Mehmet Ali Oto
Hacettepe University
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Publication
Featured researches published by Mehmet Ali Oto.
Europace | 2015
Kudret Aytemir; Kadri Murat Gurses; Muhammed Ulvi Yalcin; Duygu Kocyigit; M. Dural; Banu Evranos; Hikmet Yorgun; Ahmet Hakan Ates; Mehmet Levent Sahiner; E.B. Kaya; Mehmet Ali Oto
AIMS The second-generation cryoballoon (Arctic Front Advance™) (Arc-Adv-CB) has a redesigned injection system which distributes the refrigerant homogenously to the frontal balloon surface. The aim of this study was to compare the efficacy and safety of the Arc-Adv-CB and its predecessor (Arctic Front™) (Arc-CB) in patients who underwent pulmonary vein isolation (PVI) for atrial fibrillation (AF). METHODS AND RESULTS Three hundred and six patients (55.35 ± 10.60 years, 47.05% male) were included in the study. A total of 1205 pulmonary veins were attempted for PVI with either Arc-CB or Arc-Adv-CB. The follow-up durations were 30 (23-38) and 10 (8-13) months in Arc-CB and Arc-Adv-CB groups, respectively (P < 0.001). When the blanking period was considered, freedom from AF after a single ablation procedure was 68.53 and 90.83% in patients undergoing PVI with Arc-CB and Arc-Adv-CB, respectively. The most frequent complication was transient phrenic nerve palsy (PNP) which occurred in five(2.54%) and nine(8.26%) of patients undergoing PVI with Arc-CB and Arc-Adv-CB, respectively (P = 0.040). Left atrial (LA) diameter (hazard ratio, HR: 3.552, 95% CI: 2.034-6.201, P < 0.001), smoking history (HR:1.643, 95% CI: 1.011-2.671, P = 0.045), persistent AF (HR:1.725, 95% CI: 1.021-2.915, P = 0.041), duration of AF (HR:1.039, 95% CI: 1.000-1.080, P = 0.047), and early AF recurrence (HR:2.399, 95% CI: 1.443-3.989, P < 0.001) were associated with increased late AF recurrence. On the other hand, intraprocedural vagal reactions (HR: 0.550, 95% CI: 0.331-0.915, P = 0.021) and Arc-Adv-CB use (HR: 0.441, 95% CI: 0.225-0.866, P = 0.017) were associated with lower late AF recurrence. Left atrial diameter (HR: 3.072, 95% CI: 1.646-5.732, P < 0.001), early AF recurrence (HR: 1.906, 95% CI: 1.103-3.291, P = 0.021), and Arc-Adv-CB use (HR: 0.472, 95% CI: 0.239-0.931, P = 0.030) were independent predictors for late AF recurrence. CONCLUSION Our study has shown that Arc-Adv-CB use is associated with lower late AF recurrences at the cost of an increased risk for PNP.
Pacing and Clinical Electrophysiology | 1991
Mehmet Ali Oto; Haldun Muderrisoglu; Mehmet Bülent Özin; Mehmet Emin Korkmaz; Aydin Karamehmetoglu; Aysel Oram; Erdem Oram; Sevket Ugurlu
Eleven patients with rate responsive pacemakers (7 men, 4 women, mean age 41 years with a range of 23‐60) were randomly assigned to a cross‐over study in order to assess their overall exercise capacity and quality‐of‐life (QOL) scores. All of the pacemakers were implanted for complete AV block or sick sinus syndrome. The pacemakers were randomly programmed into VVI or rate responsive (VVIR) pacing modes for 3‐week study periods in each mode. At the end of each period, an exercise test was performed and the QOL was evaluated by the “Hacettepe Quality‐of‐Life Questionnaire”. All patients exercised longer in the VVIR mode (mean 10.54 ± 0,73 min) than in the VVI mode (mean 7.81 ± 0.62 min) (P < 0.05). QOL scores were also found to be significantly higher in the VVIR mode (mean 173.81 ± 16.22 points) compared to the VVI mode (mean 156.27 ± 21.22 points) (P < 0.01). In conclusion, our results suggest that VVIR pacing offers a better QOL in addition to an improved exercise capacity, compared to the single chamber nonrate modulated pacing (VVI).
