Publications by authors named "Lukas Stolz"

15 Publications

  • Page 1 of 1

Cardiac output states in patients with severe functional tricuspid regurgitation: impact on treatment success and prognosis.

Eur J Heart Fail 2021 Jul 16. Epub 2021 Jul 16.

Department of Cardiology, Heart Center Leipzig at University of Leipzig, Leipzig, Germany.

Aims: To investigate whether there is evidence for distinct cardiac output (CO) based phenotypes in patients with chronic right heart failure associated with severe tricuspid regurgitation (TR) and to characterize their impact on TR treatment and outcome.

Methods And Results: A total of 132 patients underwent isolated transcatheter tricuspid valve repair (TTVR) for functional TR at two centres. Patients were clustered according to k-means clustering into low [cardiac index (CI) < 1.7 L/min/m ], intermediate (CI 1.7-2.6 L/min/m ) and high CO (CI > 2.6 L/min/m ) clusters. All-cause mortality and clinical characteristics during follow-up were compared among different CO clusters. Mortality rates were highest for patients in a low (24%) and high CO state (42%, log-rank P < 0.001). High CO state patients were characterized by larger inferior vena cava diameters (P = 0.003), reduced liver function, higher incidence of ascites (P = 0.006) and markedly reduced systemic vascular resistance (P < 0.001) as compared to TTVR patients in other CO states. Despite comparable procedural success rates, the extent of changes in right atrial pressures (P = 0.01) and right ventricular dimensions (P < 0.001) per decrease in regurgitant volume following TTVR was less pronounced in high CO state patients as compared to other CO states. Successful TTVR was associated with the smallest prognostic benefit among low and high CO state patients.

Conclusions: Patients with chronic right heart failure and severe TR display distinct CO states. The high CO state is characterized by advanced congestive hepatopathy, a substantial decrease in peripheral vascular tone, a lack of response of central venous pressures to TR reduction, and worse prognosis. These data are relevant to the pathophysiological understanding and management of this important clinical syndrome.
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http://dx.doi.org/10.1002/ejhf.2307DOI Listing
July 2021

Impact of Residual Mitral Regurgitation on Survival After Transcatheter Edge-to-Edge Repair for Secondary Mitral Regurgitation.

JACC Cardiovasc Interv 2021 Jun 12;14(11):1243-1253. Epub 2021 May 12.

Medizinische Klinik und Poliklinik I, Klinikum der Universität München, Munich, Germany; Munich Heart Alliance, Partner Site German Center for Cardiovascular Disease, Munich, Germany. Electronic address:

Objectives: The aim of this study was to assess the impact of residual mitral regurgitation (resMR) on mortality with respect to left ventricular dilatation (LV-Dil) or right ventricular dysfunction (RV-Dys) in patients with secondary mitral regurgitation (SMR) who underwent mitral valve transcatheter edge-to-edge repair (TEER).

Background: The presence of LV-Dil and RV-Dys correlates with advanced stages of heart failure in SMR patients, which may impact the outcome after TEER.

Methods: SMR patients in a European multicenter registry were evaluated. Investigated outcomes were 2-year all-cause mortality and improvement in New York Heart Association functional class with respect to MR reduction, LV-Dil (defined as LV end-diastolic volume ≥159 ml), and RV-Dys (defined as tricuspid annular plane systolic excursion-to-systolic pulmonary artery pressure ratio of <0.274 mm/mm Hg).

Results: Among 809 included patients, resMR ≤1+ was achieved in 546 (67%) patients. Overall estimated 2-year mortality rate was 32%. Post-procedural resMR was significantly associated with mortality (p = 0.031). Although the improvement in New York Heart Association functional class persisted regardless of either LV-Dil or RV-Dys, the beneficial treatment effect of resMR ≤1+ on 2-year mortality was observed only in patients without LV-Dil and RV-Dys (hazard ratio: 1.75; 95% confidence interval: 1.03 to 3.00).

Conclusions: Achieving optimal MR reduction by TEER is associated with improved survival in SMR patients, especially if the progress in heart failure is not too advanced. In SMR patients with advanced stages of heart failure, as evidenced by LV-Dil or RV-Dys, the treatment effect of TEER on symptomatic improvement is maintained, but the survival benefit appears to be reduced.
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http://dx.doi.org/10.1016/j.jcin.2021.03.050DOI Listing
June 2021

Area Oversizing of Lithium Metal Electrodes in Solid-State Batteries: Relevance for Overvoltage and thus Performance?

