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1.
Gigascience ; 132024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38573186

RESUMO

BACKGROUND: Cardiovascular research heavily relies on mouse (Mus musculus) models to study disease mechanisms and to test novel biomarkers and medications. Yet, applying these results to patients remains a major challenge and often results in noneffective drugs. Therefore, it is an open challenge of translational science to develop models with high similarities and predictive value. This requires a comparison of disease models in mice with diseased tissue derived from humans. RESULTS: To compare the transcriptional signatures at single-cell resolution, we implemented an integration pipeline called OrthoIntegrate, which uniquely assigns orthologs and therewith merges single-cell RNA sequencing (scRNA-seq) RNA of different species. The pipeline has been designed to be as easy to use and is fully integrable in the standard Seurat workflow.We applied OrthoIntegrate on scRNA-seq from cardiac tissue of heart failure patients with reduced ejection fraction (HFrEF) and scRNA-seq from the mice after chronic infarction, which is a commonly used mouse model to mimic HFrEF. We discovered shared and distinct regulatory pathways between human HFrEF patients and the corresponding mouse model. Overall, 54% of genes were commonly regulated, including major changes in cardiomyocyte energy metabolism. However, several regulatory pathways (e.g., angiogenesis) were specifically regulated in humans. CONCLUSIONS: The demonstration of unique pathways occurring in humans indicates limitations on the comparability between mice models and human HFrEF and shows that results from the mice model should be validated carefully. OrthoIntegrate is publicly accessible (https://github.com/MarianoRuzJurado/OrthoIntegrate) and can be used to integrate other large datasets to provide a general comparison of models with patient data.


Assuntos
Insuficiência Cardíaca , Humanos , Animais , Camundongos , Insuficiência Cardíaca/genética , Transcriptoma , Volume Sistólico , Metabolismo Energético , RNA
2.
Antioxidants (Basel) ; 13(4)2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38671948

RESUMO

Endothelin-1 is a key regulator of vascular tone and blood pressure in health and disease. We have recently found that ET-1 production in human microvascular endothelial cells (HMECs) can be promoted by angiotensin II (Ang II) through a novel mechanism involving octamer-binding transcription factor-1 (Oct-1), NADPH oxidase-2 (NOX2), and superoxide anions. As the formation of bioactive ET-1 also depends on endothelin-converting enzyme-1 (ECE-1), we investigated the transcriptional regulation of the ECE1 gene. We found that exposure of HMECs to Ang II resulted in a concentration- and time-dependent increase in ECE1 mRNA expression. Pharmacological inhibition of ECE-1 reduced Ang II-stimulated ET-1 release to baseline values. The effect of Ang II on ECE1 mRNA expression was associated with Oct-1 binding to the ECE1 promoter, resulting in its increased activity. Consequently, the Ang II-stimulated increase in ECE1 mRNA expression could be prevented by siRNA-mediated Oct-1 inhibition. It could also be abolished by silencing the NOX2 gene and neutralizing superoxide anions with superoxide dismutase. In mice fed a high-fat diet, cardiac expression of Ece1 mRNA increased in wild-type mice but not in Nox2-deficient animals. It can be concluded that Ang II engages Oct-1, NOX2, and superoxide anions to stimulate ECE1 expression in the endothelium.

