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1.
Brain Inj ; : 1-9, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38967329

RESUMO

OBJECTIVE: To estimate rates and time to reach emergence of consciousness from vegetative state/unresponsive wakefulness syndrome (VS/UWS), and explore factors associated with improved recovery in children and adolescents with disorders of consciousness (DoC) following severe traumatic and non-traumatic brain injury. METHODS: Analytical, retrospective, cohort study. Clinical records of consecutively referred patients admitted in VS/UWS to a neurological rehabilitation institute in Argentina, between 2005 and 2021 were reviewed. Seventy children and adolescents were included in the analysis. A specialized 12-week rehabilitation program was administered, and emergence was defined by scores ≥44 points on the Western Neuro Sensory Stimulation Profile (WNSSP), sustained for at least 3 weeks on consecutive weekly evaluations. RESULTS: Emergence from VS/UWS to consciousness occurred within 5.4 (SD 2.6) weeks in almost one-third of patients. Multivariate Cox regression analysis showed emergence was significantly lower in patients with hypoxic ischemic encephalopathy compared to patients with other non-traumatic etiologies [HRadj 0.23 (95% CI 0.06-0.89); p = 0.03)]. CONCLUSIONS: Our findings reinforce growing evidence on the impact of etiology on DoC recovery in pediatric populations, ultimately influencing treatment and family-related decisions in child neurorehabilitation.

2.
J Electrocardiol ; 77: 58-61, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36634462

RESUMO

INTRODUCTION: Electrocardiographic Imaging is a non-invasive technique that requires cardiac Imaging for the reconstruction of cardiac electrical activity. In this study, we explored imageless ECGI by quantifying the errors of using heart meshes with either an inaccurate location inside the thorax or an inaccurate geometry. METHODS: Multiple­lead body surface recordings of 25 atrial fibrillation (AF) patients were recorded. Cardiac atrial meshes were obtained by segmentation of medical images obtained for each patient. ECGI was computed with each patient's segmented atrial mesh and compared with the ECGI obtained under errors in the atrial mesh used for ECGI estimation. We modeled both the uncertainty in the location of the atria inside the thorax by artificially translating the atria inside the thorax and the geometry of the atrial mesh by using an atrial mesh in a reference database. ECGI signals obtained with the actual meshes and the translated or estimated meshes were compared in terms of their correlation coefficients, relative difference measurement star, and errors in the dominant frequency (DF) estimation in epicardial nodes. RESULTS: CC between ECGI signals obtained after translating the actual atrial meshes from the original position by 1 cm was above 0.97. CC between ECGIs obtained with patient specific atrial geometry and estimated atrial geometries was 0.93 ± 0.11. Mean errors in DF estimation using an estimated atrial mesh were 7.6 ± 5.9%. CONCLUSION: Imageless ECGI can provide a robust estimation of cardiac electrophysiological parameters such as activation rates even during complex arrhythmias. Furthermore, it can allow more widespread use of ECGI in clinical practice.


Assuntos
Fibrilação Atrial , Eletrocardiografia , Humanos , Eletrocardiografia/métodos , Incerteza , Átrios do Coração/diagnóstico por imagem , Diagnóstico por Imagem , Mapeamento Potencial de Superfície Corporal/métodos
3.
Acta Chir Belg ; 123(3): 231-237, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34445925

RESUMO

INTRODUCTION: The need to care for patients with emergency symptoms still continues during the COVID-19 pandemic. The number of emergency surgery procedures performed in Spanish hospitals decreased significantly during the first wave of COVID-19. PATIENTS AND METHODS: We performed a retrospective cohort study comparing the emergency surgery activity in a Spanish tertiary Hospital during the COVID-19 pandemic and emergency surgery activity registered in 2019 during the equivalent time period. RESULTS: A total of 1802 patients were included in control group (CG) versus 756 in pandemic group (PG). Mean number of patients who underwent emergency surgery during the control and pandemic periods was 3.42 patients per day, in contrast to 1.62 during the pandemic period, which represents a 52.6% decrease in emergency surgery activity. During the pandemic period, most of the patients consulted after more than 72 h of symptoms, representing a delay in presenting in the ER of 23.7% when compared to CG. Surgeries due to complications from previous elective procedures decreased (12% vs. 6.1%) in PG, probably because elective procedures are being postponed. We had a 13.1% COVID-19 positivity rate. Morbidity was higher during pandemic (52.5% vs. 35.2%). Mortality rates in patients undergoing emergency surgery was higher in PG (12.1% vs. 4.8%). CONCLUSIONS: The impact of the first wave of COVID-19 in emergency surgery activity has been profound. A significant reduction in emergency surgery was observed, along with longer time periods between patients' onset of symptoms and their arrival at the Emergency Department. Higher morbidity was also observed during the pandemic period.


