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1.
Artigo em Japonês | MEDLINE | ID: mdl-31956184

RESUMO

PURPOSE: The International Commission on Radiological Protection recommended that interventional radiologies (IRs) have high radiation doses and that staff may also be exposed to high doses. In the present study, we measured the radiation exposure dose [3 mm dose equivalent, Hp (3) ] in the eye using an appropriate dosimeter placed next to the physician' s eye during neurovascular intervention procedure (Neuro-IR) and interventional cardiac electrophysiology procedure (EP-IR). METHOD: Physicians wore a direct eye dosemeter just lateral to the left eye and an additional direct eye dosemeter outside the radiation protective glasses close to their left eye. Additionally, a neck badge [0.07 mm dose equivalent, Hp (0.07) ] was worn outside the protective apron to the left of the neck, to compare the direct eye dosimeter estimated doses. The occupational eye lens dose was evaluated over a period of 6-month. RESULTS: The maximum Hp (3) of the Neuro-IR physician was estimated 5.1 mSv without the radiation protective glasses and 1.6 mSv with the radiation protective glasses. On the other hand, the maximum Hp (3) of the EP-IR physician was estimated 29 mSv without the radiation protective glasses and 15 mSv with the radiation protective glasses. CONCLUSION: Physicians eye lens dose [Hp (3) ] tended to be overestimated by the neck badge measurements [Hp (0.07)]. A correct evaluation of the lens dose [Hp (3) ] using the direct eye dosimeter is recommended. Although we found a positive correlation between Hp (0.07) and Hp (3), the value of R2 in the regression equation is low, we recommended that the eye lens dose estimated carefully from Hp (0.07).


Assuntos
Técnicas Eletrofisiológicas Cardíacas , Cristalino , Exposição Ocupacional , Exposição à Radiação , Proteção Radiológica , Humanos , Cristalino/efeitos da radiação , Exposição Ocupacional/prevenção & controle , Doses de Radiação , Radiologia Intervencionista
2.
Int Heart J ; 61(1): 174-177, 2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-31956137

RESUMO

An 18-year-old male who had a past medical history of an intracardiac total cavopulmonary connection (TCPC) operation was referred to our hospital for radiofrequency catheter ablation (RFCA) of supraventricular tachycardia (SVT). Two types of SVTs were induced, and 3-dimensional (3D) maps were created using an ultra-high-density 3-dimensional mapping system (Rhythmia). The earliest atrial activation site (EAAS) of SVT1 was at the superior part of the conduit, and the EAAS of SVT2 was at the inferior part of the single atrium (SA). The SVTs were terminated by energy deliveries to the EAAS from the conduit in SVT1 and from inside the single atrium in SVT2. Detailed maps of the SVTs were important to understand the mechanisms of the SVTs. The Rhythmia system was useful for the detailed mapping of complex arrhythmias. The use of Rhythmia in patients after a TCPC is difficult, because puncturing the TCPC conduit and proceeding and manipulating the Orion catheter via a narrow puncture hole are difficult. We were the first to succeed in ablating two atrial tachycardias (ATs) originating from the inside and outside of the conduit after a TCPC operation by using an ultra-high-density 3-dimensional mapping system.


Assuntos
Técnica de Fontan/efeitos adversos , Taquicardia Atrial Ectópica/cirurgia , Taquicardia Supraventricular/cirurgia , Adolescente , Ablação por Cateter , Técnicas Eletrofisiológicas Cardíacas , Humanos , Masculino , Tomografia Computadorizada por Raios X
3.
Rev Esp Cardiol (Engl Ed) ; 72(12): 1031-1042, 2019 Dec.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-31732435