3.
J Cardiovasc Dev Dis ; 11(4)2024 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-38667730

RESUMO

BACKGROUND: Minimally invasive aortic valve replacement (AVR) via upper ministernotomy (MiniAVR) is a standard alternative to full sternotomy access. Minimally invasive cardiac surgery has been proven to provide a number of benefits to patients. The aim of this study was to compare the short- and long-term outcomes after MiniAVR versus conventional AVR via full sternotomy (FS) using a biological prosthesis in an elderly higher-risk population. METHODS: Between January 2006 and July 2009, 918 consecutive patients received AVR ± additional procedures with different prostheses at our center. Amongst them, 441 received isolated AVR using a biological prosthesis (median age of 74.5; range: 52-93 years; 50% females) and formed the study population (EuroSCORE II: 3.62 ± 5.5, range: 0.7-42). In total, 137 (31.1%) of the operations were carried out through FS, and 304 (68.9%) were carried out via MiniAVR. Follow-up was complete in 96% of the cases (median of 7.6 years, 6610 patient-years). Propensity score matching (PSM) resulted in two groups of 68 patients with very similar baseline profiles. The primary endpoints were long-term survival, freedom from reoperation, and endocarditis, and the secondary endpoints were early major adverse cardiac and cerebrovascular events (MACCEs). RESULTS: FS led to shorter cardio-pulmonary bypass and aortic cross-clamp durations: 90 (47-194) vs. 100 (46-246) min (p = 0.039) and 57 (33-156) vs. 69 (32-118) min (p = 0.006), respectively. Perioperative stroke occurred in three patients (4.4%; FS) vs. one patient (1.5%; MiniAVR) (p = 0.506). The 30-day mortality was similar in both groups (2.9%, p = 1.000). Survival at 1, 5, and 10 years was 94.1 ± 3% (FS and MiniAVR), 80.3 ± 5% vs. 75.7 ± 5%, and 45.3 ± 6% vs. 43.8 ± 6%, respectively (p = 0.767). There were two (2.9%) reoperations in each group and two thrombo-embolic events (2.9%) vs. one (1.5%) thrombo-embolic event in the MiniAVR and FS groups, respectively (p = 0.596). CONCLUSIONS: In comparison to FS, MiniAVR provided similar short- and long-term outcomes in a higher-risk elderly population receiving biological prostheses. In particular, long-term survival, freedom from reoperation, and the incidence of endocarditis were comparable. These results clearly advocate for the routine use of MiniAVR as a standard procedure for AVR, even in a high-risk population.

4.
N Engl J Med ; 390(17): 1572-1583, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38588025

RESUMO

BACKGROUND: Among low-risk patients with severe, symptomatic aortic stenosis who are eligible for both transcatheter aortic-valve implantation (TAVI) and surgical aortic-valve replacement (SAVR), data are lacking on the appropriate treatment strategy in routine clinical practice. METHODS: In this randomized noninferiority trial conducted at 38 sites in Germany, we assigned patients with severe aortic stenosis who were at low or intermediate surgical risk to undergo either TAVI or SAVR. Percutaneous- and surgical-valve prostheses were selected according to operator discretion. The primary outcome was a composite of death from any cause or fatal or nonfatal stroke at 1 year. RESULTS: A total of 1414 patients underwent randomization (701 to the TAVI group and 713 to the SAVR group). The mean (±SD) age of the patients was 74±4 years; 57% were men, and the median Society of Thoracic Surgeons risk score was 1.8% (low surgical risk). The Kaplan-Meier estimate of the primary outcome at 1 year was 5.4% in the TAVI group and 10.0% in the SAVR group (hazard ratio for death or stroke, 0.53; 95% confidence interval [CI], 0.35 to 0.79; P<0.001 for noninferiority). The incidence of death from any cause was 2.6% in the TAVI group and 6.2% in the SAVR group (hazard ratio, 0.43; 95% CI, 0.24 to 0.73); the incidence of stroke was 2.9% and 4.7%, respectively (hazard ratio, 0.61; 95% CI, 0.35 to 1.06). Procedural complications occurred in 1.5% and 1.0% of patients in the TAVI and SAVR groups, respectively. CONCLUSIONS: Among patients with severe aortic stenosis at low or intermediate surgical risk, TAVI was noninferior to SAVR with respect to death from any cause or stroke at 1 year. (Funded by the German Center for Cardiovascular Research and the German Heart Foundation; DEDICATE-DZHK6 ClinicalTrials.gov number, NCT03112980.).


