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Dive into the research topics where Mark Greer is active.

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Featured researches published by Mark Greer.


European Respiratory Journal | 2012

The prognostic impact of follow-up assessments in patients with idiopathic pulmonary arterial hypertension

Nils Nickel; Heiko Golpon; Mark Greer; Lars Knudsen; Karen M. Olsson; V. Westerkamp; Tobias Welte; Marius M. Hoeper

Current guidelines for the treatment of patients with idiopathic pulmonary arterial hypertension (IPAH) recommend basing therapeutic decision-making on haemodynamic, functional and biochemical variables. Most of these parameters have been evaluated as risk predictors at the time of diagnosis. The aim of the present study was to assess the prognostic impact of changes in these parameters after initiation of targeted therapy. A cohort of 109 patients with IPAH who had undergone haemodynamic, functional and biochemical assessments at baseline and 3–12 months after initiation of pulmonary arterial hypertension (PAH)-targeted therapy, were followed for a median 38 months in order to determine predictors of mortality at baseline and during the course of their disease. Within the observation period, 53 (48.6%) patients died and four (3.7%) underwent lung transplantation. Kaplan–Meier estimates for transplantation-free survival were 92%, 67%, and 51% at 1, 3, and 5 yrs, respectively. Among baseline variables, 6-min walk distance, right atrial pressure, cardiac index, mixed-venous oxygen saturation (Sv,O2) and N-terminal-pro brain natriuretic peptide (NT-proBNP) were independent predictors of survival. During follow-up, changes in World Health Organization functional class, cardiac index, Sv,O2 and NT-proBNP proved significant predictors of outcome. When assigned to prognostic groups, improvements as well as deteriorations in these parameters after initiation of PAH-targeted therapy had a strong impact on survival. Measurements obtained at follow-up had a higher predictive value than variables obtained at baseline. Changes in established predictors of outcome during the course of the disease provide important prognostic information in patients with IPAH.


American Journal of Transplantation | 2013

Phenotyping established chronic lung allograft dysfunction predicts extracorporeal photopheresis response in lung transplant patients.

Mark Greer; Martin Dierich; C. de Wall; Hendrik Suhling; J. Rademacher; Tobias Welte; Axel Haverich; G. Warnecke; P. Ivanyi; S. Buchholz; Jens Gottlieb; Thomas Fuehner

Chronic lung allograft dysfunction (CLAD) remains the leading cause of mortality in lung transplant recipients after the first year. Treatment remains limited and unpredictable. Existing data suggests extracorporeal photopheresis (ECP) may be beneficial. This study aimed to identify factors predicting treatment response and the prognostic implications. A single center retrospective analysis of all patients commencing ECP for CLAD between November 1, 2007 and September 1, 2011 was performed. In total 65 patients were included, 64 of whom had deteriorated under azithromycin. Median follow‐up after commencing ECP was 503 days. Upon commencing ECP, all patients were classified using proposed criteria for emerging clinical phenotypes, including “restrictive allograft syndrome (RAS)”, “neutrophilic CLAD (nCLAD)” and “rapid decliners”. At follow‐up, 8 patients demonstrated ≥10% improvement in FEV1, 27 patients had stabilized and 30 patients exhibited ≥10% decline in FEV1. Patients fulfilling criteria for “rapid decliners” (n = 21, p = 0.005), RAS (n = 22, p = 0.002) and those not exhibiting neutrophilia in bronchoalveolar lavage (n = 44, p = 0.01) exhibited poorer outcomes. ECP appears an effective second line treatment in CLAD patients progressing under azithromycin. ECP responders demonstrated improved progression‐free survival (median 401 vs. 133 days). Proposed CLAD phenotypes require refinement, but appear to predict the likelihood of ECP response.