RESUMO

INTRODUCTION AND OBJECTIVES: This report presents the findings of the 2018 Spanish Catheter Ablation Registry. METHODS: Data collection was retrospective. A standardized questionnaire was completed by each of the participating centers. RESULTS: Data sent by 100 centers were analyzed, with a total number of 16566 ablation procedures performed (the highest historically reported in this registry) for a mean of 165.5±127.9 and a median of 119 procedures per center. The ablation targets most frequently treated were atrial fibrillation (n=4234; 25.6%), atrioventricular nodal re-entrant tachycardia (n=3525; 21.3%) and cavotricuspid isthmus (n=3425; 20.7%). A new peak was observed in the ablation of atrial fibrillation, increasing the distance from the other substrates. The overall success rate was 91%. The rate of major complications was 2.2%, and the mortality rate was 0.04%. A total of 2.1% of the ablations were performed in pediatric patients. CONCLUSIONS: The Spanish Catheter Ablation Registry enrolls systematically and continuously enrolls the ablation procedures performed in Spain, showing a progressive increasing in the number of ablations over the years, with a high success rate and low percentage of complications.


Assuntos
Arritmias Cardíacas/cirurgia , Cardiologia , Ablação por Cateter/estatística & dados numéricos , Técnicas Eletrofisiológicas Cardíacas/métodos , Sistema de Registros/estatística & dados numéricos , Sociedades Médicas , Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/fisiopatologia , Coleta de Dados , Feminino , Humanos , Masculino , Estudos Retrospectivos , Espanha
4.
Life Sci ; 239: 117053, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31733316

RESUMO

AIMS: Intracardiac injection of recombinant EphrinA1-Fc immediately following coronary artery ligation in mice reduces infarct size in both reperfused and non-reperfused myocardium, but the cellular alterations behind this phenomenon remain unknown. MAIN METHODS: Herein, 10 wk-old B6129SF2/J male mice were exposed to acute ischemia/reperfusion (30minI/24hrsR) injury immediately followed by intracardiac injection of either EphrinA1-Fc or IgG-Fc. After 24 h of reperfusion, sections of the infarct margin in the left ventricle were imaged via transmission electron microscopy, and mitochondrial function was assessed in both permeabilized fibers and isolated mitochondria, to examine mitochondrial structure, function, and energetics in the early stages of repair. KEY FINDINGS: At a structural level, EphrinA1-Fc administration prevented the I/R-induced loss of sarcomere alignment and mitochondrial organization along the Z disks, as well as disorganization of the cristae and loss of inter-mitochondrial junctions. With respect to bioenergetics, loss of respiratory function induced by I/R was prevented by EphrinA1-Fc. Preservation of cardiac bioenergetics was not due to changes in mitochondrial JH2O2 emitting potential, membrane potential, ADP affinity, efficiency of ATP production, or activity of the main dehydrogenase enzymes, suggesting that EphrinA1-Fc indirectly maintains respiratory function via preservation of the mitochondrial network. Moreover, these protective effects were lost in isolated mitochondria, further emphasizing the importance of the intact cardiomyocyte ultrastructure in mitochondrial energetics. SIGNIFICANCE: Collectively, these data suggest that intracardiac injection of EphrinA1-Fc protects cardiac function by preserving cardiomyocyte structure and mitochondrial bioenergetics, thus emerging as a potential therapeutic strategy in I/R injury.


Assuntos
Efrina-A1/farmacologia , Mitocôndrias Cardíacas/efeitos dos fármacos , Traumatismo por Reperfusão/tratamento farmacológico , Animais , Modelos Animais de Doenças , Técnicas Eletrofisiológicas Cardíacas/métodos , Metabolismo Energético , Efrina-A1/administração & dosagem , Masculino , Camundongos , Camundongos Endogâmicos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Infarto do Miocárdio/metabolismo , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo
6.
PLoS One ; 14(7): e0217988, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31269029