Assuntos
Estenose da Valva Aórtica , Substituição da Valva Aórtica Transcateter , Idoso , Feminino , Humanos , Masculino , Valva Aórtica/cirurgia , Estenose da Valva Aórtica/cirurgia , Estenose da Valva Aórtica/mortalidade , Próteses Valvulares Cardíacas , Implante de Prótese de Valva Cardíaca/efeitos adversos , Implante de Prótese de Valva Cardíaca/métodos , Implante de Prótese de Valva Cardíaca/mortalidade , Estimativa de Kaplan-Meier , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/mortalidade , Substituição da Valva Aórtica Transcateter/efeitos adversos , Substituição da Valva Aórtica Transcateter/instrumentação , Substituição da Valva Aórtica Transcateter/métodos , Substituição da Valva Aórtica Transcateter/mortalidade , Fatores de Risco , Alemanha
5.
EuroIntervention ; 20(6): e363-e375, 2024 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-38506737

RESUMO

BACKGROUND: There is a lack of comparative data on transcatheter aortic valve implantation (TAVI) in degenerated surgical prostheses (valve-in-valve [ViV]). AIMS: We sought to compare outcomes of using two self-expanding transcatheter heart valve (THV) systems for ViV. METHODS: In this retrospective multicentre registry, we included consecutive patients undergoing transfemoral ViV using either the ACURATE neo/neo2 (ACURATE group) or the Evolut R/PRO/PRO+ (EVOLUT group). The primary outcome measure was technical success according to Valve Academic Research Consortium (VARC)-3. Secondary outcomes were 30-day all-cause mortality, device success (VARC-3), coronary obstruction (CO) requiring intervention, rates of severe prosthesis-patient mismatch (PPM), and aortic regurgitation (AR) ≥moderate. Comparisons were made after 1:1 propensity score matching. RESULTS: The study cohort comprised 835 patients from 20 centres (ACURATE n=251; EVOLUT n=584). In the matched cohort (n=468), technical success (ACURATE 92.7% vs EVOLUT 88.9%; p=0.20) and device success (69.7% vs 73.9%; p=0.36) as well as 30-day mortality (2.8% vs 1.6%; p=0.392) were similar between the two groups. The mean gradients and rates of severe PPM, AR ≥moderate, or CO did not differ between the groups. Technical and device success were higher for the ACURATE platform among patients with a true inner diameter (ID) >19 mm, whereas a true ID ≤19 mm was associated with higher device success - but not technical success - among Evolut recipients. CONCLUSIONS: ViV TAVI using either ACURATE or Evolut THVs showed similar procedural outcomes. However, a true ID >19 mm was associated with higher device success among ACURATE recipients, whereas in patients with a true ID ≤19 mm, device success was higher when using Evolut.


Assuntos
Insuficiência da Valva Aórtica , Bioprótese , Oclusão Coronária , Substituição da Valva Aórtica Transcateter , Humanos , Catéteres , Insuficiência da Valva Aórtica/etiologia , Insuficiência da Valva Aórtica/cirurgia , Valvas Cardíacas , Sistema de Registros , Substituição da Valva Aórtica Transcateter/efeitos adversos
6.
Clin Res Cardiol ; 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38436739

RESUMO

BACKGROUND: In patients not suitable for transfemoral transcatheter aortic valve implantation (TAVI), several access strategies can be chosen. AIM: To evaluate the use and patient outcomes of transaxillary (TAx), transapical (TA), and transaortic (TAo) as alternative access for TAVI in Germany; to further evaluate surgical cutdown vs. percutaneous TAx access. METHODS: All patients entered the German Aortic Valve Registry (GARY) between 2011 and 2019 who underwent non-transfemoral TAVI were included in this analysis. Patients with TA, TAo, or TAx TAVI were compared using a weighted propensity score model. Furthermore, a subgroup analysis was performed for TAx regarding the percutaneous or surgical cutdown approach. RESULTS: Overall, 9686 patients received a non-transfemoral access. A total of 8918 patients (92.1%) underwent TA, 398 (4.1%) TAo, and 370 (3.8%) TAx approaches. Within the TAx subgroup, 141 patients (38.1%) received subclavian cutdown, while 200 (54.1%) underwent a percutaneous approach. The TA patients had a significantly lower 30-day survival than TAx patients (TA 90.92% vs. TAx 95.59%, p = 0.006; TAo 92.22% vs. TAx 95.59%, p = 0.102). Comparing percutaneous and cutdown TAx approaches, no significant differences were seen. However, more vascular complications occurred (TA 1.8%, TAo 2.4%, TAx 12.2%; p < .001), and the hospital length of stay was shorter (TA 12.9 days, TAo 14.1 days, TAx 12 days; p < .001) after TAx access. CONCLUSION: It may be reasonable to consider TAx access first in patients not suitable for TF-TAVI, because the 30-day survival was higher compared with TA access and the 1-year survival was higher compared with TAo access. It remains important for the heart teams to offer alternative access modalities for patients not amenable to the standard TF-TAVI approaches.