Assuntos
COVID-19 , Humanos , COVID-19/epidemiologia , Estudos de Coortes , Centros de Atenção Terciária , SARS-CoV-2 , Estudos Retrospectivos , Pandemias , Serviço Hospitalar de Emergência
4.
Radiologia ; 65(2): 176-179, 2023.
Artigo em Espanhol | MEDLINE | ID: mdl-35370312

RESUMO

The disease caused by Sars-Cov-2 (Covid-19) has become a worldwide pandemic and consequently a public health problem. Multiple complications associated with Covid-19 have been described, including coagulation abnormalities. Although the infection is known to induce a prothrombotic state, hemorrhagic complications have also been reported in patients with Covid-19, especially in anticoagulated patients. We present two cases of spontaneous pulmonary hematoma in patients with Covid-19 undergoing anticoagulant treatment. We aim to describe this complication, which although uncommon, should be taken into account in anticoagulated patients with Covid-19.

5.
Circ Res ; 124(6): 938-951, 2019 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-30870121

RESUMO

The myocardium consists of numerous cell types embedded in organized layers of ECM (extracellular matrix) and requires an intricate network of blood and lymphatic vessels and nerves to provide nutrients and electrical coupling to the cells. Although much of the focus has been on cardiomyocytes, these cells make up <40% of cells within a healthy adult heart. Therefore, repairing or regenerating cardiac tissue by merely reconstituting cardiomyocytes is a simplistic and ineffective approach. In fact, when an injury occurs, cardiac tissue organization is disrupted at the level of the cells, the tissue architecture, and the coordinated interaction among the cells. Thus, reconstitution of a functional tissue must reestablish electrical and mechanical communication between cardiomyocytes and restore their surrounding environment. It is also essential to restore distinctive myocardial features, such as vascular patency and pump function. In this article, we review the current status, challenges, and future priorities in cardiac regenerative or reparative medicine. In the first part, we provide an overview of our current understanding of heart repair and comment on the main contributors and mechanisms involved in innate regeneration. A brief section is dedicated to the novel concept of rejuvenation or regeneration, which we think may impact future development in the field. The last section describes regenerative therapies, where the most advanced and disruptive strategies used for myocardial repair are discussed. Our recommendations for priority areas in studies of cardiac regeneration or repair are summarized in Tables 1 and 2 .


Assuntos
Miócitos Cardíacos/fisiologia , Regeneração/fisiologia , Medicina Regenerativa , Fibroblastos/fisiologia , Humanos , Inflamação/fisiopatologia
6.
Pacing Clin Electrophysiol ; 44(3): 519-527, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33538337

RESUMO

BACKGROUND: Multipoint pacing (MPP) in cardiac resynchronization therapy (CRT) activates the left ventricle from two locations, thereby shortening the QRS duration and enabling better resynchronization; however, compared with conventional CRT, MPP reduces battery longevity. On the other hand, electrocardiogram-based optimization using the fusion-optimized intervals (FOI) method achieves more significant reverse remodeling than nominal CRT programming. Our study aimed to determine whether MPP could attain better resynchronization than single-point pacing (SPP) optimized by FOI. METHODS: This prospective study included 32 consecutive patients who successfully received CRT devices with MPP capabilities. After implantation, the QRS duration was measured during intrinsic rhythm and with three pacing configurations: MPP, SPP-FOI, and MPP-FOI. In 14 patients, biventricular activation times (by electrocardiographic imaging, ECGI) were obtained during intrinsic rhythm and for each pacing configuration to validate the findings. Device battery longevity was estimated at the 45-day follow-up. RESULTS: The SPP-FOI method achieved greater QRS shortening than MPP (-56 ± 16 vs. -42 ± 17 ms, p < .001). Adding MPP to the best FOI programming did not result in further shortening (MPP-FOI: -58 ± 14 ms, p = .69). Although biventricular activation times did not differ significantly among the three pacing configurations, only the two FOI configurations achieved significant shortening compared with intrinsic rhythm. The estimated battery longevity was longer with SPP than with MPP (8.1 ± 2.3 vs. 6.3 ± 2.0 years, p = .03). CONCLUSIONS: SPP optimized by FOI resulted in better resynchronization and longer battery duration than MPP.


