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1.
Am Heart J ; 264: 123-132, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37279840

RESUMO

BACKGROUND: Percutaneous left atrial appendage (LAA) closure (LAAC) was developed as a nonpharmacologic alternative to oral anticoagulants (OACs) in patients with atrial fibrillation (AF) who are at an increased risk for stroke or systemic embolism. The Watchman device permanently seals off the LAA to prevent thrombi from escaping into the circulation. Previous randomized trials have established the safety and efficacy of LAAC compared to warfarin. However, direct OACs (DOACs) have become the preferred pharmacologic strategy for stroke prevention in patients with AF, and there is limited data comparing Watchman FLX to DOACs in a broad AF patient population. CHAMPION-AF is designed to prospectively determine whether LAAC with Watchman FLX is a reasonable first-line alternative to DOACs in patients with AF who are indicated for OAC therapy. STUDY DESIGN: A total of 3,000 patients with a CHA2DS2-VASc score ≥2 (men) or ≥3 (women) were randomized to Watchman FLX or DOAC in a 1:1 allocation at 142 global clinical sites. Patients in the device arm were to be treated with DOAC and aspirin, DOAC alone, or DAPT for at least 3 months postimplant followed by aspirin or P2Y12 inhibitor for 1-year. Control patients were required to take an approved DOAC for the duration of the trial. Clinical follow-up visits are scheduled at 3- and 12-months, and then annually through 5 years; LAA imaging is required at 4 months in the device group. Two primary end points will be evaluated at 3 years: (1) composite of stroke (ischemic/hemorrhagic), cardiovascular death, and systemic embolism compared for noninferiority, and (2) nonprocedural bleeding (International Society on Thrombosis and Haemostasis [ISTH] major and clinically relevant nonmajor bleeding) tested for superiority in the device arm against DOACs. The third primary noninferiority end point is the composite of ischemic stroke and systemic embolism at 5 years. Secondary end points include 3- and 5-year rates of (1) ISTH-defined major bleeding and (2) the composite of cardiovascular death, all stroke, systemic embolism, and nonprocedural ISTH bleeding. CONCLUSIONS: This study will prospectively evaluate whether LAAC with the Watchman FLX device is a reasonable alternative to DOACs in patients with AF. CLINICAL TRIAL REGISTRATION: NCT04394546.


Assuntos
Apêndice Atrial , Fibrilação Atrial , Embolia , Acidente Vascular Cerebral , Masculino , Humanos , Feminino , Fibrilação Atrial/complicações , Fibrilação Atrial/tratamento farmacológico , Resultado do Tratamento , Seguimentos , Apêndice Atrial/cirurgia , Anticoagulantes/uso terapêutico , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/prevenção & controle , Acidente Vascular Cerebral/epidemiologia , Hemorragia/induzido quimicamente , Hemorragia/complicações , Aspirina/uso terapêutico , Embolia/prevenção & controle
2.
Europace ; 25(3): 914-921, 2023 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-36734247

RESUMO

AIMS: The FLXibility Post-Approval Study collected data on unselected patients implanted with a WATCHMAN FLX in a commercial clinical setting. METHODS AND RESULTS: Patients were implanted with a WATCHMAN FLX per local standard of care, with a subsequent first follow-up visit from 45 to 120 days post-implant and a final follow-up at 1-year post-procedure. A Clinical Event Committee adjudicated all major adverse events and TEE/CT imaging results were adjudicated by a core laboratory. Among 300 patients enrolled at 17 centres in Europe, the mean age was 74.6 ± 8.0 years, mean CHA2DS2-VASc score was 4.3 ± 1.6, and 62.1% were male. The device was successfully implanted in 99.0% (297/300) of patients. The post-implant medication regimen was DAPT for 87.3% (262/300). At first follow-up, core-lab adjudicated complete seal was 88.2% (149/169), 9.5% (16/169) had leak <3 mm, 2.4 (4/169) had leak ≥3 mm to ≤5 mm, and 0% had >5 mm leak. At 1 year, 93.3% (280/300) had final follow-up; 60.5% of patients were on a single antiplatelet medication, 21.4% were on DAPT, 5.6% were on direct oral anticoagulation, and 12.1% were not taking any antiplatelet/anticoagulation medication. Adverse event rates through 1 year were: all-cause death 10.8% (32/295); CV/unexplained death 5.1% (15/295); disabling and non-disabling stroke each 1.0% (3/295, all non-fatal); pericardial effusion requiring surgery or pericardiocentesis 1.0% (3/295); and device-related thrombus 2.4% (7/295). CONCLUSION: The WATCHMAN FLX device had excellent procedural success rates, high LAA seal rates, and low rates of thromboembolic events in everyday clinical practice.


