Jan Gummert

Herz- und Diabeteszentrum Nordrhein-Westfalen, Bad Oeyhausen, North Rhine-Westphalia, Germany

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Publications (474)1591.34 Total impact

  • Europace 10/2015; DOI:10.1093/europace/euv313 · 3.67 Impact Factor
  • Andreas Koster · Jan F Gummert · Uwe Schirmer · Armin Zittermann ·

    European journal of cardio-thoracic surgery: official journal of the European Association for Cardio-thoracic Surgery 10/2015; DOI:10.1093/ejcts/ezv346 · 3.30 Impact Factor
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    ABSTRACT: Management of chronic rejection is challenging since there are not sufficient preventive or therapeutic strategies. The rejection process leads to overexpression of ED-A(+) fibronectin (ED-A(+) Fn). The human antibody F8, specific to ED-A(+) Fn, may serve as a vehicle for targeted delivery of bioactive payloads, e.g. interleukin 10 (IL-10). The aim of this study was to investigate the therapeutic effects of the fusion protein F8-interleukin-10 (F8-IL10) in the process of chronic rejection development. A heterotopic rat heart transplantation model was used to induce chronic rejection. For therapeutic interventions, the immunocytokines F8-humanIL10 (DEKAVIL), F8-ratIL10 as well as KSF-humanIL10 (irrelevant antigen-specificity) were used. Treatment was performed weekly for 10weeks starting at day 7 after transplantation (1mg/animal). In the cardiac allografts, treatment with F8-huIL10 or F8-ratIL10 was associated with increased heart weights, a higher grade of chronic rejection, increased CIF, higher protein expression levels of alpha-smooth muscle actin (α-SMA), an augmented infiltration with inflammatory cells (CD4+, CD8+ and CD68+ cells) and higher serum levels of brain natriuretic peptide (BNP) compared to the control groups. All observed treatment effects are transplantation-specific since the F8 antibody is specific to ED-A(+) Fn that is not expressed in healthy hearts. A clear targeting effect of F8-huIL10 as well as F8-ratIL10 could be proven. Against that background, a further study is needed to address the question, if F8-IL10 treatment is capable to reduce CAV and CIF starting at a time point when chronic rejection has fully developed (therapeutic approach). Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
    International Journal of Cardiology 09/2015; 195. DOI:10.1016/j.ijcard.2015.05.144 · 4.04 Impact Factor
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    ABSTRACT: Objectives: In end-stage heart failure patients with left-ventricular assist device implantation and tricuspid valve (TV) regurgitation grade >2, the surgical strategy for TV regurgitation is unclear at present. We aimed to compare clinical outcomes in patients receiving left-ventricular assist device (LVAD) implants with or without TV repair (TVR). Methods: We included 58 patients with TV regurgitation grade >2 in our data analysis. Thirty-two patients received TVR during LVAD implantation (TVR+ group), whereas 26 patients did not receive TVR (TVR- group). We assessed demographic and various preoperative clinical and echocardiographic parameters in both groups. The primary end-point was survival up to 1 year. Secondary end-points were the incidence of prolonged mechanical ventilatory support, rethoracotomy, early and late right heart failure and liver or kidney failure. Results: Preoperatively, the two groups differed according to heart failure diagnosis, need for inotropic support and haemodynamic/echocardiographic parameters such as transpulmonary gradient, cardiac index and the ratio of the right-ventricular end-diastolic diameter to the left-ventricular end-diastolic diameter. The survival rate up to 1 year was 53.1% in the TVR+ group and 73.1% in the TVR- group (P = 0.176). The propensity score (PS)-adjusted 1-year mortality risk with the TVR- group as a reference was 3.05 for the TVR+ group (95% confidence interval: 0.84-11.11; P = 0.091). Secondary end-points did not differ significantly between study groups. Conclusions: Data indicate that end-stage heart failure patients with TV regurgitation grade >2 undergoing LVAD implants do not benefit from concomitant TVR. Results have to be confirmed by prospective studies.
