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Dive into the research topics where Emrah Oguz is active.

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Featured researches published by Emrah Oguz.


Artificial Organs | 2013

Comparison of Continuous-Flow and Pulsatile-Flow Blood Pumps on Reducing Pulmonary Artery Pressure in Patients With Fixed Pulmonary Hypertension

P. Ozturk; Ayşen Yaprak Engin; Sanem Nalbantgil; Emrah Oguz; Fatih Ayik; C. Engin; Tahir Yagdi; Sinan Erkul; O. Balcioglu; Mustafa Özbaran

Pulmonary hypertension (PH) is considered as a risk factor for morbidity and mortality in patients undergoing heart transplantation. Recently, left ventricular assist device (LVAD) implantation has been increasingly used in reducing pulmonary artery pressure (PAP) in patients with PH unresponsive to medical therapy. Herein, we aimed to compare the efficacy of continuous-flow and pulsatile-flow blood pumps on the improvement of PH in mechanical circulatory support patients. Twenty-seven patients with end-stage heart failure who underwent LVAD implantation surgery were enrolled. Fifteen of them (55.6%) had continuous-flow pump (HeartWare Ventricular Assist System, HeartWare, Inc., Miramar, FL, USA), and 12 of them (44.4%) had pulsatile pump (Berlin Heart EXCOR ventricular assist device, Berlin Heart AG, Berlin, Germany). The efficacy of LVADs on the improvement of PH was compared between continuous-flow and pulsatile pumps by the evaluation of systolic PAP, tricuspid annular plane systolic excursion (TAPSE), right ventricular systolic motion (RVSM), right ventricular ejection fraction (RVEF), and grade of tricuspid insufficiency (TI) for each of the study participants. All of the 15 patients who underwent continuous-flow blood pump implantation surgery (Group 1) were male with a mean age of 46.9 ± 11.7 years, and in pulsatile-flow blood pump implanted participants (Group 2), the mean age was 40.6 ± 16.8 years, all of whom were also male (P=0.259). Mean follow-up was 313.7 ± 241.3 days in Group 1 and 448.7 ± 120.7 days in Group 2 (P=0.139). In Group 1, mean preoperative and postoperative systolic PAP were measured as 51.7 ± 12.2 mm Hg and 22.2 ± 3.4 mm Hg, respectively, while those in Group 2 were 54.5 ± 7.5 mm Hg and 33.9 ± 6.4 mm Hg, respectively. A significantly greater decrease in systolic PAP was noticed in patients with continuous-flow blood pumps (P=0.023); however, no statistically significant difference was found when we considered the change in TAPSE between study groups (P=0.112). A statistical significance in the alteration of RVEF, RVSM, and the grade of TI during study visits was not found between the study groups (P=0.472, P=0.887, and P=0.237, respectively). Although the two studied types of LVADs were found to be effective in reducing PAP in heart transplantation candidates with PH, lesser postoperative systolic PAP values were achieved in patients who underwent continuous-flow pump implantation surgery.


Transplantation Proceedings | 2011

Ventricular Assist Device as a Bridge to Heart Transplantation in Adults

C. Engin; Fatih Ayik; Emrah Oguz; B. Eygi; Tahir Yagdi; Sultan Karakula; Mustafa Özbaran

BACKGROUND Because of the shortage of donor hearts, various ventricular asist devices (VAD) have been used in decompensated patients to prolong patient survival until a suitable heart becomes available. In this paper, we present our single-center report of adult patients in whom bridging was used with VAD. METHODS We performed a retrospective review of 14 adult patients who underwent heart transplantation after insertion of a long-term VAD. The study spans from February 2006 until September 2010. The mean patient age was 44.28 ± 11.06 years. We used the Berlin Heart EXCOR VADs (n = 11; Berlin Heart AG Berlin, Germany), or the Berlin Heart Incor (n = 2), or the Abiomed AB500 (n = 1). Preimplantation status of the subjects were critical cardiogenic shock (n = 6), deterioration on inotropes (n = 3), or stable but inotrope-dependent (n = 5). RESULTS Mean VAD support time was 153.71 days (range, 25-517). Major adverse events during VAD support included reexploration for bleeding (n = 3; 21.4%), neurologic events (n = 2; 14.3%), left VAD-related infection (n = 2; 14.3%), pneumonia (n = 1; 14.3%), or primary device failure (n = 1; 7.1%). One (7.1%) patient showed evidence of human leukocyte antigen sensitization. There were 2 deaths (14.3%) over a mean of 324 days follow-up after heart transplantation: One due to biventricular failure in the early postoperative period and the other, at 69 days from pneumonia. Rejection was observed in 2 patients who had International Society for Heart and Lung Transplantation grade 2R without hemodynamic deterioration. In our series, the 1-year mortality was 14.4% among heart transplantations without VAD implantation and 14.2% among the bridge-to-transplantation group. CONCLUSION We conclude that VAD implantation improved end-organ function before heart transplantation in critically ill patients.