Assuntos
Apêndice Atrial , Fibrilação Atrial , Acidente Vascular Cerebral , Humanos , Masculino , Idoso , Idoso de 80 Anos ou mais , Feminino , Inibidores da Agregação Plaquetária/uso terapêutico , Apêndice Atrial/diagnóstico por imagem , Apêndice Atrial/cirurgia , Resultado do Tratamento , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/cirurgia , Fibrilação Atrial/complicações , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/prevenção & controle , Anticoagulantes/efeitos adversos , Cateterismo Cardíaco/efeitos adversos , Ecocardiografia Transesofagiana
3.
J Interv Cardiol ; 2022: 9138403, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35832535

RESUMO

Objectives: The PROGRESS PVL registry evaluated transcatheter aortic valve implantation (TAVI) in patients treated with ACURATE neo, a supra-annular self-expanding bioprosthetic aortic valve. Background: While clinical outcomes with TAVI are comparable with those achieved with surgery, residual aortic regurgitation (AR) and paravalvular leak (PVL) are common complications. The ACURATE neo valve has a pericardial sealing skirt designed to minimize PVL. Methods: The primary endpoint was the rate of total AR over time, as assessed by a core echocardiographic laboratory. The study enrolled 500 patients (mean age: 81.8 ± 5.1 years; 61% female; mean baseline STS score: 6.0 ± 4.5%) from 22 centers in Europe and Canada; 498 patients were treated with ACURATE neo. Results: The rate of ≥ moderate AR was 4.6% at discharge and 3.1% at 12 months; the rate of ≥ moderate PVL was 4.6% at discharge and 2.6% at 12 months. Paired analyses showed significant improvement in overall PVL between discharge and 12 months (P < 0.001); 64.6% of patients had no change in PVL grade, 24.9% improved, and 10.5% worsened. Patients also exhibited significant improvement in transvalvular gradient (P < 0.001) and effective orifice area (P=0.01). The mortality rate was 2.2% at 30 days and 11.3% at 12 months. The permanent pacemaker implantation (PPI) rate was 10.2% at 30 days and 12.2% at 12 months. Conclusions: Results from PROGRESS PVL support the sustained safety and performance of TAVI with the ACURATE neo valve, showing excellent valve hemodynamics, good clinical outcomes, and significant interindividual improvement in PVL from discharge to 12-month follow-up.


Assuntos
Insuficiência da Valva Aórtica , Estenose da Valva Aórtica , Próteses Valvulares Cardíacas , Substituição da Valva Aórtica Transcateter , Idoso , Idoso de 80 Anos ou mais , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/cirurgia , Insuficiência da Valva Aórtica/etiologia , Insuficiência da Valva Aórtica/cirurgia , Estenose da Valva Aórtica/cirurgia , Feminino , Próteses Valvulares Cardíacas/efeitos adversos , Humanos , Masculino , Desenho de Prótese , Sistema de Registros , Substituição da Valva Aórtica Transcateter/métodos , Resultado do Tratamento
4.
Neuroimage ; 238: 118237, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34091035

RESUMO

Magnetic resonance fingerprinting (MRF) is a quantitative MRI (qMRI) framework that provides simultaneous estimates of multiple relaxation parameters as well as metrics of field inhomogeneity in a single acquisition. However, current challenges exist in the forms of (1) scan time; (2) need for custom image reconstruction; (3) large dictionary sizes; (4) long dictionary-matching time. This study aims to introduce a novel streamlined magnetic-resonance fingerprinting (sMRF) framework based on a single-shot echo-planar imaging (EPI) sequence to simultaneously estimate tissue T1, T2, and T2* with integrated B1+ correction. Encouraged by recent work on EPI-based MRF, we developed a method that combines spin-echo EPI with gradient-echo EPI to achieve T2 in addition to T1 and T2* quantification. To this design, we add simultaneous multi-slice (SMS) acceleration to enable full-brain coverage in a few minutes. Moreover, in the parameter-estimation step, we use deep learning to train a deep neural network (DNN) to accelerate the estimation process by orders of magnitude. Notably, due to the high image quality of the EPI scans, the training process can rely simply on Bloch-simulated data. The DNN also removes the need for storing large dictionaries. Phantom scans along with in-vivo multi-slice scans from seven healthy volunteers were acquired with resolutions of 1.1×1.1×3 mm3 and 1.7×1.7×3 mm3, and the results were validated against ground truth measurements. Excellent correspondence was found between our T1, T2, and T2* estimates and results obtained from standard approaches. In the phantom scan, a strong linear relationship (R = 1-1.04, R2>0.96) was found for all parameter estimates, with a particularly high agreement for T2 estimation (R2>0.99). Similar findings are reported for the in-vivo human data for all of our parameter estimates. Incorporation of DNN results in a reduction of parameter estimation time on the order of 1000 x and a reduction in storage requirements on the order of 2500 x while achieving highly similar results as conventional dictionary matching (%differences of 7.4 ± 0.4%, 3.6 ± 0.3% and 6.0 ± 0.4% error in T1, T2, and T2* estimation). Thus, sMRF has the potential to be the method of choice for future MRF studies by providing ease of implementation, fast whole-brain coverage, and ultra-fast T1/T2/T2* estimation.


Assuntos
Aprendizado Profundo , Imagem Ecoplanar/métodos , Neuroimagem/métodos , Humanos , Processamento de Imagem Assistida por Computador , Método de Monte Carlo , Redes Neurais de Computação , Imagens de Fantasmas
5.
Catheter Cardiovasc Interv ; 93(3): 398-403, 2019 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-30341836