ChemSusChem 2021 May 28;14(10):2144. Epub 2021 Apr 28.

Helmholtz Institute Münster, IEK-12, Forschungszentrum Jülich GmbH, Corrensstraße 46, 48149, Münster, Germany.

Invited for this month's cover is the group of Dr. Johannes Kasnatscheew from the Research Center Jülich GmbH. The image shows how area oversizing of lithium can affect the overall power of batteries, in particular at lower temperature. The Full Paper itself is available at 10.1002/cssc.202100213.
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http://dx.doi.org/10.1002/cssc.202100778DOI Listing
May 2021

Sex-Related Clinical Characteristics and Outcomes of Patients Undergoing Transcatheter Edge-to-Edge Repair for Secondary Mitral Regurgitation.

JACC Cardiovasc Interv 2021 Apr 31;14(8):819-827. Epub 2021 Mar 31.

Medizinische Klinik und Poliklinik I, Klinikum der Universität München, Munich, Germany; Munich Heart Alliance, Partner Site German Center for Cardiovascular Disease (DZHK), Munich, Germany. Electronic address:

Objectives: The authors sought to assess sex-based differences in characteristics and outcomes of patients undergoing transcatheter edge-to-edge mitral valve repair (TMVR) for secondary mitral regurgitation (SMR).

Background: Subgroup analysis from the COAPT (Cardiovascular Outcomes Assessment of the MitraClip Percutaneous Therapy for Heart Failure Patients with Functional Mitral Regurgitation) trial indicated potential sex-related differences in outcomes after TMVR. The impact of sex on results after TMVR in a real-world setting is unknown.

Methods: The authors assessed clinical outcomes and echocardiographic parameters in women and men undergoing TMVR for SMR between 2008 and 2018 who were included in the large, international, multicenter real-world EuroSMR registry (European Registry of Transcatheter Repair for Secondary Mitral Regurgitation).

Results: A total of 1,233 patients, including 445 women (36%) and 788 men (64%), were analyzed. Although women were significantly older and had fewer comorbidities than men, TMVR was equally effective in women and men (mitral regurgitation [MR] grade ≤2+ at discharge: 93.2% vs. 94.6% for women vs. men; p = 0.35). All-cause mortality at 1 year (17.9% vs. 18.9%, adjusted hazard ratio: 0.806; p = 0.46) and at 2-year follow-up (26.5% vs. 26.4%, adjusted hazard ratio: 0.757; p = 0.26) were similar in women versus men after multivariate regression analysis. Durability of MR reduction, improvement in symptoms, quality of life, and functional capacity did also not differ during follow-up.

Conclusions: Results from the EuroSMR registry confirmed effective and similar MR reduction with TMVR in women and men. There were no sex-related differences in clinical outcomes up to 2 years of follow-up.
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http://dx.doi.org/10.1016/j.jcin.2020.12.042DOI Listing
April 2021

Percutaneous edge-to-edge repair of severe mitral regurgitation using the MitraClip XTR versus NTR system.

Clin Cardiol 2021 May 24;44(5):708-714. Epub 2021 Mar 24.

Medizinische Klinik und Poliklinik I, University Hospital Munich Campus Grosshadern, Marchioninistraße, München, Deutschland, Germany.

Background: Transcatheter mitral valve repair (TMVR) has shown to improve symptoms and functional capacity in patients with severe mitral valve regurgitation (MR). Novel device developments provide the technology to treat patients with complex anatomies and large coaptation gaps. Nevertheless, the question of superiority of one device remains unanswered. We aimed to compare the MitraClip XTR and MitraClip NTR system in a real world setting.

Hypothesis: TMVR with the MitraClip XTR system is equally effective, but associated with a higher risk of leaflet injury.

Methods: We retrospectively analyzed peri-procedural and mid-term clinical and echocardiographic outcomes of 113 patients treated for severe MR between March 2018 and August 2019 at the University Hospital of Munich.

Results: Postprocedural MR reduction to ≤2+ was comparable in both groups (XTR: 96.1% vs. NTR: 97.6%, p = .38). There was a significant difference in a composite safety endpoint of periprocedural Major adverse cardiac and cerebrovascular events (MACCE) including leaflet injury between groups (XTR 14.6% vs. NTR 1.7%, 95% CI [2.7, 24.6], p = .012). After a median follow-up of 8.5 (4.4, 14.0) months, durable reduction of MR was confirmed (XTR: in 91.9% vs. NTR: 96.8%, p = .31) and clinical and symptomatic improvement was comparable in both groups accordingly.

