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1.
Nature ; 620(7974): 538-544, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37587296

RESUMO

Molecules present a versatile platform for quantum information science1,2 and are candidates for sensing and computation applications3,4. Robust spin-optical interfaces are key to harnessing the quantum resources of materials5. To date, carbon-based candidates have been non-luminescent6,7, which prevents optical readout via emission. Here we report organic molecules showing both efficient luminescence and near-unity generation yield of excited states with spin multiplicity S > 1. This was achieved by designing an energy resonance between emissive doublet and triplet levels, here on covalently coupled tris(2,4,6-trichlorophenyl) methyl-carbazole radicals and anthracene. We observed that the doublet photoexcitation delocalized onto the linked acene within a few picoseconds and subsequently evolved to a pure high-spin state (quartet for monoradical, quintet for biradical) of mixed radical-triplet character near 1.8 eV. These high-spin states are coherently addressable with microwaves even at 295 K, with optical readout enabled by reverse intersystem crossing to emissive states. Furthermore, for the biradical, on return to the ground state the previously uncorrelated radical spins either side of the anthracene shows strong spin correlation. Our approach simultaneously supports a high efficiency of initialization, spin manipulations and light-based readout at room temperature. The integration of luminescence and high-spin states creates an organic materials platform for emerging quantum technologies.

2.
Angew Chem Int Ed Engl ; : e202402052, 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38705856

RESUMO

Carbene-metal-amides (CMAs) are emerging delayed fluorescence materials for organic light-emitting diode (OLED) applications. CMAs possess fast, efficient emission owing to rapid forward and reverse intersystem crossing (ISC) rates. The resulting dynamic equilibrium between singlet and triplet spin manifolds distinguishes CMAs from most purely organic thermally activated delayed fluorescence emitters. However, direct experimental triplet characterization in CMAs is underutilized, limiting our detailed understanding of the ISC mechanism. In this work, we combine time-resolved spectroscopy with tuning of state energies through environmental polarity and metal substitution, focusing on the interplay between charge-transfer (3CT) and local exciton (3LE) triplets. Unlike previous photophysical work, we investigate evaporated host : guest films of CMAs and small-molecule hosts for increased device relevance. Transient absorption reveals an evolution in the triplet excited-state absorption (ESA) consistent with a change in orbital character between hosts with differing dielectric constants. Using quantum chemical calculations, we simulate ESAs of the lowest triplet states, highlighting the contribution of only 3CT and donor-moiety 3LE states to spectral features, with no strong evidence for a low-lying acceptor-centered 3LE. Thus, our work provides a blueprint for understanding the role of triplet excited states in CMAs which will enable further intelligent optimization of this promising class of materials.

3.
J Cardiovasc Electrophysiol ; 34(12): 2472-2483, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37767745

RESUMO

INTRODUCTION: Pulmonary vein isolation (PVI) is a pivotal part of ablative therapy for atrial fibrillation (AF). Currently, there are multiple techniques available to realize PVI, including: manual-guided cryoballoon (MAN-CB), manual-guided radiofrequency (MAN-RF), and robotic magnetic navigation-guided radiofrequency ablation (RMN-RF). There is a lack of large prospective trials comparing contemporary RMN-RF with the more conventional ablation techniques. This study prospectively compared three catheter ablation techniques as treatment of paroxysmal AF. METHODS: This multicenter, prospective study included patients with paroxysmal AF who underwent their first ablation procedure. Procedural parameters (including procedural efficiency), complication rates, and freedom of AF during 12-month follow-up, were compared between three study groups which were defined by the utilized ablation technique. RESULTS: A total of 221 patients were included in this study. Total procedure time was significantly shorter in MAN-CB (78 ± 21 min) compared to MAN-RF (115 ± 41 min; p < .001) and compared to RMN-RF (129 ± 32 min; p < .001), whereas it was comparable between the two radiofrequency (RF) groups (p = .062). A 3% complication rate was observed, which was comparable between all groups. At 12-month follow-up, AF recurrence was observed in 40 patients (19%) and was significantly lower in the robotic group (MAN-CB 19 [24%], MAN-RF 16 [23%], RMN-RF 5 [8%] AF recurrences, p = .045) (multivariate hazard ratio of RMN-RF on AF recurrence 0.32, 95% confidence interval: 0.12-0.87, p = .026). CONCLUSION: RMN-guided PVI results in high freedom of AF in patients with paroxysmal AF, when compared to cryoablation and manual RF ablation. Cryoablation remains the most time-efficient ablation technique, whereas RMN nowadays has comparable efficiency with manual RF ablation.