Assuntos
Terapia de Ressincronização Cardíaca/métodos , Disfunção Ventricular Esquerda/terapia , Idoso , Ecocardiografia , Fontes de Energia Elétrica , Eletrocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Disfunção Ventricular Esquerda/fisiopatologia
7.
Circ Res ; 122(2): 310-318, 2018 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-29348252

RESUMO

The international consortium TACTICS (Transnational Alliance for Regenerative Therapies in Cardiovascular Syndromes) has recently addressed key priorities in the field of cell-based therapy for cardiac repair, identifying the efficacy of translational research as one of the main challenges to ultimately improve the quality of life of patients with ischemic disease. Much of the controversy and confusion surrounding cardiac regenerative therapy stems from insufficient rigor in the conduct of preclinical studies, and there is an increasing recognition of a number of problems that undermine its quality that may contribute to translational failure. Here, we introduce well defined stages for preclinical research, and put forth proposals that should promote more rigorous preclinical work, in an effort to improve its quality and translatability. To augment the utility of preclinical research and its translation, it is necessary to (1) improve the quality of preclinical research, (2) promote collaborative efforts, and (3) enhance the sharing of knowledge and protocols. In particular, confirmatory (stage III) preclinical studies should be considered as a preamble to clinical studies and therefore must adhere to their standards of quality (including internal validity, standardization of protocols, and multicenter design). To increase transparency and minimize bias, these studies should be prospectively registered in an independent, open database. Ultimately, these recommendations should be implemented in the daily routine of investigators and in the policies of institutions, journals, and funding agencies.


Assuntos
Doenças Cardiovasculares/terapia , Medicina Regenerativa/métodos , Pesquisa Translacional Biomédica/métodos , Animais , Doenças Cardiovasculares/genética , Doenças Cardiovasculares/patologia , Humanos , Metanálise como Assunto , Medicina Regenerativa/tendências , Revisões Sistemáticas como Assunto , Pesquisa Translacional Biomédica/tendências
8.
Org Biomol Chem ; 17(5): 1097-1112, 2019 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-30633297

RESUMO

The synthesis of dehydrophos derivatives featuring modified peptide chains, characterized by the presence of substituents in the vinyl moiety, or possessing a phosphonic acid monoalkyl ester other than the monomethyl ester one, has been accomplished by a versatile procedure based on Horner-Wadsworth-Emmons olefination with suitable aldehydes and on the selective hydrolysis of the dialkyl phosphonate group. Such derivatives have been tested against a series of bacterial strains, using the naturally occurring peptide, dehydrophos, for comparison. Thus, the effects of the aforementioned structural variations on antimicrobial activity have been studied.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Compostos Organofosforados/síntese química , Compostos Organofosforados/farmacologia , Peptídeos/química , Aldeídos/química , Alcenos/química , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Hidrólise , Testes de Sensibilidade Microbiana , Compostos Organofosforados/química , Conformação Proteica , Estereoisomerismo
9.
J Cardiovasc Electrophysiol ; 27(5): 563-70, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26799774

