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1.
Circ Cardiovasc Interv ; : e013794, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38629311

RESUMO

BACKGROUND: The extent of cardiac damage and its association with clinical outcomes in patients undergoing transcatheter edge-to-edge repair (TEER) for degenerative mitral regurgitation remains unclear. This study was aimed to investigate cardiac damage in patients with degenerative mitral regurgitation treated with TEER and its association with outcomes. METHODS: We analyzed patients with degenerative mitral regurgitation treated with TEER in the Optimized Catheter Valvular Intervention-Mitral registry, which is a prospective, multicenter observational data collection in Japan. The study subjects were classified according to the extent of cardiac damage at baseline: no extravalvular cardiac damage (stage 0), mild left ventricular or left atrial damage (stage 1), moderate left ventricular or left atrial damage (stage 2), or right heart damage (stage 3). Two-year mortality after TEER was compared using Kaplan-Meier analysis. RESULTS: Out of 579 study participants, 8 (1.4%) were classified as stage 0, 76 (13.1%) as stage 1, 319 (55.1%) as stage 2, and 176 (30.4%) as stage 3. Two-year survival was 100% in stage 0, 89.5% in stage 1, 78.9% in stage 2, and 75.3% in stage 3 (P=0.013). Compared with stage 0 to 1, stage 2 (hazard ratio, 3.34 [95% CI, 1.03-10.81]; P=0.044) and stage 3 (hazard ratio, 4.51 [95% CI, 1.37-14.85]; P=0.013) were associated with increased risk of 2-year mortality after TEER. Significant reductions in heart failure rehospitalization rate and New York Heart Association functional scale were observed following TEER (both, P<0.001), irrespective of the stage of cardiac damage. CONCLUSIONS: Advanced cardiac damage is associated with an increased risk of mortality in patients undergoing TEER for degenerative mitral regurgitation. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: UMIN000023653.

2.
ESC Heart Fail ; 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38607328

RESUMO

AIMS: A considerable proportion of candidates for transcatheter aortic valve implantation (TAVI) have underlying heart failure (HF) with preserved ejection fraction (HFpEF), which can be challenging for diagnosis because significant valvular heart disease should be excluded before diagnosing HFpEF. This study investigated the long-term prognostic value of the pre-procedural H2FPEF score in patients with preserved ejection fraction (EF) undergoing TAVI. METHODS AND RESULTS: Patients who underwent TAVI between October 2013 and May 2017 were enrolled from the Optimized CathEter vAlvular iNtervention-Transcatheter Aortic Valve Implantation Japanese multicentre registry. After excluding 914 patients, 1674 patients with preserved EF ≥ 50% (median age: 85 years, 72% female) were selected for calculation of the H2FPEF score and were dichotomized into two groups: the low H2FPEF score [0-5 points; n = 1399 (83.6%)] group and the high H2FPEF score [6-9 points; n = 275 (16.4%)] group. Patients with high H2FPEF scores were associated with a higher prevalence of New York Heart Association Functional Class III/IV (59.3% vs. 43.7%, P < 0.001), diabetes (24.4% vs. 18.5%, P = 0.03), and paradoxical low-flow, low-gradient aortic stenosis (15.9% vs. 6.2%, P < 0.001). These patients showed worse prognoses than those with low H2FPEF scores regarding the cumulative 2 year all-cause mortality (26.3% vs. 15.5%, log-rank P < 0.001), cardiovascular mortality (10.5% vs. 5.4%, log-rank P < 0.001), HF hospitalization (16.2% vs. 6.7%, log-rank P < 0.001), and the composite endpoint of cardiovascular mortality and HF hospitalization (23.8% vs. 10.8%, log-rank P < 0.001). After adjustment for several confounders, the high H2FPEF scores were independently associated with increased risk for all-cause mortality [adjusted hazard ratio (HR), 1.48; 95% confidence interval (CI), 1.09-2.00; P = 0.011] and for the composite endpoint of cardiovascular mortality and HF hospitalization (adjusted HR, 1.95; 95% CI, 1.38-2.74; P < 0.001). Subgroup analysis confirmed the excess risk of high H2FPEF scores relative to low H2FPEF scores for the composite endpoint of cardiovascular mortality and HF hospitalization increased with a lower Society of Thoracic Surgeons (STS) score (STS score <8%: adjusted HR, 2.40; 95% CI, 1.50-3.85; P < 0.001; STS score ≥8%: adjusted HR, 1.34; 95% CI, 0.79-2.28; P = 0.28; Pinteraction = 0.030). CONCLUSIONS: The H2FPEF score is useful for predicting long-term adverse outcomes after TAVI, including all-cause mortality, cardiovascular mortality, and HF hospitalization for patients with preserved EF. More aggressive interventions targeting HFpEF in addition to the TAVI procedure might be relevant in patients with high H2FPEF scores, particularly in those with a lower surgical risk.

