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Dive into the research topics where Gerhard Schoen is active.

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Featured researches published by Gerhard Schoen.


European Journal of Cardio-Thoracic Surgery | 2016

Improving outcomes: case-matched comparison of novel second-generation versus first-generation self-expandable transcatheter heart valves

Andreas T. Schaefer; Hendrik Treede; Gerhard Schoen; Florian Deuschl; Niklas Schofer; Yvonne Schneeberger; Stefan Blankenberg; Hermann Reichenspurner; Ulrich Schaefer; Lenard Conradi

OBJECTIVES The published literature has extensively documented clinical benefit derived from transcatheter aortic valve implantation (TAVI) in high-risk patients using self-expanding current-generation transfemoral (TF) transcatheter heart valves (THVs). However, it has also demonstrated apparent shortcomings such as paravalvular leakage (PVL) or need for permanent pacemaker (PM) implantation. We here present a case-matched analysis of acute 30-day outcomes using a novel nitinol-based THV (Symetis Acurate Neo TF™), which may overcome some limitations of currently used devices. METHODS From 2012 to 2015, 69 consecutive patients (study group, 65.2% female, 81.4 ± 6.1 years, logEuroSCORE I 19.9 ± 14.2%) received TF-TAVI using the novel Symetis Acurate Neo TF™ THV. A control group of patients after TF-TAVI with the CoreValve™ THV was retrieved from our database (control group) and matched to the study group utilizing 16 parameters. Data were retrospectively analysed according to updated Valve Academic Research Consortium (VARC-2) definitions. The 30-day follow-up was completed in all cases. RESULTS Apart from gender (65.2 vs 44.9% females, P = 0.023), matching was successful with parameters showing no significant differences. The device success rate was 95.6% (66/69) and 89.9% (62/69) in the study and control groups, respectively (P = 0.20). The all-cause 30-day mortality rate was 5.8% (4/69) vs 10.14% (7/69) (P = 0.36), and disabling stroke was observed in 2.9% (2/69) vs 5.8% (4/69) (P = 0.41), respectively. Resultant transvalvular maximum/mean gradient and effective orifice area (EOA) were 13.8 ± 5.5 vs 18.1 ± 8.1 mmHg (P = 0.001)/7.0 ± 2.8 vs 8.8 ± 4.0 mmHg (P = 0.006) and 1.9 ± 0.3 vs 1.8 ± 0.2 cm(2) (P = 0.015), respectively. PVL ≥grade II was observed in 2.9% (2/69) and 15.94% (11/69) (P = 0.013) of patients and the rate of PM implantation was 8.7% (6/69) vs 44.9% (31/69) (P < 0.001), respectively. DISCUSSION TF-TAVI was feasible and safe using this new type of nitinol-based THV. Superiority to the current generation of self-expanding THVs was achieved regarding post-interventional pressure gradients and EOA, severity of residual PVL and rate of PM implantation. Results set a promising quality standard for TF-TAVI with a self-expanding THV, but will have to be confirmed in a larger patient cohorts for further clinical evaluation.


Clinical Research in Cardiology | 2018

Outcomes with a latest generation self-expandable, intra-annular, re-sheathable transcatheter heart valve system: analysis of patients with impaired left ventricular function and determinants for pacemaker implantation

Andreas T. Schaefer; Niklas Neumann; Matthias Linder; Niklas Schofer; Yvonne Schneeberger; Florian Deuschl; Gerhard Schoen; Stefan Blankenberg; Hermann Reichenspurner; Lenard Conradi; Ulrich Schäfer

ObjectivesWe herein report a single-center experience with the Portico TAVI system. Main focus was set on outcomes in patients with impaired left ventricular (LV) function and predictors for permanent pacemaker (PPM) implantation.MethodsBetween 05/2014 and 10/2017, 106 consecutive patients received TAVI using the Portico device. For comparison of patients with/without impaired LV function, and determination of multi-slice computed tomography and electrocardiogram correlates for PPM implantation subgroups were built (Subgroup I: LVEF ≥ 50%, n = 69, Subgroup II: LVEF < 50%, n = 37; Subgroup A: no PPM implantation, n = 89; Subgroup B: PPM implantation, n = 17). Data were retrospectively analyzed.ResultsDevice success was 95.3% (101/106) with resulting transvalvular peak/mean pressure gradients of 10.6 ± 5.6/5.4 ± 3.1 and PVL ≥ moderate in 5/106 patients (4.7%). 30-day mortality was 4.7% (5/106; subgroup I 3/69, 4.3%; subgroup II 2/37, 5.4%; p = 1.0). Regarding VARC-2 adjudicated clinical endpoints stroke (3/106, 2.8%; subgroups I/II: 2/69 vs. 1/37, p = 1.0) and acute kidney injury (9/106, 8.5%; subgroups I/II: 6/69 vs. 3/37, p = 1.0), no significant differences were found. Postprocedural PPM implantation occurred in 17.9% (19/106) of the patients. Logistic regression for PPM implantation demonstrated predictive character of left coronary cusp (LCC) calcium load in zone 1 (annular plane to coronary ostia) (p = 0.05, threshold 193 mm3) and total calcium load of zone 1 (p = 0.05, threshold 751.2 mm3).ConclusionsThe Portico valve demonstrates a satisfying safety outcome, especially for patients with impaired LV function. Results of the CE-mark trial were confirmed, except for higher PPM rates. PPM rates are in accordance with other reports on this TAVI platform.


