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Dive into the research topics where Gültekin Karakus is active.

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Featured researches published by Gültekin Karakus.


Echocardiography-a Journal of Cardiovascular Ultrasound and Allied Techniques | 2010

Effects of Isolated Obesity on Left and Right Ventricular Function: A Tissue Doppler and Strain Rate Imaging Study

Ahmet L. Orhan; Nevzat Uslu; Sennur Unal Dayi; Zekeriya Nurkalem; Fatih Uzun; Hatice Betül Erer; Hakan Hasdemir; Ayse Emre; Gültekin Karakus; Ozlem Soran; John Gorcsan; Mehmet Eren

Objective: To determine the subclinical effects of isolated obesity and its duration on cardiac function by using routine echocardiography and tissue Doppler myocardial strain rate. Methods: Forty‐nine subjects were enrolled in this study; 29 with isolated obesity defined as a body mass index ≥30 kg/m2 with no other cardiovascular comorbidities, and 20 nonobese controls. All subjects underwent two‐dimensional and Doppler echocardiography including tissue Doppler imaging and myocardial strain rate. Results: The average duration of obesity was 12.1 years (4–18 years). Abnormalities of left ventricular (LV) wall thickness, mass, diastolic function, and left atrial size were detected in obese individuals, despite having preserved ejection fractions. The LV global longitudinal peak strain rate was significantly lower in obese subjects compared to nonobese control subjects (1.07 ± 0.14 vs. 1.38 ± 0.12, P < 0.001). Using multivariate analysis, the duration of obesity (ß=−0.76, P < 0.001), body mass index (ß=−0.35, P = 0.023), and age (ß=−0.29, P = 0.009) were independent predictors of the decreased LV global longitudinal peak strain rate, while the duration of obesity (ß=−0.66, P < 0.001) and body mass index (ß=−0.28, P = 0.037) were independent predictors of the decreased right ventricular (RV) peak strain rate. Conclusion: The presence and the duration of obesity were associated with impairment of subclinical biventricular systolic and diastolic function. These findings have the potential to increase awareness of subclinical cardiac manifestations in patients with isolated obesity and influence their early management. (Echocardiography 2010;27:236‐243)


Echocardiography-a Journal of Cardiovascular Ultrasound and Allied Techniques | 2008

Comparative assessment of left atrial appendage by transesophageal and combined two- and three-dimensional transthoracic echocardiography.

Gültekin Karakus; Visali Kodali; Vatsal Inamdar; Navin C. Nanda; Thouantosaporn Suwanjutah; Koteswara R. Pothineni

Objective: Our objective was to compare the utility of combined two‐dimensional (2D) transthoracic echocardiography (TTE) and three‐dimensional (3D) TTE versus 2D transesophageal echocardiography (TEE) in evaluation of the left atrium (LA) and LA appendage (LAA) for clot. Background: 2DTEE, usually performed to visualize the LAA, is semi‐invasive and not without risks. With improved technology the LAA has been increasingly visualized by 2DTTE and 3DTTE in many patients. Methods: We compared combined 2DTTE and 3DTTE with 2DTEE in evaluating the LA/LAA for a thrombus. Ninety‐two patients underwent 2DTTE, 3DTTE, and 2DTEE. An additional 20 patients, in whom TEE could not be performed, underwent 2DTTE and 3DTTE. Results: LA and LAA could be visualized in all patients. Of 92 patients studied, 74 had no thrombus and 7 had thrombus in the LAA by all modalities. Eleven patients, 9 with atrial fibrillation (AF), had a suspected thrombus by 2DTEE, but 3DTTE cropping clearly showed these to be prominent pectinate muscles which were seen in short axis on 2DTEE as rounded echo dense masses and therefore mimicked thrombi. These 9 patients with AF underwent successful cardioversion without any complications. Of the 20 patients in whom TEE could not be performed, 19 had no thrombus in the LA/LAA and 1 had a clot in the LAA. These 19 patients underwent successful cardioversion without complications. Conclusions: Our preliminary study suggests that combined 2DTTE and 3DTTE has comparable accuracy to TEE in evaluating the LA and LAA for thrombus. In some patients TEE, but not 3DTTE, may misdiagnose pectinate musculature as thrombus.