3.
JACC Asia ; 4(4): 306-319, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38660100

RESUMO

Background: Few reports on pre-existing left bundle branch block (LBBB) in patients undergoing transcatheter aortic valve replacement (TAVR) are currently available. Further, no present studies compare patients with new onset LBBB with those with pre-existing LBBB. Objectives: This study aimed to investigate the association between pre-existing or new onset LBBB and clinical outcomes after TAVR. Methods: Using data from the Japanese multicenter registry, 5,996 patients who underwent TAVR between October 2013 and December 2019 were included. Patients were classified into 3 groups: no LBBB, pre-existing LBBB, and new onset LBBB. The 2-year clinical outcomes were compared between 3 groups using Cox proportional hazards models and propensity score analysis to adjust the differences in baseline characteristics. Results: Of 5,996 patients who underwent TAVR, 280 (4.6%) had pre-existing LBBB, while 1,658 (27.6%) experienced new onset LBBB. Compared with the no LBBB group, multivariable Cox regression analysis showed that pre-existing LBBB was associated not only with a higher 2-year all-cause (adjusted HR: 1.39; 95% CI: 1.06-1.82; P = 0.015) and cardiovascular (adjusted HR: 1.60; 95% CI: 1.04-2.48; P = 0.031) mortality, but also with higher all-cause (adjusted HR: 1.43, 95% CI: 1.07-1.91; P = 0.016) and cardiovascular (adjusted HR: 1.81, 95% CI:1.12-2.93; P = 0.014) mortality than the new onset LBBB group. Heart failure was the most common cause of cardiovascular death, with more heart failure deaths in the pre-existing LBBB group. Conclusions: Pre-existing LBBB was independently associated with poor clinical outcomes, reflecting an increased risk of cardiovascular mortality after TAVR. Patients with pre-existing LBBB should be carefully monitored.

4.
Chem Sci ; 15(6): 1953-1965, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38332834

RESUMO

Precise template synthesis will realize three-dimensionally ordered nanoporous graphenes (NPGs) with a spatially controlled seamless graphene structure and fewer edges. These structural features result in superelastic nature, high electrochemical stability, high electrical conductivity, and fast diffusion of gases and ions at the same time. Such innovative 3D graphene materials are conducive to solving energy-related issues for a better future. To further improve the attractive properties of NPGs, we review the template synthesis and its mechanism by chemical vapor deposition of hydrocarbons, analysis of the nanoporous graphene structure, and applications in electrochemical and mechanical devices.

5.
J Clin Med ; 13(3)2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38337545

RESUMO

Background: Transcatheter edge-to-edge mitral valve repair (TEER) has emerged as a viable approach to addressing substantial secondary mitral regurgitation. In the contemporary landscape where ultimate heart failure-specific therapies, such as cardiac replacement modalities, are available, prognosticating a high-risk cohort susceptible to early cardiac mortality post-TEER is pivotal for formulating an effective therapeutic regimen. Methods: Our study encompassed individuals with secondary mitral regurgitation and chronic heart failure enlisted in the multi-center (Optimized CathEter vAlvular iNtervention (OCEAN)-Mitral registry. We conducted an assessment of baseline variables associated with cardiac death within one year following TEER. Results: Amongst the 1517 patients (median age: 78 years, 899 males), 101 experienced cardiac mortality during the 1-year observation period after undergoing TEER. Notably, a history of heart failure-related admissions within the preceding year, utilization of intravenous inotropes, and elevated plasma B-type natriuretic peptide levels emerged as independent prognosticators for the primary outcome (p < 0.05 for all). Subsequently, we devised a novel risk-scoring system encompassing these variables, which significantly stratified the cumulative incidence of the 1-year primary outcome (16%, 8%, and 4%, p < 0.001). Conclusions: Our study culminated in the development of a new risk-scoring system aimed at predicting 1-year cardiac mortality post-TEER.