Assuntos
Fibrilação Atrial , Ablação por Cateter , Criocirurgia , Veias Pulmonares , Procedimentos Cirúrgicos Robóticos , Humanos , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/cirurgia , Ablação por Cateter/métodos , Criocirurgia/métodos , Fenômenos Magnéticos , Estudos Prospectivos , Veias Pulmonares/cirurgia , Recidiva , Resultado do Tratamento
4.
Heart Vessels ; 38(7): 881-888, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36695858

RESUMO

The optimal approach for prevention of cardiovascular events and reduction of bleeding in patients with acute coronary syndrome (ACS) and atrial fibrillation (AF) is still controversial. The aim of our study is to asses our single-center experience with concomitant left atrial appendage occlusion (LAAO) and percutaneous coronary intervention (PCI). 50 patients with ACS without ST elevation and history of AF were randomized after successful PCI to LAAO or conventional medical therapy. The primary endpoints were safety and length of hospitalization. The follow-up period was 30 days. The mean procedural times were 113 ± 23 min PCI + LAAO implantation and 39 ± 19 min of PCI only (p < 0.001), while mean fluoroscopy times were 18 ± 8 min and 12 ± 8 min (p < 0.001), respectively. No procedure-related complications were observed. There was no difference observed for length of hospitalization between two groups. LAAO in patients with ACS and AF undergoing PCI appears safe.


Assuntos
Síndrome Coronariana Aguda , Apêndice Atrial , Fibrilação Atrial , Intervenção Coronária Percutânea , Acidente Vascular Cerebral , Humanos , Fibrilação Atrial/complicações , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/cirurgia , Projetos Piloto , Síndrome Coronariana Aguda/complicações , Síndrome Coronariana Aguda/diagnóstico , Síndrome Coronariana Aguda/cirurgia , Apêndice Atrial/diagnóstico por imagem , Apêndice Atrial/cirurgia , Estudos de Viabilidade , Intervenção Coronária Percutânea/efeitos adversos , Resultado do Tratamento
5.
Molecules ; 28(11)2023 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-37298874

RESUMO

Gold-centered carbene-metal-amides (CMAs) containing cyclic (alkyl)(amino)carbenes (CAACs) are promising emitters for thermally activated delayed fluorescence (TADF). Aiming at the design and optimization of new TADF emitters, we report a density functional theory study of over 60 CMAs with various CAAC ligands, systematically evaluating computed parameters in relation to photoluminescence properties. The CMA structures were primarily selected based on experimental synthesis prospects. We demonstrate that TADF efficiency of the CMA materials originates from a compromise between oscillator strength coefficients and exchange energy (ΔEST). The latter is governed by the overlap of HOMO and LUMO orbitals, where HOMO is localized on the amide and LUMO over the Au-carbene bond. The S0 ground and excited T1 states of the CMAs adopt approximately coplanar geometry of carbene and amide ligands, but rotate perpendicular in the excited S1 states, resulting in degeneracy or near-degeneracy of S1 and T1, accompanied by a decrease in the S1-S0 oscillator strength from its maximum at coplanar geometries to near zero at rotated geometries. Based on the computations, promising new TADF emitters are proposed and synthesized. Bright CMA complex (Et2CAAC)Au(carbazolide) is obtained and fully characterized in order to demonstrate that excellent stability and high radiative rates up to 106 s-1 can be obtained for the gold-CMA complexes with small CAAC-carbene ligands.


Assuntos
Amidas , Ouro , Fluorescência , Ligantes
6.
Molecules ; 28(19)2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37836740

RESUMO

Copper-centered carbene-metal-halides (CMHs) with cyclic (alkyl)(amino) carbenes (CAACs) are bright phosphorescent emitters and key precursors in the synthesis of the highly promising class of the materials carbene-metal-amides (CMAs) operating via thermally activated delayed fluorescence (TADF). Aiming to reveal the molecular geometry for CMH phosphors in the absence of the intermolecular contacts, we report here the equilibrium molecular structure of the (CAAC)Cu(I)Cl (1) molecule in the gas-phase. We demonstrate that linear geometry around a copper atom shows no distortions in the ground state. The structure of complex 1 has been determined using the electron diffraction method, supported by quantum chemical calculations with RI-MP2/def2-QZVPP level of theory and compared with the crystal structure determined by X-ray diffraction analysis. Mean vibrational amplitudes, uij,h1, and anharmonic vibrational corrections (rij,e • rij,a) were calculated for experimental temperature T = 20 °C, using quadratic and cubic force constants, respectively. The quantum theory of atoms in molecules (QTAIM) and natural bond order (NBO) analysis of wave function at MN15/def2TZVP level of theory revealed two Cu…H, three H…H, and one three-center H…H…H bond paths with bond critical points. NBO analysis also revealed three-center, four-electron hyperbonds, (3c4e), [π(N-C) nπ(Cu) ↔ nπ(N) π(N-Cu)], or [N-C: Cu ↔ N: C-Cu] and nπ(Cu) → π(C-N)* hyperconjugation, that is the delocalization of the lone electron pair of Cu atom into the antibonding orbital of C-N bond.

