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Publication
Featured researches published by C. Orhan.
Perfusion | 2018
Philippe Grieshaber; Tobias Schneider; Lukas Oster; C. Orhan; Peter Roth; Bernd Niemann; Andreas Böning
Introduction: Prophylactic intra-aortic balloon counterpulsation (pIABC) is recommended for high-risk patients undergoing coronary artery bypass grafting (CABG) surgery. Criteria for high-risk patients benefiting from pIABC are unclear. This study aimed to specifically describe the effect of pIABC on outcomes of patients with acute myocardial infarction (AMI) undergoing CABG. Methods: In 178 of 484 AMI patients (non-ST-segment elevation myocardial infarction [NSTEMI] or ST-segment elevation myocardial infarction [STEMI] ≤5 days before surgery) without cardiogenic shock who underwent CABG between 2008 and 2013, pIABC was initiated preoperatively. After propensity score matching, the outcomes of 400 patients were analyzed (pIABC: 150; Control: 250). Results: After propensity score matching, baseline and operative characteristics were balanced between the groups except for a higher rate of patients with a left ventricular ejection fraction (LVEF)≤30% in the pIABC group (26% vs. Control: 13%; p=0.032). Seven point two percent (7.2%) of the control patients received an IABP intraoperatively or postoperatively. Postoperative extracorporeal life support (ECLS) was only needed in the control group (1.2% vs. 0%; p=0.01). Postoperative plasma curves of troponin I, creatine kinase (CK) and creatine kinase isoform MB (CK-MB) levels were reduced in the pIABC group compared with the control group. In-hospital mortality was reduced in the pIABC group (3.3% vs. control: 6.4%; p=0.18). After multivariate adjustment for other preoperative risk factors, pIABC was significantly protective concerning in-hospital mortality (HR 0.56; 95%-CI 0.023-0.74; p=0.021). Mortality (pIABC vs. control) was more affected in patients with preoperative LVEF≤30% (2/36 (5.6%) vs. 6/31 (19%); heart rate (HR) 0.25; 95%-CI 0.046-1.3; p=0.13) compared with LVEF>30% (3/114 (2.6%) vs. 10/219 (4.6%); HR 0.56; 95%-CI 0.15-2.1; p=0.55). Long-term survival did not differ between the groups. Conclusions: pIABC in CABG for AMI is associated with reduced perioperative cardiac injury and in-hospital mortality. Long-term survival is not affected.
Journal of the American College of Cardiology | 2016
Philippe Grieshaber; Nadine Nink; Dursun Guenduez; Peter Roth; C. Orhan; Meshal Elzien; Bernd Niemann; Andreas Böning; Ahmed Koshty
We aimed to develop an operative method for safe and reliable deployment of endovascular stent prostheses in the ascending aorta for high-risk patients with acute type A aortic dissection who are deemed inoperable using conventional surgery. We developed a combined transapical and transfemoral
Thoracic and Cardiovascular Surgeon | 2012
Raed Aser; C. Orhan; B. Niemann; Peter Roth; Andre Perepelitsa; Tim Attmann; Andreas Böning
OBJECTIVE To determine the pacing and sensing properties of different temporary epicardial pacemaker electrodes after cardiac surgery depending on position at the heart and time after surgery. METHODS From September 2009 to October 2010, 60 patients undergoing cardiac surgery were prospectively randomized into two groups: group O: Osypka-electrodes (n = 30), group M: Medtronic-electrodes (n = 30). In position 1, the bipolar electrodes were inserted onto the anterior wall of the right ventricle and at the right atrial auricle, in position 2, onto the diaphragmal wall of the right ventricle and at the aortic aspect of the superior vena cava medial close to the atrium. Sensing values and pacing thresholds were measured for all electrodes during surgery, on day 1 and every second day up to day 10 after surgery. RESULTS In both groups, pacing thresholds (both positions) were higher during surgery (ventricle 3.1 ± 0.6 V, atrium 3.1 ± 0.3 V) than at day 1 (ventricle 2.4 ± 0.7 V, atrium 2.4 ± 0.3 V) and increased during the perioperative course until day 10 (ventricle 4.7 ± 1.0 V, atrium 4.9 ± 1.1 V, p = 0.04, p = 0.02). P and R wave amplitudes did not change over time (atrium 5.1 ± 0.1 mV initially, 4.2 ± 0.1 mV at removal (p = ns); ventricle 10.4 ± 0.2 mV vs. 10.1 ± 0.25 mV). Group M had better median pacing thresholds compared with group O (atrium: 2.9 ± 0.6 V vs. 3.9 ± 0.7 V, p = 0.04 and ventricle: 2.6 ± 0.6 V vs. 3.9 ± 0.6 V, p = 0.045). Atrial position 1 was superior to position 2 concerning pacing thresholds of Medtronic electrodes (2.1 ± 0.3 mV vs. 3.4 ± 0.4 mV, p = 0.02). Osypka-electrodes were easier to handle due to their more pliable texture. CONCLUSIONS 1. Up to postoperative day 10, adequate pacing and sensing performance was achieved by both electrode types in each position. 2. Medtronic electrodes had better pacing thresholds in atrium and ventricle after day 5. 3. Positioning of pacemaker electrodes does not alter functionality. 4. Handling of Osypka electrodes was easier than that of Medtronic electrodes.
Thoracic and Cardiovascular Surgeon | 2018
Philippe Grieshaber; T. Schneider; L. Oster; C. Orhan; Peter Roth; B. Niemann; A. Böning
Journal of Cardiothoracic Surgery | 2018
Philippe Grieshaber; Lukas Oster; Tobias Schneider; Victoria Johnson; C. Orhan; Peter Roth; Bernd Niemann; Andreas Böning
Thoracic and Cardiovascular Surgeon | 2016
Philippe Grieshaber; L. Oster; T. Schneider; Peter Roth; C. Orhan; B. Niemann; A. Böning
Thoracic and Cardiovascular Surgeon | 2016
Philippe Grieshaber; T. Schneider; L. Oster; I. Oswald; C. Orhan; Peter Roth; B. Niemann; A. Böning
Thoracic and Cardiovascular Surgeon | 2015
B. Niemann; M. Micoogullari; I. Schweizer; H.L. Wißbrock; E. Dominik; C. Orhan; Peter Roth; A. Böning; Susanne Rohrbach
Thoracic and Cardiovascular Surgeon | 2015
B. Niemann; E. Dominik; Susanne Rohrbach; C. Orhan; Peter Roth; Philippe Grieshaber; M. Djufri; A. Böning
Thoracic and Cardiovascular Surgeon | 2014
B. Niemann; E. Dominik; Susanne Rohrbach; Peter Roth; C. Orhan; L. Li; A. Böning