RESUMO

OBJECTIVES: The goal of this analysis was to evaluate the final 5-year safety and effectiveness of the PROMUS Element platinum-chromium everolimus-eluting stent in unselected patients treated in routine clinical practice. BACKGROUND: The prospective, open-label PROMUS Element™ European Post-Approval Surveillance Study (PE-PROVE) enrolled 1,010 "real-world" patients who received the PROMUS Element stent. Adverse event rates were low at 1-year, and the incidence of stent thrombosis was 0.6%. METHODS: The primary endpoint was target vessel failure (TVF; overall and PE stent-related), a composite of cardiac death, myocardial infarction (MI) related to the target vessel, or target vessel revascularization (TVR) at 1-year post-implantation. Five-year clinical outcomes were evaluated in overall as well as high-risk patient subgroups. RESULTS: The overall 5-year TVF rate was 14.9%, with 7.0% being related to the study stent. Cardiac death, MI and TVR related to the study stent occurred in 0.5%, 3.2%, and 5.7%, respectively. Stent thrombosis through 5-year follow-up was 1.0%. The rates of overall and study stent related TVF were numerically higher in patients with medically treated diabetes, long lesions (≥28 mm), and small diameter vessels (≤2.5 mm) compared to the overall study population. Additionally, favorable stent thrombosis rates through 5 years were reported for the PROMUS Element stent in these high-risk subgroups. CONCLUSIONS: The final 5-year data from the PE-PROVE study demonstrate favorable outcomes and low rates of adverse events with the PE stent when used in "real-world" patients with coronary artery disease.


Assuntos
Fármacos Cardiovasculares/administração & dosagem , Cromo , Doença da Artéria Coronariana/terapia , Stents Farmacológicos , Everolimo/administração & dosagem , Intervenção Coronária Percutânea/instrumentação , Platina , Fármacos Cardiovasculares/efeitos adversos , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/mortalidade , Trombose Coronária/mortalidade , Europa (Continente) , Everolimo/efeitos adversos , Feminino , Humanos , Masculino , Infarto do Miocárdio/mortalidade , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/mortalidade , Estudos Prospectivos , Desenho de Prótese , Sistema de Registros , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
6.
Am Heart J ; 205: 110-117, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30218844

RESUMO

BACKGROUND: While extended dual antiplatelet therapy (DAPT) with aspirin and a platelet (P2Y12) inhibitor after percutaneous coronary intervention (PCI) reduces the risk of stent thrombosis (ST) and myocardial infarction (MI), it also increases bleeding. Newer generation drug-eluting stents with bioabsorbable polymer coatings may reduce thrombotic events and allow abbreviated DAPT in selected patients. The EVOLVE Short DAPT study is designed to evaluate the safety of 3-month DAPT in high bleeding risk subjects treated with the SYNERGY bioabsorbable polymer everolimus-eluting stent. TRIAL DESIGN: EVOLVE Short DAPT is a prospective, single-arm, international study that enrolled 2009 high risk bleeding subjects (defined as age ≥75 years, chronic anticoagulation, major bleeding within 12 months, history of stroke, renal insufficiency/failure, or thrombocytopenia) who underwent PCI with the SYNERGY stent. Subjects presenting with acute MI or complex lesions were excluded. After 3 months treatment with DAPT (except those on anticoagulant in whom aspirin is optional), subjects free from stroke, MI, revascularization or ST will be eligible to discontinue P2Y12 inhibitor, but continue aspirin. Co-primary endpoints assessed between 3-15 months are: i) death/MI compared for non-inferiority with propensity-adjusted historical group receiving 12-month DAPT, and ii) definite/probable ST compared to a performance goal. The secondary endpoint is the rate of bleeding in subjects not receiving chronic anticoagulation compared for superiority against a propensity-adjusted historical control. CONCLUSION: The EVOLVE Short DAPT study will prospectively define the safety of DAPT discontinuation at 3 months in high bleeding risk patients treated with the SYNERGY stent.


Assuntos
Aspirina/administração & dosagem , Clopidogrel/administração & dosagem , Doença da Artéria Coronariana/terapia , Stents Farmacológicos , Hemorragia/epidemiologia , Intervenção Coronária Percutânea , Inibidores da Agregação Plaquetária/uso terapêutico , Idoso , Brasil/epidemiologia , Doença da Artéria Coronariana/complicações , Relação Dose-Resposta a Droga , Quimioterapia Combinada , Europa (Continente)/epidemiologia , Feminino , Hemorragia/complicações , Humanos , Incidência , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Resultado do Tratamento , Estados Unidos/epidemiologia
7.
Am Heart J ; 190: 76-85, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28760216

RESUMO

This white paper provides a summary of presentations, discussions and conclusions of a Thinktank entitled "The Role of Endpoint Adjudication in Medical Device Clinical Trials". The think tank was cosponsored by the Cardiac Safety Research Committee, MDEpiNet and the US Food and Drug Administration (FDA) and was convened at the FDA's White Oak headquarters on March 11, 2016. Attention was focused on tailoring best practices for evaluation of endpoints in medical device clinical trials, practical issues in endpoint adjudication of therapeutic, diagnostic, biomarker and drug-device combinations, and the role of adjudication in regulatory and reimbursement issues throughout the device lifecycle. Attendees included representatives from medical device companies, the FDA, Centers for Medicare and Medicaid Services (CMS), end point adjudication specialist groups, clinical research organizations, and active, academically based adjudicators. The manuscript presents recommendations from the think tank regarding (1) rationale for when adjudication is appropriate, (2) best practices establishment and operation of a medical device adjudication committee and (3) the role of endpoint adjudication for post market evaluation in the emerging era of real world evidence.