    Interactive Cardiovascular and Thoracic Surgery 09/2015; 21(6). DOI:10.1093/icvts/ivv260 · 1.16 Impact Factor
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    ABSTRACT: An 81-year-old man with high-grade aortic valve stenosis and status post-coronary artery bypass grafting and supracoronary replacement of the ascending aorta was referred for transcatheter aortic valve implantation. He was in New York Heart Association class III and had dyspnea. After appropriate screening, we implanted a 29-mm SAPIEN XT valve (Edwards Lifesciences, Irvine, CA USA) through a transapical approach because of severe peripheral arterial occlusive disease. Postinterventional aortography revealed correct positioning and function of the valve and free coronary ostia but contrast extravasation in the vicinity of the interposed vascular prosthesis, resulting in severe luminal narrowing. We chose to manage the stenosis with an endovascular stent. After stenting, extravascular compression was markedly reduced, and the pressure gradient disappeared. The patient was discharged home on the 20th postoperative day. Three months later, computed tomography depicted correct positioning of both grafts. The patient's general health is good, and he is now in New York Heart Association class II. This case illustrates a complication of transcatheter aortic valve implantation specific for patients with an ascending aortic graft. Although stenting may be a good solution, as depicted by this case, self-expanding transcatheter aortic valves should be preferred in patients with ascending aortic grafts to avoid the described complication.
    Innovations Technology and Techniques in Cardiothoracic and Vascular Surgery 09/2015; 10(4). DOI:10.1097/IMI.0000000000000173
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    Clinical Research in Cardiology 08/2015; 104(11). DOI:10.1007/s00392-015-0903-7 · 4.56 Impact Factor
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    ABSTRACT: Introduction: Cardiotoxicity is a fatal complication of chemotherapeutic agents in which the implantation of a mechanical circulatory support system (MCS) can be a life-saving modality. The aim of this article is to analyse this available therapeutic option for patients with cardiotoxicity induced by treatment of malignancy in the light of current literature. We analysed our recent experience with MCS implantations in patients who have advanced heart failure associated with chemotherapy-induced cardiotoxicity. Methods In the hospital registries of 386 adult cardiomyopathy patients who were supported with a long-term impantable MCS in our institution between January 2008 and June 2012, were retrospectively evaluated. In 11 of these patients (mean age ?SD years; overall %; female/male (n); 42 +/- 14, 2.8%, 4/7) MCS was implemented due to chemotherapeutic drug-induced cardiomyopathy (CDIC). Pre-operative and post-operative data of CDIC patients were analysed. Results: In this cohort of CDIC patients, mean duration of circulatory support was 413 ?445 days. One of the patients was successfully bridged to heart transplantation (HTx) after exclusion of possible contraindications. In one patient, left ventricular assist device (LVAD) was successfully explanted after myocardial recovery. In the late post-operative period, five patients expired due to multi-organ failure and gastrointestinal haemorrhage. The remaining 4 patients are still under follow-up on LVAD-support. One of these patients was listed for high-urgency HTx because of device-related infection. Conclusion: Cardiotoxicity leading to advanced heart failure is a serious complication of chemotherapeutic agents with a high risk of mortality. In our series LVAD therapy seems to be a beneficial and safe option. LVAD therapy is an acceptable option in chemotherapy-induced, advanced cardiomyopathy.
    Acta cardiologica 08/2015; 70(4):430-434. DOI:10.2143/AC.70.4.3094652 · 0.65 Impact Factor
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    Kardiologie up2date 07/2015; 11(02):109-125. DOI:10.1055/s-0034-1392452
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    Zeitschrift für Herz- Thorax- und Gefäßchirurgie 07/2015; 29(4):241-253. DOI:10.1007/s00398-015-0018-5
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    ABSTRACT: In cardiac surgery, the association between red blood cell (RBC) transfusion and clinical outcome is elusive. We investigated in a large cohort of patients who underwent isolated coronary artery bypass grafting (CABG) the effect of transfusion of 1-2 units of leucocyte-depleted RBCs on mortality and multiorgan failure. The investigation included all patients from July 2009 to June 2014 who underwent CABG at our institution and received no (n = 1478) or 1-2 units of RBCs (n = 1528). The primary end-point was 30-day mortality; secondary end-points were major organ dysfunction. A subgroup analysis assessed the effect of the duration of RBC storage on patient outcome. Statistical analysis was performed using propensity score (PS) adjustment. The 30-day mortality rate was 0.3% in the RBC- group and 0.2% in the RBC+ group. Compared with the RBC- group, PS-adjusted odds ratio (OR) of 30-day mortality in the RBC+ group was 0.29 [95% confidence interval (CI): 0.06-1.50; P = 0.14]. PS-adjusted OR of a 'prolonged intensive care unit (ICU) stay' (>48 h) was significantly higher in the RBC+ group than in the RBC- group [OR 1.49 (95% CI: 1.14-1.95); P = 0.004], but major clinical complications such as low cardiac output syndrome, stroke, haemofiltration, wound infection and prolonged mechanical ventilator support (>24 h) did not differ significantly between groups. Duration of blood storage was not independently associated with clinical outcome. Our data do not indicate a transfusion-related increase in mortality and multiorgan failure in patients undergoing isolated CABG. © The Author 2015. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.