Journal of Magnetic Resonance Imaging | 2018

Quantitative T2* relaxation time analysis of articular cartilage of the tibiotalar joint in professional football players and healthy volunteers at 3T MRI

Cyrus Behzadi; Kai‐Jonathan Maas; Goetz Welsch; Michael G. Kaul; Gerhard Schoen; Azien Laqmani; Gerhard Adam; Marc Regier

To compare T2* relaxation times of the tibiotalar cartilage between professional football players and matched healthy male volunteers.


European Journal of Radiology | 2017

Radiation dose reduction during transjugular intrahepatic portosystemic shunt implantation using a new imaging technology

C. Spink; Maxim Avanesov; T. Schmidt; M. Grass; Gerhard Schoen; Gerhard Adam; Peter Bannas; A. Koops

OBJECTIVE To compare patient radiation dose in patients undergoing transjugular intrahepatic portosystemic shunt (TIPS) implantation before and after an imaging-processing technology upgrade. METHODS In our retrospective single-center-study, cumulative air kerma (AK), cumulative dose area product (DAP), total fluoroscopy time and contrast agent were collected from an age- and BMI-matched collective of 108 patients undergoing TIPS implantation. 54 procedures were performed before and 54 after the technology upgrade. Mean values were calculated and compared using two-tailed t-tests. Two blinded, independent readers assessed DSA image quality using a four-rank likert scale and the Wilcoxcon test. RESULTS The new technology demonstrated a significant reduction of 57% of mean DAP (402.8 vs. 173.3Gycm2, p<0.001) and a significant reduction of 58% of mean AK (1.7 vs. 0.7Gy, p<0.001) compared to the precursor technology. Time of fluoroscopy (26.4 vs. 27.8min, p=0.45) and amount of contrast agent (109.4 vs. 114.9ml, p=0.62) did not differ significantly between the two groups. The DSA image quality of the new technology was not inferior (2.66 vs. 2.77, p=0.56). CONCLUSIONS In our study the new imaging technology halved radiation dose in patients undergoing TIPS maintaining sufficient image quality without a significant increase in radiation time or contrast consumption.


European Journal of Radiology | 2017

Comparison of T2* relaxation times of articular cartilage of the knee in elite professional football players and age-and BMI-matched amateur athletes

Cyrus Behzadi; Goetz Welsch; Azien Laqmani; Frank Oliver Henes; Michael G. Kaul; Gerhard Schoen; Gerhard Adam; Marc Regier

OBJECTIVE Recent investigation has underlined the potential of quantitative MR imaging to be used as a complementary tool for the diagnosis of cartilage degeneration at an early state. The presented study analyses T2* relaxation times of articular cartilage of the knee in professional athletes and compares the results to age- and BMI (Body Mass Index)-matched healthy amateur athletes. MATERIALS AND METHODS 22 professional football players and 22 age- and BMI-matched individuals were underwent knee Magnetic Resonance Imaging (MRI) at 3T including qualitative and quantitative analysis. Qualitative analysis included e.g. meniscal tears, joint effusion and bone edema. For quantitative analysis T2* (22 ET: 4.6-53.6ms) measurements in 3D data acquisition were performed. Deep and superficial layers of 22 predefined cartilage segments were analysed. All data sets were postprocessed using a dedicated software tool. Statistical analysis included Student t-test, confidence intervals and a random effects model. RESULTS In both groups, T2* relaxation times were significantly higher in the superficial compared to the deep layers (p<0.001). Professional athletes had significantly higher relaxation times in eight superficial and three deep cartilage layers in the predefined cartilage segments (p<0.05). Highly significant differences were found in the weight-bearing segments of the lateral superficial femoral condyle (p<0.001). CONCLUSION Elevated T2* values in cartilage layers of professional football players compared to amateur athletes were noted. The effects seem to predominate in superficial cartilage layers.