7.
Beilstein J Org Chem ; 19: 1289-1298, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37701304

RESUMO

Organic thermally activated delayed fluorescence (TADF) materials have been widely investigated due to their impressive electronic properties and applied potential for the third generation of organic light-emitting diodes (OLED). We present organic TADF material (4BGIPN) based on the strained benzoguanidine donor and compare it with the benchmark carbazole-based material (4CzIPN). Extended π-conjugation in 4BGIPN material results in yellow-green luminescence at 512 nm with a fast radiative rate of 5.5 × 10-5 s-1 and a photoluminescence quantum yield of 46% in methylcyclohexane solution. Such a nitrogen-rich 4BGIPN material has a significantly stabilized highest occupied molecular orbital (HOMO) at -6.4 eV while the lowest unoccupied molecular orbital (LUMO) at -4.0 eV, indicating potential suitability for application as the electron transport layer or TADF class III emitter in OLEDs.

8.
Europace ; 23(3): 362-369, 2021 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-33330909

RESUMO

AIMS: Delay of progression from paroxysmal to persistent atrial fibrillation (AF) is an important measure of long-term success of AF treatment. However, published data on the impact of catheter ablation on AF progression are limited. This study evaluates whether radiofrequency (RF) catheter ablation delays the progression of AF compared with antiarrhythmic drug (AAD) treatment using current AF management guidelines. METHODS: This prospective, randomized, controlled, two-arm, open-label trial was conducted at 29 hospitals and medical centres across 13 countries. Patients were randomized 1 : 1 to RF ablation or AAD treatment. The primary endpoint was the rate of persistent AF/atrial tachycardia (AT) at 3 years. RESULTS: After early study termination following slow enrolment, 255 (79%) of the planned 322 patients were enrolled (RF ablation, n = 128, AAD, n = 127); 36% of patients in the RF ablation group and 41% in the AAD group completed 3 years of follow-up. For the primary endpoint, the Kaplan-Meier estimate of the rate of persistent AF/AT at 3 years was significantly lower with RF ablation [2.4% (95% confidence interval (CI), 0.6-9.4%)] than with AAD therapy [17.5% (95% CI, 10.7-27.9%); one-sided P = 0.0009]. Patients ≥65 years were ∼4 times more likely to progress to persistent AF/AT than patients <65 years, suggesting RF ablation can delay disease progression [hazard ratio: 3.87 (95% CI, 0.88-17.00); P = 0.0727]. Primary adverse events were reported for eight patients in the RF ablation group. CONCLUSIONS: Radiofrequency ablation is superior to guideline-directed AAD therapy in delaying the progression from paroxysmal to persistent AF.


Assuntos
Fibrilação Atrial , Ablação por Cateter , Antiarrítmicos/uso terapêutico , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/cirurgia , Ablação por Cateter/efeitos adversos , Humanos , Estudos Prospectivos , Recidiva , Resultado do Tratamento
9.
Pacing Clin Electrophysiol ; 44(2): 385-388, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32969523

RESUMO

Remote magnetic navigation (RMN) can be safely and effectively utilized in patients with difficult cardiac arrhythmias and complex anatomy. Interruption of the inferior vena cava (IVC) is a rare congenital abnormality that results in the inability to use conventional femoral access in patients that require interventional procedures. The present case demonstrates the feasibility of left atrial flutter ablation using RMN via jugular approach in a patient with interruption of IVC.


Assuntos
Flutter Atrial/cirurgia , Ablação por Cateter/métodos , Veias Jugulares , Veia Cava Inferior/anormalidades , Flutter Atrial/complicações , Procedimentos Cirúrgicos Cardíacos/métodos , Humanos , Campos Magnéticos , Masculino , Pessoa de Meia-Idade
10.
Nat Mater ; 18(6): 627-637, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31114073

RESUMO

Cells are transplanted to regenerate an organs' parenchyma, but how transplanted parenchymal cells induce stromal regeneration is elusive. Despite the common use of a decellularized matrix, little is known as to the pivotal signals that must be restored for tissue or organ regeneration. We report that Alx3, a developmentally important gene, orchestrated adult parenchymal and stromal regeneration by directly transactivating Wnt3a and vascular endothelial growth factor. In contrast to the modest parenchyma formed by native adult progenitors, Alx3-restored cells in decellularized scaffolds not only produced vascularized stroma that involved vascular endothelial growth factor signalling, but also parenchymal dentin via the Wnt/ß-catenin pathway. In an orthotopic large-animal model following parenchyma and stroma ablation, Wnt3a-recruited endogenous cells regenerated neurovascular stroma and differentiated into parenchymal odontoblast-like cells that extended the processes into newly formed dentin with a structure-mechanical equivalency to native dentin. Thus, the Alx3-Wnt3a axis enables postnatal progenitors with a modest innate regenerative capacity to regenerate adult tissues. Depleted signals in the decellularized matrix may be reinstated by a developmentally pivotal gene or corresponding protein.


