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Dive into the research topics where R. Tandler is active.

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Featured researches published by R. Tandler.


Journal of Heart and Lung Transplantation | 2008

Influence of Inflow Cannula Length in Axial-flow Pumps on Neurologic Adverse Event Rate: Results From a Multi-center Analysis

Christof Schmid; Michael J. Jurmann; Dietrich E. Birnbaum; Tiziano Colombo; Volkmar Falk; Giuseppe Feltrin; Andrea Garatti; Michele Genoni; Gino Gerosa; Peter Göttel; Jan Gummert; Robert Halfmann; Dieter Hammel; Ewald Hennig; Friedrich Kaufmann; Marco Lanfranconi; Bart Meyns; Friedrich W. Mohr; Johannes Müller; Dimitar Nikolov; Kestutis Rucinskas; Hans H. Scheld; Franz X. Schmid; Michael Schneider; Vytautas Sirvydis; R. Tandler; Ettore Vitali; Dirk Vlasselaers; Michael Weyand; Markus J. Wilhelm

BACKGROUND The application of axial-flow pumps in patients with end-stage heart failure reveals a significantly reduced infectious complication rate as compared with rates observed with pulsatile devices. The remaining adverse event rate relates mainly to thromboembolic complications with neurologic consequences. We investigated the dependence of the neurologic adverse event rate on the length of the inflow cannula. METHODS A total of 216 consecutive patients with an axial-flow pump (INCOR; Berlin Heart GmbH, Berlin, Germany) were included in a retrospective multi-center analysis. In 138 patients, a short inflow cannula (24-mm tip length into the left ventricle), and in 78 patients a long inflow cannula (tip length 34 mm) was applied. RESULTS Patients with a long inflow cannula (LC) demonstrated a better survival rate than those with a short inflow cannula (SC) at the end of the observation period (LC, 63.4%; SC, 52.9%; p = 0.05). The thromboembolic adverse event rate was also significantly lower. Only 3 of the 78 patients (3.8%) with an LC had a thromboembolic adverse event (thromboembolic events per patient-year = 0.11) as compared with 32 (23.2%) of SC patients (thromboembolic events per patient-year = 0.50, p < 0.001). CONCLUSIONS Patients with a long inflow cannula had a better survival rate and a lower incidence of cerebrovascular adverse events than patients with a short inflow cannula.


American Journal of Cardiology | 2009

Comparison of Dual Source Computed Tomography Versus Intravascular Ultrasound for Evaluation of Coronary Arteries at Least One Year After Cardiac Transplantation

Tiziano Schepis; Stephan Achenbach; M. Weyand; Philip Raum; Mohamed Marwan; Tobias Pflederer; Werner G. Daniel; R. Tandler; Markus Kondruweit; Dieter Ropers

This study evaluated the ability of dual-source computed tomography (DSCT) to detect coronary allograft vasculopathy (CAV) in heart transplant recipients using intravascular ultrasound (IVUS) as the standard of reference. Thirty patients with heart transplants (81% men, mean age 40 years) underwent DSCT (330-ms gantry rotation, 2 x 64 x 0.6-mm collimation, 60- to 80-ml contrast agent, no additional beta blockers) before invasive coronary angiography including IVUS of 1 vessel. Detection of CAV by DSCT was qualitatively defined as the presence of any coronary plaque. Mean heart rate during dual-source computed tomographic scanning was 80 +/- 14 beats/min. Four hundred fifty-nine segments with a vessel caliber >or=1.5 mm according to quantitative coronary angiography were evaluated in 30 patients. Of these, 96% were considered to have excellent or good image quality. IVUS detected CAV in 17 of 30 patients (57%) and in 41 of 110 coronary segments (37%). Compared to IVUS, sensitivity, specificity, positive and negative predictive values for the detection of CAV by DSCT were 85%, 84%, 76%, and 91%, respectively. In conclusion, DSCT permits the investigation of transplant recipients concerning the presence of CAV with good image quality and high diagnostic accuracy.


Journal of Clinical Microbiology | 2007

Fatal Bioprosthetic Aortic Valve Endocarditis Due to Cardiobacterium valvarum

Walter Geissdörfer; R. Tandler; Christian Schlundt; Michael Weyand; Werner G. Daniel; Christoph Schoerner

ABSTRACT Cardiobacterium valvarum was isolated from the blood of a 71-year-old man with fatal aortic valve endocarditis. The API NH system was used for phenotypic characterization of the C. valvarum strain. This is the first case of infective endocarditis caused by C. valvarum in Germany and the first case worldwide affecting a prosthetic valve and lacking an obvious dental focus.


