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Dive into the research topics where Ali Kemal Kalkan is active.

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Featured researches published by Ali Kemal Kalkan.


Gene | 2016

Circulating miR-221-3p as a novel marker for early prediction of acute myocardial infarction.

Ender Coskunpinar; Huseyin Altug Cakmak; Ali Kemal Kalkan; Necip Ozan Tiryakioglu; Mehmet Erturk; Zeki Öngen

Recent studies have reported circulating microRNAs (miRNAs) as novel biomarkers for cardiovascular diseases including acute myocardial infarction, heart failure, diabetes mellitus, stroke, and acute pulmonary embolism. The aims of this study were 1) to compare the plasma expression levels of miRNAs in patients with acute coronary syndrome (ACS) and control subjects and in ST-elevation myocardial infarction (STEMI) and non-STEMI 2) to evaluate miRNAs potential to be used as novel diagnostic biomarkers for ACS. Twenty seven consecutive patients, admitted to emergency department of a training and research hospital between January-December 2013 with acute chest pain and/or dyspnea and diagnosed with ACS, and 16 non-ACS control subjects were included in this study. miRNA profiling was performed by using real time polymerase chain reaction. Functions of dysregulated miRNAs were evaluated by computerized-pathways analysis. miR-221-3p was one of the two most dysregulated miRNAs with a fold regulation of 3.89. It was significantly positively correlated with both Troponin and GRACE and Synthax Score. Moreover, miR221-3p was found to be significantly inversely correlated with left ventricular ejection fraction. miR-221-3p was the most prominent biomarker candidate with an area under curve (AUC) level of 0.881 (95% confidence interval: 0.774-0.987; p=0.002). The present study is the first to report an increased expression levels of miR-221-3p in AMI. Since miR-221-3p has a high discriminative value and significant relations with Troponin, GRACE and Synthax score and left ventricular systolic function, it may be a potential biomarker for early prediction of AMI.


International Journal of Cardiology | 2014

Cerebral microemboli and neurocognitive change after carotid artery stenting with different embolic protection devices

Emre Akkaya; Ertan Vuruskan; Zeynep Bastug Gul; Aydin Yildirim; Hamdi Pusuroglu; Ozgur Surgit; Ali Kemal Kalkan; Ozgur Akgul; Gamze Pinar Akgul; Mehmet Gul

OBJECTIVES Proximal cerebral protection devices have been developed as an alternative to filter protection devices for reducing neurological complications during carotid artery stenting (CAS). The aim of the present study was to evaluate the frequency of silent cerebral embolism after CAS using different cerebral embolic protection devices and the impact of silent cerebral embolism on neurocognitive function. METHODS One hundred consecutive patients who underwent CAS were enrolled. The patients were randomized to either proximal balloon occlusion or filter protection. Neurocognitive tests were performed before and six months after CAS. Cerebral embolisms were evaluated with diffusion-weighted magnetic resonance imaging (DW-MRI). RESULTS The number and volume of new ischemic lesions found with DW-MRI were higher in the filter protection group than in the proximal balloon occlusion group. According to our definition, nine (21%) patients in the balloon occlusion group and 16 (36%) patients in the filter protection group showed neurocognitive decline, and ten (23%) patients in the balloon occlusion group and four (9%) patients in the filter protection group showed neurocognitive improvement (NS). Regarding the group of patients with new cerebral ischemic lesions on DW-MRI, neurocognitive decline occurred in 14 (31%) of 45 patients with DW-MRI lesions and 11 (26%) of 43 patients without DW-MRI lesions (NS). CONCLUSION Neurocognitive outcome after CAS is unpredictable; both neurocognitive decline and improvement can occur. In this study, the proximal balloon occlusion system significantly decreased cerebral microemboli during CAS compared to filter protection. Cerebral microembolism was not found to be associated with neurocognitive decline.