Echocardiography-a Journal of Cardiovascular Ultrasound and Allied Techniques | 2008

Effect of Alcohol-Induced Septal Ablation on Left Atrial Volume and Ejection Fraction Assessed by Real Time Three-Dimensional Transthoracic Echocardiography in Patients with Hypertrophic Cardiomyopathy

Fadi G. Hage; Gültekin Karakus; William D. Luke; Thouantosaporn Suwanjutah; Navin C. Nanda; Raed A. Aqel

Alcohol‐induced septal ablation (AISA) is an accepted treatment for hypertrophic cardiomyopathy (HCM) patients with left ventricular (LV) outflow obstruction who are unresponsive to medical therapy. As left atrial (LA) enlargement has been correlated with increased morbidity and mortality in HCM, we assessed LA volumes and ejection fraction (EF) prior to and after AISA using real time three‐dimensional (3D) transthoracic echocardiography (TTE) in 12 patients (9 women; mean age 52 ± 15 years; 11 Caucasian). All patients underwent successful AISA with no complications and their resting left ventricular outflow gradients decreased from 40.5 ± 22.2 to 9.1 ± 17.6 mmHg (P < 0.001) while their gradients with provocation decreased from 126.2 ± 31.7 to 21.8 ± 28.0 mmHg (P < 0.001). All patients showed improvements in their New York Heart Association (NYHA) functional class. Both the LA end‐systolic (45.2 ± 12.9 to 37.2 ± 13.7 ml, P < 0.0001) and end‐diastolic (79.6 ± 18.9 to 77.1 ± 18.6 ml, P = 0.001) volumes decreased after AISA. The LA EF increased from 43.1 ± 9.0 to 52.5 ± 8.8% (P = 0.001). The increase in LA EF correlated with the decrease in the resting left ventricular outflow gradient (R =−0.647, P = 0.03). In conclusion, 3D echocardiography can be utilized to follow LA function after AISA for HCM. AISA results in clinical improvement in patients with HCM and in improvement of LA EF that is correlated with the decrease in the left ventricular outflow gradient.


The Cardiology | 2015

Comparison of Effects of Low- versus High-Dose Heparin on Access-Site Complications during Transradial Coronary Angiography: A Double-Blind Randomized Study

Aleks Degirmencioglu; Ertuğrul Zencirci; Gültekin Karakus; Tolga Sinan Güvenç; Ahmet Akyol; Aycan Esen; Yasemin Demirci; Ilke Sipahi; Sinan Dagdelen; Tugrul Norgaz; Sevket Gorgulu

Objectives: Although heparin is highly effective in reducing the rate of radial artery occlusion after transradial catheterization, the optimal heparin dose is still controversial. The aim of this study was to evaluate the efficacy and safety of two different heparin doses during transradial coronary angiography. Methods: 490 consecutive patients undergoing transradial coronary angiography were prospectively enrolled into this double-blind randomized trial. A total of 202 patients enrolled in the low-dose (LD; 2,500 U of heparin) group and 202 patients enrolled in the high-dose (HD; 5,000 U of heparin) group were included in the final analysis. The primary endpoint of the study was radial artery occlusion. Bleeding and hematomas were the secondary outcome measures. Results: At day 7, radial artery occlusion occurred in 5.9% of the patients in the LD group and in 5.4% of the patients in the HD group (p = 0.83). Bleeding during deflation of the transradial band occurred in 6.4% of the patients in the LD group and in 18.3% of the patients in the HD group; the difference was statistically significant (p < 0.001). Higher-dose heparin was found to be an independent predictor of bleeding (p = 0.007). Conclusion: A lower dose of heparin (i.e. 2,500 U) decreases bleeding during transradial band deflation without an increase in radial artery occlusion.


Echocardiography-a Journal of Cardiovascular Ultrasound and Allied Techniques | 2008

Transthoracic Doppler echocardiographic coronary flow imaging in identification of left anterior descending coronary artery stenosis in patients with left bundle branch block.

Ozer Soylu; Seden Celik; Gültekin Karakus; Aydin Yildirim; Mehmet Ergelen; Ertuğrul Zencirci; Hüseyin Aksu; Tuna Tezel

Background: Conventional noninvasive methods have well‐known limitations for the detection of coronary artery disease (CAD) in patients with left bundle branch block (LBBB). However, advancements in Doppler echocardiography permit transthoracic imaging of coronary flow velocities (CFV) and measurement of coronary flow reserve (CFR). Our aim was to evaluate the diagnostic value of transthoracic CFR measurements for detection of significant left anterior descending (LAD) stenosis in patients with LBBB and compare it to that of myocardial perfusion scintigraphy (MPS). Methods: Simultaneous transthoracic CFR measurements and MPS were analyzed in 44 consecutive patients with suspected CAD and permanent LBBB. Typical diastolic predominant phasic CFV Doppler spectra of distal LAD were obtained at rest and during a two‐step (0.56–0.84 mg/kg) dipyridamole infusion protocol. CFR was defined as the ratio of peak hyperemic velocities to the baseline values. A reversible perfusion defect at LAD territory was accepted as a positive scintigraphy finding for significant LAD stenosis. A coronary angiography was performed within 5 days of the CFR studies. Results: The hyperemic diastolic peak velocity (44 ± 9 cm/sec vs 62 ± 2 cm/sec; P=0.01) and diastolic CFR (1.38 ± 0.17 vs 1.93 ± 0.3; P=0.001) were significantly lower in patients with LAD stenosis compared to those without LAD stenosis. The diastolic CFR values of <1.6 yielded a sensitivity of 100% and a specificity of 94% in the identification of significant LAD stenosis. In comparison, MPS detected LAD stenosis with a sensitivity of 100% and a specificity of 29%. Conclusions: CFR measurement by transthoracic Doppler echocardiography is an accurate method that may improve noninvasive identification of LAD stenosis in patients with LBBB.