7.
Open Heart ; 11(1)2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38388188

RESUMO

INTRODUCTION: Risk stratification based on Euroscore II (ESII) is used in some centres to assist decisions to perform transcatheter aortic valve implant (TAVI) procedures. ESII is a generic, non-TAVI-specific metric, and its performance fades for mortality at follow-up longer than 30 days. We investigated if a TAVI-specific predictive model could achieve improved predictive preinterventional accuracy of 1-year mortality compared with ESII. PATIENTS AND METHODS: In this prospective pilot study, 284 participants with severe symptomatic aortic valve stenosis who underwent TAVI were enrolled. Standard clinical metrics (American Society of Anesthesiology (ASA), New York Heart Association and ESII) and patient-reported outcome measures (EuroQol-5 Dimension-Visual Analogue Scale, Kansas City Cardiomyopathy Questionnaire and Clinical Frailty Scale (CFS)) were assessed 1 day before TAVI. Using these data, we tested predictive models (logistic regression and decision tree algorithm (DTA)) with 1-year mortality as the dependent variable. RESULTS: Logistic regression yielded the best prediction, with ASA and CFS as the strongest predictors of 1-year mortality. Our logistic regression model score showed significantly better prediction accuracy than ESII (area under the curve=0.659 vs 0.800; p=0.002). By translating our results to a DTA, cut-off score values regarding 1-year mortality risk emerged for low, intermediate and high risk. Treatment costs and length of stay (LoS) significantly increased in high-risk patients. CONCLUSIONS AND SIGNIFICANCE: A novel TAVI-specific model predicts 1-year mortality, LoS and costs after TAVI using simple, established, transparent and inexpensive metrics before implantation. Based on this preliminary evidence, TAVI team members and patients can make informed decisions based on a few key metrics. Validation of this score in larger patient cohorts is needed.


Assuntos
Estenose da Valva Aórtica , Substituição da Valva Aórtica Transcateter , Humanos , Estenose da Valva Aórtica/diagnóstico , Estenose da Valva Aórtica/cirurgia , Tempo de Internação , Projetos Piloto , Estudos Prospectivos , Medição de Risco , Fatores de Risco , Resultado do Tratamento , Aprendizado de Máquina
9.
J Microsc ; 293(3): 160-168, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38234217

RESUMO

We calculate a universal shift in work function of 59.4 meV per decade of dopant concentration change that applies to all doped semiconductors and from this use Monte Carlo simulations to simulate the resulting change in secondary electron yield for doped GaAs. We then compare experimental images of doped GaAs layers from scanning electron microscopy and conductive atomic force microscopy. Kelvin probe force microscopy allows to directly measure and map local work function changes, but values measured are often smaller, typically only around half, of what theory predicts for perfectly clean surfaces.