International Journal of Cardiology | 2009

Acute myocardial infarction in a 24 year-old man possibly associated with sibutramine use

Elif Eroglu; Gökmen Gemici; Fatih Bayrak; Ali Kemal Kalkan; Muzaffer Degertekin

Sibutramine is an anti-obesity drug, which acts by inhibiting neuronal re-uptake of noradrenaline and serotonin. Although the most frequently seen effect of sibutramine on cardiovascular system is an increase in blood pressure and pulse rate, rare but severe side effects such as sibutramine-induced ventricular arrhythmias, heart failure and cardiovascular disease-related death are also reported. We describe a 24 year-old man with low atherosclerotic risk profile who had acute myocardial infarction possibly associated with sibutramine use.


Echocardiography-a Journal of Cardiovascular Ultrasound and Allied Techniques | 2009

Chronic Cigarette Smoking Affects Left and Right Ventricular Long‐Axis Function in Healthy Young Subjects: A Doppler Myocardial Imaging Study

Elif Eroglu; Sinan Aydın; Firat Yalniz; Ali Kemal Kalkan; Fatih Bayrak; Muzaffer Degertekin

Objective: Cigarette smoking is one of the major risk factors for coronary artery disease. However, chronic smoking has additional cardiac adverse effects independent of coronary atherosclerosis. We assessed the possible effects of chronic smoking on left and right ventricular (LV, RV) long‐axis function using Doppler myocardial imaging (DMI). Methods: Forty otherwise healthy smokers (mean age = 26±3 years) and 40 age‐matched nonsmoking controls enrolled. Standard echocardiography protocol was followed by DMI. Peak systolic (VS), early (VE) and late diastolic (VA) velocities, peak systolic strain (S), and strain rate (SR) were measured from septal, lateral, and RV free walls. Results: The baseline characteristics of two groups were similar. There were significant differences regarding Doppler myocardial velocity, S, and SR indices. Septal VE (P < 0.04), S (P < 0.0001) and SR (P < 0.02) were significantly reduced in smokers. For both lateral and RV free wall, VS (P < 0.003, P < 0.002, respectively), VE (P < 0.0001, P < 0.002, respectively), S (P < 0.0001 for both), and SR (P < 0.0001, P < 0.002, respectively) were significantly reduced in smokers. There were significant correlations between the amount of smoking and septal, lateral, and RV free wall S and SR. Conclusions: Chronic cigarette smoking causes alterations in long‐axis systolic and diastolic functions of right and left ventricles in healthy young subjects. These changes can be accurately detected with Doppler myocardial velocity and SR imaging.


Annals of Noninvasive Electrocardiology | 2015

The Assessment of Relationship between Fragmented QRS Complex and Left Ventricular Wall Motion Score Index in Patients with ST Elevation Myocardial Infarction Who Underwent Primary Percutaneous Coronary Intervention

Nevzat Uslu; Mehmet Gül; Huseyin Altug Cakmak; Ali Atam; Hamdi Pusuroglu; Hulusi Satılmışoğlu; Emre Akkaya; Hale Unal Aksu; Ali Kemal Kalkan; Ozgur Surgit; Mehmet Erturk; Hüseyin Aksu; Abdurrahman Eksik

Fragmented QRS (fQRS) has been found to be associated with high mortality and arrhythmic events in acute coronary syndromes. Regional systolic function using wall motion score index (WMSI) is an alternative to left ventricular ejection fraction (LVEF) for the assessment of left ventricular systolic function. The aim of this study was to investigate the relation between the presence of fQRS on admission electrocardiogram (ECG) and WMSI in ST elevation myocardial infarction (STEMI) underwent primary coronary intervention (PCI). The in‐hospital and long‐term prognostic significance of persistent fQRS was also evaluated.


international conference on medical imaging and augmented reality | 2010

Manifold learning for image-based gating of intravascular ultrasound (IVUS) pullback sequences

Gozde Gul Isguder; Gözde B. Ünal; Martin Groher; Nassir Navab; Ali Kemal Kalkan; Muzaffer Degertekin; Holger Hetterich; Johannes Rieber