Journal of Cardiovascular Computed Tomography | 2015
Duygu Kocyigit; Kadri Murat Gurses; Muhammed Ulvi Yalcin; Gamze Turk; Banu Evranos; Hikmet Yorgun; Mehmet Levent Sahiner; E.B. Kaya; Tuncay Hazirolan; Lale Tokgozoglu; Mehmet Ali Oto; Necla Ozer; Kudret Aytemir
BACKGROUND Epicardial adipose tissue (EAT) is a metabolically active fat depot. Studies have investigated the effect of EAT thickness on outcomes of radiofrequency catheter ablation of atrial fibrillation (AF). However, data on the relationship between EAT thickness and outcome of cryoballoon-based pulmonary vein isolation (PVI) are lacking. OBJECTIVE In this study, we investigate the association between EAT thickness and AF recurrence after cryoballoon-based PVI. METHODS Patients with symptomatic paroxysmal or persistent AF despite ≥1 antiarrhythmic drug(s) were scheduled for cryoballoon-based PVI for AF per the recent recommendations. Periatrial, periventricular, and total EAT thickness measurements were obtained from preprocedural multidetector CT scans. RESULTS A total of 249 patients (55.6 ± 10.7 years; 48.2% male; 18.5% persistent AF) were involved in the study. Patients were followed-up for 29 months (8-48 months). When blanking period was considered, freedom from AF after the ablation procedure was 75.9% at a median follow-up of 29 months. Total periatrial EAT thickness (18.1 ± 6.2 vs. 14.7 ± 4.7 mm; P < .001) was greater in patients with late AF recurrence when compared to those without. On the other hand, periventricular or total EAT thickness measurements did not differ between both groups (P > .05). Multivariate Cox proportional hazard regression analysis showed that periatrial EAT thickness (hazard ratio, 1.086; P = .001) and left atrial volume index (hazard ratio, 1.144; P < .001) were independent predictors for late AF recurrence. CONCLUSION Quantification of EAT thickness from preprocedural multidetector CT scans may serve as a beneficial parameter for prediction of AF recurrence after cryoballoon-based PVI.
Europace | 2015
Kadri Murat Gurses; Muhammed Ulvi Yalcin; Duygu Kocyigit; Sacit Altug Kesikli; Uğur Canpolat; Hikmet Yorgun; Mehmet Levent Sahiner; E.B. Kaya; Tuncay Hazirolan; Necla Ozer; Mehmet Ali Oto; Dicle Guc; Kudret Aytemir
AIMS Atrial fibrosis has been found to be associated with recurrent atrial fibrillation (AF) following catheter ablation. Autoantibodies against M2-muscarinic receptors (anti-M2-R) may play a role in the development of AF by inducing left atrial (LA) fibrosis. In this study, we aim to compare anti-M2-R levels between paroxysmal lone AF patients and healthy control subjects and to investigate the relationship between pre-ablation anti-M2-R level, LA fibrosis quantified by delayed enhancement magnetic resonance imaging (DE-MRI), and AF recurrence following cryoablation. METHODS AND RESULTS Thirty-one patients with paroxysmal lone AF (53.4 ± 8.0 years, 61% male), who underwent cryoballoon-based ablation, along with 31 healthy control subjects were included. Enzyme-linked immunosorbent assay tests to measure serum anti-M2-R levels were performed in both groups and DE-MRI was done to quantify LA fibrosis prior to the ablation in the patients. Anti-M2-R levels were higher in the study population when compared with control subjects [212.4 (103.2-655.5) vs. 73.0 (39.5-299.1) ng/mL, P < 0.001]. Anti-M2-R level predicted moderate-extensive LA fibrosis independent of other measures [odds ratio: 1.26 (95% confidence interval (CI): 1.04-1.53), P = 0.017]. At a mean follow-up of 35.2 ± 3.5 months, nine patients (29.0%) had AF recurrence. In the Cox regression model including pre-ablation anti-M2-R level, LA diameter, LA volume index, and moderate-extensive LA fibrosis, only moderate-extensive LA fibrosis predicted late AF recurrence independent of other measures [hazard ratio: 29.41 (95% CI: 3.52-250.00), P = 0.002]. CONCLUSION Serum anti-M2-R levels may be associated with the severity of LA fibrosis and may be implicated in the pathophysiology of AF recurrence following cryoablation. Detection of anti-M2-R levels may help select appropriate patients for the procedure.
European Journal of Heart Failure | 2003
Mehmet Alikasifoglu; Lale Tokgozoglu; Tayfun Acil; Enver Atalar; Mehmet Ali Oto; Süleyman Sirri Kes; Ergul Tuncbilek
Tumor necrosis factora (TNF-a) is a proinflammatory cytokine with pleiotropic biological effects. Numerous studies have indicated a role of TNFa in the pathophysiology of congestive heart failure w1–4x. Since genetic polymorphisms in the TNF locus were known to be related to several autoimmune, infectious, and neoplastic diseases w5x, the association between TNFa gene polymorphism and dilated cardiomyopathy (DCM) was also studiedw6–8x. However, the results obtained were contradictory. Studies done in patients with different ethnic origins yielded contrasting results w6,7x.