Nephron Clinical Practice | 2014

Efficacy of Oral Hydration in the Prevention of Contrast-Induced Acute Kidney Injury in Patients Undergoing Coronary Angiography or Intervention

Sukru Akyuz; Mehmet Karaca; Tuğba Kemaloğlu Öz; Servet Altay; Barış Güngör; Barış Yaylak; Selçuk Yazıcı; Kıvılcım Özden; Gültekin Karakus; Nese Cam

Background: Efficacy of intravenous (IV) volume expansion in preventing contrast-induced acute kidney injury (CI-AKI) is well known. However, the role of oral hydration has not been well established. The aim of this work was to evaluate the efficacy of oral hydration in preventing CI-AKI. Methods: We prospectively randomized 225 patients undergoing coronary angiography and/or percutaneous coronary intervention in either oral hydration or IV hydration groups. Patients who have at least one of the high-risk factors for developing CI-AKI (advanced age, type 2 diabetes mellitus, anemia, hyperuricemia, a history of cardiac failure or systolic dysfunction) were included in the study. All patients had normal renal function or stage 1-2 chronic kidney disease. Patients in the oral hydration group were encouraged to drink unrestricted amounts of fluids freely whereas isotonic saline infusion was performed by the standard protocol in the IV hydration group. Results: CI-AKI occurred in 8/116 patients (6.9%) in the oral hydration group and 8/109 patients (7.3%) in the IV hydration group (p = 0.89). There was also no statistically significant difference between the two groups when different CI-AKI definitions were taken into account. Conclusion: Oral hydration is as effective as IV hydration in preventing CI-AKI in patients with normal kidney function or stage 1-2 chronic kidney disease, and who also have at least one of the other high-risk factors for developing CI-AKI.


Cardiology Journal | 2012

Comparison of mean platelet volume values among different causes of pulmonary hypertension

Tolga Sinan Güvenç; Hatice Betül Erer; Sami Ilhan; Gönül Zeren; Erkan İlhan; Gültekin Karakus; Nurten Sayar; Ahmet Lütfi Orhan; Mehmet Eren

BACKGROUND Pulmonary hypertension is caused by a heterogenous group of disorders with diverse pathophysiological mechanisms, with ultimate structural changes in the pulmonary vascular bed. Platelet activation plays an important role in the development of pulmonary arterial hypertension, while it is unknown whether it contributes to pathogenesis in other conditions. We aimed to investigate platelet activation in different causes of pulmonary hypertension by means of mean platelet volume measurement. METHODS A total of 67 patients with different causes of pulmonary hypertension, and 31 controls, were retrospectively reviewed. Patients with pulmonary hypertension were further grouped according to underlying disease, including pulmonary arterial hypertension, pulmonary hypertension due to left ventricular failure, and pulmonary hypertension due to chronic obstructive pulmonary disorder. All patients and controls past medical data, admission echocardiograms and complete blood counts were reviewed. RESULTS Patients with pulmonary hypertension had higher mean platelet volume levels compared to healthy controls (8.77 ± 1.18 vs 7.89 ± 0.53; p < 0.001), and statistical significance was still present when pulmonary arterial hypertension patients were not included in the pulmonary hypertension group (8.59 ± 1.23 vs 7.89 ± 0.53; p < 0.001). Among patients with pulmonary hypertension, the pulmonary arterial hypertension group and the pulmonary hypertension due to left ventricular failure group had higher mean platelet volumes compared to healthy controls. Mean platelet volume did not correlate with pulmonary artery pressure. CONCLUSIONS Our results indicate that mean platelet volume is not only elevated in pulmonary arterial hypertension, but also due to other causes of pulmonary hypertension.