Assuntos
Pesquisa Biomédica , Doenças Cardiovasculares/terapia , Determinação de Ponto Final/normas , Equipamentos e Provisões , Vigilância de Produtos Comercializados/métodos , Humanos , Estados Unidos , United States Food and Drug Administration
8.
J Magn Reson Imaging ; 46(3): 704-714, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28306210

RESUMO

PURPOSE: To simultaneously assess reproducibility of three MRI transverse relaxation parameters ( R2', R2*, and R2 ) for brain tissue oxygenation mapping and to assess changes in these parameters with inhalation of gases that increase and decrease oxygenation, to identify the most sensitive parameter for imaging brain oxygenation. MATERIALS AND METHODS: Forty-eight healthy subjects (25 male, ages 35 ± 8 years) were scanned at 3.0 Tesla, each with one of four gases (mildly and strongly hypercapnic and hypoxic) administered in a challenge paradigm, using a gas delivery setup designed for patient use. Cerebral blood flow mapping with arterial spin labeling, and simultaneous R2', R2*, and R2 mapping with gradient-echo sampling of free induction decay and echo (GESFIDE) were performed. Reproducibility in air and gas-induced changes were evaluated using nonparametric analysis with correction for multiple comparisons. RESULTS: Our gas delivery setup achieved stable gas challenges as shown by physiological monitoring. Test-retest variability of R2', R2*, and R2 were found to be 0.24 s-1 (8.6% of mean), 0.24 s-1 (1.3% of mean), and 0.15 s-1 (1.0% of mean), respectively. Strong hypoxia produced the most conclusive oxygenation-driven relaxation change, inducing increases in R2' (25 ± 13%, P = 0.03), R2* (5 ± 2%, P = 0.02), and R2 (2 ± 2%, NS). CONCLUSION: We benchmarked the intra-scan test-retest variability in GESFIDE-based transverse relaxation rate mapping. Using a reliable framework for gas challenge paradigms, we recommend strong hypoxia for validating oxygenation mapping methods, and the use of tissue R2' change, instead of R2* or R2 , as a metric for studying brain tissue oxygenation using transverse relaxation methods. LEVEL OF EVIDENCE: 1 Technical Efficacy: Stage 1 J. MAGN. RESON. IMAGING 2017;46:704-714.


Assuntos
Encéfalo/metabolismo , Hipercapnia/metabolismo , Hipóxia/metabolismo , Imageamento por Ressonância Magnética/métodos , Oxigênio/metabolismo , Adulto , Benchmarking , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico/métodos , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Processamento de Imagem Assistida por Computador , Masculino , Reprodutibilidade dos Testes
9.
Circulation ; 131(1): 62-73, 2015 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-25400062

RESUMO

BACKGROUND: The TAXUS Liberté Post Approval Study (TL-PAS) contributed patients treated with TAXUS Liberté paclitaxel-eluting stent and prasugrel to the Dual Antiplatelet Therapy Study (DAPT) that compared 12 and 30 months thienopyridine plus aspirin therapy after drug-eluting stents. METHODS AND RESULTS: Outcomes for 2191 TL-PAS patients enrolled into DAPT were assessed. The DAPT coprimary composite end point (death, myocardial infarction [MI], or stroke) was lower with 30 compared with 12 months prasugrel treatment (3.7% versus 8.8%; hazard ratio [HR], 0.407; P<0.001). Rates of death and stroke were similar between groups, but MI was significantly reduced with prolonged prasugrel treatment (1.9% versus 7.1%; HR, 0.255; P<0.001). The DAPT coprimary end point, stent thrombosis, was also lower with longer therapy (0.2% versus 2.9%; HR, 0.063; P<0.001). MI related to stent thrombosis (0% versus 2.6%; P<0.001) and occurring spontaneously (1.9% versus 4.5%; HR, 0.407; P=0.007) were both reduced with prolonged prasugrel. MI rates increased within 90 days of prasugrel cessation after both 12 and 30 months treatment. Composite Global Utilization of Streptokinase and Tissue Plasminogen Activator for Occluded Coronary Arteries (GUSTO) moderate or severe bleeds were modestly increased (2.4% versus 1.7%; HR, 1.438; P=0.234) but severe bleeds were not more frequent (0.3% versus 0.5%; HR, 0.549; P=0.471) in the prolonged treatment group. CONCLUSIONS: Prasugrel and aspirin continued for 30 months reduced ischemic events for the TAXUS Liberté paclitaxel-eluting stent patient subset from DAPT through reductions in MI and stent thrombosis. Withdrawal of prasugrel was followed by an increase in MI after both 12 and 30 months therapy. The optimal duration of dual antiplatelet therapy with prasugrel after TAXUS Liberté paclitaxel-eluting stent remains unknown, but appears to be >30 months. CLINICAL TRIAL REGISTRATION URL: http://www.clinicaltrials.gov. Unique identifier: NCT00997503.


Assuntos
Aspirina/uso terapêutico , Doença das Coronárias/terapia , Stents Farmacológicos , Paclitaxel/uso terapêutico , Piperazinas/uso terapêutico , Antagonistas do Receptor Purinérgico P2Y/uso terapêutico , Tiofenos/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Humanos , Incidência , Internacionalidade , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/epidemiologia , Inibidores da Agregação Plaquetária/uso terapêutico , Cloridrato de Prasugrel , Piridinas/uso terapêutico , Fatores de Tempo , Resultado do Tratamento
10.
Magn Reson Med ; 73(3): 1228-36, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24753286

RESUMO

PURPOSE: R2', the reversible component of transverse relaxation, is an important susceptibility measurement for studies of brain physiology and pathologies. In existing literature, different R2' measurement methods are used with assumption of equivalency. This study explores the choice of measurement method in healthy, young subjects at 3T. METHODS: In this study, a modified gradient-echo sampling of free induction decay and echo (GESFIDE) sequence was used to compare four standard R2' measurement methods: asymmetric spin echo (ASE), standard GESFIDE, gradient echo sampling of the spin echo (GESSE), and separate R2 and R2* mapping. RESULTS: GESSE returned lower R2' measurements than other methods (P < 0.05). Intersubject mean R2' in gray matter was found to be 2.7 s(-1) using standard GESFIDE and GESSE, versus 3.4-3.8 s(-1) using other methods. In white matter, mean R2' from GESSE was 2.3 s(-1) while other methods produced 3.7-4.3 s(-1) . R2 correction was applied to partially reduce the discrepancies between the methods, but significant differences remained, likely due to violation of the fundamental assumption of a single-compartmental tissue model, and hence monoexponential decay. CONCLUSION: R2' measurements are influenced significantly by the choice of method. Awareness of this issue is important when designing and interpreting studies that involve R2' measurements.