6.
Open Heart ; 11(1)2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38417913

RESUMO

OBJECTIVES: The clinical outcomes of transcatheter aortic valve replacement (TAVR) in patients with aortic stenosis (AS) and concomitant active cancer remain insufficiently explored. This study aimed to assess the midterm outcomes of TAVR in patients diagnosed with AS and active cancer. METHODS: Data from the OCEAN-TAVI, a prospective Japanese registry of TAVR procedures, was analysed to compare prognoses and clinical outcomes in patients with and without active cancer at the time of TAVR. RESULTS: Of the 2336 patients who underwent TAVR from October 2013 to July 2017, 89 patients (3.8%) had active cancer, whereas 2247 did not. Among patients with active cancer, 49 had limited-stage cancer (stage 1 or 2). The prevalent cancers identified before TAVR were colon (21%), prostate (18%), lung (15%), liver (11%) and breast (9%). Although the periprocedural complications and 30-day mortality rates were comparable between the groups, the 3-year survival rate after TAVR was notably lower in patients with active cancer (64.7%) than in those without active cancer (74.7%; p=0.016). Nevertheless, the 3-year survival rate of patients with limited-stage cancer (stage 1 or 2) did not significantly differ from those without cancer (70.6% vs 74.7%, p=0.50). CONCLUSIONS: The patients with active cancer exhibited significantly reduced midterm survival rates. However, no distinct disparity existed in those with limited-stage cancer (stage 1 or 2). Although TAVR is a viable treatment in patients with AS with active cancer, the type and stage of cancer and prognosis should be carefully weighed in the decision-making process.


Assuntos
Estenose da Valva Aórtica , Neoplasias , Substituição da Valva Aórtica Transcateter , Masculino , Humanos , Substituição da Valva Aórtica Transcateter/métodos , Resultado do Tratamento , Estudos Prospectivos , Fatores de Tempo , Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/cirurgia , Neoplasias/diagnóstico
8.
JACC Asia ; 3(5): 766-773, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38094997

RESUMO

Background: Transcatheter edge-to-edge repair (TEER) is a less invasive treatment for patients with mitral regurgitation (MR). Limited safety and efficacy data of TEER with MitraClip, including the fourth-generation (G4) system, in a large cohort, are available. Objectives: This study aimed to summarize the initial experience of the TEER system in patients with MR from a large registry in Japan. Methods: The OCEAN (Optimized CathEter vAlvular iNtervention)-Mitral Registry is an ongoing, prospective, investigator-initiated, multicenter, observational registry for patients with primary and secondary MR undergoing transcatheter mitral valve therapies. A total of 21 centers participated in the registry. Patients undergoing TEER were enrolled, and their characteristics, procedural details, and clinical outcomes were recorded. Results: In total, 2,150 patients including 1,605 patients (75.0%) with secondary MR, were enrolled between April 2018 and June 2021. The median age was 80 years, and 43.7% were women. The median device and fluoroscopy times were 60 and 26 minutes, respectively. Those with the G4 system (618/2,150 [28.7%]) were significantly shorter than those with the second generation (G2) system (1,532/2,150 [71.3%]). Overall, 94.6% met acute procedural success without significant differences between the 2 systems (G2 94.7% vs G4 94.6%; P = 0.961). Conclusions: The OCEAN-Mitral registry has demonstrated the short-term outcomes of TEER systems, including the G4 system, in symptomatic patients with primary and secondary MR. The acute procedural success rate in the G2 system was excellent, and that in the G4 system was expected to improve with the multidisciplinary heart valve team approach. (Japanese Registry study of valvular heart diseases treatment and prognosis; UMIN000023653).