Transplantation proceedings | 2011

Comparison of heart transplantation patients with ischemic and idiopathic dilated cardiomyopathy.

Hasan Güngör; Emrah Oguz; Mehmet Fatih Ayık; Serkan Ertugay; C. Engin; Tahir Yagdi; Sanem Nalbantgil; Mehdi Zoghi; Mustafa Özbaran

OBJECTIVE We retrospectively analyzed our data to compare preoperative demographic, laboratory, echocardiographic, hemodynamic findings mortality and survival rates of heart transplantation patients with ischemic (ICM) and idiopathic dilated (IDCM) cardiomyopathy. METHODS The data of 144 patients transplanted from February 1998 to January 2011 were analyzed. 38 patients with ischemic ICM and 86 patients with IDCM were compared. RESULTS Recipient age, preoperative creatinine, recipient body mass index, intraoperative cross-clamp time, donor male sex ratio, recipient male sex ratio, hyperlipidemia ratio, and previous nitrate use were significantly higher and left ventricular end systolic diameter significantly lower in patients with ICM. Major causes of death after heart transplantation were infections (31.9%), right ventricle failure (14.8%), and sudden cardiac death (14.8%). Causes of death were not different between the groups. Overall mortality in the entire population was 37.9% (47/124), and it was not different between the groups (39.5% vs 37.2%; P=.48). Early mortality (<30 days) rate was 11.2% (14/124), late mortality rate was 26.6% (33/124), and no statistically significant difference was observed between the groups. Survival analysis showed that ICM patients were not associated with worse survival compared with IDCM (71.1% vs 81.1% after 1 year, 68.1% vs 73.0% at 2 years, and 54.2% vs 62.3% at 5 years; log rank=0.57). Multivariate analysis showed that the only predictor of mortality was preoperative urea level and that heart failure etiology was not a predictor of this end point. CONCLUSIONS Patients with ICM had similar survival and mortality rate compared with IDCM.


Transplantation proceedings | 2012

New circulatory support system: heartware.

Mustafa Özbaran; Tahir Yagdi; C. Engin; Sanem Nalbantgil; Fatih Ayik; Emrah Oguz; Y. Engin; P. Ozturk

INTRODUCTION Through the new developments in medicine, heart failure therapy has advanced to mechanical circulatory support systems. The HeartWare Ventricular Assist System HVAD; HeartWare, Inc.; Miramar, Fla, USA) is a new device that is a centrifugal, intracorporeal, miniaturized and continuous flow pump that serves simple patient use and enhanced life quality. This article reports the midterm results of patients who underwent the heartware support system. MATERIALS AND METHODS We retrospectively compiled our data from December 2010, including 10 patients of mean age 51.8 years with 90% males, 70% of the overall patient cohort had dilated cardiomyopathy and remaining ones, ischemic disease. Mean left ventricular ejection fraction was 20.1% and mean systolic pulmonary artery pressure was 49.2 mm Hg. A single patient was grade 1; seven were grade 2; and remaining ones, grade 3 according to the INTERMACS (Interagency Registry for Mechanically Assisted Circulatory Support) scale. All patients were operated with cardiopulmonary bypass (CPB) with moderate hypothermia. Tricuspid ring annuloplasty was performed in 3 (30%) patients. In one patient we removed a left ventricular thrombus. In a case with severe aortic regurgitation, we placed a simple coaptation stitch at the central portion of the three aortic cusps under the aortic cross clamp. The mean CPB duration was 95.5 minutes. RESULTS There was no operative or in-hospital mortality. Mean support time was 250.67 days. During the early postoperative period, one patient experienced a minor hemorrhagic neurological event also requiring a tracheostomy due to pneumonia. This patient has completely healed and on follow-up continues a normal life. All patients were asymptomatic regarding heart failure. One patient unfortunately died because of possible pancreatic cancer and sepsis. Two patients underwent transplantations on days 159 and 172 of support. CONCLUSION The HVAD system provided effective circulatory support for patients with end-stage heart failure with low adverse event rates. Long-term results are needed particularly for destination therapy candidates.


