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Dive into the research topics where L. Şahiner is active.

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Featured researches published by L. Şahiner.


International Journal of Cardiology | 2011

Increased epicardial fat tissue is a marker of metabolic syndrome in adult patients

Hikmet Yorgun; Uğur Canpolat; Tuncay Hazirolan; Ahmet Hakan Ates; Hamza Sunman; M. Dural; L. Şahiner; E.B. Kaya; Kudret Aytemir; Lale Tokgozoglu; Giray Kabakci; Ali Oto

BACKGROUND Human epicardial adipose tissue (EAT) is a type of visceral adipose tissue functioning as a metabolically active endocrine organ by secreting several hormones and adipocytokines. In this study, we aimed to assess the relationship between EAT measured by dual source multidetector computed tomography (MDCT) and the presence and components of metabolic syndrome (MS). METHODS A total of 83 patients (43.4% male, mean age 56.1 ± 11.9) who underwent MDCT for suspected coronary artery disease were enrolled in this study. Thickness of the EAT was measured on contrast enhanced multiplanar reformat images with parasternal short axis view at basal, mid-ventricular and apical levels and horizontal long axis view. RESULTS The mean EAT thickness was significantly increased in patients with MS compared to those without MS (8.49 ± 1.43 mm vs 7.39 ± 2.10 mm, p<0.001). Additionally there was a graded relationship between increasing number of MS components and mean total EAT and pericoronary fat thickness (p<0.05). Simple regression analysis revealed that the presence of MS, age and body mass index (BMI) were correlated with mean EAT thickness (r=0.398, r=0.376 and r=0.371 respectively, p<0.001). Multiple regression analysis revealed that the presence of MS, age and BMI were the strongest independent variables related to EAT. CONCLUSION In this study we demonstrated that EAT and pericoronary fat thickness were associated with the presence of MS. Those findings may implicate that, EAT and pericoronary fat may be a novel and useful indicator for MS.


Journal of Cardiovascular Electrophysiology | 2013

Fragmented QRS Complex Predicts the Arrhythmic Events in Patients with Arrhythmogenic Right Ventricular Cardiomyopathy/Dysplasia

U. Canpolat; Giray Kabakci; Kudret Aytemir; M. Dural; L. Şahiner; Hikmet Yorgun; Hamza Sunman; E.B. Kaya; Lale Tokgözoğlu; Ali Oto

Fragmented QRS (frQRS) complex, with various morphology, has been recently described as a diagnostic criterion of arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D). However, there are little data regarding the prognostic role of frQRS in these patients. Therefore, we aimed to investigate the association of frQRS with arrhythmic events in patients with ARVC/D.


Europace | 2015

The role of preprocedural monocyte-to-high-density lipoprotein ratio in prediction of atrial fibrillation recurrence after cryoballoon-based catheter ablation

Uğur Canpolat; Kudret Aytemir; Hikmet Yorgun; L. Şahiner; E.B. Kaya; Serkan Cay; Serkan Topaloglu; Dursun Aras; Ali Oto

AIMS Previous studies evidenced that increased monocyte count or activity and lower high-density lipoprotein (HDL) cholesterol levels were associated with more prevalent atrial fibrillation (AF) which attributed to pro-inflammatory and pro-oxidant effects. Monocyte-to-HDL ratio (M/H ratio) is a recently emerged indicator of inflammation and oxidative stress which have been only studied in patients with chronic kidney disease. We aimed to investigate the prognostic impact of M/H ratio on AF recurrence after cryoballoon-based catheter ablation. METHODS AND RESULTS A total of 402 patients (43.5% female, age 53.5 ± 10.9 years, and 80.8% paroxysmal AF) with symptomatic AF underwent initial cryoablation procedure. Patients were categorized into quartiles on the basis of their pre-procedural M/H ratio. Post-ablation blanking period was observed for 3 months. At a mean follow-up of 20.6 ± 6.0 months, 95 patients (23.6%) had developed AF recurrence. Atrial fibrillation recurrence rates from the lowest to the highest M/H ratio quartiles were 7.4, 7.4, 16.8, and 68.4%, respectively (P < 0.001). On multivariate Cox regression analysis, the preablation M/H ratio (HR: 1.20, 95% CI: 1.15-1.25, P < 0.001), left atrial diameter, duration of AF history, and early AF recurrence were independent predictors of AF recurrence. Using a cut-off level of 11.48, the pre-ablation M/H ratio predicted AF recurrence during follow-up with a sensitivity of 85% and a specificity of 74%. CONCLUSION Elevated pre-ablation M/H ratio was associated with an increased recurrence of AF after cryoballoon-based catheter ablation. Our results support the role of pre-ablation pro-inflammatory and pro-oxidant environment in AF recurrence after ablation therapy but suggest that other factors are also important.