Assuntos
Proteínas de Homeodomínio/metabolismo , Tecido Parenquimatoso/fisiologia , Dente/citologia , Dente/embriologia , Adolescente , Animais , Feminino , Proteínas de Homeodomínio/genética , Humanos , Incisivo/citologia , Incisivo/embriologia , Camundongos Endogâmicos , Dente Serotino/citologia , Técnicas de Cultura de Órgãos , Tecido Parenquimatoso/citologia , Gravidez , Regiões Promotoras Genéticas , Regeneração , Células Estromais/fisiologia , Suínos , Fator A de Crescimento do Endotélio Vascular/genética , Proteína Wnt3A/genética , Proteína Wnt3A/metabolismo
11.
Europace ; 22(4): 558-566, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-31821488

RESUMO

AIMS: The ESC EORP EHRA Atrial Fibrillation (AF) Ablation Long-Term registry was designed to assess management and outcomes of AF catheter ablation procedures in Europe. To investigate the current ablation approaches and their outcomes for patients with paroxymal AF (PAF) and non-PAF in Europe. METHODS AND RESULTS: Data from index ablations were collected in 27 European countries at 104 centres in a prospective fashion. Pre-procedural, procedural, and 1-year follow-up data were captured on a web-based electronic case record form. Data on the ablation procedure were available for 3446 patients. Of these, 2513 patients and 933 patients underwent pulmonary vein isolation (PVI) or PVI plus (PVIplus) additional ablation, respectively. The ablation strategy was limited to PVI in 81% and 56% of patients in the PAF and non-PAF group, respectively (P < 0.001). In the non-PAF group, left atrial linear ablation and ablation of complex fragmented atrial electrograms were more commonly performed. Arrhythmias recurrence after PVI was 29% and 39% in the PAF and non-PAF group, respectively (P < 0.001) and 42% after PVIplus in both groups. Atrial fibrillation related hospital admissions were more common in the PVIplus group (20% vs. 14%). A very low procedural complication rate was observed. No relevant differences were observed with regard to repeat ablation (PVI 9% and PVIplus 11%). CONCLUSION: In patients with PAF and non-PAF, the ablation strategies of PVI and PVIplus led to similar arrhythmia-free survival rates after 1 year. A considerable hospital readmission rate was noted.


Assuntos
Fibrilação Atrial , Ablação por Cateter , Veias Pulmonares , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/cirurgia , Europa (Continente) , Humanos , Estudos Prospectivos , Veias Pulmonares/cirurgia , Recidiva , Sistema de Registros , Resultado do Tratamento
12.
Mar Drugs ; 18(8)2020 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-32748868

RESUMO

Several experimental studies have recently demonstrated that temporary autonomic block using botulinum toxin (BoNT/A1) might be a novel option for the treatment of atrial fibrillation. However, the assessment of antiarrhythmic properties of BoNT has so far been limited, relying exclusively on vagal stimulation and rapid atrial pacing models. The present study examined the antiarrhythmic effect of specially formulated BoNT/A1-chitosan nanoparticles (BTN) in calcium chloride-, barium chloride- and electrically induced arrhythmia rat models. BTN enhanced the effect of BoNT/A1. Subepicardial injection of BTN resulted in a significant antiarrhythmic effect in investigated rat models. BTN formulation antagonizes arrhythmia induced by the activation of Ca, K and Na channels.


Assuntos
Antiarrítmicos/farmacologia , Arritmias Cardíacas/prevenção & controle , Toxinas Botulínicas Tipo A/farmacologia , Sistema de Condução Cardíaco/efeitos dos fármacos , Frequência Cardíaca/efeitos dos fármacos , Nanopartículas , Potenciais de Ação/efeitos dos fármacos , Animais , Antiarrítmicos/química , Arritmias Cardíacas/metabolismo , Arritmias Cardíacas/fisiopatologia , Toxinas Botulínicas Tipo A/química , Canais de Cálcio/efeitos dos fármacos , Canais de Cálcio/metabolismo , Quitosana/química , Modelos Animais de Doenças , Composição de Medicamentos , Sistema de Condução Cardíaco/metabolismo , Sistema de Condução Cardíaco/fisiopatologia , Masculino , Canais de Potássio/efeitos dos fármacos , Canais de Potássio/metabolismo , Ratos Wistar , Canais de Sódio/efeitos dos fármacos , Canais de Sódio/metabolismo
13.
JAMA ; 323(3): 248-255, 2020 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-31961420