10.
11.
Artigo em Inglês | MEDLINE | ID: mdl-38092063

RESUMO

OBJECTIVE: Spinal cord injury (SCI) with subsequent paraplegia and/or stroke after arch repair with frozen elephant trunk (FET) remain the most devastating complications. In this study, we aim to examine the impact of different cerebral perfusion strategies on the neurological outcome comparing bilateral antegrade cerebral perfusion (bACP) and trilateral antegrade cerebral perfusion (tACP). METHODS: Between 2009 and 2021, 88 patients underwent total arch replacement using a hybrid prosthesis in FET technique for acute (40.4%) and chronic (59.6%) aortic pathologies. After excluding 14 patients who underwent FET with unilateral ACP the remaining 74 patients were divided into two groups. Propensity score matching was performed based on pre- and perioperative patient characteristics resulting in 22 patients in each group. The primary endpoint was a combination of major cerebral event and SCI. Secondary end point was all-cause mortality. RESULTS: Major cerebral events occurred in 9% of the patients in bACP versus 13.6% in tACP group (p = 0.63). No postoperative SCI was observed in patients with bACP and only one patient suffered SCI with tACP (p = 0.31). There was no significant difference in 30-day mortality between the two groups (22.7% in bACP vs. 13.6% in tACP; p = 0.43). CONCLUSION: In patients undergoing total aortic arch repair using FET technique, both perfusion strategies (bilateral and trilateral ACP) are safe and effective. The rates of neurological complications as well as mortalities are acceptably low in both groups. Further studies with larger patient cohorts are warranted.

12.
Clin Res Cardiol ; 113(1): 75-85, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37462856

RESUMO

BACKGROUND: Various second-generation transcatheter heart valve (THV) prostheses with high clinical efficacy and safety are available, but there is limited large-scale data available comparing their hemodynamic performance and clinical implications. OBJECTIVE: To compare the hemodynamic performance and short-term clinical outcome of four second-generation THV prostheses. METHODS: 24,124 patients out of the German Aortic Valve Registry who underwent transfemoral transcatheter aortic valve implantation (TAVI) (Evolut™ R n = 7028, Acurate neo™ n = 2922, Portico n = 878 and Sapien 3 n = 13,296) were included in this analysis. Propensity-score weighted analysis was performed to control for differences in age, left ventricular function, STS score and sex. Primary endpoint was survival at one-year, secondary endpoints were 30 days survival, pre-discharge transvalvular gradients, paravalvular leakage and peri-procedural complications. RESULTS: Thirty-day and one-year survival were not significantly different between the four patient groups. Transvalvular gradients in Evolut™ R and Acurate neo™ were significantly lower as compared to Portico and Sapien 3 at hospital discharge. This difference exists across all annulus sizes. Paravalvular leakage ≥ II occurred significantly less often in the Sapien 3 group (1.2%, p < 0.0001). Rate of severe procedural complications was low and comparable in all groups. Permanent pacemaker implantation rate at one year was lowest in the ACUARATE neo group (13.0%) and highest in the Evolut™ R group (21.9%). CONCLUSION: Albeit comparable short-term clinical outcomes there are certain differences regarding hemodynamic performance and permanent pacemaker implantation rate between currently available THV prostheses which should be considered for individual prosthesis selection.


Assuntos
Estenose da Valva Aórtica , Próteses Valvulares Cardíacas , Substituição da Valva Aórtica Transcateter , Humanos , Valva Aórtica/cirurgia , Estenose da Valva Aórtica/cirurgia , Desenho de Prótese , Resultado do Tratamento , Sistema de Registros
13.
Ann Thorac Surg ; 117(3): 517-525, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37625612

RESUMO

BACKGROUND: Aortic valve (AV) repair is an evolving surgical strategy in the treatment of nonelderly adults with aortic regurgitation. We aimed to determine the 1-year outcome after AV repair vs surgical AV replacement (sAVR) using real-world data from the German Aortic Valve Registry. METHODS: A total of 8076 aortic regurgitation patients (mean age, 59.1 ± 15.0 years; 76% men; mean The Society of Thoracic Surgeons score, 1.3 ± 1.1), who underwent AV surgical procedures between 2011 and 2015, were identified from German Aortic Valve Registry. The AV was repaired in 2327 patients (29%), and the remaining 5749 patients (71%) underwent sAVR. A weighted propensity score model, including the variables of age, sex, and The Society of Thoracic Surgeons score, was used to correct for baseline differences between AV repair and sAVR cohorts. The primary end point was 1-year survival after AV repair vs sAVR. Secondary end points were freedom from cardiac events and AV reinterventions. RESULTS: Survival at 1 year was 97.7% (95% CI, 97.0%-98.5%) in the AV repair cohort vs 96.4% (95% CI, 95.9%-96.9%) in the propensity score-weighted sAVR cohort (log-rank P < .001). Cox regression revealed a significant advantage of AV repair vs sAVR (hazard ratio, 0.68; 95% CI, 0.51-0.90; P < .0001) on 1-year survival, which was independent of age. Cardiac event-free survival at 1 year was 85.7% (95% CI, 483.8%-87.7%) in the AV repair group vs 81.7% (95% CI, 80.7%-82.9%) in the sAVR group (log-rank P < .001). AV reintervention was required in 38 AV repair patients (1.6%) compared with 1.6% in the sAVR cohort (P = .59). CONCLUSIONS: AV repair surgery, whenever intraoperatively feasible, is associated with a significantly better 1-year survival and 1-year cardiac event-free survival compared with sAVR.


