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1.
Int J Toxicol ; 42(3_suppl): 27S-28S, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37769692

RESUMO

The Expert Panel for Cosmetic Ingredient Safety reviewed newly available studies since their original assessment in 2001, along with updated information regarding product types and concentrations of use, and confirmed that Cottonseed Glyceride and Hydrogenated Cottonseed Glyceride are safe as cosmetic ingredients in the practices of use and concentration as described in this report, provided that established and imposed limits on gossypol, heavy metals, and pesticide concentrations are not exceeded.


Assuntos
Cosméticos , Gossipol , Óleo de Sementes de Algodão , Qualidade de Produtos para o Consumidor , Testes de Toxicidade , Glicerídeos
2.
Int J Toxicol ; 42(3_suppl): 29S-31S, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37751575

RESUMO

The Expert Panel for Cosmetic Ingredient Safety reviewed updated information that has become available since their original assessment from 2004, along with updated information regarding product types, and frequency and concentrations of use, and reaffirmed their original conclusion that Dioscorea Villosa (Wild Yam) Root Extract is safe as a cosmetic ingredient in the practices of use and concentration as described in this report.


Assuntos
Cosméticos , Dioscorea , Extratos Vegetais/toxicidade , Qualidade de Produtos para o Consumidor
5.
Redox Biol ; 39: 101840, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33360352

RESUMO

The localization of NQO1 near acetylated microtubules has led to the hypothesis that NQO1 may work in concert with the NAD+-dependent deacetylase SIRT2 to regulate acetyl α-tubulin (K40) levels on microtubules. NQO1 catalyzes the oxidation of NADH to NAD+ and may supplement levels of NAD+ near microtubules to aid SIRT2 deacetylase activity. While HDAC6 has been shown to regulate the majority of microtubule acetylation at K40, SIRT2 is also known to modulate microtubule acetylation (K40) in the perinuclear region. In this study we examined the potential roles NQO1 may play in modulating acetyl α-tubulin levels. Knock-out or knock-down of NQO1 or SIRT2 did not change the levels of acetyl α-tubulin in 16HBE human bronchial epithelial cells and 3T3-L1 fibroblasts; however, treatment with a mechanism-based inhibitor of NQO1 (MI2321) led to a short-lived temporal increase in acetyl α-tubulin levels in both cell lines without impacting the intracellular pools of NADH or NAD+. Inactivation of NQO1 by MI2321 resulted in lower levels of NQO1 immunostaining on microtubules, consistent with redox-dependent changes in NQO1 conformation as evidenced by the use of redox-specific, anti-NQO1 antibodies in immunoprecipitation studies. Given the highly dynamic nature of acetylation-deacetylation reactions at α-tubulin K40 and the crowded protein environment surrounding this site, disruption in the binding of NQO1 to microtubules may temporally disturb the physical interactions of enzymes responsible for maintaining the microtubule acetylome.


Assuntos
Microtúbulos , Tubulina (Proteína) , Células 3T3-L1 , Acetilação , Animais , Humanos , Camundongos , Microtúbulos/metabolismo , NAD(P)H Desidrogenase (Quinona)/genética , NAD(P)H Desidrogenase (Quinona)/metabolismo , Oxirredução , Sirtuína 2/metabolismo , Tubulina (Proteína)/metabolismo
6.
Med Care ; 58(5): e31-e38, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32187105

RESUMO

BACKGROUND: The Department of Veterans Affairs (VA) cares for more patients with hepatitis C virus (HCV) than any other US health care system. We tracked the implementation strategies that VA sites used to implement highly effective new treatments for HCV with the aim of uncovering how combinations of implementation strategies influenced the uptake of the HCV treatment innovation. We applied Configurational Comparative Methods (CCMs) to uncover causal dependencies and identify difference-making strategy configurations, and to distinguish higher from lower HCV treating sites. METHODS: We surveyed providers to assess VA sites' use of 73 implementation strategies to promote HCV treatment in the fiscal year 2015. CCMs were used to identify strategy configurations that uniquely distinguished higher HCV from lower HCV treating sites. RESULTS: From the 73 possible implementation strategies, CCMs identified 5 distinct strategy configurations, or "solution paths." These were comprised of 10 individual strategies that collectively explained 80% of the sites with higher HCV treatment starts with 100% consistency. Using any one of the following 5 solution paths was sufficient to produce higher treatment starts: (1) technical assistance; (2) engaging in a learning collaborative AND designating leaders; (3) site visits AND outreach to patients to promote uptake and adherence; (4) developing resource sharing agreements AND an implementation blueprint; OR (5) creating new clinical teams AND sharing quality improvement knowledge with other sites AND engaging patients. There was equifinality in that the presence of any one of the 5 solution paths was sufficient for higher treatment starts. CONCLUSIONS: Five strategy configurations distinguished higher HCV from lower HCV treating sites with 100% consistency. CCMs represent a methodological advancement that can help inform high-yield implementation strategy selection and increase the efficiency and effectiveness of future implementation efforts.