RESUMO

Importance: Renal denervation can reduce cardiac sympathetic activity that may result in an antiarrhythmic effect on atrial fibrillation. Objective: To determine whether renal denervation when added to pulmonary vein isolation enhances long-term antiarrhythmic efficacy. Design, Setting, and Participants: The Evaluate Renal Denervation in Addition to Catheter Ablation to Eliminate Atrial Fibrillation (ERADICATE-AF) trial was an investigator-initiated, multicenter, single-blind, randomized clinical trial conducted at 5 referral centers for catheter ablation of atrial fibrillation in the Russian Federation, Poland, and Germany. A total of 302 patients with hypertension despite taking at least 1 antihypertensive medication, paroxysmal atrial fibrillation, and plans for ablation were enrolled from April 2013 to March 2018. Follow-up concluded in March 2019. Interventions: Patients were randomized to either pulmonary vein isolation alone (n = 148) or pulmonary vein isolation plus renal denervation (n = 154). Complete pulmonary vein isolation to v an end point of elimination of all pulmonary vein potentials; renal denervation using an irrigated-tip ablation catheter delivering radiofrequency energy to discrete sites in a spiral pattern from distal to proximal in both renal arteries. Main Outcomes and Measures: The primary end point was freedom from atrial fibrillation, atrial flutter, or atrial tachycardia at 12 months. Secondary end points included procedural complications within 30 days and blood pressure control at 6 and 12 months. Results: Of the 302 randomized patients (median age, 60 years [interquartile range, 55-65 years]; 182 men [60.3%]), 283 (93.7%) completed the trial. All successfully underwent their assigned procedures. Freedom from atrial fibrillation, flutter, or tachycardia at 12 months was observed in 84 of 148 (56.5%) of those undergoing pulmonary vein isolation alone and in 111 of 154 (72.1%) of those undergoing pulmonary vein isolation plus renal denervation (hazard ratio, 0.57; 95% CI, 0.38 to 0.85; P = .006). Of 5 prespecified secondary end points, 4 are reported and 3 differed between groups. Mean systolic blood pressure from baseline to 12 months decreased from 151 mm Hg to 147 mm Hg in the isolation-only group and from 150 mm Hg to 135 mm Hg in the renal denervation group (between-group difference, -13 mm Hg; 95% CI, -15 to -11 mm Hg; P < .001). Procedural complications occurred in 7 patients (4.7%) in the isolation-only group and 7 (4.5%) of the renal denervation group. Conclusions and Relevance: Among patients with paroxysmal atrial fibrillation and hypertension, renal denervation added to catheter ablation, compared with catheter ablation alone, significantly increased the likelihood of freedom from atrial fibrillation at 12 months. The lack of a formal sham-control renal denervation procedure should be considered in interpreting the results of this trial. Trial Registration: ClinicalTrials.gov Identifier: NCT01873352.


Assuntos
Fibrilação Atrial/cirurgia , Ablação por Cateter , Hipertensão/cirurgia , Rim/inervação , Veias Pulmonares/cirurgia , Simpatectomia , Idoso , Anti-Hipertensivos/uso terapêutico , Fibrilação Atrial/complicações , Fibrilação Atrial/prevenção & controle , Terapia Combinada , Resistência a Medicamentos , Feminino , Humanos , Hipertensão/complicações , Hipertensão/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Prevenção Secundária , Método Simples-Cego
14.
Respir Res ; 20(1): 116, 2019 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-31182072

RESUMO

BACKGROUND: Expression of the Receptor for Advanced Glycation Endproducts (RAGE) initiates pro-inflammatory pathways resulting in lung destruction. We hypothesized that RAGE directed imaging demonstrates increased lung uptake in smoke-exposure. METHODS: After exposure to room air or to cigarette smoke for 4-weeks or 16-weeks, rabbits were injected with 99mTc-anti-RAGE F(ab')2 and underwent Single-Photon Emission Computed Tomography/Computed Tomography (SPECT/CT) imaging. Lung radiotracer uptake was calculated as percent injected dose (%ID). Lungs were dissected for gamma well counting and histological analysis. RESULTS: 99mTc-anti-RAGE F(ab')2 SPECT/CT imaging demonstrated increased lung expression of RAGE with smoke exposure compared to room air control at 4-weeks: Room air right (R) 0.75 ± 0.38%ID, left (L) 0.62 ± 0.32%ID vs. Smoke exposed R 0.17 ± 0.03, L 0.17 ± 0.02%ID (p = 0.02 and 0.028, respectively). By 16-weeks of smoke exposure, the uptake decreased to 0.19 ± 0.05%ID R and 0.17 ± 0.05%ID L, significantly lower than 4-week imaging (p = 0.0076 and 0.0129 respectively). Staining for RAGE confirmed SPECT results, with the RAGE ligand HMGB1 upregulated in the macrophages of 4-week smoke-exposed rabbits. CONCLUSIONS: RAGE-directed imaging identified pulmonary RAGE expression acutely in vivo in an animal model of emphysema early after smoke exposure, with diminution over time. These studies document the extent and time course of RAGE expression under smoke exposure conditions and could be utilized for disease monitoring and examining response to future RAGE-targeted therapies.