    European journal of cardio-thoracic surgery: official journal of the European Association for Cardio-thoracic Surgery 07/2015; DOI:10.1093/ejcts/ezv252 · 3.30 Impact Factor
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    ABSTRACT: Background Heart transplantation (HTx) is still considered the therapeutic gold standard in end-stage heart failure. Methods In "high urgent" (HU)-listed patients for HTx (n = 274) and patients receiving left ventricular assist device (LVAD) implants (n = 332), we compared 1-year overall survival (primary endpoint) and 1-year probability of HTx and therapy failure (the need for LVAD implantation in HU-listed patients or the need for HU listing in LVAD patients) (secondary endpoints). Results In the HU and LVAD group, 1-year survival was 86.8 and 64.7%, respectively (p < 0.001). The propensity score (PS)-adjusted hazard ratio of mortality did not differ between the groups and for the LVAD group (reference = HU group) was = 1.36 (95% confidence interval [CI]: 0.85-2.19; p = 0.198). The PS-adjusted hazard ratio for the failure to receive HTx for the LVAD group (reference = HU group) was = 9.77 (95% CI: 6.00-15.89; p < 0.001). The corresponding hazard ratio for therapy failure for the LVAD group was = 0.16, 95% CI: 0.10-0.27; p < 0.001). Conclusion Despite considerable differences in the probability of HTx and therapy failure, 1-year overall survival was similar in HU and LVAD patients. Georg Thieme Verlag KG Stuttgart · New York.
    The Thoracic and Cardiovascular Surgeon 07/2015; DOI:10.1055/s-0035-1556816 · 0.98 Impact Factor
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    ABSTRACT: Because of its low rate of clinical complications, miniaturized extracorporeal perfusion systems (MEPS) are frequently used in heart centers worldwide. However, many recent studies refer to the higher probability of gaseous microemboli formation by MEPS, caused by subzero pressure values. This is the main reason why various de-airing devices were developed for today's perfusion systems. In the present study, we investigated the potential benefits of a simple one-way-valve connected to a volume replacement reservoir (OVR) for volume and pressure compensation. In an experimental study on 26 pigs, we compared MEPS (n = 13) with MEPS plus OVR (n = 13). Except OVR, perfusion equipment was identical in both groups. Primary endpoints were pressure values in the venous line and the right atrium as well as the number and volume of air bubbles. Secondary endpoints were biochemical parameters of systemic inflammatory response, ischemia, hemodilution and hemolysis. One animal was lost in the MEPS + OVR group. In the MEPS + OVR group no pressure values below -150 mmHg in the venous line and no values under -100 mmHg in right atrium were noticed. On the contrary, nearly 20 % of venous pressure values in the MEPS group were below -150 and approximately 10 % of right atrial pressure values were below -100 mmHg. Compared with the MEPS group, the bubble counter device showed lower numbers of arterial air bubbles in the MEPS + OVR group (mean ± SD: 13444 ± 5709 vs. 1 ± 2, respectively; p < 0.001). In addition, bubble volume was significantly lower in the MEPS + OVR group than in the MEPS group (mean ± SD: 1522 ± 654 μl vs. 4 ± 6 μl, respectively; p < 0.001). The proinflammatory cytokine interleukin-6 and biochemical indices of cardiac ischemia (creatine kinase, and troponin I) were comparable between both groups. The use of a miniaturized perfusion system with a volume replacement reservoir is able to counteract excessive negative venous line pressures and to reduce the number and volume of arterial air bubbles. This approach may lead to a lower rate of neurological complications.