RESUMO

INTRODUCTION: The diagnosis of Brugada syndrome based on the ECG is hampered by the dynamic nature of its ECG manifestations. Brugada syndrome patients are only 25% likely to present a type 1 ECG. The objective of this study is to provide an ECG diagnostic criterion for Brugada syndrome patients that can be applied consistently even in the absence of a type 1 ECG. METHODS AND RESULTS: We recorded 67-lead body surface potential maps from 94 Brugada syndrome patients and 82 controls (including right bundle branch block patients and healthy individuals). The spatial propagation direction during the last r' wave and the slope at the end of the QRS complex were measured and compared between patients groups. Receiver-operating characteristic curves were constructed for half of the database to identify optimal cutoff values; sensitivity and specificity for these cutoff values were measured in the other half of the database. A spontaneous type 1 ECG was present in only 30% of BrS patients. An orientation in the sagittal plane < 101º during the last r' wave and a descending slope < 9.65 mV/s enables the diagnosis of the syndrome with a sensitivity of 69% and a specificity of 97% in non-type 1 Brugada syndrome patients. CONCLUSION: Spatiotemporal characteristics of surface ECG recordings can enable a robust identification of BrS even without the presence of a type 1 ECG.


Assuntos
Potenciais de Ação , Síndrome de Brugada/diagnóstico , Eletrocardiografia , Sistema de Condução Cardíaco/fisiopatologia , Frequência Cardíaca , Adulto , Área Sob a Curva , Síndrome de Brugada/fisiopatologia , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Curva ROC , Processamento de Sinais Assistido por Computador , Espanha , Fatores de Tempo
10.
J Cardiovasc Electrophysiol ; 27(4): 435-42, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26776725

RESUMO

INTRODUCTION: Ablation of high dominant frequency (DF) sources in patients with atrial fibrillation (AF) is an effective treatment option for paroxysmal AF. The aim of this study was to evaluate the accuracy of noninvasive estimation of DF and electrical patterns determination by solving the inverse problem of the electrocardiography. METHODS: Four representative AF patients with left-to-right and right-to-left atrial DF patterns were included in the study. For each patient, intracardiac electrograms from both atria were recorded simultaneously together with 67-lead body surface recordings. In addition to clinical recordings, realistic mathematical models of atria and torso anatomy with different DF patterns of AF were used. For both mathematical models and clinical recordings, inverse-computed electrograms were compared to intracardiac electrograms in terms of voltage, phase, and frequency spectrum relative errors. RESULTS: Comparison between intracardiac and inverse computed electrograms for AF patients showed 8.8 ± 4.4% errors for DF, 32 ± 4% for voltage, and 65 ± 4% for phase determination. These results were corroborated by mathematical simulations showing that the inverse problem solution was able to reconstruct the frequency spectrum and the DF maps with relative errors of 5.5 ± 4.1%, whereas the reconstruction of the electrograms or the instantaneous phase presented larger relative errors (i.e., 38 ± 15% and 48 ± 14 % respectively, P < 0.01). CONCLUSIONS: Noninvasive reconstruction of atrial frequency maps can be achieved by solving the inverse problem of electrocardiography with a higher accuracy than temporal distribution patterns.


Assuntos
Fibrilação Atrial/diagnóstico , Fibrilação Atrial/fisiopatologia , Mapeamento Potencial de Superfície Corporal/métodos , Mapeamento Epicárdico/métodos , Modelos Cardiovasculares , Pericárdio/fisiopatologia , Algoritmos , Simulação por Computador , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
11.
Am J Physiol Heart Circ Physiol ; 309(11): H1964-73, 2015 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-26408535

RESUMO

The objective of this article is to present an in vitro model of atrial cardiac tissue that could serve to study the mechanisms of remodeling related to atrial fibrillation (AF). We analyze the modification on gene expression and modifications on rotor dynamics following tissue remodeling. Atrial murine cells (HL-1 myocytes) were maintained in culture after the spontaneous initiation of AF and analyzed at two time points: 3.1 ± 1.3 and 9.7 ± 0.5 days after AF initiation. The degree of electrophysiological remodeling (i.e., relative gene expression of key ion channels) and structural inhomogeneity was compared between early and late cell culture times both in nonfibrillating and fibrillating cell cultures. In addition, the electrophysiological characteristics of in vitro fibrillation [e.g., density of phase singularities (PS/cm(2)), dominant frequency, and rotor meandering] analyzed by means of optical mapping were compared with the degree of electrophysiological remodeling. Fibrillating cell cultures showed a differential ion channel gene expression associated with atrial tissue remodeling (i.e., decreased SCN5A, CACN1C, KCND3, and GJA1 and increased KCNJ2) not present in nonfibrillating cell cultures. Also, fibrillatory complexity was increased in late- vs. early stage cultures (1.12 ± 0.14 vs. 0.43 ± 0.19 PS/cm(2), P < 0.01), which was associated with changes in the electrical reentrant patterns (i.e., decrease in rotor tip meandering and increase in wavefront curvature). HL-1 cells can reproduce AF features such as electrophysiological remodeling and an increased complexity of the electrophysiological behavior associated with the fibrillation time that resembles those occurring in patients with chronic AF.