Transplantation Proceedings | 2011

Surgical Therapy of End-Stage Heart Failure in Pediatric Patients

Fatih Ayik; Emrah Oguz; C. Engin; Tahir Yagdi; Zülal Ülger; Yüksel Atay; Mustafa Özbaran

OBJECTIVE We herein review our experience with ventricular assist device (VAD) implantation and heart transplantation in children with end-stage heart failure. METHODS We performed a retrospective nonrandomized review of all patients who underwent insertion of a Berlin Heart Excor VAD or heart transplantation in our clinic. The study spans from July 2005 to July 2010. We transplanted 11 patients of mean age 11.8 ± 4.49 years, 3 of whom with critical hemodynamic situations were bridged to heart transplantation by VAD implantation. Despite the poor right ventricular systolic functions, they did not require right rVAD. In addition, 2 patients who underwent VAD implantation are still awaiting a donor heart. The mean follow-up was 825.27 ± 630.23 days (range, 21-1,888 days). RESULTS There was no serious complication during VAD support. The overall heart transplantation mortality rate was 9.1% (1/11). In all patients, impaired end-organ functions were improved by VAD implantation before the heart transplantation. Cardiac biopsies revealed 4 grade 2R rejection episodes, which were successfully controlled in 3 patients. CONCLUSION Heart transplantation is highly effective therapy for pediatric patients with end-stage heart failure. Pediatric VAD implantation provided satisfactory safe circulatory support for small children in poor condition on the waiting list. This option should be considered for all pediatric candidates who show a poor hemodynamic status.


Transplantation Proceedings | 2011

Ege University experience in cardiac transplantation.

Mustafa Özbaran; Tahir Yagdi; C. Engin; Sanem Nalbantgil; Fatih Ayik; Emrah Oguz; Mehdi Zoghi

BACKGROUND End-stage heart failure can result from many cardiac and noncardiac entities that produce a poor prognosis. Medical and interventional modalities are widely used to treat this condition, although the ultimate therapy remains heart transplantation. Herein we present our clinical experience with 140 patients who underwent orthotopic heart transplantation. METHODS Between February 1998 and September 2010, we transplanted 140 patients with a mean age of 40 ± 13 years, including 109 men (77.8%) and 31 women (22%). There were 101 patients (73%) with dilated cardiomyopathy and 39 (27%) with ischemic cardiomyopathy. Two patients were retransplanted owing to graft failure. Sixteen patients on assist device support were successfully bridged to transplantation. RESULTS Eighteen patients (12.8%) died within 30 days with the most common causes being right ventricular failure (8/18, 44%) and infection (4/18, 22%). Overall mortality of 39% (55/140) was most commonly caused by infection (29%, 16/55) or right ventricular failure (20%, 11/55). Nine patients (16%) died suddenly outside of the hospital. Three patients died of rejection; 4 of graft failure, and 4 of malignant disease. CONCLUSIONS Heart transplantation remains the standard treatment modality for end-stage cardiac failure. But significant waiting list mortality rates are due to the worldwide shortage of donors. Heart transplantation in Turkey is feasible for a small and strictly selected number of patients with nonreversible congestive heart failure. In recent years, ventricular assist device applications have successful bridged subjects to transplantation, saving many patients on active waiting lists.


Journal of Cardiac Surgery | 2009

Effect of pleurotomy on blood loss during coronary artery bypass grafting.

Yüksel Atay; Tahir Yagdi; C. Engin; Fatih Ayik; Emrah Oguz; Alp Alayunt; Mustafa Özbaran; İsa Durmaz

Abstract  Background: We conducted a retrospective study to compare two different techniques of internal mammarian artery (IMA) preparation concerning pleurotomy upon the effects of blood loss and pulmonary functions. Methods: Between January 1998 and November 2006, 1357 consecutive patients undergoing coronary artery bypass grafting (CABG) using the left IMA, either alone or in combination with saphenous vein graft, were included in this study. The patients were divided into two groups according to the pleural opening: Group I (n = 1046) patients underwent IMA harvesting with pleurotomy and Group 2 (n = 311) patients with intact pleura. Results: During the study, 27 hospital deaths (1.9%) occurred. The amount of postoperative blood loss and blood transfusion requirements were significantly higher in Group 1 than in Group 2 (p = 0.029 and p = 0.0001). The mechanical ventilation stay was significantly higher in Group 1 than in Group 2 (p = 0.0001). The incidence of left pleural effusion and atelectasis was significantly higher in Group 1 than in Group 2 on day 1 and day 3 after operation. Conclusions: These results demonstrate that preserving pleural integrity has beneficial effects on the postoperative blood loss. Postoperative blood loss and transfusion requirements were higher in patients with pleurotomy. Left pleural effusion, atelectasis, and mechanical ventilatory stay were significantly reduced in patients with preserved pleural integrity.