Conclusion: While efficacy was comparable in both treatment groups, patients treated with the MitraClip XTR systems showed more events of acute leaflet tear and single leaflet device attachment (SLDA). A detailed echocardiographic assessment should be done to identify risk candidates for acute leaflet injury.
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http://dx.doi.org/10.1002/clc.23599DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8119798PMC
May 2021

Area Oversizing of Lithium Metal Electrodes in Solid-State Batteries: Relevance for Overvoltage and thus Performance?

ChemSusChem 2021 May 9;14(10):2163-2169. Epub 2021 Apr 9.

Helmholtz Institute Münster, IEK-12, Forschungszentrum Jülich GmbH, Corrensstraße 46, 48149, Münster, Germany.

Systematic and systemic research and development of solid electrolytes for lithium batteries requires a reliable and reproducible benchmark cell system. Therefore, factors relevant for performance, such as temperature, voltage operation range, or specific current, should be defined and reported. However, performance can also be sensitive to apparently inconspicuous and overlooked factors, such as area oversizing of the lithium electrode and the solid electrolyte membrane (relative to the cathode area). In this study, area oversizing is found to diminish polarization and improves the performance in LiNi Mn Co O (NMC622)||Li cells, with a more pronounced effect under kinetically harsh conditions (e. g., low temperature and/or high current density). For validity reasons, the polarization behavior is also investigated in Li||Li symmetric cells. Given the mathematical conformity of the characteristic overvoltage behavior with the Sand's equation, the beneficial effect is attributed to lower depletion of Li ions at the electrode/electrolyte interface. In this regard, the highest possible effect of area oversizing on the performance is discussed, that is when the accompanied decrease in current density and overvoltage overcomes the Sand's threshold limit. This scenario entirely prevents the capacity decay attributable to Li depletion and is in line with the mathematically predicted values.
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http://dx.doi.org/10.1002/cssc.202100213DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8251826PMC
May 2021

Impact of Right Ventricular Dysfunction on Outcomes After Transcatheter Edge-to-Edge Repair for Secondary Mitral Regurgitation.

JACC Cardiovasc Imaging 2021 04 10;14(4):768-778. Epub 2021 Feb 10.

Department of Cardiology, Medizinische Klinik und Poliklinik I, Klinikum der Universität München, Munich, Germany; Munich Heart Alliance, Partner Site, German Center for Cardiovascular Disease, Munich, Germany. Electronic address:

Objectives: This study sought to assess the impact of right ventricular dysfunction (RVD) as defined by impaired right ventricular-to-pulmonary artery (RV-PA) coupling, on survival after edge-to-edge transcatheter mitral valve repair (TMVR) for severe secondary mitral regurgitation (SMR).

Background: Conflicting data exist regarding the benefit of TMVR in severe SMR. A possible explanation could be differences in RVD.

Methods: Using data from the EuroSMR (European Registry on Outcomes in Secondary Mitral Regurgitation) registry, this study compared the characteristics and outcomes of SMR patients undergoing TMVR, according to their RV-PA coupling, assessed by tricuspid annular plane systolic excursion-to-systolic pulmonary artery pressure (TAPSE/sPAP) ratio.

Results: Overall, 817 patients with severe SMR and available RV-PA coupling assessment underwent TMVR in the participating centers. RVD was present in 211 patients (25.8% with a TAPSE/sPAP ratio <0.274 mm/mm Hg). Although all patients demonstrated significant improvement in their New York Heart Association (NYHA) functional class, there was a trend toward a lower rate of NYHA functional class I or II among patients with RVD (56.5% vs. 65.5%, respectively; p = 0.086) after TMVR. Survival rates at 1 and 2 years were lower among patients with RVD (70.2% vs. 84.0%, respectively; p < 0.001; and 53.4% vs. 73.1%, respectively; p < 0.001). On multivariate analysis, a reduced TAPSE/sPAP ratio was a strong predictor of mortality (odds ratio: 1.62; 95% confidence interval: 1.14 to 2.31; p = 0.007).

Conclusions: RVD, as shown by impairment of RV-PA coupling, is a major predictor of adverse outcome in patients undergoing TMVR for severe SMR. The often neglected functional and anatomic RV parameters should be systematically assessed when planning TMVR procedures for patients with severe SMR.
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http://dx.doi.org/10.1016/j.jcmg.2020.12.015DOI Listing
April 2021

Kinetical threshold limits in solid-state lithium batteries: Data on practical relevance of sand equation.