Asaio Journal | 2000

Long-term anticoagulation with recombinant hirudin in a patient on left ventricular assist device support

R. Tandler; Michael Weyand; Christof Schmid; Gradaus R; Schmidt C; Hans H. Scheld

We report on a 24 year old man with a Novacor left ventricular assist device (LVAD) who underwent long-term treatment with intravenous recombinant hirudin due to a heparin induced thrombocytopenia (HIT II) after suffering from an ischemic stroke.


Journal of Cardiac Surgery | 1994

Aortic Valve Replacement with Cryopreserved PuImonary Allograft

Wolfgang Konertz; R. Tandler; Michael Hasfeld; Anke Fahrenkamp; Guenther Breithardt; Hans H. Schled

Experimental as well as clinical data support the finding of using the pulmonary valve as a systemic semilunar valve. From January 1990 to December 1992, 89 patients received pulmonary cryopreserved allografts as aortic valve replacement. Sixteen subjects suffering from native or prosthetic valve endocarditis were included. Age ranged from 10 to 74 years. Sixty‐five patients received isolated aortic valve replacement and 24 patients required additional surgical measures, such as coronary artery bypass graft, mitral valve reconstruction, replacement of the ascending aorta, supravalvular patch aortoplasty, ventricular septal defect closure, or myectomy. All operations were performed with normothermic bypass and cold cardioplegic arrest. Follow‐up is maintained by visits to the outpatient clinic and echocardiographic assessment of the valve status every 3 months during the first year and every 6 months thereafter. There were four early and three late deaths. Four valves had to be removed: one intraoperatively and three 2, 4, and 24 months postoperatively. Echocardiographic assessment proved that gradients across the valve were low or absent. The majority of patients showed trivial or no aortic regurgitation during follow‐up. No thromboem‐bolic events have been observed and no new endocarditis occurred. Thus, event‐free survival at 3 years is 87%. The results with pulmonary allografts have shown to be comparable to aortic allografts. Even in patients with acute native or prosthetic valve endocarditis, the use of cryopreserved pulmonary allografts has shown no adverse effects. We continue to implant cryopreserved pulmonary allografts In the aortic position. The long‐term function of the valve, however, must be established, making continued evaluation of postoperative patients mandatory. (J Card Surg 1994;9:43–49)


Interactive Cardiovascular and Thoracic Surgery | 2016

Reduction of INCOR® driveline infection rate with silicone at the driveline exit site.

Daniele Camboni; Matthaeus Zerdzitzki; Stephan Hirt; R. Tandler; Michael Weyand; Christof Schmid

Objectives A silicone interface at skin level of left ventricular assist device (LVAD) may reduce the risk of driveline (DL) exit site infections when compared with other materials (e.g. velour). The purpose of this study was to evaluate the rate of DL exit site infection according to the presence of silicone or velour at the exit site with the redesigned INCOR, facilitating the positioning of silicone at the exit site. Methods The rate of DL exit site infection and overall survival were compared between the two groups (silicone group, n = 16/velour group, n = 24) with 1-year follow-up postimplantation. Results Risk factors for infection were more prevalent in the silicone group (obesity P = 0.33, prevalence of renal dysfunction P = 0.007, higher CRP levels P = 0.001). During the observation period, 6 patients developed a DL infection (25%) in the velour group, whereas 1 patient developed a DL infection in (6%) in the silicone group (P = 0.19). The event-per-patient year (EPPY) rates were 0.34 and 0.10 for velour group and silicone group, respectively (P = 0.30). All DL infections could be treated successfully by the antibiotic treatment, surgical debridement and ultimately high urgency heart transplantation, resulting in no direct DL infection-related mortality in this cohort. One-year survival was similar in both the groups (silicone 69 vs 75% in the velour group; P = 0.67). Conclusions Fewer infections were observed at the exit site in case of a silicone-covered DL, without reaching statistical significance. More patients and longer observation periods are needed to demonstrate a statistical difference.


Thoracic and Cardiovascular Surgeon | 2012

Single centre experience with prolonged waiting time on transplant list with "high-urgency" status.