Assuntos
Fibrilação Atrial/fisiopatologia , Remodelamento Atrial , Potenciais de Ação , Animais , Antiarrítmicos/farmacologia , Fibrilação Atrial/tratamento farmacológico , Fibrilação Atrial/genética , Fibrilação Atrial/metabolismo , Remodelamento Atrial/efeitos dos fármacos , Canais de Cálcio Tipo L/genética , Canais de Cálcio Tipo L/metabolismo , Linhagem Celular , Conexina 43/genética , Conexina 43/metabolismo , Regulação da Expressão Gênica , Átrios do Coração/efeitos dos fármacos , Átrios do Coração/metabolismo , Átrios do Coração/fisiopatologia , Camundongos , Modelos Cardiovasculares , Canal de Sódio Disparado por Voltagem NAV1.5/genética , Canal de Sódio Disparado por Voltagem NAV1.5/metabolismo , Canais de Potássio Corretores do Fluxo de Internalização/genética , Canais de Potássio Corretores do Fluxo de Internalização/metabolismo , Canais de Potássio Shal/genética , Canais de Potássio Shal/metabolismo , Fatores de Tempo , Imagens com Corantes Sensíveis à Voltagem
13.
Br J Cancer ; 110(5): 1334-7, 2014 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-24496455

RESUMO

BACKGROUND: We aimed to evaluate whether oral anticoagulants (OACs) alter faecal immunochemical test (FIT) performance in average-risk colorectal cancer (CRC) screening. METHODS: Individuals aged 50-69 years were invited to receive one FIT sample (cutoff 75 ng ml(-1)) between November 2008 and June 2011. RESULTS: Faecal immunochemical test was positive in 9.3% (21 out of 224) of users of OAC and 6.2% (365 out of 5821) of non-users (P-trend=0.07). The positive predictive value (PPV) for advanced neoplasia (AN) in non-users was 50.4% vs 47.6% in users (odds ratio, 0.70; 95% CI, 0.3-1.8; P=0.5). The PPV for AN in OAC more antiplatelets (aspirin or clopidogrel) was 75% (odds ratio, 2; 95% CI, 0.4-10.8; P=0.4). CONCLUSIONS: Oral anticoagulant did not significantly modify the PPV for AN in this population-based colorectal screening program. The detection rate of advanced adenoma was higher in the combination OAC more antiplatelets.


Assuntos
Anticoagulantes/administração & dosagem , Neoplasias Colorretais/diagnóstico , Sangue Oculto , Colonoscopia/métodos , Neoplasias Colorretais/prevenção & controle , Detecção Precoce de Câncer/métodos , Feminino , Humanos , Imunoquímica/métodos , Masculino , Programas de Rastreamento/métodos , Pessoa de Meia-Idade
14.
Hum Genet ; 133(5): 525-34, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24218287

RESUMO

Colorectal cancer (CRC) is a complex disease, and therefore its development is determined by the combination of both environmental factors and genetic variants. Although genome-wide association studies (GWAS) of SNP variation have conveniently identified 20 genetic variants so far, a significant proportion of the observed heritability is yet to be explained. Common copy-number variants (CNVs) are one of the most important genomic sources of variability, and hence a potential source to explain part of this missing genetic fraction. Therefore, we have performed a GWAS on CNVs to explore the relationship between common structural variation and CRC development. Phase 1 of the GWAS consisted of 881 cases and 667 controls from a Spanish cohort. Copy-number status was validated by quantitative PCR for each of those common CNVs potentially associated with CRC in phase I. Subsequently, SNPs were chosen as proxies for the validated CNVs for phase II replication (1,342 Spanish cases and 1,874 Spanish controls). Four common CNVs were found to be associated with CRC and were further replicated in Phase II. Finally, we found that SNP rs1944682, tagging a 11q11 CNV, was nominally associated with CRC susceptibility (p value = 0.039; OR = 1.122). This locus has been previously related to extreme obesity phenotypes, which could suggest a relationship between body weight and CRC susceptibility.