Data Brief 2021 Feb 23;34:106688. Epub 2020 Dec 23.

Helmholtz-Institute Münster, IEK-12, Forschungszentrum Jülich GmbH, Corrensstraße 46, 48149 Münster, Germany.

The here shown data support the article "The Sand Equation and its Enormous Practical Relevance for Solid-State Lithium Metal Batteries". [1] In this data set, all cells include the poly (ethylene oxide)-based solid polymer electrolyte (PEO-based SPE). The behaviour in symmetric Li||Li cells are provided in a three-electrode cell setup, thus with the use of a reference electrode. Moreover, the Sand behaviour is reported for varied negative electrodes with the focus on polarization onset, defined as transition time. The data of the electrochemical response after the variation of additional parameter, SPE thicknesses, are shown, as well. The theoretical Sand equation is linked with practically obtained values also for varied Li salt concentration. Finally, the discharge behaviour is provided including further charge/discharge cycles with the use of LiNiMnCoO (NMC622) as active material for positive electrodes.
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http://dx.doi.org/10.1016/j.dib.2020.106688DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7786044PMC
February 2021

Conventional Electrolyte and Inactive Electrode Materials in Lithium-Ion Batteries: Determining Cumulative Impact of Oxidative Decomposition at High Voltage.

ChemSusChem 2020 Oct 17;13(19):5301-5307. Epub 2020 Aug 17.

Helmholtz-Institute Münster (HI MS) IEK-12, Forschungszentrum Jülich GmbH, Corrensstrasse 46, 48149, Münster, Germany.

High-voltage electrodes based on, for example, LiNi Mn 0 (LNMO) active material require oxidative stability of inactive materials up to 4.95 V vs. Li|Li . Referring to literature, they are frequently supposed to be unstable, though conclusions are still controversial and clearly depend on the used investigation method. For example, the galvanostatic method, as a common method in battery research, points to the opposite, thus to a stability of the inactive materials, which can be derived from, for example, the high decomposition plateau at 5.56 V vs. Li|Li and stable performance of the LNMO charge/discharge cycling. This work aims to unravel this apparent contradiction of the galvanostatic method with the literature by a thorough investigation of possible trace oxidation reactions in cumulative manner, that is, over many charge/discharge cycles. Indeed, the cumulated irreversible specific capacity amounts to ≈10 mAh g during the initial 50 charge/discharge cycles, which is determined by imitating extreme LNMO high-voltage conditions using electrodes solely consisting of inactive materials. This can explain the ambiguities in stability interpretations of the galvanostatic method and the literature, as the respective irreversible specific capacity is obviously too low for distinct detection in conventional galvanostatic approaches and can be only detected at extreme high-voltage conditions. In this regard, the technique of chronoamperometry is shown to be an effective and proper complementary tool for electrochemical stability research in a qualitative and quantitative manner.
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http://dx.doi.org/10.1002/cssc.202001530DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7589409PMC
October 2020

Elimination of "Voltage Noise" of Poly (Ethylene Oxide)-Based Solid Electrolytes in High-Voltage Lithium Batteries: Linear versus Network Polymers.

iScience 2020 Jun 3;23(6):101225. Epub 2020 Jun 3.

Helmholtz-Institute Münster, IEK-12, Forschungszentrum Jülich GmbH, Corrensstraße 46, 48149 Münster, Germany. Electronic address:

Frequently, poly(ethylene oxide) (PEO)-based solid polymer electrolytes (SPEs) reveal a failure with high-voltage electrodes, e.g. LiNiMnCoO in lithium metal batteries, which can be monitored as an arbitrary appearance of a "voltage noise" during charge and can be attributed to Li dendrite-induced cell micro short circuits. This failure behavior disappears when incorporating linear PEO-based SPE in a semi-interpenetrating network (s-IPN) and even enables an adequate charge/discharge cycling performance at 40°C. An impact of any electrolyte oxidation reactions on the performance difference can be excluded, as both SPEs reveal similar (high) bulk oxidation onset potentials of ≈4.6 V versus Li|Li. Instead, improved mechanical properties of the SPE, as revealed by compression tests, are assumed to be determining, as they mechanically better withstand Li dendrite penetration and better maintain the distance of the two electrodes, both rendering cell shorts less likely.
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http://dx.doi.org/10.1016/j.isci.2020.101225DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7305408PMC
June 2020

Transcatheter Edge-to-Edge Tricuspid Repair for Severe Tricuspid Regurgitation Reduces Hospitalizations for Heart Failure.