Intensive Care Medicine | 2013

Extracorporeal membrane oxygenation instead of invasive mechanical ventilation in patients with acute respiratory distress syndrome

Marius M. Hoeper; Olaf Wiesner; Johannes Hadem; Oliver Wahl; Hendrik Suhling; Christoph Duesberg; W. Sommer; G. Warnecke; Mark Greer; Olaf Boenisch; Markus Busch; Jan T. Kielstein; Andrea S. Schneider; Axel Haverich; Tobias Welte; C. Kühn

Dear Editor, Invasive mechanical ventilation with or without additional extracorporeal membrane oxygenation (ECMO) support represents standard treatment for patients with acute respiratory distress syndrome (ARDS). An ‘‘awake ECMO’’ strategy in order to avoid intubation and mechanical ventilation has been implemented as a bridge to lung transplantation in patients with chronic lung disease [1, 2] but has been used only occasionally in patients with ARDS [3]. We conducted a single-center, uncontrolled pilot trial designed to assess the feasibility of veno-venous ECMO in awake, non-intubated, spontaneously breathing patients with ARDS (www.clinical.govNCT01669 863 ). Patients between 18 and 75 years old presenting with moderate or severe ARDS were eligible. The main exclusion criteria were severe bleeding disorders and uncontrolled sepsis with multi-organ failure involving at least two organ systems. The Institutional Review Board (IRB) of Hannover Medical School approved and supervised the study and all patients provided written informed consent prior to ECMO insertion. Six patients with severe ARDS were enrolled as planned; four of them were immunocompromised. Patient characteristics and outcome parameters are shown in Table 1. All patients suffered from severe ARDS with PaO2/FiO2 ratios at most 100 mmHg while receiving noninvasive ventilation. Gas exchange patterns improved immediately after ECMO insertion and noninvasive ventilation could be stopped within 1 h in two patients. Three patients (patients 1, 4, and 5) were successfully weaned from ECMO after 10, 5, and 7 days, respectively, and discharged from the ICU without needing invasive mechanical ventilation. Patient 2 was also successfully weaned from ECMO support but developed respiratory failure due to an iatrogenic pneumothorax 2 days later and required intubation as a result. A protracted ICU course ensued, complicated by ventilatorassociated pneumonia and sepsis. The patient was eventually discharged from the ICU after 50 days. Patient 3 improved rapidly on ECMO support, but became increasingly agitated and confused. On the 7th day on ECMO support, he intentionally removed his jugular cannula, resulting in emergency intubation and brief cardiopulmonary resuscitation. He subsequently died 10 days later from


American Journal of Transplantation | 2014

Introduction of the lung allocation score in Germany.

Jens Gottlieb; Mark Greer; U. Sommerwerck; T. Deuse; Christian Witt; R. Schramm; C. Hagl; M. Strueber; J. Smits

The aim of this study was to assess performance of the new lung allocation system in Germany based on lung allocation score (LAS). Retrospective analysis of waitlist (WL) outflow, lung transplantation (LTx) activity and 3‐month outcomes comparing 1‐year pre‐ and post‐LAS introduction on December 10, 2011 was performed. Following LAS introduction, WL registrations remained constant, while WL mortality fell by 23% (p = 0.04). Reductions in WL mortality occurred in patients with cystic fibrosis (CF; −52%), emphysema (chronic obstructive pulmonary disease [COPD]; −49%) and pulmonary hypertension (PH; −67%), but not idiopathic pulmonary fibrosis (IPF; +48%). LTx activity increased by 9% (p = 0.146). Compared to pre‐LAS, more patients with IPF (32% vs. 29%) and CF (20% vs. 18%) underwent transplantation and comparatively fewer with COPD (30% vs. 39%). Median LAS among transplant recipients was highest in PH (53) and IPF (49) and lowest in COPD (34). Transplantation under invasive respiratory support increased to 13% (in CF 28%, +85%, p = 0.017). Three‐month survival remained unchanged (pre: 96.1% and post: 94.9%, p = 0.94). Following LAS implementation in Germany, reductions in waiting list size and WL mortality were observed. Composition of transplant recipients changed, with fewer COPD and more IPF recipients. Transplantation under invasive respiratory support increased. Reductions in WL mortality were most pronounced among CF and PH patients.