Intravascular Ultrasound(IVUS) is an imaging technology which provides cross-sectional images of internal coronary vessel structures. The IVUS frames are acquired by pulling the catheter back with a motor running at a constant speed. However, during the pullback, some artifacts occur due to the beating heart. These artifacts cause inaccurate measurements for total vessel and lumen volume and limitation for further processing. Elimination of these artifacts are possible with an ECG (electrocardiogram) signal, which determines the time interval corresponding to a particular phase of the cardiac cycle. However, using ECG signal requires a special gating unit, which causes loss of important information about the vessel, and furthermore, ECG gating function may not be available in all clinical systems. To address this problem, we propose an image-based gating technique based on manifold learning. Quantitative tests are performed on 3 different patients, 6 different pullbacks and 24 different vessel cuts. In order to validate our method, the results of our method are compared to those of ECG-Gating method.


Canadian Journal of Cardiology | 2016

Utility of the Logistic Clinical Syntax Score in the Prediction of Contrast-Induced Nephropathy After Primary Percutaneous Coronary Intervention.

Derya Ozturk; Omer Celik; Mehmet Erturk; Ali Kemal Kalkan; Fatih Uzun; Ibrahim Faruk Akturk; Fatih Akın; Aydin Yildirim

BACKGROUND The Logistic Clinical Syntax Score (log CSS) is a combined risk scoring system that includes clinical and anatomic parameters; it has been found to be effective for the prediction of mortality in patients with ST-elevation myocardial infarction (STEMI). The aim of the present study was to assess whether the log CSS was associated with the development of contrast-induced nephropathy (CIN) in patients who underwent primary percutaneous coronary intervention (pPCI). METHODS A total of 930 patients with STEMI undergoing pPCI between January 2012 and August 2013 were included prospectively. The patients were grouped according to the development of CIN. Either an absolute serum creatinine level ≥ 0.5 mg/dL or a 25% increase in the serum creatinine level compared with the baseline level within 48 hours after the administration of contrast medium was defined as CIN. RESULTS The Synergy Between Percutaneous Coronary Interventions With Taxus and Cardiac Surgery score (SYNTAX [SS]) and log CSS were higher in patients with CIN than in those without. In the multivariate analysis, log CSS (odds ratio, 1.405, 95% confidence interval, 1.318-1.497; P < 0.001), hemoglobin, and contrast volume were found to be independent predictors of CIN. In the receiver operating characteristic analysis, a log CSS > 9.5 had a 74.5% sensitivity and a 90.5% specificity for predicting CIN, with an area under the curve (AUC) of 0.892, whereas an SS > 18.5 had a 64% sensitivity, a 58.1% specificity, and an AUC of 0.625 (0.892 vs 0.625; P < 0.001). A log CSS > 9.5 was associated with in-hospital and long-term mortality, reinfarction, revascularization, and in-hospital hemodialysis (P < 0.001 for each). CONCLUSIONS The log CSS may improve the accuracy of risk stratification for the development of CIN in patients undergoing pPCI.


Perfusion | 2017

Neutrophil to lymphocyte ratio: a novel marker for predicting hospital mortality of patients with acute type A aortic dissection:

Mehmet Emin Kalkan; Ali Kemal Kalkan; Ahmet Gündeş; Mehmed Yanartaş; Semi Ozturk; Ahmet Seyfeddin Gurbuz; Derya Ozturk; Taner Iyigun; Mustafa Akçakoyun; Mehmet Yunus Emiroglu; Mehmet Altuğ Tuncer; Cengiz Koksal

Introduction: The inflammatory process has been reported to be associated with aortic dissection (AD) from the development to the prognosis. The aim of the study was to investigate a relationship between the neutrophil to lymphocyte ratio (NLR) and in-hospital outcomes in patients with acute aortic dissection (AAD) who underwent surgical repair. Methods: One hundred and eighty-four patients who were admitted with the diagnosis of type A AAD who underwent surgical repair at two large tertiary hospitals. According to their NLR, 91 patients had high NLR (>6.0) and 93 patients had low NLR (⩽6.0). Results: The frequency of major bleeding, hospital-related infection, multi-organ dysfunction and mortality in hospital were higher in the high NLR group compared to the low NLR group. NLR, WBC count and operation duration were found to be independent predictors for in-hospital mortality. Conclusions: The novel inflammatory marker NLR may be used to predict worse outcomes and hospital mortality in patients with AAD treated by surgical repair.


