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1.
J Card Surg ; 34(10): 1037-1043, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31374587

RESUMO

BACKGROUND: Endocardial catheter ablation has been shown to be effective in patients with paroxysmal atrial fibrillation (AF), and significantly less effective in patients with persistent AF (PAF). Lately, there is a trend toward a hybrid approach in the treatment of PAF that may be a more durable treatment for patients with PAF. In this manuscript we report our experience with the convergent ablation procedure in a PAF cohort. METHODS: This is a single center retrospective analysis of 31 patients with PAF who underwent the convergent procedure. All patients underwent surgical epicardial ablation of the posterior left atrial through a subxiphoid approach, followed by radiofrequency endocardial ablations on the same day. Patients were followed at 6 months intervals with static electrocardiograms or implanted devices. RESULTS: Sinus rhythm was achieved intraoperatively in all patients. Recurrence was defined according to Hearlt Rhythm Society definitions. At a median follow up of 17.7 months (IQR 11-24), the recurrence of atrial tachyarrhythmia (AF and atrial flutter) by Kaplan-Meier event free survival analysis occurred in 9 (29%) patients at 1-year follow up and 15 (48%) patients at 2-year follow up with or without the use of antiarrhythmic drugs. Recurrence of AF alone occurred in 4 (13%) patients at 1-year follow up and 9 (29%) patients at 2-year follow up patients. Complication rate in perioperative period was 12.9%. CONCLUSION: Our experience showed the hybrid procedure is a relatively safe and effective option for patients with PAF. Further studies are needed to better determine its long-term outcomes.


Assuntos
Fibrilação Atrial/cirurgia , Ablação por Cateter/métodos , Eletrocardiografia , Sistema de Condução Cardíaco/fisiopatologia , Idoso , Fibrilação Atrial/fisiopatologia , Intervalo Livre de Doença , Endocárdio/cirurgia , Feminino , Seguimentos , Sistema de Condução Cardíaco/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento
2.
Cardiol Young ; 29(6): 793-799, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31169097

RESUMO

INTRODUCTION: Catheter ablation of left posterior fascicular ventricular tachycardia in the pediatric population remains challenging, and most studies about this topic have been conducted on adult patients. This study aimed to assess the clinical presentation features and outcomes of catheter ablations performed using limited fluoroscopy with three-dimensional electroanatomic mapping system guidance in a pediatric left posterior fascicular ventricular tachycardia patient group. METHODS: A total of 20 consecutive patients undergoing left posterior fascicular ventricular tachycardia ablation at a single tertiary centre were enrolled. All children with left posterior fascicular ventricular tachycardia underwent electrophysiological studies using the EnSite NavX system guidance. Ablations were performed during the sinus rhythm based on the Purkinje potentials in all patients. RESULTS: The mean patient age was 12.7 years (range 2-16), and the mean patient weight was 51 kg (range 11-84). The mean procedure and median fluoroscopy times were 143.1 minutes and 3.4 minutes, respectively. No fluoroscopy was used in three patients. Acute success was achieved in 19 patients (95%). During a mean follow-up of 38.6 ± 19.35 months, left posterior fascicular ventricular tachycardia recurred in four patients (20%). Repeat ablations were performed successfully in those patients who developed recurrences. No complications were seen. CONCLUSIONS: Catheter ablation of left posterior fascicular ventricular tachycardia in children can be performed safely and effectively with low fluoroscopy exposure using a three-dimensional electroanatomic mapping system.


Assuntos
Mapeamento Potencial de Superfície Corporal/métodos , Ablação por Cateter/métodos , Fluoroscopia/métodos , Sistema de Condução Cardíaco/fisiopatologia , Cirurgia Assistida por Computador/métodos , Taquicardia Ventricular/cirurgia , Adolescente , Criança , Pré-Escolar , Feminino , Seguimentos , Sistema de Condução Cardíaco/cirurgia , Humanos , Imageamento Tridimensional , Masculino , Recidiva , Estudos Retrospectivos , Taquicardia Ventricular/diagnóstico , Taquicardia Ventricular/fisiopatologia , Resultado do Tratamento
3.
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
4.
Rev Port Cardiol ; 38(3): 187-192, 2019 03.
Artigo em Inglês, Português | MEDLINE | ID: mdl-30979530

RESUMO

INTRODUCTION AND AIMS: Remote magnetic navigation systems have demonstrated benefits in the ablation of difficult substrates. Their role in the ablation of atrioventricular nodal reentrant tachycardia (AVNRT), however, has only been studied in small patient series. The aim of this study was to compare the results of AVNRT ablation using magnetic navigation, in a center where every procedure is performed with this system, with manual ablation. METHODS: We selected 139 consecutive patients undergoing AVNRT ablation with magnetic navigation by a single operator between January 2009 and June 2016 and compared them to a group of 101 consecutive patients undergoing manual ablation in the same period by the same operator in another hospital. The methodology was the same in both groups. Success rates, complications, procedure time, radiofrequency time, total and operator fluoroscopy time, and recurrence rates were compared. RESULTS: There were no differences in success and complication rates. Procedure and total fluoroscopy times were not significantly different, but operator fluoroscopy time was significantly shorter with the magnetic navigation system (2.4±1.5 min vs. 7.2±4 min; p<0.001). The recurrence rate was higher in the manual group, although without statistical significance. CONCLUSIONS: The ablation of AVNRT with magnetic navigation is feasible using the same methodology as for manual ablation. Success and complication rates were similar. Operator fluoroscopy time was significantly less with the magnetic navigation system.