PLOS ONE | 2018

Stentless vs. stented bioprosthesis for aortic valve replacement: A case matched comparison of long-term follow-up and subgroup analysis of patients with native valve endocarditis

Andreas T. Schaefer; Jannis Dickow; Gerhard Schoen; S. Westhofen; Lisa Kloss; Tarik Al-Saydali; Hermann Reichenspurner; Sebastian A. Philipp; Christian Detter

Background Current retrospective evidence suggests similar clinical and superior hemodynamic outcomes of the Sorin Freedom Solo stentless aortic valve (SFS) (LivaNova PLC, London, UK) compared to the Carpentier Edwards Perimount stented aortic valve (CEP) (Edwards Lifesciences Inc., Irvine, California, USA). To date, no reports exist describing case-matched long-term outcomes and analysis for treatment of native valve endocarditis (NVE). Methods From 2004 through 2014, 77 consecutive patients (study group, 59.7% male, 68.9 ± 12.5 years, logEuroSCORE II 7.6 ± 12.3%) received surgical aortic valve replacement (SAVR) with the SFS. A control group of patients after SAVR with the CEP was retrieved from our database and matched to the study group regarding 15 parameters including preoperative endocarditis. Acute perioperative outcomes and follow-up data (mean follow-up time 48.7±29.8 months, 95% complete) were retrospectively analyzed. Results No differences in early mortality occurred during 30-day follow up (3/77; 3.9% vs. 4/77; 5.2%; p = 0.699). Echocardiographic findings revealed lower postprocedural transvalvular pressure gradients (max. 17.0 ± 8.2 vs. 24.5 ± 9.2 mmHg, p< 0.001/ mean pressure of 8.4 ± 4.1 vs. 13.1 ± 5.9 mmHg, p< 0.001) in the SFS group. Structural valve degeneration (SVD) (5.2% vs. 0%; p = 0.04) and valve explantation due to SVD or prosthetic valve endocarditis (PVE) (9.1% vs. 1.3%; p = 0.04) was more frequent in the SFS group. All-cause mortality during follow-up was 20.8% vs. 14.3% (p = 0.397). When patients were divided into subgroups of NVE and respective utilized bioprosthesis, the SFS presented impaired outcomes regarding mortality in NVE cases (p = 0.031). Conclusions The hemodynamic superiority of the SFS was confirmed in this comparison. However, clinical outcomes in terms of SVD and PVE rates, as well as survival after NVE, were inferior in this study. Therefore, we are reluctant to recommend utilization of the SFS for treatment of NVE.


Frontiers in Neurology | 2018

Inverse Perfusion Requirements of Supra- and Infratentorial Brain Metastases Formation

Tanja Schneider; André Kemmling; Julian I. Schroeder; Klaus Pantel; Markus Glatzel; Gerhard Schoen; Malte Mohme; Jens Fiehler; Susanne Gellißen

Background and Aims: Vascular border zones and the gray-white matter junction are preferred sites for the development of brain metastases (BM), whereas microvascular lesions are known to be a protective factor. In this proof of concept study, we aim to study the relationship of blood perfusion and the spatial distribution of BM. Materials and Methods: An average CT perfusion atlas of 107 healthy patients was created. Voxel-wise reference perfusion values were extracted from BM-negative and BM-positive regions in a second cohort of 100 untreated patients harboring 809 BM confirmed by MRI. A comparison of regional perfusion values was performed using the independent t-test. Results: In contrast to supratentorial BM that develop preferably in areas with lower CBV/CBF and longer MTT/TTP compared to the average regional perfusion (p < 0.001), infratentorial BM showed a higher CBV/CBF and shorter MTT/TTP (p < 0.001). Conclusion: Our results imply differing pathophysiological mechanisms underlying supra- and infratentorial BM spreading. The inverse perfusion patterns may result from differences in vascular supply, hemodynamic requirements, and/or production of pro-angiogenic factors.


European Journal of Radiology | 2018

T2 relaxation times of the anterolateral femoral cartilage in patients after ACL-reconstruction with and without a deep lateral femoral notch sign

Cyrus Behzadi; Goetz Welsch; Jan-Philipp Petersen; Bjoern P. Schoennagel; Peter Bannas; Michael G. Kaul; Gerhard Schoen; Josephine Berger-Groch; Gerhard Adam; Marc Regier