9.
J Clin Med ; 12(23)2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38068484

RESUMO

BACKGROUND: Individuals with heart failure displaying supra-normal left ventricular ejection fraction (snLVEF) may exhibit less favorable clinical outcomes in contrast to their counterparts with normal left ventricular ejection fraction (nLVEF). The distinctive characteristics and mid-term prognosis of individuals with severe aortic stenosis and snLVEF following transcatheter aortic valve replacement (TAVR) remain enigmatic. METHODS: Among 7393 patients diagnosed with severe aortic stenosis who underwent TAVR between 2013 and 2019 and were enlisted in the optimized transcatheter valvular intervention (OCEAN-TAVI) multicenter registry (UMIN000020423), we selected patients with left ventricular ejection fraction (LVEF) ≥ 50%. snLVEF was defined as LVEF exceeding 65%. We compared the baseline characteristics and assessed three-year post-TAVR mortality and heart failure readmission rates between the snLVEF (LVEF > 65%) and nLVEF cohorts (LVER 50-65%). RESULTS: Our study cohort comprised 5989 patients (mean age 84.4 ± 5.1 years and 1783 males). Among these, 2819 patients were categorized within the snLVEF cohort, while the remaining 3170 were allocated to the nLVEF group. Individuals within the snLVEF cohort were more likely to be female and displayed lower levels of natriuretic peptides, as well as smaller left ventricular dimensions in comparison to their nLVEF counterparts (p < 0.05 for all). The presence of snLVEF emerged as an independent predictor of the three-year composite endpoint relative to nLVEF, with an adjusted hazard ratio of 1.16 (95% confidence interval 1.02-1.31, p = 0.023) after accounting for several potential confounding factors. CONCLUSIONS: snLVEF was relatively common among candidates for TAVR with preserved ejection fraction. Patients harboring snLVEF appear to manifest a distinctive clinical profile and encounter less favorable clinical outcomes following TAVR in contrast to those characterized by nLVEF.

10.
Phys Chem Chem Phys ; 25(48): 32972-32978, 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38019669

RESUMO

Nanoporous graphene (NPG) materials have the pronounced electrochemical stability of the seamless graphene structures developed over the 3D space. We revisited the Raman spectra of nanoporous carbons (NPCs) synthesized using θ-/γ-Al2O3 templates and NPGs converted from NPCs by annealing at 1800 °C to identify the type and density of defects. We found that both the NPCs and NPGs mostly consist of single-layered graphene with a few single vacancies and Stone-Wales defects. The density of vacancy defect per hexagon in the graphene sheet is estimated to be 10-2 for NPCs, while the annealing reduced the value to 10-3-10-4 for NPGs. This supports the outstanding chemical and electrochemical stability of the novel porous carbon materials.

11.
Eur Heart J Case Rep ; 7(11): ytad503, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37954569

RESUMO

Background: We previously reported a case of successful percutaneous left atrial appendage closure (LAAC) for complex left atrial appendage (LAA) morphology using a handmade double-curve delivery sheath (DS) reshaped by a heat gun. However, whether the reshaped curve was appropriately adjusted as an optimal configuration for this patient's anatomy remained uncertain. Case summary: We established the LAAC procedural simulation model supported by virtual reality (VR) technology. With this VR simulator, the patient's whole heart model with venous access route and atrial septal puncture point of foramen ovale (FO) could be replicated based on the pre-procedural computed tomography image. Multiple views of the VR image provided a deep understanding of the patient-specific anatomy. Additionally, the operators were enabled to perform the virtual LAAC procedure using VR-derived LAAC devices, including various DS types. In the VR simulator, the manually reshaped DS showed better co-axiality from the FO to the LAA orifice than the conventional double-curve DS, resulting in the successful deployment inside the LAA of the VR simulator. However, the perpendicularity of the device towards the LAA orifice of the handmade reshaped DS remained insufficient. The VR simulator suggested that the ideal curve of the DS needed to change relatively posteriorly and have a more aggressive inferior slide than the previously reshaped DS. Discussion: The post-procedural review of the VR simulator confirmed that the sheath reshaping technique helped ensure successful LAAC. Pre-procedural VR simulation may be useful for procedural planning that includes DS reshaping for patients with challenging anatomy undergoing LAAC.