Hemodialysis International | 2012

Right intra-atrial catheter placement for hemodialysis in patients with multiple venous failure

Emrah Oguz; P. Ozturk; Sinan Erkul; Tanzer Calkavur

The purpose of this study is to evaluate the efficacy and safety of direct right atrial catheter insertion for hemodialysis in patients with multiple venous access failure. We retrospectively evaluated the charts of 27 patients with multiple venous access failure who had intra‐atrial dialysis catheter placement between October 2005 and October 2010 in our clinic. Permanent right atrial dialysis catheters were placed through a right anterior mini‐thoracotomy under intratracheal general anesthesia in all patients. Demographics of the cases, the patency rates of hemodialysis via atrial catheterization, existence of any catheter thrombosis, and catheter‐related infections were documented and used in statistical analysis. Seventeen women (63%) and 10 men (37%) with the mean age of 59.0 ± 7.1 years (47–71) were enrolled in this study. Chronic renal failure was diagnosed for the mean of 78.9 ± 24.3 months (33–130). Five patients (18.5%) died. Ventricular fibrillation and myocardial infarction were the causes of death in the early postoperative period in two patients. Two of the remaining three patients died because of cerebrovascular events, and one patient died because of an unknown cause. Ten patients (37%) had been using anticoagulate agents (warfarin) because of concomitant disorders such as deep vein thrombosis, operated valve disease, and arrhythmias. Catheter thrombosis and malfunction was determined in three cases (11.1%). Intra‐atrial hemodialysis catheterization is a safe and effective life‐saving measure for the patients with multiple venous failure and without any possibility of peritoneal dialysis or renal transplantation.


Transplantation Proceedings | 2011

Ventricular Assist System Applications in End-stage Heart Failure

Tahir Yagdi; Emrah Oguz; Fatih Ayik; Serkan Ertugay; Sanem Nalbantgil; C. Engin; Mustafa Özbaran

BACKGROUND Mechanical circulatory support has an important role in the surgical therapy for heart failure. Patients deteriorating on transplantation waiting lists or those unsuitable for transplantation have been treated with ventricular assist devices. In this report, we have presented application of ventricular assist systems for patients with end-stage heart failure. METHODS Between April 2007 and September 2010, we treated 37 patients with end-stage heart failure with mechanical circulatory support, including 5 children younger than 16 years of age. Three patients were females, and the overall mean age was 40 ± 18 years (range, 1.5-67). In 29 patients we implanted paracorporeal pneumatic ventricular assist devices. Axial flow pumps were chosen to support the left ventricle in 8 patients. Biventricular support was applied in 9 patients because of their poor preoperative clinical conditions and advanced evidence of right ventricular failure. RESULTS Heart transplantation was performed in 16 patients (43%). One subject, who was managed with a left ventricular assist device implantation and coronary bypass grafting, was weaned from the system because of recovery of ventricular functions. Eleven patients (30%) are still on pump support. Nine patients (24%) died during mechanical circulatory support. The most prevalent cause of mortality was multiorgan failure (n = 5; 13.5%). Cerebrovascular hemorrhage was the cause of death in 2 patients. One patient died due to acute lung injury, and an other due to malignant melanoma. CONCLUSION Use of a ventricular assist device as a bridge-to-transplantation or as destination therapy can be performed with acceptable mortality. It may be the most promising option for patients with end-stage heart failure. Development of device technology, advanced monitoring of anticoagulation and anti-aggregation therapy, and greater clinical experience may yield better results.


Transplantation Proceedings | 2013

Left Ventricular Assist Device Implantation in Heart Failure Patients With a Left Ventricular Thrombus

C. Engin; Tahir Yagdi; O. Balcioglu; Sinan Erkul; B. Baysal; Emrah Oguz; Fatih Ayik; P. Ozturk; Mustafa Özbaran

BACKGROUND In this report, we share our experience with left ventricular assist device (LVAD) implantation in cases with a left ventricular (LV) thrombus. METHOD Over the 3 years, more than 100 end-stage heart failure cases have been treated with LVAD implantation in our center, including 6 patients with a LV thrombus. Three were detected using preoperative transthoracic echocardiography. Fifty percent of the patients had dilated cardiomyopathy and the remaining cases had an ischemic etiology. Double inotropic support with dopamine and dobutamine was used in all, with 3 drugs with the addition of adrenaline in 2 patients. In 4 cases we implanted the HeartWare Ventricular Assist System (HeartWare, Inc., Miramar, Fla, United States) and in the remaining 2 patients, the Berlin Heart EXCOR ventricular assist device (Berlin Heart AG, Berlin, Germany) for biventricular support. In 1 patient the apical ventriculotomy was extended to remove an intertrabecular thrombosis and ventricular septal surface covered with a dacron patch to minimize the thrombogenic potential. RESULTS Two patients died due to sepsis and multiorgan failure. None of the patients experienced a neurological event, pump thrombosis, or pump malfunction. Two subjects underwent re-explorations due to hemorrhage. Two candidates underwent successfull transplantation without any evidence of thrombosis in the explanted heart or device. CONCLUSION We believe that patients with a LV thrombus and preserved right ventricular function are good candidates for implantation of a LVAD after removing the intracavitary thrombus.

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