RESUMO

BACKGROUND: Specific tools have been recently developed to map atrial fibrillation (AF) and help guide ablation. However, when used in clinical practice, panoramic AF maps generated from multipolar intracardiac electrograms have yielded conflicting results between centers, likely due to their complexity and steep learning curve, thus limiting the proper assessment of its clinical impact. OBJECTIVES: The main purpose of this trial was to assess the impact of online training on the identification of AF driver sites where ablation terminated persistent AF, through a standardized training program. Extending this concept to mobile health was defined as a secondary objective. METHODS: An online database of panoramic AF movies was generated from a multicenter registry of patients in whom targeted ablation terminated non-paroxysmal AF, using a freely available method (Kuklik et al-method A) and a commercial one (RhythmView-method B). Cardiology Fellows naive to AF mapping were enrolled and randomized to training vs no training (control). All participants evaluated an initial set of movies to identify sites of AF termination. Participants randomized to training evaluated a second set of movies in which they received feedback on their answers. Both groups re-evaluated the initial set to assess the impact of training. This concept was then migrated to a smartphone application (App). RESULTS: 12 individuals (median age of 30 years (IQR 28-32), 6 females) read 480 AF maps. Baseline identification of AF termination sites by ablation was poor (40%±12% vs 42%±11%, P = 0.78), but similar for both mapping methods (P = 0.68). Training improved accuracy for both methods A (P = 0.001) and B (p = 0.012); whereas controls showed no change in accuracy (P = NS). The Smartphone App accessed AF maps from multiple systems on the cloud to recreate this training environment. CONCLUSION: Digital online training improved interpretation of panoramic AF maps in previously inexperienced clinicians. Combining online clinical data, smartphone apps and other digital resources provides a powerful, scalable approach for training in novel techniques in electrophysiology.


Assuntos
Fibrilação Atrial , Eletrofisiologia Cardíaca , Ablação por Cateter , Educação Médica Continuada , Técnicas Eletrofisiológicas Cardíacas , Aplicativos Móveis , Sistema de Registros , Smartphone , Gravação em Vídeo , Adulto , Idoso , Fibrilação Atrial/fisiopatologia , Fibrilação Atrial/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
7.
PLoS One ; 14(6): e0217282, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31242221

RESUMO

BACKGROUND: In previous pilot work we demonstrated that a novel automated signal analysis tool could accurately identify successful ablation sites during Wolff-Parkinson-White (WPW) ablation at a single center. OBJECTIVE: We sought to validate and refine this signal analysis tool in a larger multi-center cohort of children with WPW. METHODS: A retrospective review was performed of signal data from children with WPW who underwent ablation at two pediatric arrhythmia centers from 2008-2015. All patients with WPW ≤ 21 years who underwent invasive electrophysiology study and ablation with ablation signals available for review were included. Signals were excluded if temperature or power delivery was inadequate or lesion time was < 5 seconds. Ablation lesions were reviewed for each patient. Signals were classified as successful if there was loss of antegrade and retrograde accessory pathway (AP) conduction or unsuccessful if ablation did not eliminate AP conduction. Custom signal analysis software analyzed intracardiac electrograms for amplitudes, high and low frequency components, integrated area, and signal timing components to create a signal score. We validated the previously published signal score threshold 3.1 in this larger, more diverse cohort and explored additional scoring options. Logistic regression with lasso regularization using Youden's index criterion and a cost-benefit criterion to identify thresholds was considered as a refinement to this score. RESULTS: 347 signals (141 successful, 206 unsuccessful) in 144 pts were analyzed [mean age 13.2 ± 3.9 years, 96 (67%) male, 66 (45%) left sided APs]. The software correctly identified the signals as successful or unsuccessful in 276/347 (80%) at a threshold of 3.1. The performance of other thresholds did not significantly improve the predictive ability. A signal score threshold of 3.1 provided the following diagnostic accuracy for distinguishing a successful from unsuccessful signal: sensitivity 83%, specificity 77%, PPV 71%, NPV 87%. CONCLUSIONS: An automated signal analysis software tool reliably distinguished successful versus unsuccessful ablation electrograms in children with WPW when validated in a large, diverse cohort. Refining the tools using an alternative threshold and statistical method did not improve the original signal score at a threshold of 3.1. This software was effective across two centers and multiple operators and may be an effective tool for ablation of WPW.