American Journal of Cardiology | 2016
Kadri Murat Gurses; Duygu Kocyigit; Muhammed Ulvi Yalcin; Hande Canpinar; Hikmet Yorgun; Mehmet Levent Sahiner; E.B. Kaya; Mehmet Ali Oto; Necla Ozer; Dicle Guc; Kudret Aytemir
Atrial fibrillation (AF) is the most common sustained arrhythmia. Inflammation has been suggested to play a vital role in the pathogenesis. Previous studies have investigated expression of inflammatory markers in AF. Several studies have focused on the effects of toll-like receptors (TLRs) on heart in terms of capability of modulating inflammation. In this study, we aimed to investigate whether peripheral monocyte TLR expression was associated with the AF presence, and recurrence of AF after cryoablation, as a reflection of inflammatory status. Patients with AF who were scheduled for cryoballoon-based ablation for AF and age- and gender-matched subjects in sinus rhythm were included. Peripheral monocyte TLR-2 and TLR-4 expressions were evaluated by flow cytometric analysis in peripheral venous blood samples obtained during evaluation in outpatient clinics: 172 patients (56.5 ± 6.6 years, 52.3% men) were included in the study. Peripheral monocyte TLR-2 and TLR-4 expression levels were significantly higher in patients with AF (p <0.05). Among patients with AF, 12 patients (14.0%) developed AF recurrence at a follow- up of 17 months. Multivariate Cox regression analysis showed that left atrial volume index (hazard ratio 2.040, 95% CI 1.197 to 3.477, p = 0.009) and monocyte TLR-4 expression (hazard ratio 1.226, 95% CI 1.042 to 1.443, p = 0.014) were independent predictors of AF recurrence after blanking period following second-generation cryoballoon-based pulmonary vein isolation for paroxysmal AF. In conclusion, our study highlights the role of TLR-mediated inflammation in the pathogenesis of AF. This link may also constitute a therapeutic target in patients with AF.
Journal of Cardiovascular Electrophysiology | 2015
Muhammed Ulvi Yalcin; Kadri Murat Gurses; Duygu Kocyigit; Sacit Altug Kesikli; M. Dural; Banu Evranos; Hikmet Yorgun; L. Sahiner; E.B. Kaya; Mehmet Ali Oto; Dicle Guc; Kudret Aytemir; Necla Ozer
Recent evidence has suggested that autoantibodies may play an important role in the development of atrial fibrillation (AF). The predictive value of preprocedural autoantibodies against beta‐1 adrenergic receptor (anti‐β1‐R) and M2‐muscarinic acetylcholine receptor (anti‐M2‐R) for AF recurrence following cryoballoon‐based pulmonary vein isolation (PVI) is still unclear. We aimed to determine the predictive value of preprocedural anti‐β1‐R and anti‐M2‐R levels for AF recurrence.
American Journal of Cardiovascular Drugs | 2018
Begum Yetis Sayin; Mehmet Ali Oto
Cardiologists are seeing an increasing number of oncology patients every day, and acute coronary syndrome (ACS) is one of the problems patients encounter during follow-up. Cardio-oncology is the care of patients with cancer and cardiovascular disease, whether overt or occult, already established or acquired during treatment. Cardiovascular complications can occur acutely during or shortly after treatment and persist as long-term effects for months to years after treatment. As a delayed effect of cancer treatment, cardiovascular damage can occur months to years after the initial treatment. Vasospasm, thrombosis, and radiation-induced cardiovascular diseases can all cause ACS. Careful surveillance of ACS symptoms and regular screening during follow-up of patients with malignancy are suggested. In this review, we summarize the ACS we usually encounter during a range of cancer treatments or post cancer survival by providing illustrative case examples.
American Journal of Cardiology | 2014
Muhammed Ulvi Yalcin; Kadri Murat Gurses; Duygu Kocyigit; Hikmet Yorgun; Mehmet Levent Sahiner; E.B. Kaya; Kudret Aytemir; Mehmet Ali Oto
A B S T R A C T S any major complication. During a median follow-up of 18 months, 32 patients (78.1%) remained free of AF recurrence. Patients with AF recurrence showed higher pre-ablation plasma Pcoll-1-C levels than patients without AF recurrence (108.5 ng/mL vs 65.0 ng/mL, p1⁄40.001). Multivariate Cox regression analysis pointed out that the Pcoll-1-C level (p1⁄40.001) and early AF recurrence (p1⁄40.011) were the independent predictors of AF recurrence in late follow-up. Conclusion: Our findings suggest that the Pcoll-1-C level before PVI could be a crucial predictor of AF recurrence after cryoballoon based PVI.
American Journal of Cardiology | 2015
Kadri Murat Gurses; Muhammed Ulvi Yalcin; Duygu Kocyigit; Hande Canpinar; Banu Evranos; Hikmet Yorgun; Mehmet Levent Sahiner; E.B. Kaya; Necla Ozer; Lale Tokgozoglu; Mehmet Ali Oto; Dicle Guc; Kudret Aytemir