Assuntos
Algoritmos , Encéfalo/anatomia & histologia , Encéfalo/fisiologia , Interpretação de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Adulto , Impedância Elétrica , Feminino , Humanos , Masculino , Valores de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
11.
NMR Biomed ; 28(9): 1163-73, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26224287

RESUMO

The aim of this study was to determine the ability of multiparametric MRI to identify the early effects of individual treatment, during combined chemo-radiotherapy on brain tumours. Eighty male rats bearing 9L gliosarcomas were randomized into four groups: untreated, anti-angiogenic therapy (SORA group), microbeam radiation therapy (MRT group) and both treatments (MRT+SORA group). Multiparametric MRI (tumour volume, diffusion-weighted MR imaging (ADC), blood volume fraction (BVf), microvessel index (VSI), vessel wall integrity (AUC(P846)) and tissue oxygen saturation (StO2)) was performed 1 day before and 2, 5 and 8 days after treatment initiation. Unpaired t-tests and one-way ANOVA were used for statistical analyses. Each MR parameter measured in our protocol was revealed to be sensitive to tumour changes induced by any of the therapies used (individually or combined). When compared with untreated tumours, SORA induced a decrease in BVf, VSI, StO2 and AUC(P846), MRT generated an increase in ADC and AUC(P846) and combined therapies yielded mixed effects: an increase in ADC and AUC(P846) and a decrease in BVf, StO2 and AUC(P846). MRT and MRT+SORA significantly slowed tumour growth. Despite these two groups presenting with similar tumour sizes, the information yielded from MR multiparameter assessment indicated that, when used concomitantly, each therapy induced distinguishable and appreciable physiological changes in the tumour. Our results suggest that multiparametric MRI can monitor the effects of individual treatments, used concomitantly, on brain tumours. Such monitoring would be useful for the detection of tumour resistance to drug/radiotherapy in patients undergoing concomitant therapies.


Assuntos
Neoplasias Encefálicas/terapia , Imageamento por Ressonância Magnética/métodos , Inibidores da Angiogênese/uso terapêutico , Animais , Biomarcadores , Neoplasias Encefálicas/patologia , Masculino , Medicina de Precisão , Ratos , Ratos Endogâmicos F344
12.
J Magn Reson Imaging ; 41(2): 424-30, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24419985

RESUMO

PURPOSE: To investigate if delays in resting-state spontaneous fluctuations of the BOLD (sfBOLD) signal can be used to create maps similar to time-to-maximum of the residue function (Tmax) in Moyamoya patients and to determine whether sfBOLD delays affect the results of brain connectivity mapping. MATERIALS AND METHODS: Ten patients were scanned at 3 Tesla using a gradient-echo echo planar imaging sequence for sfBOLD imaging. Cross correlation analysis was performed between each brain voxel signal and a reference signal comprised of either the superior sagittal sinus (SSS) or whole brain (WB) average time course. sfBOLD delay maps were created based on the time shift necessary to maximize the correlation coefficient, and compared with dynamic susceptibility contrast Tmax maps. Standard and time-shifted resting-state BOLD connectivity analyses of the default mode network were compared. RESULTS: Good linear correlations were found between sfBOLD delays and Tmax using the SSS as reference (r(2) = 0.8, slope = 1.4, intercept = -4.6) or WB (r(2) = 0.7, slope = 0.8, intercept = -3.2). New nodes of connectivity were found in delayed regions when accounting for delays in the analysis. CONCLUSION: Resting-state sfBOLD imaging can create delay maps similar to Tmax maps without the use of contrast agents in Moyamoya patients. Accounting for these delays may affect the results of functional connectivity maps.


Assuntos
Mapeamento Encefálico/métodos , Imageamento por Ressonância Magnética/métodos , Doença de Moyamoya/patologia , Adulto , Idoso , Meios de Contraste , Imagem Ecoplanar , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Masculino , Meglumina/análogos & derivados , Pessoa de Meia-Idade , Compostos Organometálicos , Estudos Prospectivos
13.
Arterioscler Thromb Vasc Biol ; 34(7): 1374-81, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24812325