Assuntos
Técnicas Eletrofisiológicas Cardíacas , Processamento de Sinais Assistido por Computador , Software , Síndrome de Wolff-Parkinson-White , Adolescente , Criança , Feminino , Humanos , Masculino , Projetos Piloto , Valor Preditivo dos Testes , Estudos Retrospectivos , Síndrome de Wolff-Parkinson-White/fisiopatologia , Síndrome de Wolff-Parkinson-White/cirurgia
8.
Am J Cardiol ; 124(3): 389-395, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31204032

RESUMO

The rising utilization of screening electrocardiograms has resulted in increased incidental identification of ventricular pre-excitation in pediatric patients. We compared accessory pathways of incidentally identified pre-excitation to Wolff-Parkinson-White Syndrome (WPW) with the aim to identify factors important in preprocedural counseling and planning. This single-center, retrospective study of patients ≤18 years without congenital heart disease identified 227 patients diagnosed with pre-excitation and referred for invasive electrophysiology study between 2008 and 2017. WPW Syndrome was diagnosed in 178 patients, while 49 patients had incidental identification of pre-excitation. Anterograde conduction of incidentally identified accessory pathways was not clinically different between the two cohorts at baseline or upon isoproterenol infusion. However, the proportion of accessory pathways meeting high-risk criteria was significantly lower than in patients diagnosed with WPW, 12% versus 28% (p < 0.05). Retrograde conduction at baseline of incidentally diagnosed accessory pathways was slower with a median block cycle length 365 milliseconds (IQR 260 to 450) versus 290 milliseconds (IQR 260 to 330, p < 0.01). In the incidentally identified cohort, right-sided, paraHisian, and fascicular pathways were more common with fewer attempted ablations (71% vs 94%, p < 0.001) and lower success rate (91% vs 97%, p < 0.001). A binomial logistic regression analysis further indicated patients incidentally identified with pre-excitation were associated with having lower rates of inducible supraventricular tachycardia, atrial fibrillation, and ablations performed, in addition, to having right-sided pathways. In conclusion, as patients with incidentally identified pre-excitation present more frequently for consideration of invasive electrophysiology study, these results impact procedural approaches, technical considerations, patient counseling, and outcome expectations.


Assuntos
Feixe Acessório Atrioventricular/diagnóstico , Técnicas Eletrofisiológicas Cardíacas , Síndromes de Pré-Excitação/fisiopatologia , Síndrome de Wolff-Parkinson-White/fisiopatologia , Feixe Acessório Atrioventricular/fisiopatologia , Feixe Acessório Atrioventricular/cirurgia , Ablação por Cateter , Criança , Pré-Escolar , Eletrocardiografia , Feminino , Humanos , Achados Incidentais , Masculino , Síndromes de Pré-Excitação/diagnóstico , Síndromes de Pré-Excitação/cirurgia , Estudos Retrospectivos , Síndrome de Wolff-Parkinson-White/diagnóstico , Síndrome de Wolff-Parkinson-White/cirurgia
9.
J Interv Card Electrophysiol ; 55(2): 233-237, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31177353

RESUMO

PURPOSE: Cardiologists are among the health professionals that are most exposed to ionizing radiation, but there is no study comparing the level of exposure of physicians during different electrophysiology procedures. We aimed to measure and compare cardiologists' exposure to radiation during different electrophysiology procedures. METHODS: The study population comprised all electrophysiology procedures performed over a 6-month period in a large referral centre. The endpoint was operator radiation exposure, assessed using a personal electronic dosimeter located on the operator's left arm. RESULTS: In total, 150 electrophysiology procedures were analyzed. Compared with electrophysiology studies (reference category), physician radiation exposure was 3-fold greater during ablation of atrial fibrillation, 9-fold greater during ablation of atrioventricular nodal reentrant tachycardia (AVNRT)/atrioventricular reentrant tachycardia (AVNT), and 10-fold greater during ablation of atrial flutter (p < 0.001). Physician exposure was mainly related to X-ray time (R2 = 0.28). CONCLUSIONS: Our study showed significant differences in cardiologists' exposure to ionizing radiation depending on the type of electrophysiology procedure. Atrial flutter and AVNRT/AVNT ablations are the procedures in which operators are most exposed to ionizing radiation.