Korean Circulation Journal | 2015

The Association between Subclinical Hypothyroidism and Epicardial Adipose Tissue Thickness

Erdal Belen; Aleks Degirmencioglu; Ertuğrul Zencirci; Fatih Fahri Tipi; Özgür Altun; Gültekin Karakus; Aysen Helvaci; Aycan Esen Zencirci; Ezgi Kalaycıoğlu

Background and Objectives Subclinical hypothyroidism (SH) is considered to be a potential risk factor for cardiovascular disease. Epicardial adipose tissue (EAT) thickness is also closely related to cardiovascular disorders. The aim of this study was to evaluate whether SH is associated with higher EAT thickness. Subjects and Methods Fifty-one consecutive patients with SH and 51 healthy control subjects were prospectively enrolled into this trial. Thyroid hormone levels, lipid parameters, body mass index, waist and neck circumference, and EAT thickness measured by echocardiography were recorded in all subjects. Results Mean EAT thickness was increased in the SH group compared to the control group (6.7±1.4 mm vs. 4.7±1.2 mm, p<0.001). EAT thickness was shown to be correlated with thyroid stimulating hormone level (r=0.303, p=0.002). Multivariate logistic regression analysis revealed that EAT thickness was independently associated with SH {odds ratio (OR): 3.87, 95% confidence interval (CI): 1.92-7.78, p<0.001; OR: 3.80, 95% CI: 2.18-6.62, p<0.001}. Conclusion Epicardial adipose tissue thickness is increased in patients with SH compared to control subjects, and this increase in EAT thickness may be associated with the potential cardiovascular adverse effects of SH.


Kardiologia Polska | 2014

The relationship between Gensini score and ST-segment resolution in patients with acute ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention

Aycan Esen Zencirci; Ertuğrul Zencirci; Aleks Degirmencioglu; Gültekin Karakus; Murat Ugurlucan; Sabahattin Gündüz; Kıvılcım Özden; Aysun Erdem; Fatma Özpamuk Karadeniz; Ahmet Ekmekçi; Hatice Betül Erer; Nurten Sayar; Mehmet Eren

BACKGROUND Clinical outcomes of patients with myocardial infarction are primarily determined by the successful restoration of myocardial reperfusion and the severity of coronary atherosclerosis. AIM To investigate the predictive value of Gensini score on ST-segment resolution (STR) in patients undergoing primary percutaneous coronary intervention (pPCI) for acute ST-elevation myocardial infarction (STEMI). METHODS The present study prospectively included 114 consecutive patients (mean age 54 ± 10 years, 15 women) with STEMI who underwent successful pPCI. Sum of ST-segment elevation amount in millimetres was obtained before angioplasty and 60 min after pPCI. ΣSTR < 50% was accepted as a ECG sign of no-reflow phenomenon. Thrombus grading was calculated according to the results of coronary angiography, and Gensini score (GS-pPCI) was calculated after pPCI without incorporating culprit lesion. Patients were divided into two groups according to STR: those with STR(-), and those with STR(+). Patients were also analysed according to the infarct-related artery. RESULTS GS-pPCI was significantly higher in patients with STR(-) (10.1 ± 11.8 vs. 22 ± 18.6, p = 0.005). GS-pPCI was inversely correlated with STR (r = -0.287, p = 0.002). In subgroup analysis, patients in the STR(-) group with culprit lesion in left anterior descending artery and left circumflex artery also showed higher GS-pPCI (10.9 ± 13.5 vs. 23.5 ± 21.3, p = 0.03 and 9.6 ± 8.7 vs. 24.1 ± 21, p = 0.04, respectively). High thrombus burden was also observed more frequently in patients with STR(-) (68% vs. 43%, p = 0.03). Multivariate logistic regression analysis demonstrated that GS-pPCI and high thrombus burden independently predicted inadequate STR (OR 1.07, 95% CI 1.03-1.12, p = 0.001 and OR 3.28, 95% CI1.11-9.72, p = 0.03, respectively). CONCLUSIONS GS-pPCI and high thrombus burden play an important role in predicting inadequate STR in patients with STEMI treated with pPCI.


Echocardiography-a Journal of Cardiovascular Ultrasound and Allied Techniques | 2017

Easily measurable, noninvasive, and novel finding for pulmonary hypertension: Hypertrophy of the basal segment of septomarginal trabeculation of right ventricle

Gültekin Karakus; Ertuğrul Zencirci; Aleks Degirmencioglu; Tolga Guvenc; Hale Unal Aksu; Aydin Yildirim

Effect of pulmonary hypertension (PH) on right ventricular (RV) geometry constitutes an ideal target to assess both pulmonary artery pressure (PAP) and its physiological importance. In this study, we evaluated the diagnostic power of the basal segment of septomarginal trabeculation (SMT) in predicting the PH and RV hypertrophy by cardiovascular magnetic resonance (CMR) in patients with idiopathic pulmonary arterial hypertension (IPAH) and Eisenmengers syndrome (ES).

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Navin C. Nanda

University of Alabama at Birmingham

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Thouantosaporn Suwanjutah

University of Alabama at Birmingham

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