Assuntos
Ablação por Cateter/métodos , Fluoroscopia/métodos , Sistema de Condução Cardíaco/cirurgia , Magnetismo/métodos , Cirurgia Assistida por Computador/métodos , Taquicardia por Reentrada no Nó Atrioventricular/cirurgia , Feminino , Seguimentos , Sistema de Condução Cardíaco/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Estudos Retrospectivos , Taquicardia por Reentrada no Nó Atrioventricular/diagnóstico , Taquicardia por Reentrada no Nó Atrioventricular/fisiopatologia , Fatores de Tempo , Resultado do Tratamento
6.
PLoS Comput Biol ; 15(4): e1006765, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30951529

RESUMO

Although bipolar electrograms (Bi-egms) are commonly used for catheter mapping and ablation of cardiac arrhythmias, the accuracy and reproducibility of Bi-egms have not been evaluated. We aimed to clarify the influence of the catheter orientation (CO), catheter contact angle (CA), local conduction velocity (CV), scar size, and catheter type on the Bi-egm morphology using an in silico 3-dimensional realistic model of atrial fibrillation. We constructed a 3-dimensional, realistic, in silico left atrial model with activation wave propagation including bipolar catheter models. Bi-egms were obtained by computing the extracellular potentials from the distal and proximal electrodes. The amplitude and width were measured on virtual Bi-egms obtained under different conditions created by changing the CO according to the wave direction, catheter-atrial wall CA, local CV, size of the non-conductive area, and catheter type. Bipolar voltages were also compared between virtual and clinically acquired Bi-egms. Bi-egm amplitudes were lower for a perpendicular than parallel CO relative to the wave direction (p<0.001), lower for a 90° than 0° CA (p<0.001), and lower for a CV of 0.13m/s than 0.48m/s (p<0.001). Larger sized non-conductive areas were associated with a decreased bipolar amplitude (p<0.001) and increased bipolar width (p<0.001). Among three commercially available catheters (Orion, Pentaray, and Thermocool), those with more narrowly spaced and smaller electrodes produced higher voltages on the virtual Bi-egms (p<0.001). Multiple factors including the CO, CA, CV, and catheter design significantly influence the Bi-egm morphology. Universal voltage cut-off values may not be appropriate for bipolar voltage-guided substrate mapping.


Assuntos
Fibrilação Atrial/fisiopatologia , Fibrilação Atrial/cirurgia , Ablação por Cateter/instrumentação , Técnicas Eletrofisiológicas Cardíacas/instrumentação , Ablação por Cateter/estatística & dados numéricos , Biologia Computacional , Simulação por Computador , Eletrodos , Técnicas Eletrofisiológicas Cardíacas/estatística & dados numéricos , Fenômenos Eletrofisiológicos , Sistema de Condução Cardíaco/fisiopatologia , Sistema de Condução Cardíaco/cirurgia , Humanos , Modelos Cardiovasculares , Reprodutibilidade dos Testes , Interface Usuário-Computador
7.
BMJ Case Rep ; 12(3)2019 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-30936325

RESUMO

Runaway pacemaker is phenomenon in which pacemaker induces ventricular tachycardia as a result of some malfunction in the device. This entity is not very common in clinical practice. Normally, the pacemaker perceives the inherent cardiac impulse and hence averting the delivery of pacemaker stimulus in susceptible period of cardiac cycle. This is a case of a pacemaker-induced tachycardia (named as runaway pacemaker) in a patient with a history of Single Chamber Ventricular (VVI) pacemaker. A 75-year-old man was admitted with 3 days history of fluttering in the chest, shortness of breath, central chest and epigastric pain which radiated to the back. His medical history includes pacemaker implantation in 1996 with lead complication following which he was managed with VVI pacemaker, and the last procedure was generator change 4 years ago with no complication. Examination revealed ventricular tachycardia with ECG showing paced rhythm with ventricular pacing at the rate of 200-150/min. His pacemaker-induced ventricular tachycardia was immediately aborted after putting magnet on the device which restored his baseline rhythm with heart rate of 60/min. Pacemaker was explanted urgently with replacement of new pulse generator. The patient was discharged home with VVI pacemaker showing excellent parameters.