Assuntos
Cardiologistas , Técnicas Eletrofisiológicas Cardíacas , Exposição Ocupacional , Exposição à Radiação , França , Humanos , Radiometria , Fatores de Risco
11.
Cardiol Young ; 29(5): 643-648, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31104644

RESUMO

BACKGROUND: To assess the effectiveness of radiofrequency catheter ablation for lone atrial fibrillation in young adults. METHODS: This single-centre, retrospective, observational study enrolled 75 consecutive patients (86.7% men) under 35 (median, 30) years old with lone atrial fibrillation (68% paroxysmal, 26.7% persistent, and 5.3% long-standing persistent) without other cardiopulmonary diseases who underwent catheter ablation between April 2009 and May 2017. Procedural endpoints were circumferential pulmonary vein ablation for atrial fibrillation with pulmonary vein trigger, and target ablation or bidirectional block of lines and disappearance of complex fractionated atrial electrograms for atrial fibrillation with clear and unclear non-pulmonary vein triggers, respectively. RESULTS: Main study outcome was rate of survival free from atrial tachyarrhythmia recurrence, which at median 61 (range, 5-102) months follow-up was 62.7% (64.7 and 58.3% for paroxysmal and non-paroxysmal atrial fibrillation, respectively) after single ablation, and 69.3% (68.6 and 70.8% for paroxysmal and non-paroxysmal atrial fibrillation, respectively) after mean 1.2 ablations (two and three ablations in 11 and 2 patients, respectively). In multivariate analysis, non-pulmonary vein trigger was a significant independent predictor of recurrent atrial tachyarrhythmia (OR, 10.60 [95%CI, 2.25-49.96]; p = 0.003). There were no major periprocedural adverse events. CONCLUSIONS: In patients under 35 years old with lone atrial fibrillation, radiofrequency catheter ablation appeared effective particularly for atrial fibrillation with pulmonary vein trigger and regardless of left atrial size or atrial fibrillation duration or type. Atrial tachyarrhythmia recurrence after multiple ablations warrants further study.


Assuntos
Fibrilação Atrial/cirurgia , Ablação por Cateter , Veias Pulmonares/cirurgia , Adulto , Ablação por Cateter/efeitos adversos , China , Técnicas Eletrofisiológicas Cardíacas , Feminino , Humanos , Estimativa de Kaplan-Meier , Modelos Logísticos , Masculino , Análise Multivariada , Recidiva , Estudos Retrospectivos , Taquicardia/etiologia , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
12.
Comput Methods Programs Biomed ; 175: 163-178, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31104705

RESUMO

BACKGROUND AND OBJECTIVE: Complex fractionated atrial electrograms (CFAE) may contain information concerning the electrophysiological substrate of atrial fibrillation (AF); therefore they are of interest to guide catheter ablation treatment of AF. Electrogram signals are shaped by activation events, which are dynamical in nature. This makes it difficult to establish those signal properties that can provide insight into the ablation site location. Nonlinear measures may improve information. To test this hypothesis, we used nonlinear measures to analyze CFAE. METHODS: CFAE from several atrial sites, recorded for a duration of 16 s, were acquired from 10 patients with persistent and 9 patients with paroxysmal AF. These signals were appraised using non-overlapping windows of 1-, 2- and 4-s durations. The resulting data sets were analyzed with Recurrence Plots (RP) and Recurrence Quantification Analysis (RQA). The data was also quantified via entropy measures. RESULTS: RQA exhibited unique plots for persistent versus paroxysmal AF. Similar patterns were observed to be repeated throughout the RPs. Trends were consistent for signal segments of 1 and 2 s as well as 4 s in duration. This was suggestive that the underlying signal generation process is also repetitive, and that repetitiveness can be detected even in 1-s sequences. The results also showed that most entropy metrics exhibited higher measurement values (closer to equilibrium) for persistent AF data. It was also found that Determinism (DET), Trapping Time (TT), and Modified Multiscale Entropy (MMSE), extracted from signals that were acquired from locations at the posterior atrial free wall, are highly discriminative of persistent versus paroxysmal AF data. CONCLUSIONS: Short data sequences are sufficient to provide information to discern persistent versus paroxysmal AF data with a significant difference, and can be useful to detect repeating patterns of atrial activation.