American Journal of Cardiology | 2013

Role of Preablation Neutrophil/Lymphocyte Ratio on Outcomes of Cryoballoon-Based Atrial Fibrillation Ablation

Uğur Canpolat; Kudret Aytemir; Hikmet Yorgun; L. Şahiner; E.B. Kaya; Giray Kabakci; Lale Tokgozoglu; Ali Oto

The neutrophil/lymphocyte ratio (NLR) has recently emerged as better indicator of inflammation and oxidative stress and has been widely studied in several cardiovascular diseases. In the present study, we evaluated the role of the preablation NLR in atrial fibrillation (AF) recurrence after cryoballoon-based catheter ablation. A total of 251 patients (47.8% women, age 54.12 ± 10.9 years, 80.1% with paroxysmal AF) with symptomatic AF underwent cryoablation. At a mean follow-up of 19.0 ± 6.6 months, 60 patients (23.9%) had developed AF recurrence. The patients who developed AF recurrence had had a greater preablation NLR (3.53 ± 0.95 vs 2.65 ± 0.23, p <0.001) and a higher white blood cell count, neutrophil count, and high-sensitivity C-reaction protein levels. On multivariate regression analysis, the preablation NLR (hazard ratio 2.15, 95% confidence interval 1.70 to 2.73, p <0.001), left atrial diameter (hazard ratio 1.09, 95% confidence interval 1.04 to 1.14, p <0.001) and early AF recurrence (hazard ratio 2.99, 95% confidence interval 1.71 to 5.23, p <0.001) were independent predictors of AF recurrence after cryoablation. Using a cutoff level of 3.15, the preablation NLR predicted AF recurrence during follow-up with a sensitivity of 84% and specificity of 75%. Patients with a preablation NLR >3.15 had a 2.5-fold increased risk of developing AF recurrence after cryoablation. In conclusion, an elevated preablation NLR was associated with increased AF recurrence after cryoballoon-based catheter ablation. Our results support the role of a preablation inflammatory environment in the development of AF recurrence after ablation therapy but suggest that other factors are also important.


Journal of Cardiovascular Electrophysiology | 2015

A Prospective DE-MRI Study Evaluating the Role of TGF-β1 in Left Atrial Fibrosis and Implications for Outcomes of Cryoballoon-Based Catheter Ablation: New Insights into Primary Fibrotic Atriocardiomyopathy

U. Canpolat; Ali Oto; Tuncay Hazirolan; Hamza Sunman; Hikmet Yorgun; L. Şahiner; E.B. Kaya; Kudret Aytemir

Transforming growth factor (TGF)‐β1 mediated atrial fibrosis plays a major role in the development of vulnerable atrial substrate for atrial fibrillation (AF). Although cryoablation effectively eliminates the triggers for AF, the impact of atrial substrate on the success of cryoablation remains unclear.


Europace | 2014

Additional benefit of cryoballoon-based atrial fibrillation ablation beyond pulmonary vein isolation: modification of ganglionated plexi

Hikmet Yorgun; Kudret Aytemir; Uğur Canpolat; L. Şahiner; E.B. Kaya; Ali Oto

AIMS It has been known that cryoballoon-based pulmonary vein isolation (PVI) is an efficacious and a safe therapeutic option to eliminate triggers of atrial fibrillation (AF). However, the effect of cryoablation on external modifiers of AF-like ganglionated plexi (GP) has never been investigated. In this study, we aimed to investigate whether vagal reactions probably due to GP modification during cryoablation, are associated with success rates during follow-up. METHODS AND RESULTS A total of 145 patients (age: 54.5 ± 10.1, 52.4% males and 80.7% paroxysmal AF) who were symptomatic despite treatment with ≥ 1 antiarrhythmic drug underwent PVI with cryoballoon. Occurrences of intraprocedural vagal reactions were recorded in all patients. Intraprocedural vagal reaction was observed in 59 patients (40.7%). Vagal reaction characterized by bradycardia and hypotension was more common in patients free of AF recurrence as was the requirement of atropine administration or temporary pacing (46.2 vs. 15.4%, P = 0.004 and 38.7 vs. 7.7%, P = 0.002, respectively). At a median 17 (4-27) months follow-up, AF recurrence was observed in 26 (17.9%) patients. Multivariate Cox regression analysis showed that non-paroxysmal AF, left atrial diameter, and early recurrence significantly increased AF recurrence; however, requirement of atropine administration or temporary pacing (hazard ratio: 0.064; 95% confidence interval: 0.008-0.48, P = 0.008) decreased AF recurrence. CONCLUSION Our findings indicate that vagal reactions during cryoablation, as a surrogate marker of cardiac ANS modification, decrease AF recurrence in a subgroup of patients with paroxysmal and persistent AF. This finding may be attributed to the concomitant ablation of GP during antral PVI.