Assuntos
Modelos Animais de Doenças , Pulmão/diagnóstico por imagem , Pulmão/metabolismo , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Tomografia Computadorizada com Tomografia Computadorizada de Emissão de Fóton Único/métodos , Fumar Tabaco/metabolismo , Animais , Feminino , Coelhos , Fumar , Fumar Tabaco/patologia
15.
Eur Heart J ; 39(37): 3464-3471, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-30113633

RESUMO

Aims: Hypertension (HTN) is a well-known contributor to cardiovascular disease, including heart failure (HF) and coronary artery disease, and is the leading risk factor for premature death world-wide. A J- or U-shaped relationship has been suggested between blood pressure (BP) and clinical outcomes in different studies. However, there is little information about the significance of BP on the outcomes of patients with coronary artery disease and left ventricular dysfunction. This study aimed to determine the relationship between BP and mortality outcomes in patients with ischaemic cardiomyopathy. Methods and results: The influence of BP during a median follow-up of 9.8 years was studied in a total of 1212 patients with ejection fraction ≤35% and coronary disease amenable to coronary artery bypass grafting (CABG) who were randomized to CABG or medical therapy alone (MED) in the STICH (Surgical Treatment for Ischaemic Heart Failure) trial. Landmark analyses were performed starting at 1, 2, 3, 4, and 5 years after randomization, in which previous systolic BP values were averaged and related to subsequent mortality through the end of follow-up with a median of 9.8 years. Neither a previous history of HTN nor baseline BP had any significant influence on long-term mortality outcomes, nor did they have a significant interaction with MED or CABG treatment. The landmark analyses showed a progressive U-shaped relationship that became strongest at 5 years (χ2 and P-values: 7.08, P = 0.069; 8.72, P = 0.033; 9.86; P = 0.020; 8.31, P = 0.040; 14.52, P = 0.002; at 1, 2, 3, 4, and 5-year landmark analyses, respectively). The relationship between diastolic BP (DBP) and outcomes was similar. The most favourable outcomes were observed in the SBP range 120-130, and DBP 75-85 mmHg, whereas lower and higher BP were associated with worse outcomes. There were no differences in BP-lowering medications between groups. Conclusion: A strong U-shaped relationship between BP and mortality outcomes was evident in ischaemic HF patients. The results imply that the optimal SBP might be in the range 120-130 mmHg after intervention, and possibly be subject to pharmacologic action regarding high BP. Further, low BP was a marker of poor outcomes that might require other interactions and treatment strategies. Clinical Trial Registration: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00023595.


Assuntos
Pressão Sanguínea/fisiologia , Ponte de Artéria Coronária/mortalidade , Doença da Artéria Coronariana , Insuficiência Cardíaca , Hipertensão , Isquemia Miocárdica , Idoso , Doença da Artéria Coronariana/complicações , Doença da Artéria Coronariana/epidemiologia , Doença da Artéria Coronariana/mortalidade , Feminino , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/epidemiologia , Insuficiência Cardíaca/mortalidade , Humanos , Hipertensão/complicações , Hipertensão/epidemiologia , Hipertensão/mortalidade , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/complicações , Isquemia Miocárdica/epidemiologia , Isquemia Miocárdica/mortalidade , Isquemia Miocárdica/cirurgia
16.
JAMA ; 321(13): 1261-1274, 2019 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-30874766