Assuntos
Fibrilação Atrial/diagnóstico , Ablação por Cateter , Técnicas Eletrofisiológicas Cardíacas , Processamento de Imagem Assistida por Computador/métodos , Algoritmos , Interpretação Estatística de Dados , Lógica Fuzzy , Humanos , Dinâmica não Linear , Processamento de Sinais Assistido por Computador
13.
Int Heart J ; 60(3): 756-760, 2019 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31105156

RESUMO

We report a case of atypical fast-slow atrioventricular nodal reentrant tachycardia (AVNRT) using a slow pathway variant extending to the superoanterior right atrium. The AVNRT diagnosis was confirmed by using standard electrophysiological criteria that exclude a diagnosis of atrial tachycardia and atrioventricular reentrant tachycardia. The earliest atrial activation during tachycardia was found in the superoanterior right atrium adjacent to the tricuspid annulus, where the first delivery of radiofrequency energy terminated and eliminated the inducibility of the tachycardia.


Assuntos
Ablação por Cateter/métodos , Técnicas Eletrofisiológicas Cardíacas/métodos , Taquicardia por Reentrada no Nó Atrioventricular/diagnóstico , Trifosfato de Adenosina/administração & dosagem , Trifosfato de Adenosina/uso terapêutico , Assistência ao Convalescente , Idoso de 80 Anos ou mais , Diagnóstico Diferencial , Eletrocardiografia , Feminino , Átrios do Coração/fisiopatologia , Humanos , Taquicardia por Reentrada no Nó Atrioventricular/fisiopatologia , Taquicardia por Reentrada no Nó Atrioventricular/terapia , Taquicardia Supraventricular/diagnóstico , Taquicardia Supraventricular/tratamento farmacológico , Resultado do Tratamento
14.
Circ Arrhythm Electrophysiol ; 12(6): e007415, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31113233

RESUMO

Background His-bundle pacing (HBP) is a physiological form of pacing. Although high capture thresholds are common, few predictors of low HBP threshold have been determined. We aimed to identify electrophysiological predictors. Methods Fifty-one patients (53% with atrioventricular block) underwent HBP for bradycardia with an intrinsic QRS duration of <120 ms. Attempts to anchor the HBP lead were guided by unipolar His-bundle electrograms (HB EGMs) recorded with an electrophysiology recording system. Patients were followed-up for >6 months. Results In total, 153 attempts at anchoring the HBP lead were made, of which, 45 achieved acceptable HBP thresholds (≤2.5 V at 1 ms). The amplitude of negative deflection in HB EGM and the selective HBP form at fixation were independently associated with achieving an acceptable threshold. A negative amplitude of ≥0.060 mV in HB EGM was determined as the optimal value for identifying the acceptable threshold. This deep negative HB EGM was recorded with an HBP threshold of 1.4±1.3 V (in 34 attempts), significantly lower than that of positive HB EGM without deep negative deflection (2.8±1.3 V, in 31 trials; or >5 V, in 38 trials). The permanent HBP lead remained with deep negative (≥0.060 mV) or positive HB EGMs in 28 and 14 patients, respectively, and with positive or negative HB injury current in 19 and 23 patients, respectively. During follow-up, increased HBP threshold of >1 V was significantly more prevalent in the positive HB EGM group. The HBP thresholds of deep negative HB EGM and HB injury current, but not of the selective HBP group, were significantly lower than the other subgroups during follow-up. Conclusions Deep negative HB EGM at fixation was associated with an excellent short-term HBP threshold, similar to HB injury current. Analysis of unipolar HB EGM postfixation may enable prediction of permanent HBP threshold.