Respiratory Research | 2011

GDF-15 is abundantly expressed in plexiform lesions in patients with pulmonary arterial hypertension and affects proliferation and apoptosis of pulmonary endothelial cells

Nils Nickel; Danny Jonigk; Tibor Kempf; Clemens L. Bockmeyer; Lavinia Maegel; Johanna Rische; Florian Laenger; Ulrich Lehmann; Clemens Sauer; Mark Greer; Tobias Welte; Marius M. Hoeper; Heiko Golpon

BackgroundGrowth-differentiation factor-15 (GDF-15) is a stress-responsive, transforming growth factor-β-related cytokine, which has recently been reported to be elevated in serum of patients with idiopathic pulmonary arterial hypertension (IPAH). The aim of the study was to examine the expression and biological roles of GDF-15 in the lung of patients with pulmonary arterial hypertension (PAH).MethodsGDF-15 expression in normal lungs and lung specimens of PAH patients were studied by real-time RT-PCR and immunohistochemistry. Using laser-assisted micro-dissection, GDF-15 expression was further analyzed within vascular compartments of PAH lungs. To elucidate the role of GDF-15 on endothelial cells, human pulmonary microvascular endothelial cells (HPMEC) were exposed to hypoxia and laminar shear stress. The effects of GDF-15 on the proliferation and cell death of HPMEC were studied using recombinant GDF-15 protein.ResultsGDF-15 expression was found to be increased in lung specimens from PAH patients, com-pared to normal lungs. GDF-15 was abundantly expressed in pulmonary vascular endothelial cells with a strong signal in the core of plexiform lesions. HPMEC responded with marked upregulation of GDF-15 to hypoxia and laminar shear stress. Apoptotic cell death of HPMEC was diminished, whereas HPMEC proliferation was either increased or decreased depending of the concentration of recombinant GDF-15 protein.ConclusionsGDF-15 expression is increased in PAH lungs and appears predominantly located in vascular endothelial cells. The expression pattern as well as the observed effects on proliferation and apoptosis of pulmonary endothelial cells suggest a role of GDF-15 in the homeostasis of endothelial cells in PAH patients.


American Journal of Transplantation | 2015

Impact of CLAD Phenotype on Survival After Lung Retransplantation: A Multicenter Study

Stijn Verleden; Jamie L. Todd; M. Sato; Scott M. Palmer; Tereza Martinu; Elizabeth N. Pavlisko; Robin Vos; Arne Neyrinck; D. Van Raemdonck; Tomohito Saito; H. Oishi; Shaf Keshavjee; Mark Greer; G. Warnecke; Jens Gottlieb; Axel Haverich

Chronic lung allograft dysfunction (CLAD) remains a major problem after lung transplantation with no definitive treatment except redo lung transplantation (re‐LTx) in selected candidates. However, CLAD is not a homogeneous entity and different phenotypes exist. Therefore, we aimed to evaluate the effect of CLAD phenotypes on survival after re‐LTx for CLAD. Patients who underwent re‐LTx for respiratory failure secondary to CLAD in four LTx centers between 2003 and 2013 were included in this retrospective analysis. Bronchiolitis obliterans syndrome (BOS) and restrictive CLAD (rCLAD) were distinguished using pulmonary function, radiology and explant lung histopathology. Patient variables pre‐ and post‐re‐LTx were collected and analyzed. A total of 143 patients underwent re‐LTx for CLAD resulting in 94 BOS (66%) and 49 rCLAD (34%) patients. Unadjusted and adjusted survival after re‐LTx for rCLAD was worse compared to BOS (HR = 2.60, 1.59–4.24; p < 0.0001 and HR = 2.61, 1.51–4.51; p = 0.0006, respectively). Patients waiting at home prior to re‐LTx experienced better survival compared to hospitalized patients (HR 0.40; 0.23–0.72; p = 0.0022). Patients with rCLAD redeveloped CLAD earlier and were more likely to redevelop rCLAD. Survival after re‐LTx for rCLAD is worse compared to BOS. Consequently, re‐LTx for rCLAD should be critically discussed, particularly when additional peri‐operative risk factors are present.