12.
Contemp Clin Trials ; 134: 107358, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37852534

RESUMO

BACKGROUND: Despite the wide implementation of transcatheter aortic valve implantation (TAVI), the optimal antithrombotic therapy after TAVI has not been established yet. Owing to the accumulating evidence supporting the efficacy and safety of single antiplatelet therapy (SAPT) over dual antiplatelet therapy, the latest guideline recommends life-long SAPT. However, there is scarce evidence supporting SAPT compared with non-antithrombotic therapy. Given the vulnerability of patients undergoing TAVI in terms of high bleeding risk, the benefit of SAPT may be canceled out by its potential increased bleeding risk. STUDY DESIGN AND OBJECTIVES: Non-antithrombotic Therapy After Transcatheter Aortic Valve Implantation (NAPT) Trial is a prospective, randomized controlled, open-label blinded endpoint multicenter trial conducted in Japan, testing the non-inferiority of non-antithrombotic therapy compared with aspirin monotherapy in patients who underwent TAVI and had no indications for long-term oral anticoagulation therapy (OAC). Patients who successfully underwent trans-femoral TAVI for severe aortic stenosis with either balloon-expandable or self-expandable valves are eligible for inclusion. Key exclusion criteria are (i) occurrence of perioperative complications (ii) indications of taking antithrombotic drugs for other reasons; (iii) eGFR <30 ml/min/1.73 m2 or hemodialysis or peritoneal dialysis. A total of 360 patients will be randomized (1:1) to aspirin monotherapy vs. non-antithrombotic therapy. The primary outcome is a composite of all-cause mortality, myocardial infarction, stroke, and bleeding. All bleeding events based on the Valve Academic Research Consortium 3 are included as a component of the primary outcome. CONCLUSION: The NAPT trial will determine the non-inferiority of a non-antithrombotic therapy compared with aspirin monotherapy after TAVI.


Assuntos
Estenose da Valva Aórtica , Substituição da Valva Aórtica Transcateter , Humanos , Substituição da Valva Aórtica Transcateter/efeitos adversos , Inibidores da Agregação Plaquetária/efeitos adversos , Estudos Prospectivos , Estenose da Valva Aórtica/cirurgia , Estenose da Valva Aórtica/tratamento farmacológico , Estenose da Valva Aórtica/etiologia , Aspirina/uso terapêutico , Resultado do Tratamento
13.
J Am Heart Assoc ; 12(20): e030747, 2023 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-37815039

RESUMO

Background Limited data are available about clinical outcomes and residual mitral regurgitation (MR) after transcatheter edge-to-edge repair in the large Asian-Pacific cohort. Methods and Results From the Optimized Catheter Valvular Intervention (OCEAN-Mitral) registry, a total of 2150 patients (primary cause of 34.6%) undergoing transcatheter edge-to-edge repair were analyzed and classified into 3 groups according to the residual MR severity at discharge: MR 0+/1+, 2+, and 3+/4+. The mortality and heart failure hospitalization rates at 1 year were 12.3% and 15.0%, respectively. Both MR and symptomatic improvement were sustained at 1 year with MR ≤2+ in 94.1% of patients and New York Heart Association functional class I/II in 95.0% of patients. Compared with residual MR 0+/1+ (20.4%) at discharge, both residual MR 2+ (30.2%; P < 0.001) and 3+/4+ (32.4%; P = 0.007) were associated with the higher incidence of death or heart failure hospitalization (adjusted hazard ratio [HR], 1.59; P < 0.001, and adjusted HR, 1.73; P = 0.008). New York Heart Association class III/IV at 1 year was more common in the MR 3+/4+ group (20.0%) than in the MR 0+/1+ (4.6%; P < 0.001) and MR 2+ (6.4%; P < 0.001) groups, and the proportion of New York Heart Association class I is significantly higher in the MR 1+ group (57.8%) than in the MR 2+ group (48.3%; P = 0.02). Conclusions The OCEAN-Mitral registry demonstrated favorable clinical outcomes and sustained MR reduction at 1 year in patients undergoing transcatheter edge-to-edge repair. Both residual MR 2+ and 3+/4+ after transcatheter edge-to-edge repair at discharge were associated with worse clinical outcomes compared with residual MR 0+/1+. Registration Information https://upload.umin.ac.jp. Identifier: UMIN000023653.