RESUMO

OBJECTIVE: Obesity associates with increased numbers of inflammatory cells in adipose tissue (AT), including T cells, but the mechanism of T-cell recruitment remains unknown. This study tested the hypothesis that the chemokine (C-X-C motif) receptor 3 (CXCR3) participates in T-cell accumulation in AT of obese mice and thus in the regulation of local inflammation and systemic metabolism. APPROACH AND RESULTS: Obese wild-type mice exhibited higher mRNA expression of CXCR3 in periepididymal AT-derived stromal vascular cells compared with lean mice. We evaluated the function of CXCR3 in AT inflammation in vivo using CXCR3-deficient and wild-type control mice that consumed a high-fat diet. Periepididymal AT from obese CXCR3-deficient mice contained fewer T cells than obese controls after 8 and 16 weeks on high-fat diet, as assessed by flow cytometry. Obese CXCR3-deficient mice had greater glucose tolerance than obese controls after 8 weeks, but not after 16 weeks. CXCR3-deficient mice fed high-fat diet had reduced mRNA expression of proinflammatory mediators, such as monocyte chemoattractant protein-1 and regulated on activation, normal T cell expressed and secreted, and anti-inflammatory genes, such as Foxp3, IL-10, and arginase-1 in periepididymal AT, compared with obese controls. CONCLUSIONS: These results demonstrate that CXCR3 contributes to T-cell accumulation in periepididymal AT of obese mice. Our results also suggest that CXCR3 regulates the accumulation of distinct subsets of T cells and that the ratio between these functional subsets across time likely modulates local inflammation and systemic metabolism.


Assuntos
Tecido Adiposo/imunologia , Quimiotaxia de Leucócito , Obesidade/imunologia , Paniculite/imunologia , Receptores CXCR3/metabolismo , Subpopulações de Linfócitos T/imunologia , Tecido Adiposo/metabolismo , Animais , Modelos Animais de Doenças , Regulação da Expressão Gênica , Mediadores da Inflamação/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Obesidade/genética , Obesidade/metabolismo , Paniculite/genética , Paniculite/metabolismo , Receptores CXCR3/deficiência , Receptores CXCR3/genética , Transdução de Sinais , Subpopulações de Linfócitos T/metabolismo , Fatores de Tempo
14.
Magn Reson Med ; 72(3): 646-58, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24167116

RESUMO

PURPOSE: MRI is used to obtain quantitative oxygenation and blood volume information from the susceptibility-related MR signal dephasing induced by blood vessels. However, analytical models that fit the MR signal are usually not accurate over the range of small blood vessels. Moreover, recent studies have demonstrated limitations in the simultaneous assessment of oxygenation and blood volume. In this study, a multiparametric MRI framework that aims to measure vessel radii in addition to magnetic susceptibility and volume fraction was introduced. METHODS: The protocol consisted of gradient-echo sampling of the spin-echo, diffusion, T2, and B0 acquisitions. After correction steps, the data were postprocessed with a versatile numerical model of the MR signal. An important analytical model was implemented for comparison. The approach was validated in phantoms with coiling strings as proxy for blood vessels. RESULTS: The feasibility of the vessel radius measurement is demonstrated. The numerical model shows an improved accuracy compared with the analytical approach. However, both methods overestimate the radius. The simultaneous measurement of the magnetic susceptibility and the volume fraction remains challenging. CONCLUSION: The results suggest that this approach could be interesting in vivo to better characterize the microvasculature without contrast agent.


Assuntos
Imagem de Difusão por Ressonância Magnética/métodos , Angiografia por Ressonância Magnética/métodos , Microcirculação , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imagens de Fantasmas
15.
Circ Cardiovasc Qual Outcomes ; 17(10): e011007, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39364591

RESUMO

BACKGROUND: Long-term outcomes following left atrial appendage occlusion outside clinical trials and small registries are largely unknown. Collecting these data was a condition of US market authorization of the WATCHMAN device. The aim of this analysis was to evaluate the rates of stroke, bleeding, and death among Medicare beneficiaries following left atrial appendage occlusion implantation during initial commercial availability of the WATCHMAN left atrial appendage occlusion device overall and in important subgroups. METHODS: All Medicare fee-for-service beneficiaries ≥65 years of age who underwent left atrial appendage occlusion from April 1, 2016, to August 31, 2020, were included based on the International Classification of Diseases, Tenth Revision, and Current Procedural Terminology codes. Over a 5-year follow-up period, the cumulative incidence over time of mortality, ischemic stroke, and major bleeding were calculated using the International Classification of Diseases, Tenth Revision, diagnosis codes for the full study cohort and within important prespecified subgroups. RESULTS: WATCHMAN recipients (n=48 763) were a median of 77 (interquartile range, 72-82) years of age, 42% female, and mostly White (93%). The median CHA2DS2VASc score was 4 (interquartile range, 3-5) with prior major bleeding in 42% and prior stroke in 12%. At 5 years, death occurred in 44%, bleeding in 15% (with higher risk early following implantation), and ischemic stroke in 7%. Each of these end points was more common with greater baseline age. Male patients had greater 5-year mortality than female patients (46.9% versus 40.6%), but there was no difference between sexes in the rates of ischemic stroke (6.6% versus 7.5%) or major bleeding (14.9% for both). WATCHMAN recipients with prior ischemic stroke or a major bleeding event were older and frailer; these groups had higher rates of ischemic stroke, major bleeding, and death. CONCLUSIONS: Compared with patients enrolled in the pivotal clinical trials, Medicare beneficiaries undergoing WATCHMAN implantation were older, more female, and had more comorbid conditions. Substantial long-term mortality and major bleeding following WATCHMAN reflect the high-risk nature of the patient population, while the ischemic stroke rate was relatively low (<1.5% per year).