Assuntos
Insuficiência da Valva Aórtica , Estenose da Valva Aórtica , Implante de Prótese de Valva Cardíaca , Substituição da Valva Aórtica Transcateter , Masculino , Humanos , Adulto , Pessoa de Meia-Idade , Idoso , Feminino , Valva Aórtica/cirurgia , Substituição da Valva Aórtica Transcateter/métodos , Implante de Prótese de Valva Cardíaca/métodos , Insuficiência da Valva Aórtica/cirurgia , Estenose da Valva Aórtica/cirurgia , Resultado do Tratamento , Fatores de Risco , Sistema de Registros
14.
J Microsc ; 293(3): 169-176, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38112123

RESUMO

Gallium ion (Ga+ ) beam damage induced indium (In) precipitation in indium gallium arsenide (InGaAs)/indium aluminium arsenide (InAlAs) multiple quantum wells and its corresponding evolution under electron beam irradiation was investigated by valence electron energy loss spectroscopy (VEELS) and high-angle annular dark-field imaging (HAADF) in scanning transmission electron microscopy (STEM). Compared with argon ion milling for sample preparation, the heavier projectiles of Ga+ ions pose a risk to trigger In formation in the form of tiny metallic In clusters. These are shown to be sensitive to electron irradiation and can increase in number and size under the electron beam, deteriorating the structure. Our finding reveals the potential risk of formation of In clusters during focused ion beam (FIB) preparation of InGaAs/InAlAs quantum well samples and their subsequent growth under STEM-HAADF imaging, where initially invisible In clusters of a few atoms can move and swell during electron beam exposure.

16.
Biotechnol Adv ; 69: 108276, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37918546

RESUMO

Microbial fermentation processes are expected to play an important role in reducing dependence on fossil-based raw materials for the production of everyday chemicals. In order to meet the growing demand for biotechnological products in the future, alternative carbon sources that do not compete with human nutrition must be exploited. The chemical conversion of the industrially emitted greenhouse gas CO2 into microbially utilizable platform chemicals such as methanol represents a sustainable strategy for the utilization of an abundant carbon source and has attracted enormous scientific interest in recent years. A relatively new approach is the microbial synthesis of products from the C2-compound ethylene glycol, which can also be synthesized from CO2 and non-edible biomass and, in addition, can be recovered from plastic waste. Here we summarize the main chemical routes for the synthesis of methanol and ethylene glycol from sustainable resources and give an overview of recent metabolic engineering work for establishing natural and synthetic microbial assimilation pathways. The different metabolic routes for C1 and C2 alcohol-dependent bioconversions were compared in terms of their theoretical maximum yields and their oxygen requirements for a wide range of value-added products. Assessment of the process engineering challenges for methanol and ethylene glycol-based fermentations underscores the theoretical advantages of new synthetic metabolic routes and advocates greater consideration of ethylene glycol, a C2 substrate that has received comparatively little attention to date.