Assuntos
Insuficiência Cardíaca , Implante de Prótese de Valva Cardíaca , Próteses Valvulares Cardíacas , Insuficiência da Valva Mitral , Humanos , Valva Mitral/diagnóstico por imagem , Valva Mitral/cirurgia , Implante de Prótese de Valva Cardíaca/métodos , Fatores de Risco , Resultado do Tratamento , Cateterismo Cardíaco/efeitos adversos , Hemodinâmica , Sistema de Registros
16.
Am J Cardiol ; 207: 150-158, 2023 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-37741105

RESUMO

Prevalent and incident atrial fibrillation are common in patients who undergo transcatheter aortic valve implantation and are associated with impaired postprocedural outcomes, including mortality. We determined predictors of long-term mortality in patients with atrial fibrillation after successful transcatheter aortic valve implantation. The EdoxabaN Versus standard of care and theIr effectS on clinical outcomes in pAtients havinG undergonE Transcatheter Aortic Valve Implantation-Atrial Fibrillation (ENVISAGE-TAVI AF) trial (NCT02943785) was a multicenter, prospective, randomized controlled trial in patients with prevalent or incident atrial fibrillation after successful transcatheter aortic valve implantation who received edoxaban or vitamin K antagonists. A Cox proportional hazard model was performed to identify predictors of all-cause mortality using a stepwise approach for multiple regression analysis. In addition, we assessed the performance of different risk scores and prediction models using ENVISAGE-TAVI AF data. Of 1,426 patients in ENVISAGE-TAVI AF, 178 (12.5%) died during the follow-up period (median 548 days). Our stepwise approach identified greater risk of mortality with older age, impaired renal function, nonparoxysmal atrial fibrillation, excessive alcohol use, New York Heart Association heart failure class III/IV, peripheral artery disease, and history of major bleeding or predisposition to bleeding. The present model (concordance statistic [c-statistic] 0.67) was a better discriminator than were other frequently used risk scores, such as the Society of Thoracic Surgeons score (c-statistic 0.56); Congestive heart failure, Hypertension, Age ≥75, Diabetes, Stroke, Vascular disease, Age 65 to 74 years, and Sex category (CHA2DS2-VASc) score (c-statistic 0.54); or Hypertension, Abnormal renal/liver function, Stroke, Bleeding history or predisposition, Labile international normalized ratio, Elderly, and Drugs/alcohol concomitantly (HAS-BLED) score (c-statistic 0.58). In ENVISAGE-TAVI AF, several modifiable and nonmodifiable clinical characteristics were significantly associated with greater long-term all-cause mortality. Improved risk stratification to estimate the probability of mortality after successful transcatheter aortic valve implantation in patients with atrial fibrillation may improve long-term patient prognosis.


Assuntos
Estenose da Valva Aórtica , Fibrilação Atrial , Hipertensão , Acidente Vascular Cerebral , Substituição da Valva Aórtica Transcateter , Idoso , Humanos , Valva Aórtica/cirurgia , Estenose da Valva Aórtica/complicações , Estenose da Valva Aórtica/cirurgia , Fibrilação Atrial/cirurgia , Hemorragia/etiologia , Hipertensão/complicações , Estudos Prospectivos , Fatores de Risco , Acidente Vascular Cerebral/etiologia , Substituição da Valva Aórtica Transcateter/efeitos adversos , Resultado do Tratamento , Masculino , Feminino
17.
Inorg Chem ; 62(36): 14580-14589, 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37638697