    BMC Anesthesiology 05/2015; 15(1):81. DOI:10.1186/s12871-015-0058-0 · 1.38 Impact Factor
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    ABSTRACT: Based on a voluntary registry of the German Society for Thoracic and Cardiovascular Surgery (GSTCVS), data of all heart surgery procedures performed in 78 German cardiac surgical units during the year 2014 are presented. In 2014, a total of 100,398 cardiac surgical procedures (implantable cardioverter-defibrillator and pacemaker procedures excluded) were submitted to the registry. More than 14.2% of the patients were older than 80 years, describing an increase of 0.4% compared with the previous year. The unadjusted in-hospital mortality for 40,006 isolated coronary artery bypass grafting procedures (84.7% on-pump, 15.3% off-pump) was 2.6%. In 31,359 isolated valve procedures (including 9,194 catheter-based procedures), an in-hospital mortality of 4.4% was observed. This annual updated registry of the GSTCVS is published since 1989. It is an important tool for quality assurance and voluntary public reporting by illustrating current standards and actual developments for nearly all cardiac surgical procedures in Germany.
    The Thoracic and Cardiovascular Surgeon 05/2015; 63(4):258-69. DOI:10.1055/s-0035-1551676 · 0.98 Impact Factor
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    ABSTRACT: Background Left ventricular assist device (LVAD) implants bear the risk of driveline/device infections and technical failures. Methods We assessed clinical outcome in LVAD patients with device-related complications. Group 1 (n = 12) received device exchange (DEx) as destination therapy (DT), group 2 (n = 15) received DEx as a bridge to transplant (BTT), group 3 (n = 34) was allocated to receive high-urgency (HU) heart transplantation (HTx), and group 4 (n = 27) had device-related complications that could only be solved by HTx. Primary endpoint was 1-year overall survival. Results Age and Simplified Acute Physiology Score II differed significantly between groups and were highest in group 1, lowest in group 3. One-year survival in groups 1 to 4 was 66.7, 60.0, 82.4, and 70.4% (p = 0.30). Covariate-adjusted odds ratio of 1-year survival (reference: group 1) was for group 2 = 1.52 (95% confidence interval [CI]: 0.42-5.57), for group 3 = 1.13 (95% CI: 0.28-4.56), and for group 4 = 1.89 (95% CI: 0.51-7.04; p for trend 0.70). Clinical complications (need of mechanical ventilator support, extracorporeal circulatory membrane oxygenation (ECMO) implants, kidney/liver dialysis) were comparable between groups. Conclusion Data indicate similar 1-year clinical outcomes in LVAD patients with device-related complications receiving DEx or HTx. Georg Thieme Verlag KG Stuttgart · New York.
    The Thoracic and Cardiovascular Surgeon 05/2015; DOI:10.1055/s-0035-1549356 · 0.98 Impact Factor

  • The Journal of Heart and Lung Transplantation 04/2015; 34(4). DOI:10.1016/j.healun.2015.01.016 · 6.65 Impact Factor

  • The Journal of Heart and Lung Transplantation 04/2015; 34(4). DOI:10.1016/j.healun.2015.01.015 · 6.65 Impact Factor
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    ABSTRACT: Background: Preoperative anemia is considered an independent risk factor of poor clinical outcome in cardiac surgical patients. Low vitamin D status may increase anemia risk. Methods: We investigated 3,615 consecutive patients scheduled for cardiac surgery to determine the association between preoperative anemia (hemoglobin [Hb] <12.5 g/dL) and circulating levels of the vitamin D metabolites 25-hydroxyvitamin D (25OHD) and 1,25-dihydroxyvitamin D (1,25[OH]2D). Results: Of the study cohort, 27.8 % met the criteria for anemia. In patients with deficient 25OHD levels (<30 nmol/l) mean Hb concentrations were 0.5 g/dL lower than in patients with adequate 25OHD levels (50.0-125 nmol/l; P<0.001). Regarding 1,25(OH)2D, mean Hb concentrations were 1.2 g/dL lower in the lowest 1,25(OH)2D category (<40 pmol/l) than in the highest 1,25(OH)2D category (>70 pmol/l; P<0.001). In multivariable-adjusted logistic regression analyses, the odds ratios for anemia of the lowest categories of 25OHD and 1,25(OH)2D were 1.48 (95%CI:1.19-1.83) and 2.35 (95%CI:1.86-2.97), compared with patients who had adequate 25OHD levels and 1,25(OH)2D values in the highest category, respectively. Anemia risk was greatest in patients with dual deficiency of 25OHD and 1,25(OH)2D (multivariable-adjusted OR = 3.60 (95%CI:2.40-5.40). Prevalence of deficient 25OHD levels was highest in anemia of nutrient deficiency, whereas low 1,25(OH)2D levels were most frequent in anemia of chronic kidney disease. Conclusion: This cross-sectional study demonstrates an independent inverse association between vitamin D status and anemia risk. If confirmed in clinical trials, preoperative administration of vitamin D or activated vitamin D (in case of chronic kidney disease) would be a promising strategy to prevent anemia in patients scheduled for cardiac surgery.