Assuntos
Cromossomos Humanos Par 11 , Neoplasias Colorretais/genética , Dosagem de Genes , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Polimorfismo de Nucleotídeo Único
16.
Med Intensiva ; 38(3): 133-9, 2014 Apr.
Artigo em Espanhol | MEDLINE | ID: mdl-23473519

RESUMO

OBJECTIVE: To determine whether there are differences between subglottic pressure during swallowing with and without air insufflation via a subglottic catheter in tracheostomized patients. DESIGN: A prospective, randomized cross-over study was made. SETTING: Adult Intensive Care Units. PARTICIPANTS: Patients requiring mechanical ventilation and tracheostomy with a subglottic catheter, and with tolerance to deflation of the balloon and a speaking valve placed over the opening of the tracheostomy tube. INTERVENTIONS: Subglottic pressure was measured during swallowing of a thickened solution with and without the delivery of airflow through the subglottic catheter. MAIN VARIABLE: Subglottic pressure during swallowing. RESULTS: Twelve out of 14 patients showed higher subglottic pressure values during swallowing with air insufflation. Two patients showed no differences between both conditions. Median (Med) values of subglottic pressure for the first, second and third swallow were 5, 4 and 4.5 cmH2O (Med 4.5 cmH2O) without air insufflation, and 8, 5.5 and 7.5 cmH2O (Med 5.5 cmH2O) with air insufflation, respectively (Wilcoxon, Z=-3.078; p=.002). CONCLUSION: In a group of tracheostomized patients, air insufflation via a subglottic catheter increased subglottic pressure levels measured during swallowing.


Assuntos
Ar , Deglutição/fisiologia , Adulto , Idoso , Cateterismo , Estudos Cross-Over , Transtornos de Deglutição/etiologia , Transtornos de Deglutição/fisiopatologia , Nutrição Enteral , Feminino , Humanos , Insuflação , Masculino , Pessoa de Meia-Idade , Pressão , Estudos Prospectivos , Respiração , Respiração Artificial , Reologia , Soluções , Traqueostomia , Viscosidade , Adulto Jovem
17.
Comput Methods Programs Biomed ; 246: 108052, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38350188

RESUMO

BACKGROUND AND OBJECTIVE: Atrial Fibrillation (AF) is a supraventricular tachyarrhythmia that can lead to thromboembolism, hearlt failure, ischemic stroke, and a decreased quality of life. Characterizing the locations where the mechanisms of AF are initialized and maintained is key to accomplishing an effective ablation of the targets, hence restoring sinus rhythm. Many methods have been investigated to locate such targets in a non-invasive way, such as Electrocardiographic Imaging, which enables an on-invasive and panoramic characterization of cardiac electrical activity using recording Body Surface Potentials (BSP) and a torso model of the patient. Nonetheless, this technique entails some major issues stemming from solving the inverse problem, which is known to be severely ill-posed. In this context, many machine learning and deep learning approaches aim to tackle the characterization and classification of AF targets to improve AF diagnosis and treatment. METHODS: In this work, we propose a method to locate AF drivers as a supervised classification problem. We employed a hybrid form of the convolutional-recurrent network which enables feature extraction and sequential data modeling utilizing labeled realistic computerized AF models. Thus, we used 16 AF electrograms, 1 atrium, and 10 torso geometries to compute the forward problem. Previously, the AF models were labeled by assigning each sample of the signals a region from the atria from 0 (no driver) to 7, according to the spatial location of the AF driver. The resulting 160 BSP signals, which resemble a 64-lead vest recording, are preprocessed and then introduced into the network following a 4-fold cross-validation in batches of 50 samples. RESULTS: The results show a mean accuracy of 74.75% among the 4 folds, with a better performance in detecting sinus rhythm, and drivers near the left superior pulmonary vein (R1), and right superior pulmonary vein (R3) whose mean sensitivity bounds around 84%-87%. Significantly good results are obtained in mean sensitivity (87%) and specificity (83%) in R1. CONCLUSIONS: Good results in R1 are highly convenient since AF drivers are commonly found in this area: the left atrial appendage, as suggested in some previous studies. These promising results indicate that using CNN-LSTM networks could lead to new strategies exploiting temporal correlations to address this challenge effectively.