Journal of Heart and Lung Transplantation | 2014

Early donor-specific antibodies in lung transplantation: risk factors and impact on survival.

F. Ius; W. Sommer; I. Tudorache; C. Kühn; M. Avsar; T. Siemeni; J. Salman; Michael Hallensleben; Daniela Kieneke; Mark Greer; Jens Gottlieb; Axel Haverich; G. Warnecke

BACKGROUND The impact of early donor-specific anti-HLA antibodies (DSA) on patient and graft survival after lung transplantation remains controversial. In this study we analyzed risk factors for DSA that developed before initial hospital discharge after lung transplantation (early DSA) and compared mid-term outcomes in patients with or without DSA. METHODS Between January 2009 and August 2013, 546 patients underwent lung transplantation at our institution. One hundred (18%) patients developed early DSA (Group A) and 446 (82%) patients (Group B) did not. Patient records were retrospectively reviewed. RESULTS Retransplantation (odds ratio [OR] = 2.7, 95% confidence interval [CI] 1.1 to 6.5, p = 0.03), pre-operative HLA antibodies (OR = 2.1, 95% CI 1.2 to 3.4, p = 0.003) and primary graft dysfunction (PGD) score Grade 2 or 3 at 48 hours (OR = 2.6, 95% CI 1.5 to 4.6, p = 0.001) were associated with early DSA development. Overall, 1- and 3-year survival in Group A and B patients was 79 ± 4% vs 88 ± 2% and 57 ± 8% vs 74 ± 3%, respectively (p = 0.019). Eleven Group A (11%) and 32 Group B (7%) patients died before hospital discharge (p = 0.34). Among patients surviving beyond discharge, 1- and 3-year survival in Group A and B patients was 89 ± 4% vs 95 ± 1% and 65 ± 8% vs 80 ± 3% in Group A and B patients, respectively (p = 0.04). Multivariate analysis identified early anti-HLA Class II DSA (OR = 1.9, 95% CI 1.0 to 3.4, p = 0.04) as an independent risk factor for post-discharge mortality but not for in-hospital mortality. CONCLUSIONS Pre-operative HLA antibodies, retransplantation or post-operative PGD increase the risk of developing early DSA, which were independently associated with an increased risk for mortality.


Transplant Infectious Disease | 2014

Course and treatment of chronic hepatitis E virus infection in lung transplant recipients.

Sven Pischke; Mark Greer; Svenja Hardtke; B. Bremer; Anett Gisa; Patrick Lehmann; Axel Haverich; Tobias Welte; Michael P. Manns; Heiner Wedemeyer; Jens Gottlieb

Persistent hepatitis E virus (HEV) infections have been described in various transplant cohorts. However, the frequency and the course of HEV infection in lung transplant recipients (Lu‐Tr) are not well defined.


Journal of Heart and Lung Transplantation | 2016

Five-year experience with intraoperative extracorporeal membrane oxygenation in lung transplantation: Indications and midterm results

F. Ius; W. Sommer; I. Tudorache; M. Avsar; T. Siemeni; J. Salman; Ulrich Molitoris; Clemens Gras; Bjoern Juettner; Jakob Puntigam; Joerg Optenhoefel; Mark Greer; Nicolaus Schwerk; Jens Gottlieb; Tobias Welte; Marius M. Hoeper; Axel Haverich; C. Kuehn; G. Warnecke