Assuntos
Antivirais/uso terapêutico , Procedimentos Clínicos , Hepatite C/tratamento farmacológico , Adesão à Medicação , Humanos , Avaliação de Programas e Projetos de Saúde , Estados Unidos , United States Department of Veterans Affairs , Serviços de Saúde para Veteranos Militares
7.
Hemasphere ; 3(3): e224, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31723837

RESUMO

The significant morbidity and mortality associated with iron overload can be reduced by effective iron chelation. Magnetic resonance imaging (MRI) provides accurate and reproducible iron load assessment. The aim of this epidemiological study was to assess the prevalence and severity of cardiac and hepatic siderosis by MRI and to evaluate the impact of MRI on clinical management in patients with transfusion-dependent anemia and non-transfusion-dependent thalassemia (NTDT). We enrolled 243 patients with myelodysplastic syndromes (MDS), thalassemia major (TM), NTDT or other chronic anemia. Overall, 10% and 48% had cardiac and hepatic siderosis, respectively. Mean liver iron concentration (LIC) was above target range in all groups; mean myocardial T2∗ was normal. Hepatic siderosis was more prevalent than myocardial siderosis in patients with MDS, occurring in 54.4% and 4.4% of patients, respectively. As also observed in patients with NTDT or other anemia, hepatic siderosis was present in a large proportion of MDS patients who were chelation naïve (57.7%), as well as in patients receiving iron chelation therapy (ICT) (52.4%), despite a lower transfusion load compared with TM. Correlation between LIC and serum ferritin was observed across diseases; however, not all patients requiring ICT could be identified with serum ferritin alone, as serum ferritin underestimated LIC in 4.4% and overestimated LIC in 7.5% of patients. Exploratory analyses showed serum ferritin thresholds for liver siderosis detected by MRI at approximately 300 ng/mL higher in MDS than in TM. Most patients reported low-medium adherence to ICT; MRI assessment led to change in ICT in 46% of evaluable patients, including 52% of MDS patients. Accurate organ iron monitoring by MRI facilitated appropriate initiation of chelation, dose optimization and clinical decision making. Trial registration: ClinicalTrials.gov: NCT01736540.

8.
J Grad Med Educ ; 11(3): 274-276, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31210856
9.
Circulation ; 139(19): 2238-2255, 2019 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-30759996

RESUMO

BACKGROUND: Deficiencies of iron-sulfur (Fe-S) clusters, metal complexes that control redox state and mitochondrial metabolism, have been linked to pulmonary hypertension (PH), a deadly vascular disease with poorly defined molecular origins. BOLA3 (BolA Family Member 3) regulates Fe-S biogenesis, and mutations in BOLA3 result in multiple mitochondrial dysfunction syndrome, a fatal disorder associated with PH. The mechanistic role of BOLA3 in PH remains undefined. METHODS: In vitro assessment of BOLA3 regulation and gain- and loss-of-function assays were performed in human pulmonary artery endothelial cells using siRNA and lentiviral vectors expressing the mitochondrial isoform of BOLA3. Polymeric nanoparticle 7C1 was used for lung endothelium-specific delivery of BOLA3 siRNA oligonucleotides in mice. Overexpression of pulmonary vascular BOLA3 was performed by orotracheal transgene delivery of adeno-associated virus in mouse models of PH. RESULTS: In cultured hypoxic pulmonary artery endothelial cells, lung from human patients with Group 1 and 3 PH, and multiple rodent models of PH, endothelial BOLA3 expression was downregulated, which involved hypoxia inducible factor-2α-dependent transcriptional repression via histone deacetylase 1-mediated histone deacetylation. In vitro gain- and loss-of-function studies demonstrated that BOLA3 regulated Fe-S integrity, thus modulating lipoate-containing 2-oxoacid dehydrogenases with consequent control over glycolysis and mitochondrial respiration. In contexts of siRNA knockdown and naturally occurring human genetic mutation, cellular BOLA3 deficiency downregulated the glycine cleavage system protein H, thus bolstering intracellular glycine content. In the setting of these alterations of oxidative metabolism and glycine levels, BOLA3 deficiency increased endothelial proliferation, survival, and vasoconstriction while decreasing angiogenic potential. In vivo, pharmacological knockdown of endothelial BOLA3 and targeted overexpression of BOLA3 in mice demonstrated that BOLA3 deficiency promotes histological and hemodynamic manifestations of PH. Notably, the therapeutic effects of BOLA3 expression were reversed by exogenous glycine supplementation. CONCLUSIONS: BOLA3 acts as a crucial lynchpin connecting Fe-S-dependent oxidative respiration and glycine homeostasis with endothelial metabolic reprogramming critical to PH pathogenesis. These results provide a molecular explanation for the clinical associations linking PH with hyperglycinemic syndromes and mitochondrial disorders. These findings also identify novel metabolic targets, including those involved in epigenetics, Fe-S biogenesis, and glycine biology, for diagnostic and therapeutic development.