Assuntos
Fibrilação Atrial , Ablação por Cateter , Humanos , Fibrilação Atrial/diagnóstico , Qualidade de Vida , Memória de Curto Prazo , Átrios do Coração/cirurgia , Redes Neurais de Computação , Ablação por Cateter/métodos
18.
Heart Rhythm ; 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38636930

RESUMO

BACKGROUND: Atrial arrhythmogenic substrate is a key determinant of atrial fibrillation (AF) recurrence after pulmonary vein isolation (PVI), and reduced conduction velocities have been linked to adverse outcome. However, a noninvasive method to assess such electrophysiologic substrate is not available to date. OBJECTIVE: This study aimed to noninvasively assess regional conduction velocities and their association with arrhythmia-free survival after PVI. METHODS: A consecutive 52 patients scheduled for AF ablation (PVI only) and 19 healthy controls were prospectively included and received electrocardiographic imaging (ECGi) to noninvasively determine regional atrial conduction velocities in sinus rhythm. A novel ECGi technology obviating the need of additional computed tomography or cardiac magnetic resonance imaging was applied and validated by invasive mapping. RESULTS: Mean ECGi-determined atrial conduction velocities were significantly lower in AF patients than in healthy controls (1.45 ± 0.15 m/s vs 1.64 ± 0.15 m/s; P < .0001). Differences were particularly pronounced in a regional analysis considering only the segment with the lowest average conduction velocity in each patient (0.8 ± 0.22 m/s vs 1.08 ± 0.26 m/s; P < .0001). This average conduction velocity of the "slowest" segment was independently associated with arrhythmia recurrence and better discriminated between PVI responders and nonresponders than previously proposed predictors, including left atrial size and late gadolinium enhancement (magnetic resonance imaging). Patients without slow-conduction areas (mean conduction velocity <0.78 m/s) showed significantly higher 12-month arrhythmia-free survival than those with 1 or more slow-conduction areas (88.9% vs 48.0%; P = .002). CONCLUSION: This is the first study to investigate regional atrial conduction velocities noninvasively. The absence of ECGi-determined slow-conduction areas well discriminates PVI responders from nonresponders. Such noninvasive assessment of electrical arrhythmogenic substrate may guide treatment strategies and be a step toward personalized AF therapy.

19.
Pharmacogenomics J ; 13(3): 209-17, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22310351

RESUMO

The development of genotyping technologies has allowed for wider screening for inherited causes of variable outcomes following drug administration. We have performed a genome-wide association study (GWAS) on 221 colorectal cancer (CRC) patients that had been treated with 5-fluorouracil (5-FU), either alone or in combination with oxaliplatin (FOLFOX). A validation set of 791 patients was also studied. Seven SNPs (rs16857540, rs2465403, rs10876844, rs10784749, rs17626122, rs7325568 and rs4243761) showed evidence of association (pooled P-values 0.020, 9.426E-03, 0.010, 0.017, 0.042, 2.302E-04, 2.803E-03) with adverse drug reactions (ADRs). This is the first study to explore the genetic basis of inter-individual variation in toxicity responses to the administration of 5-FU or FOLFOX in CRC patients on a genome-wide scale.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Fluoruracila/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Farmacológicos , Ensaios Clínicos Fase II como Assunto , Neoplasias Colorretais/patologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/genética , Feminino , Estudo de Associação Genômica Ampla , Técnicas de Genotipagem , Humanos , Leucovorina/administração & dosagem , Masculino , Pessoa de Meia-Idade , Compostos Organoplatínicos/administração & dosagem , Farmacogenética , Polimorfismo de Nucleotídeo Único/genética , Resultado do Tratamento
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