Assuntos
Apêndice Atrial , Fibrilação Atrial , Hemorragia , Benefícios do Seguro , AVC Isquêmico , Medicare , Humanos , Feminino , Idoso , Masculino , Estados Unidos/epidemiologia , Idoso de 80 Anos ou mais , Fatores de Tempo , Resultado do Tratamento , Fatores de Risco , Medição de Risco , Apêndice Atrial/cirurgia , AVC Isquêmico/mortalidade , AVC Isquêmico/epidemiologia , AVC Isquêmico/diagnóstico , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/mortalidade , Fibrilação Atrial/terapia , Hemorragia/epidemiologia , Incidência , Estudos Retrospectivos , Planos de Pagamento por Serviço Prestado , Cateterismo Cardíaco/efeitos adversos , Cateterismo Cardíaco/instrumentação , Cateterismo Cardíaco/mortalidade
16.
J Am Coll Cardiol ; 84(10): 889-900, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39197978

RESUMO

BACKGROUND: The prevalence of and outcomes associated with different antithrombotic strategies after left atrial appendage occlusion (LAAO) are not well described. OBJECTIVES: This study sought to evaluate patterns of antithrombotic medication strategies at discharge following LAAO with the Watchman FLX device in real-world practice and to compare the risk of adverse events among the different antithrombotic regimens. METHODS: The authors evaluated patients in the NCDR (National Cardiovascular Data Registry) LAAO Registry who underwent LAAO with the second-generation LAA closure device between 2020 and 2022. They grouped patients by mutually exclusive discharge antithrombotic strategies and compared the rates of adverse events at 45 days and 6 months using multivariable Cox proportional hazards regression. RESULTS: Among 53,878 patients undergoing successful LAAO with the second-generation LAA closure device, the most common antithrombotic discharge regimens were direct oral anticoagulant (DOAC) plus aspirin (48.3%), DOAC alone (22.6%), dual antiplatelet therapy (8.1%), warfarin plus aspirin (7.7%), and DOAC plus P2Y12 inhibitor (4.9%). In multivariate analysis, DOAC alone had a lower rate of major adverse events and major bleeding at 45 days of follow-up compared with DOAC plus aspirin (major adverse events: HR: 0.78; 95% CI: 0.68-0.91; major bleeding: HR: 0.69; 95% CI: 0.60-0.80). These differences persisted at 6 months. Warfarin without aspirin also showed lower rates of major bleeding at both time points. No differences were seen in stroke/transient ischemic attack or device-related thrombus. CONCLUSIONS: In real-world U.S. practice, discharge on DOAC alone or warfarin alone was associated with a lower rate of adverse events compared with DOAC plus aspirin.


Assuntos
Anticoagulantes , Aspirina , Apêndice Atrial , Fibrilação Atrial , Inibidores da Agregação Plaquetária , Humanos , Apêndice Atrial/cirurgia , Masculino , Feminino , Aspirina/administração & dosagem , Aspirina/efeitos adversos , Aspirina/uso terapêutico , Idoso , Fibrilação Atrial/tratamento farmacológico , Fibrilação Atrial/complicações , Anticoagulantes/administração & dosagem , Anticoagulantes/efeitos adversos , Inibidores da Agregação Plaquetária/administração & dosagem , Inibidores da Agregação Plaquetária/efeitos adversos , Inibidores da Agregação Plaquetária/uso terapêutico , Sistema de Registros , Idoso de 80 Anos ou mais , Terapia Antiplaquetária Dupla/métodos , Quimioterapia Combinada , Acidente Vascular Cerebral/prevenção & controle , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/epidemiologia , Pessoa de Meia-Idade
17.
Circ Cardiovasc Interv ; 17(9): e013750, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39056187

RESUMO

BACKGROUND: PINNACLE FLX (Protection Against Embolism for Nonvalvular AF Patients: Investigational Device Evaluation of the WATCHMAN FLX LAA Closure Technology) demonstrated improved outcomes and low incidence of adverse events with the WATCHMAN FLX device in a controlled setting. The National Cardiovascular Disease Registry's Left Atrial Appendage Occlusion Registry was utilized to assess the safety and effectiveness of WATCHMAN FLX in contemporary clinical practice in the United States. METHODS: The WATCHMAN FLX Device Surveillance Post Approval Analysis Plan used data from the Left Atrial Appendage Occlusion registry to identify patients undergoing WATCHMAN FLX implantation between August 2020 and September 2022. The key safety end point was defined as all-cause death, ischemic stroke, systemic embolism, or device or procedure-related events requiring open cardiac surgery or major endovascular intervention between device implantation and hospital discharge. Major adverse events were reported at hospital discharge, 45 days, and 1 year. RESULTS: Among 97 185 patients in the Left Atrial Appendage Occlusion registry undergoing WATCHMAN FLX, successful implantation occurred in 97.5% (n=94 784) of patients. The key safety end point occurred in 0.45% of patients. At 45 days post-procedure, all-cause death occurred in 0.81% patients, ischemic stroke in 0.23%, major bleeding in 3.1%, pericardial effusion requiring intervention in 0.50%, device-related thrombus in 0.44%, and device embolism in 0.04% patients. No peri-device leak was observed in 83.1% of patients at 45 days. At 1 year, the rate of all-cause death was 8.2%, the rate of any stroke was 1.5% (ischemic stroke, 1.2%), and major bleeding occurred in 6.4% of patients. CONCLUSIONS: In a large contemporary cohort of patients with the WATCHMAN FLX device, the rates of implant success and clinical outcomes through 1 year were comparable with the PINNACLE FLX study, demonstrating that favorable outcomes achieved in the pivotal approval study can be replicated in routine clinical practice.