Assuntos
Endotélio Vascular/fisiologia , Glicina/metabolismo , Hipertensão Pulmonar/genética , Proteínas Mitocondriais/metabolismo , Adolescente , Adulto , Animais , Respiração Celular , Células Cultivadas , Criança , Pré-Escolar , Modelos Animais de Doenças , Feminino , Humanos , Hipertensão Pulmonar/metabolismo , Lactente , Proteínas Ferro-Enxofre/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Mitocondriais/genética , Mutação/genética , Oxirredução , RNA Interferente Pequeno/genética , Adulto Jovem
10.
Europace ; 20(suppl_2): ii11-ii21, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29722861

RESUMO

Aims: Remote magnetic navigation (RMN) is a safe and effective means of performing ventricular tachycardia (VT) ablation. It may have advantages over manual catheter ablation due to ease of manoeuvrability and catheter stability. We sought to compare the safety and efficacy of RMN vs. manual VT ablation. Methods and results: Retrospective study of procedural outcomes of 139 consecutive VT ablation procedures (69 RMN, 70 manual ablation) in 113 patients between 2009 and 2015 was performed. Remote magnetic navigation was associated with overall higher acute procedural success (80% vs. 60%, P = 0.01), with a trend to fewer major complications (3% vs. 9% P = 0.09). Seventy-nine patients were followed up for a median of 17.0 [interquartile range (IQR) 3.0-41.0] months for the RMN group and 15.5 (IQR 6.5-30.0) months for manual ablation group. In the ischaemic cardiomyopathy subgroup, RMN was associated with longer survival from the composite endpoint of VT recurrence leading to defibrillator shock, re-hospitalization or repeat catheter ablation and all-cause mortality; single-procedure adjusted hazard ratio (HR) 0.240 (95% CI 0.070-0.821) P = 0.023, multi-procedure HR 0.170 (95% CI 0.046-0.632) P = 0.002. In patients with implanted defibrillators, multi-procedure VT-free survival was superior with RMN, HR 0.199 (95% CI 0.060-0.657) P = 0.003. Conclusion: Remote magnetic navigation may improve clinical outcomes after catheter ablation of VT in patients with ischaemic cardiomyopathy. Further prospective clinical studies are required to confirm these findings.


Assuntos
Cateterismo Cardíaco/métodos , Ablação por Cateter/métodos , Magnetismo/métodos , Tecnologia de Sensoriamento Remoto/métodos , Cirurgia Assistida por Computador/métodos , Taquicardia Ventricular/cirurgia , Potenciais de Ação , Adulto , Idoso , Cateterismo Cardíaco/efeitos adversos , Cateterismo Cardíaco/instrumentação , Cateterismo Cardíaco/mortalidade , Cateteres Cardíacos , Ablação por Cateter/efeitos adversos , Ablação por Cateter/instrumentação , Ablação por Cateter/mortalidade , Técnicas Eletrofisiológicas Cardíacas , Feminino , Frequência Cardíaca , Humanos , Magnetismo/instrumentação , Imãs , Masculino , Pessoa de Meia-Idade , Recidiva , Tecnologia de Sensoriamento Remoto/instrumentação , Estudos Retrospectivos , Fatores de Risco , Cirurgia Assistida por Computador/efeitos adversos , Cirurgia Assistida por Computador/instrumentação , Cirurgia Assistida por Computador/mortalidade , Taquicardia Ventricular/diagnóstico , Taquicardia Ventricular/mortalidade , Taquicardia Ventricular/fisiopatologia , Fatores de Tempo , Resultado do Tratamento
11.
J Cogn Neurosci ; 30(7): 973-984, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29561239