Assuntos
Potenciais de Ação , Bloqueio Atrioventricular/diagnóstico , Bloqueio Atrioventricular/terapia , Bradicardia/diagnóstico , Fascículo Atrioventricular/fisiopatologia , Estimulação Cardíaca Artificial , Técnicas Eletrofisiológicas Cardíacas , Frequência Cardíaca , Idoso , Idoso de 80 Anos ou mais , Bloqueio Atrioventricular/fisiopatologia , Bradicardia/fisiopatologia , Bradicardia/terapia , Estimulação Cardíaca Artificial/efeitos adversos , Feminino , Humanos , Masculino , Valor Preditivo dos Testes , Estudos Prospectivos , Sistema de Registros , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
16.
Circ Arrhythm Electrophysiol ; 12(6): e007293, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31122054

RESUMO

Background Catheter ablation of ventricular tachycardia (VT) in structural heart disease is challenging because of noninducibility or hemodynamic compromise. Ablation often depends on elimination of local abnormal ventricular activities (LAVAs) but which may be hidden in far-field signal. We investigated whether altering activation wavefront affects activation timing and LAVA characterization and allows a better understanding of isthmus anatomy. Methods Patients with ischemic cardiomyopathy underwent mapping using the ultra-high density Rhythmia system (Boston Scientific). Maps were generated for all stable VTs and with pacing from the atrium, right ventricular apex, and an left ventricular branch of the coronary sinus. Results Fifty-six paced maps and 23 VT circuits were mapped in 22 patients. In 79% of activation maps, there was ≥1 line of block in the paced conduction wavefront, with 93% having fixed block and 32% showing functional partial block. Bipolar scar was larger with atrial than right ventricular (31.7±18.5 versus 27.6±16.3 cm2, P=0.003) or left ventricular pacing (31.7±18.5 versus 27.0±19.2 cm2, P=0.009); LAVA areas were smaller with atrial than right ventricular (12.3±10.5 versus 18.4±11.0 cm2, P<0.001) or left ventricular pacing (12.3±10.5 versus 17.1±10.7 cm2, P<0.001). LAVA areas were larger with wavefront propagation perpendicular versus parallel to the line of block along isthmus boundaries (19.3±7.1 versus 13.6±7.4 cm2, P=0.01). All patients had successful VT isthmus ablation. In 11±8 months follow-up, 2 patients had a recurrence. Conclusions Wavefronts of conduction slowing/block may aid identification of critical isthmuses in unmappable VTs. Altering the activation wavefront leads to significant differences in conduction properties of myocardial tissue, along with scar and LAVA characterization. In patients where few LAVAs are identified during substrate mapping, using an alternate activation wavefront running perpendicular to the VT isthmus may increase sensitivity to detect arrhythmogenic substrate and critical sites for reentry.


Assuntos
Potenciais de Ação , Ablação por Cateter , Técnicas Eletrofisiológicas Cardíacas , Frequência Cardíaca , Ventrículos do Coração/cirurgia , Taquicardia Ventricular/cirurgia , Idoso , Estimulação Cardíaca Artificial , Ablação por Cateter/efeitos adversos , Feminino , Ventrículos do Coração/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Recidiva , Fatores de Risco , Volume Sistólico , Taquicardia Ventricular/diagnóstico , Taquicardia Ventricular/fisiopatologia , Fatores de Tempo , Resultado do Tratamento , Função Ventricular Esquerda
17.
Clin Cardiol ; 42(6): 644-652, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31038759