RESUMO

The selective formation of meta-stable Fe3O4 from ferrous sources by suppressing its oxidative conversion to the most stable hematite (α-Fe2O3) is challenging under oxidative conditions for solid-state synthesis. In this work, we investigated the conversion of iron(II) chloride (FeCl2) to magnetite (Fe3O4) under inert atmosphere in the presence of steam, and the obtained oxides were analyzed by atomic-resolution TEM, 57Fe Mössbauer spectroscopy, and the Verwey transition temperature (Tv). The reaction proceeded in two steps, with H2O as the oxide source in the initial step and as an oxidant in the second step. The initial hydrolysis occurred at temperatures higher than 120 °C to release gaseous HCl, via substituting lattice chloride Cl- with oxide O2-, to give iron oxide intermediates. In the first step, the construction of the intermediate oxides was not topotactic. The second step as a kinetic bottleneck occurred at temperatures higher than 350 °C to generate gaseous H2 through the oxidation of FeII by H+. A substantially large kinetic isotope effect (KIE) was observed for the second step at 500 °C, and this indicates the rate-determining step is the hydrogen evolution. Quantitative analysis of evolved H2 revealed that full conversion of ferrous chloride to magnetite at 500 °C was followed by additional oxidation of the outer sphere of magnetite to give a Fe2O3 phase, as supported by X-ray photoelectron spectroscopy (XPS), and the outer phase confined the conductive magnetite phase within the insulating layers, enabling kinetic control of magnetite synthesis. As such, the reaction stopped at meta-stable magnetite with an excellent saturation magnetization (σs) of 86 emu g-1 and Tv > 120 K without affording the thermodynamically stable α-Fe2O3 as the major final product. The study also discusses the influence of parameters such as reaction temperature, initial grain size of FeCl2, the extent of hydration, and partial pressure of H2O.

18.
Am J Cardiol ; 205: 12-19, 2023 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-37579655

RESUMO

Recent studies suggested short-term mortality after transcatheter edge-to-edge repair (TEER) was comparable between men and women. However, the gender-specific prognostic difference in the long-term follow-up after TEER is still unknown. To evaluate the impact of gender on long-term mortality after TEER for functional mitral regurgitation (FMR) using multicenter registry data. We retrospectively analyzed 1,233 patients (male 60.3%) who underwent TEER for FMR at 24 centers. The impact of gender on all-cause death and hospitalization for heart failure (HF) after TEER was evaluated using multivariate regression analysis and propensity score (PS) matching methods. During the 2-year follow-up, 207 all-cause death and 263 hospitalizations for HF were observed after TEER for FMR. Men had a significantly higher incidence of all-cause death than women (18.6% vs 14.1%, log-rank p = 0.03). After adjustment by multivariate Cox regression and PS matching, the male gender was significantly associated with a higher incidence of all-cause mortality after TEER than the female gender (hazard ratio 2.11, 95% confidence interval 1.42 to 3.14 in multivariate Cox regression; hazard ratio 1.89, 95% confidence interval 1.03 to 3.48 in PS matching). The gender-specific prognostic difference was even more pronounced after 1-year of TEER. On the contrary, there was no gender-related difference in hospitalization for HF after TEER. In conclusion, women with FMR had a better prognosis after TEER than men, whereas this was not observed in hospitalization for HF. This result might indicate that women with FMR are more likely to benefit from TEER.


Assuntos
Insuficiência Cardíaca , Implante de Prótese de Valva Cardíaca , Insuficiência da Valva Mitral , Humanos , Feminino , Masculino , Insuficiência da Valva Mitral/cirurgia , Estudos Retrospectivos , Hospitalização , Análise Multivariada , Resultado do Tratamento
19.
Am J Cardiol ; 204: 130-139, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37541149