RESUMO

Visual object expertise correlates with neural selectivity in the fusiform face area (FFA). Although behavioral studies suggest that visual expertise is associated with increased use of holistic and configural information, little is known about the nature of the supporting neural representations. Using high-resolution 7-T functional magnetic resonance imaging, we recorded the multivoxel activation patterns elicited by whole cars, configurally disrupted cars, and car parts in individuals with a wide range of car expertise. A probabilistic support vector machine classifier was trained to differentiate activation patterns elicited by whole car images from activation patterns elicited by misconfigured car images. The classifier was then used to classify new combined activation patterns that were created by averaging activation patterns elicited by individually presented top and bottom car parts. In line with the idea that the configuration of parts is critical to expert visual perception, car expertise was negatively associated with the probability of a combined activation pattern being classified as a whole car in the right anterior FFA, a region critical to vision for categories of expertise. Thus, just as found for faces in normal observers, the neural representation of cars in right anterior FFA is more holistic for car experts than car novices, consistent with common mechanisms of neural selectivity for faces and other objects of expertise in this area.


Assuntos
Mapeamento Encefálico , Discriminação Psicológica/fisiologia , Lateralidade Funcional , Imageamento por Ressonância Magnética , Reconhecimento Visual de Modelos/fisiologia , Competência Profissional , Lobo Temporal/diagnóstico por imagem , Adulto , Automóveis , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Oxigênio/sangue , Estimulação Luminosa , Desempenho Psicomotor/fisiologia , Adulto Jovem
12.
Mol Diagn Ther ; 20(3): 241-53, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27084556

RESUMO

BACKGROUND: Several targeted therapies have been approved for treatment of solid tumors. Identification of gene mutations that indicate response to these therapies is rapidly progressing. A 34-gene next-generation sequencing (NGS) panel, developed and validated by us, was evaluated to detect additional mutations in community-based cancer specimens initially sent to our reference laboratory for routine molecular testing. METHODS: Consecutive de-identified clinical specimens (n = 121) from melanoma cases (n = 31), lung cancer cases (n = 27), colorectal cancer cases (n = 33), and breast cancer cases (n = 30) were profiled by NGS, and the results were compared with routine molecular testing. RESULTS: Upon initial mutation testing, 20 % (24/121) were positive. NGS detected ≥1 additional mutation not identified by routine testing in 74 % of specimens (90/121). Of the specimens with additional mutations, 16 harbored mutations in National Comprehensive Cancer Network guideline genes. These various additional mutations were in gene regions not routinely covered, in genes not routinely tested, and/or present at low allele frequencies. Moreover, NGS yielded no false negatives. Overall, NGS detected mutations in 59 % of the genes (20/34) included in the panel, 75 % of which (15/20) were detected in multiple tumor types. Mutations in TP53 were found in 51 % of tumors tested (62/121). Mutations in at least one other (non-TP53) gene present in the panel were detected in 64 % of cases (77/121). CONCLUSION: This assay provides improved breadth and sensitivity for profiling clinically relevant genes in these prevalent solid tumor types.


Assuntos
Biomarcadores Tumorais , Mutação , Neoplasias/diagnóstico , Neoplasias/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Biópsia , Feminino , Frequência do Gene , Testes Genéticos/métodos , Genótipo , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Metástase Neoplásica , Estadiamento de Neoplasias , Reprodutibilidade dos Testes , Adulto Jovem
13.
Int J Gynaecol Obstet ; 130 Suppl 1: S51-7, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25963906

RESUMO

OBJECTIVE: To assess the operational integration of maternal HIV testing and syphilis screening in Mwanza, Tanzania. METHODS: Interviews were conducted with 76 health workers (HW) from three antenatal clinics (ANC) and three maternity wards in 2008-2009 and 1137 consecutive women admitted for delivery. Nine ANC health education sessions and client flow observations were observed. RESULTS: Only 25.0% of HWs reported they had received training in both prevention of mother-to-child transmission (PMTCT) and syphilis screening. HIV and syphilis tests were sometimes performed in different rooms and results recorded in separate registers with different formats and the results were not always given by the same person. At delivery, most women had been tested for both HIV (79.4%) and syphilis (88.1%) during pregnancy. Of those not tested antenatally for each infection, 70.1% were tested for HIV at delivery but none for syphilis. CONCLUSION: Integration of maternal HIV and syphilis screening was limited. Integrated care guidelines and related health worker training should address this gap.