Cardiology Journal | 2015

Assessment of the relationship between a narrow fragmented QRS complex and coronary slow flow

Huseyin Altug Cakmak; Serkan Aslan; Mehmet Gül; Ali Kemal Kalkan; Derya Ozturk; Omer Celik; Omer Tasbulak; Muhammet Hulusi Satilmisoglu

BACKGROUND The coronary slow flow (CSF) phenomenon is a delayed antegrade progression of contrast agent to the distal branch of a coronary artery in the absence of obstructive coronary artery disease (CAD). A narrow fragmented QRS (fQRS) has been reported as a significant predictor of sudden cardiac death in patients with idiopathic dilated cardiomyopathy. The present study aimed to investigate the relationship between a narrow fQRS on the admission electrocardiogram (ECG) and CSF on coronary angiography. METHODS This study included 165 consecutive patients (112 CSF, 53 controls) who underwent first-time diagnostic conventional coronary angiography for suspected CAD. Coronary flow was quantified by thrombolysis in myocardial infarction (TIMI) frame count (TFC). The patients were divided into two groups according to the presence or absence of a narrow fQRS complex on the admission ECG. RESULTS Forty four patients were in the fQRS group (mean age, 52.97 ± 3.13 years). There was no difference between the two groups with respect to age, gender, body mass index, family history, hyperlipidemia, hypertension, or diabetes mellitus. The extent of CSF was significantly greater in the fQRS group compared to the non-fragmented group (p < 0.001). A significant correlation was also found between mean TFC values and fQRS (p < 0.001). On multivariate analysis, only CSF (p = 0.03) was a significant independent predictor for narrow fQRS, after adjustment for other parameters. CONCLUSIONS The narrow fQRS is a simple, inexpensive, and readily available noninvasive ECG parameter that may be a new potential indicator of myocardial damage in patients with CSF.


Acta Cardiologica | 2016

Assessment of sustained effects of levosimendan on right ventricular systolic functions in patients with advanced heart failure.

Aslı Kurtar Mansıroglu; Ender Oner; Mehmet Erturk; Huseyin Karakurt; Mustafa Umut Somuncu; Ali Birant; Ali Kemal Kalkan; Derya Ozturk; Abdurrahman Eksik

Background Poor right ventricular function is an independent prognostic marker for mortality in heart failure patients. Echocardiographic studies concerning effects of levosimendan on right ventricular function performed second measurements just after or 24 hours after levosimendan infusion. We aimed to detect sustained effects of levosimendan infusion on right ventricular systolic function. Method The study consisted of 47 patients with acutely decompensated heart failure with NYHA class III or IV symptoms. Levosimendan was infused for 24 hours. Before and 5 days after the initiation of infusions, functional class was assessed, NT-proBNP levels and LVEF, RVEF, using tissue Doppler imaging, RV isovolumic myocardial acceleraton (IVA), peak myocardial velocity during isovolumic contraction (IVV), peak systolic velocity during ejection period (Sa), early (E’) and late (A’) diastolic velocities, and E’/A’ ratio were measured. Results NYHA class improved and NT-proBNP levels were significantly reduced. LVEF and RVEF also improved significantly. Tissue Doppler-derived systolic indices of IVV and IVA increased and RV diastolic indices improved. Conclusion Improvements in RV systolic and diastolic functions continue after levosimendan infusion as expressed by conventional echocardiographic and TDI-derived parameters in patients with acute decompensated HF.

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Muzaffer Degertekin

Erasmus University Rotterdam

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