RESUMO

Importance: Catheter ablation is effective in restoring sinus rhythm in atrial fibrillation (AF), but its effects on long-term mortality and stroke risk are uncertain. Objective: To determine whether catheter ablation is more effective than conventional medical therapy for improving outcomes in AF. Design, Setting, and Participants: The Catheter Ablation vs Antiarrhythmic Drug Therapy for Atrial Fibrillation trial is an investigator-initiated, open-label, multicenter, randomized trial involving 126 centers in 10 countries. A total of 2204 symptomatic patients with AF aged 65 years and older or younger than 65 years with 1 or more risk factors for stroke were enrolled from November 2009 to April 2016, with follow-up through December 31, 2017. Interventions: The catheter ablation group (n = 1108) underwent pulmonary vein isolation, with additional ablative procedures at the discretion of site investigators. The drug therapy group (n = 1096) received standard rhythm and/or rate control drugs guided by contemporaneous guidelines. Main Outcomes and Measures: The primary end point was a composite of death, disabling stroke, serious bleeding, or cardiac arrest. Among 13 prespecified secondary end points, 3 are included in this report: all-cause mortality; total mortality or cardiovascular hospitalization; and AF recurrence. Results: Of the 2204 patients randomized (median age, 68 years; 37.2% female; 42.9% had paroxysmal AF and 57.1% had persistent AF), 89.3% completed the trial. Of the patients assigned to catheter ablation, 1006 (90.8%) underwent the procedure. Of the patients assigned to drug therapy, 301 (27.5%) ultimately received catheter ablation. In the intention-to-treat analysis, over a median follow-up of 48.5 months, the primary end point occurred in 8.0% (n = 89) of patients in the ablation group vs 9.2% (n = 101) of patients in the drug therapy group (hazard ratio [HR], 0.86 [95% CI, 0.65-1.15]; P = .30). Among the secondary end points, outcomes in the ablation group vs the drug therapy group, respectively, were 5.2% vs 6.1% for all-cause mortality (HR, 0.85 [95% CI, 0.60-1.21]; P = .38), 51.7% vs 58.1% for death or cardiovascular hospitalization (HR, 0.83 [95% CI, 0.74-0.93]; P = .001), and 49.9% vs 69.5% for AF recurrence (HR, 0.52 [95% CI, 0.45-0.60]; P < .001). Conclusions and Relevance: Among patients with AF, the strategy of catheter ablation, compared with medical therapy, did not significantly reduce the primary composite end point of death, disabling stroke, serious bleeding, or cardiac arrest. However, the estimated treatment effect of catheter ablation was affected by lower-than-expected event rates and treatment crossovers, which should be considered in interpreting the results of the trial. Trial Registration: ClinicalTrials.gov Identifier: NCT00911508.


Assuntos
Antiarrítmicos/uso terapêutico , Fibrilação Atrial/tratamento farmacológico , Fibrilação Atrial/cirurgia , Ablação por Cateter , Parada Cardíaca/prevenção & controle , Hemorragia/prevenção & controle , Acidente Vascular Cerebral/prevenção & controle , Idoso , Antiarrítmicos/efeitos adversos , Fibrilação Atrial/complicações , Fibrilação Atrial/mortalidade , Ablação por Cateter/efeitos adversos , Feminino , Parada Cardíaca/etiologia , Hemorragia/etiologia , Hospitalização/estatística & dados numéricos , Humanos , Análise de Intenção de Tratamento , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Recidiva , Sistema de Registros , Fatores de Risco , Acidente Vascular Cerebral/etiologia
17.
Circulation ; 135(12): 1136-1144, 2017 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-28154006

RESUMO

BACKGROUND: The risk of sudden cardiac death (SCD) in patients with heart failure after coronary artery bypass graft surgery (CABG) has not been examined in a contemporary clinical trial of surgical revascularization. This analysis describes the incidence, timing, and clinical predictors of SCD after CABG. METHODS: Patients enrolled in the STICH trial (Surgical Treatment of Ischemic Heart Failure) who underwent CABG with or without surgical ventricular reconstruction were included. We excluded patients with prior implantable cardioverter-defibrillator and those randomized only to medical therapy. The primary outcome was SCD as adjudicated by a blinded committee. A Cox model was used to examine and identify predictors of SCD. The Fine and Gray method was used to estimate the incidence of SCD accounting for the competing risk of other deaths. RESULTS: Over a median follow-up of 46 months, 113 of 1411 patients who received CABG without (n = 934) or with (n = 477) surgical ventricular reconstruction had SCD; 311 died of other causes. The mean left ventricular ejection fraction at enrollment was 28±9%. The 5-year cumulative incidence of SCD was 8.5%. Patients who had SCD and those who did not die were younger and had fewer comorbid conditions than did those who died of causes other than SCD. In the first 30 days after CABG, SCD (n=5) accounted for 7% of all deaths. The numerically greatest monthly rate of SCD was in the 31- to 90-day time period. In a multivariable analysis including baseline demographics, risk factors, coronary anatomy, and left ventricular function, end-systolic volume index and B-type natriuretic peptide were most strongly associated with SCD. CONCLUSIONS: The monthly risk of SCD shortly after CABG among patients with a low left ventricular ejection fraction is highest between the first and third months, suggesting that risk stratification for SCD should occur early in the postoperative period, particularly in patients with increased preoperative end-systolic volume index or B-type natriuretic peptide. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT0002359.