Assuntos
Prestação Integrada de Cuidados de Saúde/normas , Infecções por HIV/transmissão , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Cuidado Pré-Natal/métodos , Sífilis/transmissão , Adulto , Feminino , Pessoal de Saúde/educação , Humanos , Recém-Nascido , Programas de Rastreamento , Gravidez , Complicações Infecciosas na Gravidez/imunologia , Tanzânia
14.
J Acquir Immune Defic Syndr ; 69(4): 474-80, 2015 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-25835603

RESUMO

BACKGROUND: The Department of Veterans Affairs (VA), the largest integrated HIV care provider in the United States (US), used the HIV Care Continuum to compare clinical care within the VA HIV population with the general US HIV population and to identify areas for improvement. METHODS: National data from the VA's HIV Clinical Case Registry were used to construct measures along the Continuum for Veterans in VA care diagnosed with HIV by June 2013 and alive by December 31, 2013. Comparisons were made to recent estimates for the same measures for the US HIV population. Additional comparisons were performed for demographic subgroups of sex, race/ethnicity, and age. RESULTS: Of 25,480 Veterans diagnosed with HIV, 77.4% were engaged in care compared with 46.3% in the US population diagnosed with HIV (P < 0.001). Seventy-three percent of Veterans diagnosed with HIV received antiretroviral therapy compared with 43% of the US population diagnosed with HIV (P < 0.001). Nearly two-thirds (65.3%) of HIV-diagnosed Veterans had suppressed HIV viral loads compared with 35.0% of the US population diagnosed with HIV (P < 0.001). CONCLUSIONS: The VA health care system performed better at every stage of the HIV Care Continuum compared with the general US estimates. Comparable high rates with some variation were noted among the demographic groups in the VA cohort. The high viral suppression rate in VA, which was almost double the estimate for the HIV-diagnosed US population, demonstrates that improved outcomes along the HIV Care Continuum can be achieved in a comprehensive integrated health care system.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Prestação Integrada de Cuidados de Saúde/estatística & dados numéricos , Infecções por HIV/terapia , United States Department of Veterans Affairs , Adolescente , Adulto , Idoso , Feminino , Infecções por HIV/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Grupos Raciais , Estados Unidos/epidemiologia , Adulto Jovem
15.
Behav Res Methods ; 47(3): 736-43, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24961957

RESUMO

There is growing interest in the study of individual differences in face recognition, including one of its hallmarks, holistic processing, which can be defined as a failure of selective attention to parts. These efforts demand that researchers be aware of, and try to maximize, the reliability of their measurements. Here we report on the reliability of measurements using the composite task (complete design), a measure of holistic processing that has been shown to have relatively good validity. Several studies have used the composite task to investigate individual differences, yet only one study has discussed its reliability. We investigate the reliability of composite-task measurements in eight data sets from five different samples of subjects. In general, we found reliability to be fairly low, but there was substantial variability across experiments. Researchers should keep in mind that reliability is a property of measurements, not of a task, and think about the ways in which measurements in a particular task may be improved before embarking on individual differences research.


Assuntos
Face , Reconhecimento Facial , Individualidade , Reconhecimento Psicológico , Feminino , Humanos , Masculino , Estimulação Luminosa , Reprodutibilidade dos Testes , Adulto Jovem
16.
J Gen Intern Med ; 29 Suppl 4: 831-4, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25355082

RESUMO

We are in a new era of partner-based implementation research, and we need clear strategies for how to navigate this new era. Drawing on principles from community-based participatory research, the Clinical Public Health group of the Department of Veterans Affairs and the HIV/Hepatitis Quality Enhancement Research Initiative (HHQUERI) forged a longstanding partnership that has improved the care of Veterans with Human Immunodeficiency Virus (HIV) and Hepatitis C Virus. An exemplar HIV testing project epitomizes this partnership and is discussed in terms of the lessons learned as a result of our high level of collaboration around design, analysis, implementation, and dissemination across projects over the past several years. Lessons learned through this partnered testing program involve respecting different time horizons among the partners, identifying relevant research questions for both parties, designing flexible studies, engaging all partners throughout the research, and placing an emphasis on relationship building at all times. These lessons and strategies can benefit others conducting partner-based research both within the Veterans Health Administration (VA) and in other integrated healthcare systems.


