophil-to-lymphocyte ratio (NLR) has been shown in cardiovascular diseases. Stent restenosis (SR) is a major adverse event after stent implantation. In this study, we aimed to investigate the correlation of CBC parameters with SR rates after primary percutaneous coronary intervention (PCI). MethodsPatients who had undergone primary PCI for ST-segment elevation myocardial infarction (STEMI) and control angiography during follow-up were retrospectively recruited. Patients were categorized according to admission NLR tertiles, and clinical, hematological, and angiographic data were compared. ResultsA total of 404 patients (207 patients with SR and 197 patients without SR) were included in the study. Patients were categorized into three groups according to the tertiles of admission NLRs; the NLR was less than 3.38 in tertile 1 (n=134), between 3.38 and 6.26 in tertile 2 (n=135), and greater than 6.26 in tertile 3 (n=135). During a follow-up period of a median of 14 months (minimum 6 months, maximum 60 months) SR developed in 80 patients of tertile 3 (59%), 74 patients of tertile 2 (55%), and 53 patients of tertile 1 (40%), which were significantly different (P=0.01). According to multivariate Cox regression analysis, male sex, stent length (odds ratio 1.04, 95% confidence interval 1.01–1.06, P=0.01), admission NLRs (odds ratio 1.13, 95% confidence interval 1.08–1.19, P=0.01), and white blood cell and neutrophil counts remained the independent predictors of SR in the study population. Other CBC parameters and admission C-reactive protein, creatinine, and fasting glucose levels were not independently correlated with SR. On receiver operating curve analysis, admission NLRs higher than 3.84 were found to predict SR with a sensitivity of 73.4% and a specificity of 50.8% (area under the curve 0.604, P=0.01). ConclusionHigh NLR levels, white blood cell counts, and neutrophil counts at admission are independently correlated with SR after primary PCI.


Coronary Artery Disease | 2016

Association of admission serum laboratory parameters with new-onset atrial fibrillation after a primary percutaneous coronary intervention.

Mehmet Karatas; Yiğit Çanga; Göktürk İpek; Kazım Serhan Özcan; Barış Güngör; Gündüz Durmuş; Tolga Onuk; Ahmet Öz; Bariş Şimşek; Osman Bolca

ObjectivesNew-onset atrial fibrillation (NOAF) during hospitalization is considered a frequent complication associated with worse outcomes in the setting of ST-segment elevation myocardial infarction (STEMI). We aimed to investigate the association of admission serum laboratory parameters, neutrophil to lymphocyte ratio (NLR), and monocyte to high-density lipoprotein ratio (MHR) with NOAF in STEMI patients treated with a primary percutaneous coronary intervention (PCI). Patients and methodsA total of 621 patients who were hospitalized with a diagnosis of STEMI and treated with primary PCI were retrospectively enrolled in the study. NOAF during index hospitalization and overall mortality were reported as the clinical outcomes. ResultsIn our study population, 40 (6.4%) patients developed NOAF during index hospitalization. Monocyte counts, mean platelet volume (MPV), red cell distribution width (RDW), NLR, MHR, C-reactive protein (CRP), creatinine, glucose, and uric acid levels were higher in the NOAF+ group compared with the NOAF− group. In multivariate regression analysis, age, left-ventricular ejection fraction, left atrial volumes, admission heart rate, multivessel disease, increased levels of CRP, MPV, RDW, uric acid, NLR, and MHR independently predicted NOAF. In addition, NOAF was found to be an independent predictor of overall mortality in the study population. ConclusionFor the first time in the literature, admission serum levels of MPV, RDW, uric acid, NLR, and MHR were found to be correlated independently with NOAF after primary PCI.


Kardiologia Polska | 2014

The presence of fragmented QRS on 12-lead ECG in patients with coronary slow flow.

Hale Yılmaz; Barış Güngör; Tuğba Kemaloğlu; Nurten Sayar; Betul Erer; Mehmet Yilmaz; Nazmiye Çakmak; Ufuk Gürkan; Dilaver Oz; Osman Bolca

BACKGROUND Coronary slow flow (CSF) is characterised by delayed opacification of coronary arteries in the absence of epicardial occlusive disease. It has been reported that CSF may cause angina, myocardial ischaemia, and infarction. Fragmentation of QRS complex (fQRS) is an easily evaluated non-invasive electrocardiographic parameter. It has been associated with alternation of myocardial activation due to myocardial scar and/or ischaemia. Whether CSF is associated with fQRS is unknown. The presence of fQRS on ECG may be an indicator of myocardial damage in patients with CSF. AIM To investigate the presence of fQRS in patients with CSF. METHODS Sixty patients (mean age 55.5 ± 10.5 years) with CSF and 44 patients with normal coronary arteries without associated CSF (mean age 53 ± 8.4 years) were included in this study. The fQRS was defined as the presence of an additional R wave or notching of R or S wave or the presence of fragmentation in two contiguous leads corresponding to a major coronary artery territory. RESULTS The presence of fQRS was higher in the CSF group than in the controls (p = 0.005). Hypertension was significantly more common in the CSF group (p < 0.001). There was no significant association between the presence of fQRS and an increasing number of vessel involvements. Logistic regression analysis demonstrated that the presence of CSF was the independent determinant of fQRS (OR = 10.848; 95% CI 2.385-49.347; p = 0.002). CONCLUSIONS Fragmented QRS, indicating increased risk for arrhythmias and cardiovascular mortality, was found to be significantly higher in patients with CSF. We have not found an association between the presence of fragmented QRS and the degree of CSF. Further prospective studies are needed to establish the significance as a possible new risk factor in patients with CSF.


European Journal of Heart Failure | 2002

Prognostic implication of myocardial texture analysis in idiopathic dilated cardiomyopathy.

Bahadir Dagdeviren; Osman Akdemir; Mehmet Eren; Osman Bolca; Enis Oguz; Yekta Gurlertop; Tuna Tezel

Abnormal myocardial acoustic properties have been reported in patients with idiopathic dilated cardiomyopathy (IDC). The aim of this study was to investigate the relationship between quantitative ultrasonic textural alterations of myocardium and clinical outcome in IDC.

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Göktürk İpek

Brigham and Women's Hospital

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Tolga Onuk

Zonguldak Karaelmas University

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