International Journal of Cardiology | 2013

A proposal for a new scoring system in the prediction of catheter ablation outcomes: Promising results from the Turkish Cryoablation Registry

Uğur Canpolat; Kudret Aytemir; Hikmet Yorgun; L. Şahiner; E.B. Kaya; Ali Oto

BACKGROUND Although cryoballoon based catheter ablation is an effective therapeutic option in atrial fibrillation (AF), a significant amount of patients failed to remain in sinus rhythm at long term follow-up. Appropriate selection of patients for catheter ablation reduces unnecessary interventions and prevents complications related with catheter ablation. The purpose of our study is to propose a new scoring system in the prediction of recurrence after AF ablation with cryoballoon. METHOD A total of 236 patients (54% male, age 54.6 ± 10.45 years and 79.6% paroxysmal) with symptomatic AF underwent an index cryoablation. The first 3 months after AF ablation is defined as blanking period. Predictors of AF recurrence after cryoablation were analyzed with multivariate Cox regression analysis. BASE-AF2 score [acronym stands for Body mass index >28 kg/m(2) (1); Atrial dilatation >40 mm (1); current Smoking (1); Early recurrence (1); duration of AF history >6 years (1) and non-paroxysmal type (1) of AF] is identified by the total number of significant predictors of recurrence in each patient (range=0-6). RESULTS At median 20 (range: 12-30) months follow-up, 74.5% of the patients were free from AF recurrence. Of these patients, 64 (27.1%) patients had a BASE-AF2 score of ≥3. Patients with AF recurrence had a higher mean BASE-AF2 score (3.27±0.82 vs. 1.1 ± 0.95, p<0.001) compared to patients without AF recurrence. ROC analysis showed that a BASE-AF2 score of ≥3 well predicted AF recurrence with a sensitivity of 80.8% and a specificity of 91.6% (AUC=0.94; 95% CI: 0.89-0.97, p<0.001). A BASE-AF2 score of ≥3 was found to be an independent predictor of AF recurrence (HR: 3.34, 95% CI: 2.34-4.76, p=0.001). CONCLUSION BASE-AF2, which was identified as a new scoring system, has well predicted AF recurrence and could be helpful in selecting appropriate patients for interventional strategy.


International Journal of Cardiology | 2013

The cardiovascular effects of premature ovarian failure

Hikmet Yorgun; Lale Tokgozoglu; Uğur Canpolat; Kadri Murat Gurses; Gurkan Bozdag; Zuhal Yapıcı; L. Şahiner; E.B. Kaya; Giray Kabakci; Ali Oto; Murat Tuncer; Kudret Aytemir

BACKGROUND Previous studies have shown that cardiovascular risk is increased in premature ovarian failure (POF). To determine the effects of POF on different parameters of cardiovascular health, we investigated the relationship between POF and circulating endothelial progenitor cells (EPC), endothelial function, carotid intima media thickness (CIMT) and left ventricular diastolic function. METHODS We compared 23 female POF patients (mean age; 37.8 ± 10.8 years) with 20 gender and age-matched healthy controls. Circulating CD133(+)/34(+) and CD34(+)/KDR(+) EPCs were determined by using flow-cytometry. Ultrasound assessment of endothelial function by brachial artery flow-mediated dilatation (FMD) and CIMT was made. Left ventricular systolic and diastolic function was assessed by standard 2D and M-mode echocardiography and tissue Doppler velocities. RESULTS Brachial artery FMD was significantly impaired in patients with POF compared with CG (6.3 ± 1.9% vs 10.4 ± 3.7%, p<0.05). Furthermore, circulating EPCs were lower among patients with POF compared to controls for CD133(+)/34(+) and CD34(+)/KDR(+) cells (p<0.05). There was a significant correlation between serum estradiol levels and EPC number (CD 133+/34+) (r=0.329, p<0.05). POF patients had increased CIMT compared to controls (0.67 ± 0.17 vs 0.43 ± 0.10, p<0.05). When diastolic functions were assessed, patients with POF had lower Epeak, Apeak and mitral CP and higher DT and IVRT (p<0.05, respectively). CONCLUSION Our findings indicate that endothelial function as well as circulating EPCs, CIMT and diastolic function are significantly affected in young women with POF which may have an adverse long-term effect on cardiovascular prognosis.


Cardiology Journal | 2013

Predictors of atrial fibrillation recurrence after atrial fibrillation ablation with cryoballoon.