Assuntos
Pesquisa Participativa Baseada na Comunidade/organização & administração , Comportamento Cooperativo , Saúde Pública , Pesquisadores/organização & administração , United States Department of Veterans Affairs , Infecções por HIV/diagnóstico , Hepatite C/diagnóstico , Humanos , Estados Unidos , Saúde dos Veteranos/estatística & dados numéricos
17.
Pacing Clin Electrophysiol ; 37(9): 1149-58, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24831656

RESUMO

BACKGROUND: Organized atrial tachycardias (OATs) after pulmonary vein isolation (PVI) procedure are common. Arrhythmia mechanisms include mitral annular, ring gap, or roof-dependent gap-related flutters. In this series, we describe a mechanism of arrhythmia utilizing the ridge between left pulmonary vein (PV) and left atrial appendage (LAA) in the Ligament of Marshall (LOM) region. METHODS AND RESULTS: Five tachycardias involving the LOM region were identified from a group of 240 patients who underwent a single ring PVI procedure for symptomatic atrial fibrillation. The common characteristics of these tachycardias were the endocardial breakout over a broad area adjacent to the LOM region, presence of presystolic or mid-diastolic potentials, and abolition by ablation of the presystolic or mid-diastolic potentials remote from the endocardial breakout site. In all five cases, tachycardias were present after isolation of the veins and posterior left atria. All demonstrated characteristic areas of very slow conduction in the LOM region highlighted by presence of either low voltage, long duration fractionated potentials, or mid-diastolic potentials with a fixed temporal relationship to the subsequent endocardial activation. The pattern of activation and termination of tachycardia during ablation was consistent with an arrhythmia utilizing an electrically insulated tract within LOM and the PV-LAA ridge region. CONCLUSIONS: We identified a pattern of arrhythmias involving a concealed presystolic component and a broad endocardial breakout site related to the LOM region. Successful ablation site involved careful identification of small diastolic potentials in the LAA/ridge region or adjacent to the coronary sinus.


Assuntos
Fibrilação Atrial/cirurgia , Ablação por Cateter/métodos , Ligamentos/cirurgia , Veias Pulmonares/cirurgia , Taquicardia Supraventricular/diagnóstico , Taquicardia Supraventricular/fisiopatologia , Idoso , Técnicas Eletrofisiológicas Cardíacas , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Resultado do Tratamento
18.
Pacing Clin Electrophysiol ; 37(6): 781-90, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24697803

RESUMO

Administration of intravenous sedation (IVS) has become an integral component of procedural cardiac electrophysiology. IVS is employed in diagnostic and ablation procedures for transcutaneous treatment of cardiac arrhythmias, electrical cardioversion of arrhythmias, and the insertion of implantable electronic devices including pacemakers, defibrillators, and loop recorders. Sedation is frequently performed by nursing staff under the supervision of the proceduralist and in the absence of specialist anesthesiologists. The sedation requirements vary depending on the nature of the procedure. A wide range of sedation techniques have been reported with sedation from the near fully conscious to levels approaching that of general anesthesia. This review examines the methods employed and outcomes associated with reported sedation techniques. There is a large experience with the combination of benzodiazepines and narcotics. These drugs have a broad therapeutic range and the advantage of readily available reversal agents. More recently, the use of propofol without serious adverse events has been reported. The results provide a guide regarding the expected outcomes of these approaches. The complication rate and need for emergency assistance is low in reported series where sedation is administered by nonspecialist anesthesiology staff.