    PLoS ONE 04/2015; 10(4):e0124751. DOI:10.1371/journal.pone.0124751 · 3.23 Impact Factor
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    ABSTRACT: The European Registry for Patients with Mechanical Circulatory Support (EUROMACS) was founded on 10 December 2009 with the initiative of Roland Hetzer (Deutsches Herzzentrum Berlin, Berlin, Germany) and Jan Gummert (Herz- und Diabeteszentrum Nordrhein-Westfalen, Bad Oeynhausen, Germany) with 15 other founding international members. It aims to promote scientific research to improve care of end-stage heart failure patients with ventricular assist device or a total artificial heart as long-term mechanical circulatory support. Likewise, the organization aims to provide and maintain a registry of device implantation data and long-term follow-up of patients with mechanical circulatory support. Hence, EUROMACS affiliated itself with Dendrite Clinical Systems Ltd to offer its members a software tool that allows input and analysis of patient clinical data on a daily basis. EUROMACS facilitates further scientific studies by offering research groups access to any available data wherein patients and centres are anonymized. Furthermore, EUROMACS aims to stimulate cooperation with clinical and research institutions and with peer associations involved to further its aims. EUROMACS is the only European-based Registry for Patients with Mechanical Circulatory Support with rapid increase in institutional and individual membership. Because of the expeditious data input, the European Association for Cardiothoracic Surgeons saw the need to optimize the data availability and the significance of the registry to improve care of patients with mechanical circulatory support and its potential contribution to scientific intents; hence, the beginning of their alliance in 2012. This first annual report is designed to provide an overview of EUROMACS' structure, its activities, a first data collection and an insight to its scientific contributions.
    European journal of cardio-thoracic surgery: official journal of the European Association for Cardio-thoracic Surgery 04/2015; 47(5):770-6; discussion 776-7. DOI:10.1093/ejcts/ezv096 · 3.30 Impact Factor
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    ABSTRACT: Right ventricular failure (RVF) is a major cause of morbidity and mortality in left ventricular assist device (LVAD) recipients. To identify preoperative echocardiographic predictors of post-LVAD RVF. Data were collected for 42 patients undergoing LVAD implantation in Germany. RVF was defined as the need for placement of a temporary right ventricular assist device or the use of inotropic agents for 14 days. Data for RVF patients were compared with those for patients without RVF. A score (ARVADE) was established with independent predictors of RVF by rounding the exponentiated regression model coefficients to the nearest 0.5. RVF occurred in 24 of 42 LVAD patients. Univariate analysis identified the following measurements as RVF risk factors: basal right ventricular end-diastolic diameter (RVEDD), minimal inferior vena cava diameter, pulsed Doppler transmitral E wave (Em), Em/tissue Doppler lateral systolic velocity (SLAT) ratio and Em/tissue Doppler septal systolic velocity (SSEPT) ratio. Em/SLAT≥18.5 (relative risk [RR] 2.78, 95% confidence interval [CI] 1.38-5.60; P=0.001), RVEDD≥50mm (RR 1.97, 95% CI 1.21-3.20; P=0.008) and INTERMACS (Interagency Registry for Mechanically Assisted Circulatory Support) level 1 (RR 1.74, 95% CI 1.04-2.91; P=0.04) were independent predictors of RVF. An ARVADE score>3 predicted the occurrence of post-implantation RVF with a sensitivity of 89% and a specificity of 74%. The ARVADE score, combining one clinical variable and three echocardiographic measurements, is potentially useful for selecting patients for the implantation of an assist device. Copyright © 2015 Elsevier Masson SAS. All rights reserved.