Banu Evranos; Kudret Aytemir; Ali Oto; Sercan Okutucu; U.N. Karakulak; L. Şahiner; B. Kaya; Giray Kabakci

BACKGROUND Catheter ablation of atrial fibrillation is recommended for patients with symptomatic paroxysmal atrial fibrillation (PAF) despite anti-arrhythmic drugs (AADs). Radiofrequency ablation is widely accepted as an effective treatment for PAF. Cryoenergy by cryoballoon technique is an alternative to radiofrequency (RF) ablation. Cryoballoon ablation is safe, and has a similar success rate in comparison to RF ablation. AF recurrence with cryoballoon ablation is roughly 30%. The aim of this study is to determine the predictors of AF recurrence after cryoballoon ablation. METHODS AND RESULTS Sixty one patients with symptomatic PAF despite AADs without structural heart disease were included. Cryoballoon ablation was performed in 60 patients (36 males, mean age: 54.6 ± 10.7, mean left atrium size: 3.74 ± 0.39 mm). Transthoracic echocardiography including tissue Doppler imaging was performed in all subjects during sinus rhythm at baseline and after the ablation. Intra-atrial and inter-atrial electromechanical delays, and PA-lateral were measured. All patients were scheduled for 24 h Holter recording at baseline and at 3, 6, 9 months follow-up. Venous samples were collected to measure CK-MB, Troponin-T (TnT), erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) levels at baseline and 24 h after ablation. Median follow up was 10 (8-12) months. Forty eight (80%) patients were in sinus rhythm during the follow up. In receiver operating curve (ROC) analysis, intraleft atrial electromechanical delay and PA-lateral achieve an area under the curve (AUC) 0.97 (p < 0.001) and 0.69 (p < 0.001) for the ability to predict AF recurrence. A cut-off value for baseline intra left atrial electromechanical delay of 29.5 ms predicted AF recurrence with sensitivity of 85% and specifity of 98%. A cut-off value for PA-lateral of 125 ms predicted AF recurrence with sensitivity of 80% and specifity of 90%. In ROC analysis, age achieves an AUC 0.822 (p = 0.006) for the ability to predict AF recurrence. A cut-off value for age of 64 predicted AF recurrence with sensitivity of 71% and specifity of 90%. Early recurrence of AF (HR = 60, 95% CI 18.61-417.86, p < 0.001) predicted also late recurrence of AF. CONCLUSIONS The increase in AF recurrence by increased intraleft atrial electromechanical delay, PA-lateral and older age show the importance of substrate in AF mechanism. Early recurrence was the strongest predictor of late recurrence of AF; therefore, existence of blanking period for cryoballoon ablation should be questioned.


Autonomic Neuroscience: Basic and Clinical | 2012

Evaluation of various cardiac autonomic indices in patients with familial Mediterranean fever on colchicine treatment

Uğur Canpolat; Muhammed Dural; Kudret Aytemir; Ali Akdogan; E.B. Kaya; L. Şahiner; U. Yalçın; Asena Gökçay Canpolat; Meral Calguneri; Giray Kabakci; Lale Tokgozoglu; Ali Oto

BACKGROUND Familial Mediterranean fever (FMF) is characterized by sporadic, acute attacks of fever and serositis. Cardiovascular involvement is one of the leading cause of morbidity and mortality among FMF patients. Herein, we aimed to evaluate cardiac autonomic functions in FMF patients without overt cardiac symptoms. METHODS We enrolled 38 patients (20 female; mean age 34.4 ± 10.2 years) with FMF and 34 healthy subjects (18 female; mean age 33.2 ± 9.3 years). All participants underwent 24-hour Holter recording. Heart rate recovery (HRR) indices were calculated by subtracting first, second, and third minute heart rates from maximal heart rate. All patients underwent heart rate variability (HRV), heart rate turbulance (HRT) and QT dispersion analysis. The mean FMF duration was 9.8 ± 4.2 years. RESULTS Both groups were similar with regard to baseline characteristics. Mean HRR1 (p=0.001), HRR2 (p=0.003) and HRR3 (p<0.001) were significantly lower in FMF group. SDNN (standard deviation of all NN intervals), SDANN (SD of the 5 min mean RR intervals), RMSSD (root square of successive differences in RR interval), and PNN50 (proportion of differences in successive NN intervals >50 ms) and high-frequency (HF) components were significantly decreased, but low frequency (LF) and LF/HF were significantly higher in FMF patients. HRT onset and slope were significantly less negative in FMF patients. Also, QTd was significantly higher in FMF patients (p<0.001). CONCLUSION Patients with FMF showed delayed recovery of heart rate and abnormal HRV and HRT parameters with respect to normal subjects. Cardiac autonomic functions might be involved in FMF patients even in patients without cardiac symptoms.

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Ali Oto

Hacettepe University

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M. Dural

Hacettepe University

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B. Kaya

Hacettepe University

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