BACKGROUND Since April 2010, extracorporeal membrane oxygenation (ECMO) has replaced cardiopulmonary bypass for intraoperative support during lung transplantation at our institution. The aim of this study was to present our 5-year experience with this technique. METHODS Records of patients who underwent transplantation between April 2010 and January 2015 were retrospectively reviewed. Patients who underwent transplantation without ECMO formed Group A. Patients in whom the indication for ECMO support was set a priori before the beginning of the operation formed Group B. The remaining patients in whom the indication for ECMO support was set during transplantation formed Group C. RESULTS Among 595 patients, 425 (71%) patients (Group A) did not require intraoperative ECMO; the remaining 170 (29%) patients did. Among these patients, 95 (56%) patients formed Group B, and the remaining 75 (44%) patients comprised Group C. Pulmonary fibrosis and pre-operative dilated or hypertrophied right ventricle emerged as risk factors for the indication of non-a priori intraoperative ECMO. Patients in Groups B and C showed a higher pre-operative risk profile and higher prevalence of post-operative complications than patients in Group A. Overall survival at 1 year was 93%, 83%, and 82% and at 4 years was 73%, 68%, and 69% in Groups A, B, and C (p = 0.11). The intraoperative use of ECMO did not emerge as a risk factor for in-hospital mortality or mortality after hospital discharge. CONCLUSIONS Intraoperative ECMO filled the gap between pre-operative and post-operative ECMO in lung transplantation. Although complications and in-hospital mortality were higher in patients who received ECMO, survival was similar among patients who underwent transplantation with or without ECMO.


Journal of Heart and Lung Transplantation | 2015

Preemptive treatment with therapeutic plasma exchange and rituximab for early donor-specific antibodies after lung transplantation.

F. Ius; W. Sommer; I. Tudorache; C. Kühn; M. Avsar; T. Siemeni; J. Salman; Michael Hallensleben; Daniela Kieneke; Mark Greer; Jens Gottlieb; Jan T. Kielstein; Dietmar Boethig; Tobias Welte; Axel Haverich; G. Warnecke

OBJECTIVE De novo donor-specific anti-human leukocyte antigen antibodies develop in a high proportion of lung transplant recipients early after lung transplantation. We recently showed that de novo donor-specific antibodies (DSA) occurrence is associated with significantly increased mortality. Here, we studied the efficacy of a preemptive treatment protocol. METHODS A retrospective observational study was conducted on all lung transplantations at Hanover Medical School between January 2009 and May 2013. RESULTS Among the 500 transplant recipients, early DSA developed in 86 (17%). Of these, 56 patients (65%; Group A) received therapeutic plasma exchange, and 30 patients (35%; Group B) did not. Among Group A patients, 51 also received rituximab. Between groups, there was no statistically significant difference in mortality, incidence of pulsed steroid therapies, rejections diagnosed by biopsy specimen, incidence of bronchitis obliterans syndrome (BOS), or infections requiring hospitalization at 1 year and 3 years. Also, there were no statistically significant differences after matching 21 Group A with 21 Group B patients through propensity score analysis. Significantly more Group A patients (65%) than Group B patients (34%) cleared DSA at hospital discharge (p = 0.01). At the last control after transplantation (median, 14 months; interquartile range, 5-24 months), 11 Group A (22%) and 9 Group B patients (33%) still showed DSA (p = 0.28). CONCLUSIONS Preemptive treatment with therapeutic plasma exchange and rituximab led to improved elimination of DSA early after lung transplantation (p = 0.01). However, spontaneous elimination in untreated Group B patients also occurred frequently. This treatment protocol was not associated with significantly improved outcome.

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Tobias Welte

Hannover Medical School

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G. Warnecke

Hannover Medical School

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I. Tudorache

Hannover Medical School

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W. Sommer

Hannover Medical School

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M. Avsar

Hannover Medical School

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F. Ius

Hannover Medical School

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J. Salman

Hannover Medical School

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T. Siemeni

Hannover Medical School

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