Assuntos
Ponte de Artéria Coronária/efeitos adversos , Morte Súbita Cardíaca/etiologia , Insuficiência Cardíaca/cirurgia , Idoso , Fibrilação Atrial/patologia , Fibrilação Atrial/prevenção & controle , Morte Súbita Cardíaca/epidemiologia , Feminino , Seguimentos , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Incidência , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Peptídeo Natriurético Encefálico/análise , Período Pós-Operatório , Modelos de Riscos Proporcionais , Receptores do Fator de Necrose Tumoral/análise , Fatores de Risco , Volume Sistólico , Função Ventricular Esquerda
18.
J Cardiovasc Electrophysiol ; 29(6): 872-878, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29570894

RESUMO

INTRODUCTION: The PREVENT AF I study demonstrated that prophylactic pulmonary vein isolation (PVI) in patients with pure typical atrial flutter (AFL) resulted in substantial reduction of new-onset atrial fibrillation (AF) during 1-year follow-up as assessed by continuous implantable cardiac monitor (ICM). The objective of this study was to assess 3-year outcomes. METHODS AND RESULTS: Fifty patients with documented AFL were randomized to either cavotricuspid isthmus (CTI) ablation alone (n = 25) or CTI with concomitant PVI (n = 25). The primary endpoint of the study was the occurrence of any atrial tachyarrhythmia with the monthly burden exceeding 0.5% on the ICM. At the end of 3 years, freedom from any atrial tachyarrhythmia was 48% (95% confidence interval [CI]: 32-72%) in the CTI plus PVI group as compared to 20% (95% CI: 9-44%) in the CTI-only group (P = 0.01). Freedom from redo procedures was also higher: 92% (95% CI: 82-100%) versus 68% (95% CI: 52-89%), respectively (P = 0.027). The 3-year AF burden favored the combined ablation group: 6.2% versus 16.8% (P = 0.03). In the CTI-only group, 12 (48%) patients were hospitalized compared to 4 (16%) in the PVI + CTI group (P = 0.03). Two patients in the CTI-only group developed stroke with no serious adverse events in the PVI + CTI group. CONCLUSION: Prophylactic PVI in patients with only typical AFL resulted in a significant reduction of new-onset AF and burden during long-term follow-up as assessed by ICM, with consequent reduction in hospitalizations and need to perform repeat ablation for AF.


Assuntos
Fibrilação Atrial/prevenção & controle , Flutter Atrial/cirurgia , Ablação por Cateter , Veias Pulmonares/cirurgia , Valva Tricúspide/cirurgia , Veia Cava Superior/cirurgia , Potenciais de Ação , Idoso , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/etiologia , Fibrilação Atrial/fisiopatologia , Flutter Atrial/diagnóstico , Flutter Atrial/fisiopatologia , Ablação por Cateter/efeitos adversos , Feminino , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Readmissão do Paciente , Projetos Piloto , Intervalo Livre de Progressão , Estudos Prospectivos , Veias Pulmonares/fisiopatologia , Recidiva , Reoperação , Fatores de Risco , Fatores de Tempo , Valva Tricúspide/fisiopatologia , Veia Cava Superior/fisiopatologia
19.
J Interv Cardiol ; 31(4): 442-449, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29651802

RESUMO

OBJECTIVE: We aimed to assess early neointimal healing by optical coherence tomography (OCT) 3 months after implantation of the ultrathin Orsiro® sirolimus-eluting stent with biodegradable polymer. BACKGROUND: New generations of drug-eluting stents with biodegradable polymer have been developed to avoid the continued vascular irritation of durable polymers. METHODS: In this prospective, open-label study, 34 patients received an Orsiro® sirolimus-eluting stent with biodegradable polymer. In a subgroup of patients (n = 15), the intervention was performed under OCT guidance. All patients underwent OCT-examination at three months. The primary endpoint was 3-month neointimal healing (NIH) score, calculated by weighing the presence of filling defects, malapposed and uncovered struts. Secondary endpoint was maturity of tissue coverage at 3 months. RESULTS: At 3 months, NIH score was 13.7 (5.4-22), covered struts per lesion were 90% (84-97%), malapposed struts were 2.7% (0.8-5.4%) and rate of mature tissue coverage was 47% (42-53%). No target lesion failure occurred up to 12 months. Patients with OCT-guided stent implantation demonstrated a trend toward earlier stent healing as demonstrated by superior NIH scores (angio guided: 17.6% [8.8-26.4]; OCT-guided: 9.8% [4.0-15.5]; mean difference -8, [95%CI: -18.7-2.9], P = 0.123). This group had significantly more covered struts per lesion (angio-guided: 86% [82-90]; 95% [92-99]; mean difference 9% [95%CI: 3-15], P = 0.001). CONCLUSION: The Orsiro® sirolimus-eluting stent with biodegradable polymer shows early vascular healing with a high rate of strut coverage at 3-month follow-up. OCT guided stent implantation had a positive impact on early vascular healing.


Assuntos
Plásticos Biodegradáveis/farmacologia , Stents Farmacológicos , Neointima/diagnóstico por imagem , Sirolimo/farmacologia , Tomografia de Coerência Óptica/métodos , Idoso , Feminino , Humanos , Imunossupressores/farmacologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento , Cicatrização/efeitos dos fármacos
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