PURPOSE To quantitatively assess T2 relaxation times of the anterolateral femoral cartilage following anterior cruciate ligament (ACL)-reconstruction with and without a positive deep lateral femoral notch sign (DLNS) at post-traumatic MRI. MATERIALS AND METHODS In 52 patients post-traumatic MRI as well as 12 months after ACL-rupture (ACLR) and surgical treatment were analysed. In 28 patients a positive DLNS was present at post-traumatic MRI. For quantitative analysis, T2 relaxation time measurements (7 TE: 10-70 ms) were performed at time of re-evaluation. Three polygonal ROIs encompassing the full cartilage layer were placed in the anterolateral femoral cartilage. Clinical assessment included Lysholm-Tegner-Activity-Score, Rasmussens clinical score and modified Cincinnati-Rating-System-Questionnaire. Description and differences were calculated as means and confidence intervals of means, controlled for the cluster effect of person, if appropriate. RESULTS In patients with a positive DLNS after ACLR, relaxation times in the notch region were significantly prolonged compared to patients without a positive DLNS (Δ 7.4 ms, CI: 5.6-9.2; p-value <0.001) as well as to the adjacent anterior (Δ 5.7 ms, CI: 4.7-6.7; p-value <0.001) and central femoral cartilage (Δ 6.6 ms, CI: 5.7-7.6; p-value <0.001). Solely insignificant differences were noticed in the performed clinical scores comparing the two groups (p > 0.05). CONCLUSION Significantly prolonged T2 relaxation times of the anterolateral femoral cartilage were found in patients with a positive DLNS following ACL-reconstruction compared to patients without a DLNS. Based on these results, it has to be assumed that a positive DLNS is associated with higher cartilage degradation.


PLOS ONE | 2017

Perihematomal diffusion restriction as a common finding in large intracerebral hemorrhages in the hyperacute phase

Tanja Schneider; David Frieling; Julian I. Schroeder; Jan Regelsberger; Gerhard Schoen; Jens Fiehler; Susanne Gellißen

Purpose There is growing evidence that a perihematomal area of restricted diffusion (PDR) exists in intraparenchymal hemorrhages (IPH) within 1 week of symptom onset (SO). Here, we study characteristics and the clinical impact of the PDR in patients with hyperacute (≤ 6 hours from SO) IPH by means of apparent diffusion coefficient (ADC). Methods This monocentric, retrospective study includes 83 patients with first-ever primary IPH from 09/2002-10/2015. 3D volumetric segmentation was performed for the IPH, PDR, and perihematomal edema (PHE) on fluid-attenuated inversion recovery, T2*/susceptibility weighted images, and ADC images. Results A PDR was seen in 56/83 patients (67.5%) presenting with hyperacute IPH. Multivariate logistic regression analysis revealed every 10-year increase of age (HR 1.929, 95% CI 1.047–3.552, P = .035) and male gender (HR 5.672, 95% CI 1.038–30.992, P = .045) as significant predictors of the presence of a PDR, but not IPH size, IPH location, nor National Institutes of Health Stroke Scale Score (NIHSS) at admission. We found no difference in NIHSS at discharge, hematoma removal, or mortality rate in PDR-positive patients. ADC values of the PDR show a step-wise normalization with increasing time from SO. Conclusions Occurrence of a PDR is a common finding in supratentorial hyperacute IPH, but shows no adverse short-term clinical impact. It may represent transient oligemic and metabolic changes.


PLOS ONE | 2017

Edema is not a reliable diagnostic sign to exclude small brain metastases

Tanja Schneider; Jan Felix Kuhne; Paul Bittrich; Julian Schroeder; Tim Magnus; Malte Mohme; Malte Grosser; Gerhard Schoen; Jens Fiehler; Susanne Siemonsen

No prior systematic study on the extent of vasogenic edema (VE) in patients with brain metastases (BM) exists. Here, we aim to determine 1) the general volumetric relationship between BM and VE, 2) a threshold diameter above which a BM shows VE, and 3) the influence of the primary tumor and location of the BM in order to improve diagnostic processes and understanding of edema formation. This single center, retrospective study includes 173 untreated patients with histologically proven BM. Semi-manual segmentation of 1416 BM on contrast-enhanced T1-weighted images and of 865 VE on fluid-attenuated inversion recovery/T2-weighted images was conducted. Statistical analyses were performed using a paired-samples t-test, linear regression/generalized mixed-effects model, and receiver-operating characteristic (ROC) curve controlling for the possible effect of non-uniformly distributed metastases among patients. For BM with non-confluent edema (n = 545), there was a statistically significant positive correlation between the volumes of the BM and the VE (P < 0.001). The optimal threshold for edema formation was a diameter of 9.4 mm for all BM. The primary tumors as interaction term in multivariate analysis had a significant influence on VE formation whereas location had not. Hence VE development is dependent on the volume of the underlying BM and the site of the primary neoplasm, but not from the location of the BM.

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