JACC Heart Fail 2020 04;8(4):265-276

Medizinische Klinik und Poliklinik I, Klinikum der Universität München, Munich, Germany; Munich Heart Alliance, Partner Site German Center for Cardiovascular Disease (DZHK), Munich, Germany. Electronic address:

Objectives: The goal of this study was to evaluate the effect of transcatheter edge-to-edge tricuspid valve repair (TTVR) for severe tricuspid regurgitation (TR) on hospitalization for heart failure (HHF) and HF-related endpoints.

Background: Patients with severe TR need effective therapies beyond conservative treatment. The impact of TTVR on HHF and HF-related endpoints is unknown.

Methods: Isolated TTVR was performed in 119 patients. Assessments were conducted of New York Heart Association functional class, 6-min walk distance, Minnesota Living with Heart Failure Questionnaire scores, N-terminal pro-B-type natriuretic peptide level, and medication. HHFs were analyzed in the preceding 12 months before and until the longest available follow-up after TTVR. Results were compared with those of 114 patients who underwent combined mitral and tricuspid valve repair.

Results: Procedural success with a reduction to moderate or less TR and no in-hospital death was achieved in 82% of patients. With a median follow-up of 360 days (interquartile range: 187 to 408 days), a durable TR reduction to moderate or less was achieved in 72% of patients (p < 0.001). TTVR reduced the annual rate of HHF by 22% (1.21 to 0.95 HHF/patient-year; p = 0.02), with concomitant clinical improvement in New York Heart Association functional class (patients in class II or lower: 9% to 67%; p < 0.001), 6-min walk distance (+39 m; p = 0.001), and Minnesota Living with Heart Failure Questionnaire score (-6 points; p = 0.02). N-terminal pro-B-type natriuretic peptide level decreased numerically by 783 pg/ml. Diuretic dose before TTVR was increased, but HF medication did not change after TTVR. Procedural success was associated with improved 1-year survival (79% vs. 60%; p = 0.04) and event-free-survival (death + first HHF: 67% vs. 40%; p = 0.001). Transcatheter mitral and tricuspid valve repair-treated patients had comparable outcomes.

Conclusions: TTVR for severe TR is associated with a reduction of HHF and improved clinical outcomes.
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http://dx.doi.org/10.1016/j.jchf.2019.12.006DOI Listing
April 2020

Poly(Ethylene Oxide)-based Electrolyte for Solid-State-Lithium-Batteries with High Voltage Positive Electrodes: Evaluating the Role of Electrolyte Oxidation in Rapid Cell Failure.

Sci Rep 2020 Mar 9;10(1):4390. Epub 2020 Mar 9.

Helmholtz-Institute Münster, IEK-12, Forschungszentrum Jülich GmbH, Corrensstraße 46, 48149, Münster, Germany.

Polyethylene oxide (PEO)-based solid polymer electrolytes (SPEs) typically reveal a sudden failure in Li metal cells particularly with high energy density/voltage positive electrodes, e.g. LiNiMnCoO (NMC622), which is visible in an arbitrary, time - and voltage independent, "voltage noise" during charge. A relation with SPE oxidation was evaluated, for validity reasons on different active materials in potentiodynamic and galvanostatic experiments. The results indicate an exponential current increase and a potential plateau at 4.6 V vs. Li|Li, respectively, demonstrating that the main oxidation onset of the SPE is above the used working potential of NMC622 being < 4.3 V vs. Li|Li. Obviously, the SPE│NMC622 interface is unlikely to be the primary source of the observed sudden failure indicated by the "voltage noise". Instead, our experiments indicate that the Li | SPE interface, and in particular, Li dendrite formation and penetration through the SPE membrane is the main source. This could be simply proven by increasing the SPE membrane thickness or by exchanging the Li metal negative electrode by graphite, which both revealed "voltage noise"-free operation. The effect of membrane thickness is also valid with LiFePO electrodes. In summary, it is the cell set-up (PEO thickness, negative electrode), which is crucial for the voltage-noise associated failure, and counterintuitively not a high potential of the positive electrode.
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http://dx.doi.org/10.1038/s41598-020-61373-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7062893PMC
March 2020
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