    Archives of cardiovascular diseases 04/2015; 108(5). DOI:10.1016/j.acvd.2015.01.011 · 1.84 Impact Factor
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    ABSTRACT: The number of implanted biological valves for treatment of valvular heart disease is growing and a percentage of these patients will eventually undergo a transcatheter valve-in-valve (ViV) procedure. Some of these patients will represent challenging cases. The aim of this study was to develop a feasible algorithm to plan and in vitro simulate a new interventional procedure to improve patient outcome. In addition to standard diagnostic routine, our algorithm includes 3D printing of the annulus, hydrodynamic measurements and high-speed analysis of leaflet kinematics after simulation of the procedure in different prosthesis positions as well as X-ray imaging of the most suitable valve position to create a 'blueprint' for the patient procedure. This algorithm was developed for a patient with a degenerated Perceval aortic sutureless prosthesis requiring a ViV procedure. Different ViV procedures were assessed in the algorithm and based on these results the best option for the patient was chosen. The actual procedure went exactly as planned with help of this algorithm. Here we have developed a new technically feasible algorithm simulating important aspects of a novel interventional procedure prior to the actual procedure. This algorithm can be applied to virtually all patients requiring a novel interventional procedure to help identify risks and find optimal parameters for prosthesis selection and placement in order to maximize safety for the patient. © The Author 2015. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.
    Interactive Cardiovascular and Thoracic Surgery 04/2015; 21(1). DOI:10.1093/icvts/ivv080 · 1.16 Impact Factor

Publication Stats

7k Citations
1,591.34 Total Impact Points


  • 2009-2015
    • Herz- und Diabeteszentrum Nordrhein-Westfalen
      • • Heart Center North Rhine-Westphalia
      • • Klinik für Thorax- und Kardiovaskularchirurgie
      Bad Oeyhausen, North Rhine-Westphalia, Germany
    • Ruhr-Universität Bochum
      • Institut für Klinische Chemie, Transfusions- und Laboratoriumsmedizin
      Bochum, North Rhine-Westphalia, Germany
  • 2009-2014
    • Krankenhaus Bad Oeynhausen
      Bad Oeyhausen, North Rhine-Westphalia, Germany
  • 1995-2013
    • Georg-August-Universität Göttingen
      Göttingen, Lower Saxony, Germany
    • Universitätsmedizin Göttingen
      • Department of Thoracic and Cardiovascular Surgery
      Göttingen, Lower Saxony, Germany
  • 2007-2009
    • Universitätsklinikum Jena
      • Klinik für Herz- und Thoraxchirurgie
      Jena, Thuringia, Germany
    • Universität Ulm
      Ulm, Baden-Württemberg, Germany
    • Friedrich Schiller University Jena
      • Clinic of Cardiac and Thoracic Surgery
      Jena, Thuringia, Germany
    • Jackson Memorial Hospital
      Miami, Florida, United States
  • 1996-2009
    • University of Leipzig
      • • Lehrstuhles für Herzchirurgie
      • • Klinik und Poliklinik für Kinderchirurgie
      Leipzig, Saxony, Germany
  • 2008
    • Isar Heart Center
      Münchenbernsdorf, Thuringia, Germany
    • Isala Klinieken
      • Department of Cardiology
      Zwolle, Overijssel, Netherlands
  • 2004
    • University of Occupational and Environmental Health
      • School of Medicine
      Kitakyūshū, Fukuoka, Japan
  • 2001-2002
    • Kunststoff-Zentrum in Leipzig
      Leipzig, Saxony, Germany
  • 1998-2002
    • Stanford University
      • Department of Cardiothoracic Surgery
      Stanford, California, United States
  • 1999-2001
    • Stanford Medicine
      • Department of Cardiothoracic Surgery
      Stanford, California, United States