Assuntos
Anestesia Geral/métodos , Técnicas Eletrofisiológicas Cardíacas/efeitos adversos , Técnicas Eletrofisiológicas Cardíacas/métodos , Hipnóticos e Sedativos/administração & dosagem , Dor/etiologia , Dor/prevenção & controle , Humanos
19.
Pacing Clin Electrophysiol ; 37(7): 795-802, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24666010

RESUMO

BACKGROUND: The prognostic significance of a second programmed ventricular stimulation (PVS) at electrophysiology study (EPS), when the first PVS is negative for inducible ventricular tachycardia (VT), in patients following myocardial infarction (MI) is unknown. METHODS: Consecutive ST-elevation MI patients with left ventricular ejection fraction ≤ 40% following revascularization underwent early EPS. An implantable cardioverter defibrillator (ICD) was implanted for a positive (inducible monomorphic VT) but not a negative (no arrhythmia or inducible ventricular fibrillation [VF]/flutter) EPS. The combined primary end point of death or arrhythmia (sudden death, resuscitated cardiac arrest, and spontaneous VT/VF) was assessed in EPS-positive patients grouped according to if VT was induced on the first PVS application, or the second PVS application, when the first was negative. RESULTS: EPS performed a median 8 days post-MI in 290 patients was negative in 70% (n = 203) and positive in 30% (n = 87). In patients with a positive EPS, VT was induced on the first PVS in 67% (n = 58) and the second PVS, after the first was negative, in 33% (n = 29). Predischarge ICD was implanted in 79 of 87 patients with a positive EPS. Three-year primary end point occurred in 20.9 ± 5.6% and 38.3 ± 9.7% of patients with VT induced by the first and second PVS, respectively (P = 0.042) and in 6.3 ± 1.9% of electrophysiology-negative patients (P < 0.001). CONCLUSIONS: In patients with post-MI left ventricular dysfunction, VT can be induced in a significant proportion with a second PVS when negative on the first. These patients have a similar higher risk of death or arrhythmia compared to patients with VT induced on the first PVS.


Assuntos
Morte Súbita Cardíaca/etiologia , Morte Súbita Cardíaca/prevenção & controle , Desfibriladores Implantáveis , Estimulação Elétrica , Técnicas Eletrofisiológicas Cardíacas/métodos , Infarto do Miocárdio/complicações , Taquicardia Ventricular/prevenção & controle , Taquicardia Ventricular/fisiopatologia , Função Ventricular Esquerda , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/fisiopatologia , Valor Preditivo dos Testes , Estudos Prospectivos
20.
Circ Arrhythm Electrophysiol ; 6(6): 1215-21, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24141016

RESUMO

BACKGROUND: Ventricular tachycardia (VT) is a significant complication of myocardial infarction. Radiofrequency ablation for postinfarct VT is reserved for drug refractory VT or VT storms. Our hypothesis is that radiofrequency ablation in the early postinfarct period could abolish or diminish late recurrences of VT. METHODS AND RESULTS: Myocardial infarct was induced by balloon occlusion of the left anterior descending artery in 35 sheep. The 25 survivors underwent programmed ventricular stimulation and electroanatomical mapping 8 days postinfarct. Animals with inducible VT (12 out of 25 animals) underwent immediate radiofrequency ablation. Further VT inductions were performed 100 and 200 days postinfarct. At day 8, 3.0±0.9 VT morphologies per animal were inducible. All were successfully ablated with 24±6 applications of radiofrequency energy. All had ablations on the left ventricular endocardium, and 67% had ablations on the right ventricular aspect of the interventricular septum. All targeted arrhythmias were successfully ablated acutely. One animal was euthanized because of hypotension from a serious pericardial effusion. The other 11 survived and remained arrhythmia free on subsequent inductions on the 100th and 200th days (P<0.001). The 13 animals without inducible VT remained noninducible at the subsequent studies. A historical control arm of 9 animals with inducible VT at day 8 remained inducible at day 100. CONCLUSIONS: Radiofrequency ablation on the eighth day after infarction abolished inducibility of VT at late induction studies ≤200 days in an ovine model. Early identification and ablation of VT after infarction may prevent or reduce late ventricular arrhythmias but needs to be validated in clinical studies.


Assuntos
Ablação por Cateter , Taquicardia Ventricular/cirurgia , Potenciais de Ação/fisiologia , Animais , Modelos Animais de Doenças , Eletrocardiografia , Técnicas Eletrofisiológicas Cardíacas , Masculino , Infarto do Miocárdio/complicações , Prevenção Secundária , Ovinos , Taquicardia Ventricular/etiologia , Fatores de Tempo
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