C. Heim; Ehab Nooh; Markus Kondruweit; M. Weyand; R. Tandler

INTRODUCTION The waiting list for heart transplantation (HTx) in Eurotransplant area has grown to a record size of nearly 1,300 patients, whereas only around 600 hearts were transplanted last year. The prolonged time for patients awaiting HTx on the high-urgency (HU) status leads mostly to serious medical complications. OBJECTIVE The aim of this study was to study the trend of changes in the frequency of ventricular assist device (VAD) implantation in patients on the HU status. METHODS A total of 22 adult patients awaiting transplantation on the HU status at our hospital between January 2011 and December 2011 were analyzed, assessing risk profile, blood group, and complication rates in terms of VAD implantation or death. Results were compared with 16 consecutive patients who were on transplant list with the HU status between January 2010 and December 2010 at our institution. RESULTS Mean age was 49.5 ± 12.1 (2010 group) years and 51.4 ± 10.7 years (2011 group; p = 0.62). Mean logEuroSCORES raised not significantly from 9.1 ± 6.3% (2010 group) to 10.7 ± 14.7% (2011 group; p = 0.68). Six patients died on the HU status and seven patients had to be supplied with a VAD in 2011. In comparison with the preceding year, only two patients died in 2010 and none of our patients on the HU status had to be provided with mechanical circulatory support. CONCLUSION Because of the prolonged waiting time on the HU list, the earlier-mentioned data demonstrate a negative trend in transplant medicine. Especially when taking into consideration that five of seven patients who needed a VAD implantation during the HU waiting period had blood group O. Furthermore, the data derived from Eurotransplant show that the waiting period for patients with blood group O was considerably longer when compared with patients of the same average body height and weight but with other blood groups.


The Journal of Thoracic and Cardiovascular Surgery | 2008

Stenting of the superior vena cava in a patient with a total artificial heart

Markus Kondruweit; Thomas Strecker; Timo Seitz; Michael Uder; Michael Weyand; R. Tandler

F or patients with decompensated biventricular heart failure refractory to medical management, the total artificial heart (TAH) is a sufficient therapy option. One possible postoperative problem is the compression of the superior vena cava (SVC) caused by bleeding that will lead to tamponade with low output of the TAH. In a 55-year-old man, such a TAH was implanted as a bridge to transplantation without any perioperative complications. However, 7 months after the patient was discharged home, he was readmitted with signs of congestion of the upper body and low flow of the TAH because of SVC compression caused by pericardial effusion. In an interventional procedure a stent was implanted in the SVC, which led to full recovery of the patient and normal flow patterns of the TAH.


Journal of Cardiothoracic and Vascular Anesthesia | 2018

Accuracy and Trending Ability of the Fourth-Generation FloTrac/EV1000 System in Patients With Severe Aortic Valve Stenosis Before and After Surgical Valve Replacement

Andreas Eisenried; Raphael Klarwein; H. Ihmsen; Andreas Wehrfritz; R. Tandler; C. Heim; J. Fechner

OBJECTIVE Evaluate the accuracy and trending ability of the fourth-generation FloTrac/EV1000 (Edwards Lifesciences, Irvine, CA) system in patients with severe aortic valve stenosis by comparing FloTrac/EV1000-derived cardiac output (CCO-FT) with continuous thermodilution pulmonary artery catheter (CCO-PAC) measurements before and after surgical valve replacement. DESIGN Prospective clinical study. SETTING Anesthesia for cardiac surgery, operating room, single-center university hospital. PARTICIPANTS Twenty-five patients were included. After exclusion, 20 patients undergoing elective aortic valve replacement were analyzed. INTERVENTIONS After induction of general anesthesia, CCO-FT and CCO-PAC values were recorded every 30 seconds before and after aortic valve replacement with a bioprosthesis under cardiopulmonary bypass (CPB). MEASUREMENTS AND MAIN RESULTS Data were analyzed separately from skin incision to last suture and before and after CPB. Regression analyses, Bland-Altman analyses, and trending analyses (4-quadrant plot, polar plot) were performed. The percentage errors of the FloTrac/EV1000 were 69.7% and 59.3% before and after CPB, respectively. The concordance rates (CRs) and angular CRs of the FloTrac/EV1000 were 50.9% and 57.1%, and 48.7% and 61.9% before and after CPB, respectively. CONCLUSION This study revealed a low level of agreement and poor trending ability of the FloTrac/EV1000 system compared to continuous thermodilution pulmonary artery catheter in patients with severe aortic stenosis. Although there was a slight improvement after surgical valve replacement and CPB, the results were not within acceptable limits to replace CCO-PAC in this patient population.


Journal of Cardiothoracic Surgery | 2015

Routine surveillance endomyocardial biopsy for the detection of cellular rejection beyond 2 years after cardiac transplantation.

C. Heim; Fatos Ballazhi; Thorsten Zielezinski; Markus Kondruweit; Michael Weyand; R. Tandler

Endomyocardial biopsy (EMB) is widely used for routine surveillance of cardiac allograft rejection. The need for continued EMB beyond the first year after cardiac transplantation is controversial.

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Markus Kondruweit

University of Erlangen-Nuremberg

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M. Weyand

University of Erlangen-Nuremberg

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C. Heim

University of Erlangen-Nuremberg

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Richard Feyrer

University of Erlangen-Nuremberg

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