RESUMO

Electrocardiogram (ECG) left ventricular hypertrophy (LVH) is associated with the prognosis of patients with aortic stenosis. However, the impact of the presence or absence of ECG-LVH on the clinical outcomes after transcatheter aortic valve implantation (TAVI) is limited. This study aimed to assess the prognostic value of ECG-LVH among patients with aortic stenosis treated by TAVI. A total of 1,667 patients who underwent TAVI were prospectively enrolled into the OCEAN-TAVI (Optimized CathEter vAlvular iNtervention-Transcatheter Aortic Valve Implantation) registry. A total of 1,446 patients (mean age 84 years; 29.9% men) were analyzed. The Sokolow-Lyon index was used to determine the presence of ECG-LVH. LVH was also assessed using transthoracic echocardiography (TTE). We investigated the association between ECG-LVH and all-cause and cardiovascular mortality. This study identified ECG-LVH and TTE-LVH in 743 (51.5%) and 1,242 patients (86.0%), respectively. The Kaplan-Meier analysis revealed that all-cause mortality was significantly higher among patients without ECG-LVH than among those with ECG-LVH (log-rank p <0.001). In the multivariable analysis, the absence of ECG-LVH was independently associated with all-cause mortality (hazard ratio 1.98, 95% confidence interval 1.39 to 2.82, p <0.001), regardless of the presence or absence of TTE-LVH. Furthermore, the presence of TTE-LVH with the absence of ECG-LVH was observed in 575 patients (40%), which was associated with cardiovascular mortality (hazard ratio 2.84, 95% confidence interval 1.56 to 5.17, p <0.001). In conclusion, the absence of ECG-LVH was independently associated with an increased risk of all-cause mortality after TAVI. Risk stratification using both ECG-LVH and TTE-LVH is a useful predictor of adverse clinical outcomes after TAVI.


Assuntos
Estenose da Valva Aórtica , Substituição da Valva Aórtica Transcateter , Masculino , Humanos , Idoso de 80 Anos ou mais , Feminino , Substituição da Valva Aórtica Transcateter/efeitos adversos , Prognóstico , Hipertrofia Ventricular Esquerda/diagnóstico , Hipertrofia Ventricular Esquerda/epidemiologia , Hipertrofia Ventricular Esquerda/etiologia , Estenose da Valva Aórtica/diagnóstico , Estenose da Valva Aórtica/cirurgia , Estenose da Valva Aórtica/complicações , Sistema de Registros , Valva Aórtica/cirurgia , Resultado do Tratamento
20.
JACC Asia ; 3(2): 272-284, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37181391

RESUMO

Background: Limited data are available describing left atrial appendage closure (LAAC) and age-related outcomes in Asians. Objectives: This study summarizes the initial experience with LAAC in Japan and determines age-related clinical outcomes in patients with nonvalvular atrial fibrillation undergoing percutaneous LAAC. Methods: In an ongoing, prospective, investigator-initiated, multicenter, observational registry of patients undergoing LAAC in Japan, we analyzed short-term clinical outcomes in patients with nonvalvular atrial fibrillation who underwent LAAC. Patients were classified into younger, middle-aged, and elderly groups (≤70, 70 to 80, and >80 years of age, respectively) to determine age-related outcomes. Results: Patients (n = 548; mean age, 76.4 ± 8.1 years; male, 70.3%) who underwent LAAC at 19 Japanese centers between September 2019 and June 2021 were enrolled in the study, including 104, 271, and 173 patients in the younger, middle-aged, and elderly groups, respectively. Participants had a high-risk of bleeding and thromboembolism with a mean CHADS2 score of 3.1 ± 1.3, a mean CHA2DS2-VASc score of 4.7 ± 1.5, and a mean HAS-BLED score of 3.2 ± 1.0. Device success rates were 96.5% and anticoagulants discontinuation at the 45-day follow-up was achieved in 89.9%. In-hospital outcomes were not significantly different, but major bleeding events during the 45-day follow-up were significantly higher in the elderly group compared to the other groups (younger vs middle-aged vs elderly, 1.0% vs 3.7% vs 6.9%, respectively; P = 0.047) despite the same postoperative drug regimens. Conclusions: The initial Japanese experience with LAAC demonstrated safety and efficacy; however, perioperative bleeding events were more common in the elderly and postoperative drug regimens must be tailored (OCEAN-LAAC [Optimized Catheter Valvular Intervention-Left Atrial Appendage Closure] registry; UMIN000038498).

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