RESUMO

The cardiac autonomic nerve system (CANS) is a potentially potent modulator of the initiation and perpetuation of atrial fibrillation (AF). In this review, we focus on the relationship between the autonomic nervous system (ANS) and the pathophysiology of AF and the potential benefit and limitations of neuromodulation in the management of this arrhythmia from eight aspects. We conclude that Activation and Remodeling of CANS involved in the initiation and maintenance of AF. The network control mechanism, innervation regions, and sympathetic/parasympathetic balance play an important role in AF substrate. And the formation of Complex Fractional Atrial Electrograms also related to CANS activity. In addition, modulating CANS function by potential therapeutic applications include ganglionated plexus ablation, renal sympathetic denervation, and low-level vagal nerve stimulation, may enable AF to be controlled. Although the role of the ANS has long been recognized, a better understanding of the complex interrelationships of the various components of the CANS will lead to improvement of treatments for this common arrhythmia.


Assuntos
Fibrilação Atrial/fisiopatologia , Sistema Nervoso Autônomo/fisiopatologia , Ablação por Cateter/métodos , Átrios do Coração/fisiopatologia , Sistema de Condução Cardíaco/fisiopatologia , Sistema Nervoso Autônomo/cirurgia , Técnicas Eletrofisiológicas Cardíacas , Sistema de Condução Cardíaco/cirurgia , Humanos
18.
Card Electrophysiol Clin ; 11(2): 203-217, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31084847

RESUMO

Implantable loop recorders allow prolonged and continuous single-lead electrocardiogram recording, with the pivotal addition of remote monitoring. They have significantly shortened time to electrocardiographic diagnosis and appropriate therapy of many bradyarrhythmias/tachyarrhythmias and proved helpful in arrhythmia burden definition, offering invaluable information in the diagnostic workup for syncope and atrial fibrillation. Advanced cardiac signal recording is also possible by transesophageal catheters. They have been used to orient diagnosis during wide and narrow QRS complex tachycardias and also to perform minimally invasive pacing. Intracardiac electrophysiologic study remains, however, essential for diagnosis of several arrhythmias in the perspective of curative catheter ablation.


Assuntos
Técnicas Eletrofisiológicas Cardíacas , Processamento de Sinais Assistido por Computador , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/fisiopatologia , Humanos , Taquicardia/diagnóstico , Taquicardia/fisiopatologia
19.
Pesqui. vet. bras ; 39(5): 364-370, May 2019. graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1012748

RESUMO

Studies have demonstrated sympathetic cardiac denervation in the MPTP mouse model. MPTP toxicity causes sympathetic nerve damage and depletion of heart norepinephrine. Previous evaluations of impairments in heart innervation have been based on imaging, electrophysiological and biochemical methods. However, these studies lacked information that can be obtained from morphoquantitative analyses. Thus, this study aimed to apply a design-based stereological method for evaluating the morphoquantitative alterations of myocardium following treatment with the neurotoxin MPTP in the C57/BL mouse. Our results showed that MPTP reduced the number of cardiomyocytes in the left ventricle.(AU)


Estudos têm demonstrado a desnervação simpática cardíaca no modelo da administração do MPTP em camundongo. A toxicidade do MPTP causa lesão ao nervo simpático e depleção da norepinefrina. As avaliações dos danos na inervação do coração são baseadas em métodos de imagem, eletrofisiológico e bioquímico. Contudo, estes estudos carecem de informações provenientes de análises morfoquantitativas. Assim, objetivou-se aplicar métodos estereológicos para avaliar as alterações morfoquantitativas do miocárdio após o tratamento com a neurotoxina MPTP no camundongo C57/BL. Nossos resultados mostraram que o MPTP causa redução no número de cardiomiócitos no ventrículo esquerdo.(AU)


Assuntos
Animais , Ratos , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina/análise , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina/efeitos adversos , Camundongos/anatomia & histologia , Miocárdio/enzimologia , Técnicas Eletrofisiológicas Cardíacas/veterinária
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