Assuntos
Dióxido de Carbono , Metanol , Humanos , Dióxido de Carbono/metabolismo , Etilenoglicol/metabolismo , Biotecnologia , Carbono/metabolismo , Engenharia Metabólica
18.
Materials (Basel) ; 16(17)2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37687454

RESUMO

Back-scattered electron imaging and X-ray elemental mapping were combined in a tabletop scanning electron microscope (SEM) to investigate cross-sections of three AA-type (mignon) nickel-metal hydride (NiMH) batteries from different manufacturers. All batteries underwent 500-800 charge/discharge cycles and reached their end of lifetime after several years as they could no longer hold any significant electric charge (less than 20% of nominal charge capacity), but none showed any short-circuiting. The types of degradation observed in this field study included electrode swelling, metallic nickel formation and carbon incorporation into pores in the positive electrodes and, in the negative electrodes, metal alloy segregation of different elements such as nickel, lanthanum and, in one case, sodium, as well as grain break-up and pore formation. All these phenomena could readily be observed at rather small magnifications. This will be important for the improvement of NiMH batteries, for which new generations with nominally slightly increased charge capacities are being marketed all the time.

19.
Ann Thorac Surg ; 2023 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-37717882

RESUMO

BACKGROUND: Whether transcatheter mitral valve replacement (TMVR) devices perform similarly with respect to the underlying mitral regurgitation (MR) etiology remains unknown. The aim of the present analysis was to assess outcomes of TMVR according to the MR underlying etiology among the CHoice of OptImal transCatheter trEatment for Mitral Insufficiency (CHOICE-MI) registry. METHODS: Of 746 patients, 229 patients (30.7%) underwent TMVR. The study population was subdivided according to primary, secondary, or mixed MR. Patients with mitral annular calcification were excluded. The primary study endpoint was a composite endpoint of all-cause mortality or hospitalization for heart failure at 1 year. Secondary study endpoints were all-cause and cardiovascular mortality at 1 year, New York Heart Association functional class, and residual MR, both at discharge and 1 year. RESULTS: The predominant MR etiology was secondary MR (58.4%), followed by primary MR (28.7%) and mixed MR (12.9%). Technical success and procedural mortality were similar according to MR etiology. Discharge echocardiography revealed residual MR 2+ in 11.3%, 3.7%, and 5.3% of patients with primary, secondary, and mixed MR, respectively (P = .1). MR elimination was similar in all groups up to the 1-year follow-up. There was no difference in terms of primary combined outcome occurrence according to MR etiology. One-year all-cause mortality was reported in 28.8%, 24.2%, and 32.1% of patients with primary, secondary, and mixed MR, respectively (P = .07). CONCLUSIONS: In our study we did not find differences in short-term and 1-year outcomes after TMVR according to MR etiology.

20.
EuroIntervention ; 19(8): 652-658, 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37655862

RESUMO

Transcatheter aortic valve implantation (TAVI) has become the preferred treatment option for patients with severe aortic stenosis at increased risk for surgical aortic valve replacement (SAVR) and for older patients irrespective of risk. However, in younger, low-risk patients for whom both therapeutic options, TAVI and SAVR, are applicable, the optimal treatment strategy remains controversial, as data on long-term outcomes remain limited. The DEDICATE-DZHK6 Trial is an investigator-initiated, industry-independent, prospective, multicentre, randomised controlled trial investigating the efficacy and safety of TAVI compared to SAVR in low- to intermediate-risk patients aged 65 years or older. To evaluate both treatment strategies, approximately 1,404 patients determined eligible for both TAVI and SAVR by the interdisciplinary Heart Team were randomised to TAVI or SAVR. Broad inclusion and strict exclusion criteria targeted an all-comers patient population. Procedures were performed according to local best practice with contemporary routine medical devices. The primary endpoints are a composite of mortality or stroke at 1 year and 5 years in order to incorporate midterm efficacy results and complement early safety data. Primary outcomes will be tested sequentially for non-inferiority and superiority. The DEDICATE-DZHK6 Trial has been designed to mirror clinical reality for the treatment of severe aortic stenosis and provide unique information on overall outcomes after TAVI and SAVR that can be directly applied to clinical routines. Its results will help further define optimal treatment strategies for low- to intermediate-risk patients in whom both TAVI and SAVR are currently advisable.

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