Assuntos
Apêndice Atrial , Fibrilação Atrial , Sistema de Registros , Humanos , Apêndice Atrial/fisiopatologia , Feminino , Masculino , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/terapia , Fibrilação Atrial/mortalidade , Fibrilação Atrial/fisiopatologia , Idoso , Resultado do Tratamento , Estados Unidos , Fatores de Tempo , Fatores de Risco , Idoso de 80 Anos ou mais , Cateterismo Cardíaco/efeitos adversos , Cateterismo Cardíaco/instrumentação , Cateterismo Cardíaco/mortalidade , Medição de Risco , Vigilância de Produtos Comercializados , Dispositivos de Proteção Embólica , AVC Isquêmico/prevenção & controle , AVC Isquêmico/mortalidade , AVC Isquêmico/etiologia , Desenho de Prótese , Pessoa de Meia-Idade
18.
Magn Reson Med ; 70(3): 705-10, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23001902

RESUMO

Cerebral blood volume maps are usually acquired using dynamic susceptibility contrast imaging which inherently limits the spatial resolution and signal to noise ratio of the images. In this study, we used ferumoxytol (AMAG Pharmaceuticals, Inc., Cambridge, MA), an FDA-approved compound, to obtain high-resolution cerebral blood volume maps with a steady-state approach in seven healthy volunteers. R2* maps (0.8 × 0.8 × 1 mm(3)) were acquired before and after injection of ferumoxytol and an intraindividual normalization protocol was used to obtain quantitative values. The results show excellent contrast between white and gray matter as well as fine highly detailed vascular structures. An average blood volume of 4% was found in the brain of all volunteers, consistent with prior literature values. A linear relationship was found between ferumoxytol dose (mg/kg) and ΔR2* (1/s) in gray (R(2) = 0.98) and white matter (R(2) = 0.98). A quadratic relationship was found in the sagittal sinus (R(2) = 0.98). The cerebral blood volume maps compare well with lower resolution dynamic susceptibility contrast-MRI and their use should improve the evaluation of small and heterogeneous lesions and facilitate intrapatient and interpatient comparisons.


Assuntos
Volume Sanguíneo , Circulação Cerebrovascular , Meios de Contraste , Óxido Ferroso-Férrico , Imageamento por Ressonância Magnética/métodos , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
19.
Nat Med ; 12(8): 950-4, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16862155

RESUMO

A genetic polymorphism in the human gene encoding connexin37 (CX37, encoded by GJA4, also known as CX37) has been reported as a potential prognostic marker for atherosclerosis. The expression of this gap-junction protein is altered in mouse and human atherosclerotic lesions: it disappears from the endothelium of advanced plaques but is detected in macrophages recruited to the lesions. The role of CX37 in atherogenesis, however, remains unknown. Here we have investigated the effect of deleting the mouse connexin37 (Cx37) gene (Gja4, also known as Cx37) on atherosclerosis in apolipoprotein E-deficient (Apoe(-/-)) mice, an animal model of this disease. We find that Gja4(-/-)Apoe(-/-) mice develop more aortic lesions than Gja4(+/+)Apoe(-/-) mice that express Cx37. Using in vivo adoptive transfer, we show that monocyte and macrophage recruitment is enhanced by eliminating expression of Cx37 in these leukocytes but not by eliminating its expression in the endothelium. We further show that Cx37 hemichannel activity in primary monocytes, macrophages and a macrophage cell line (H36.12j) inhibits leukocyte adhesion. This antiadhesive effect is mediated by release of ATP into the extracellular space. Thus, Cx37 hemichannels may control initiation of the development of atherosclerotic plaques by regulating monocyte adhesion. H36.12j macrophages expressing either of the two CX37 proteins encoded by a polymorphism in the human GJA4 gene show differential ATP-dependent adhesion. These results provide a potential mechanism by which a polymorphism in CX37 protects against atherosclerosis.


Assuntos
Aterosclerose/prevenção & controle , Conexinas/genética , Conexinas/metabolismo , Regulação da Expressão Gênica , Monócitos/fisiologia , Trifosfato de Adenosina/metabolismo , Transferência Adotiva , Animais , Aorta Torácica/patologia , Apolipoproteínas E/deficiência , Apolipoproteínas E/genética , Aterosclerose/metabolismo , Aterosclerose/patologia , Adesão Celular , Linhagem Celular , Células Cultivadas , Colesterol na Dieta/administração & dosagem , Cruzamentos Genéticos , Modelos Animais de Doenças , Endotélio Vascular/citologia , Endotélio Vascular/metabolismo , Espaço Extracelular/metabolismo , Macrófagos Peritoneais/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Polimorfismo Genético
20.
Med Image Anal ; 88: 102799, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37245434

RESUMO

ImUnity is an original 2.5D deep-learning model designed for efficient and flexible MR image harmonization. A VAE-GAN network, coupled with a confusion module and an optional biological preservation module, uses multiple 2D slices taken from different anatomical locations in each subject of the training database, as well as image contrast transformations for its training. It eventually generates 'corrected' MR images that can be used for various multi-center population studies. Using 3 open source databases (ABIDE, OASIS and SRPBS), which contain MR images from multiple acquisition scanner types or vendors and a large range of subjects ages, we show that ImUnity: (1) outperforms state-of-the-art methods in terms of quality of images generated using traveling subjects; (2) removes sites or scanner biases while improving patients classification; (3) harmonizes data coming from new sites or scanners without the need for an additional fine-tuning and (4) allows the selection of multiple MR reconstructed images according to the desired applications. Tested here on T1-weighted images, ImUnity could be used to harmonize other types of medical images.


Assuntos
Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Humanos , Bases de Dados Factuais , Estudos Multicêntricos como Assunto
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