Assuntos
Arritmias Cardíacas/terapia , Sistema de Condução Cardíaco/cirurgia , Marca-Passo Artificial/efeitos adversos , Implantação de Prótese , Taquicardia Ventricular/etiologia , Idoso , Fontes de Energia Bioelétrica , Remoção de Dispositivo , Eletrocardiografia , Desenho de Equipamento , Falha de Equipamento , Sistema de Condução Cardíaco/fisiopatologia , Humanos , Masculino , Taquicardia Ventricular/fisiopatologia , Taquicardia Ventricular/cirurgia , Resultado do Tratamento
8.
J Interv Card Electrophysiol ; 55(3): 287-295, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30847732

RESUMO

BACKGROUND: First experiences using a 64-electrode mini-basket catheter (BC) paired with an automatic mapping system (Rhythmia™) for catheter ablation (CA) of ventricular ectopy (VE) and ventricular tachycardia (VT) have been reported. OBJECTIVES: We aimed to evaluate (1) differences in ventricular access for the BC and (2) benefit of this technology in the setting of standard clinical practice. METHODS: Patients (pts) undergoing CA for VE or VT using the Intellamap Orion™ paired with the Rhythmia™ automated-mapping system were included in this study. For LV access, transseptal and retrograde access were compared. RESULTS: All 32 pts (29 men, age 63 ± 15 years) underwent CA for VE (17 pts) or VT (15 pts). For mapping of VE originating from the left ventricle (LV) in 10 out of 13 pts, a transaortic access was feasible. The predominant access for CA of VT was transaortic (5/7). Feasibility and safety seem to be equal. The total procedure time was 179.1 ± 21.2 min for VE ablation and 212.0 ± 71.7 min for VT ablation (p = 0.177). For VE, an acquisition of 1602 ± 1672 map points and annotation of 140 ± 98 automated mapping points sufficed to abolish VE in all pts. During a 6-month follow-up (FU) after CA for VE, a VE burden reduction from 18.5 ± 2.1% to 2.8 ± 2.2% (p = 0.019) was achieved. In VT pts, one patient showed recurrence of sustained VT episodes during FU. CONCLUSION: Use of a high-resolution mapping system for VE/VT CA potentially facilitates revelation of VE origin and VT circuits in the setting of standard clinical practice. Feasibility and safety of a venous, transaortic, transseptal, or a combined approach seem to be equal.


Assuntos
Ablação por Cateter/métodos , Mapeamento Epicárdico/instrumentação , Sistema de Condução Cardíaco/fisiopatologia , Sistema de Condução Cardíaco/cirurgia , Ventrículos do Coração/fisiopatologia , Ventrículos do Coração/cirurgia , Taquicardia Ventricular/fisiopatologia , Taquicardia Ventricular/cirurgia , Eletrocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
9.
Int J Cardiol ; 285: 128-132, 2019 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-30857843

RESUMO

BACKGROUND: Cryoballoon (CB) versus radiofrequency (RF) ablation response on prothrombotic biomarkers obtained different results at short-term, while long-term is still unknown in atrial fibrillation (AF) treatment. We evaluated short and long-term changes in platelet and inflammatory biomarkers after CB and RF ablation. METHODS: Fifty-eight paroxysmal AF patients were randomized for pulmonary vein (PV) isolation using either CB (n = 29) or RF (n = 29) ablation. Biomarkers of platelet activation [P-selectin (CD62P), CD40 ligand (CD40L), platelet factor-4 (PF-4), mean platelet volume (MPV), platelet-leukocyte ratio (P-LCR), and platelet distribution width (PDW)]; and inflammatory [high sensitivity CRP (hs-CRP) and interleukin-6 (IL-6)] were measured at baseline, 18-24 h and 6-Months postablation. RESULTS: Twenty-four (86.2%) and twenty-six (89.7%) patients remained in sinus rhythm at 6-Months in CB and RF group respectively (p = 0.500). After 18-24 h postablation, CD62P, CD40L, PF-4, hs-CRP, and IL-6 levels were significantly activated in both groups (p < 0.001). However, CD62P was significantly lower in CB than RF (p = 0.017). At 6-Month postablation in CB group, all platelet biomarkers CD62P (p = 0.021), CD40L (p < 0.001), PF-4 (p < 0.001), MPV (p = 0.010), PDW (p = 0.004), and P-LCR (p = 0.033) were significantly decreased compared to baseline levels. However in RF group, CD40L and PF-4 (p < 0.001) significant decreased, CD62P (p = 0.022) increased, and no change in MPV and P-LCR (p > 0.05) compared to baseline levels. hs-CRP and IL-6 levels were comparable between baseline and 6-Months in both groups (p > 0.05). CONCLUSIONS: CB ablation might influence the risk of thromboembolism due to less platelet activation after PV isolation and decreased platelet activation at long-term in maintained sinus rhythm patients compared to RF.


Assuntos
Fibrilação Atrial/sangue , Plaquetas/metabolismo , Ablação por Cateter/métodos , Criocirurgia/métodos , Sistema de Condução Cardíaco/cirurgia , Inflamação/sangue , Ativação Plaquetária/fisiologia , Fibrilação Atrial/fisiopatologia , Fibrilação Atrial/cirurgia , Biomarcadores/sangue , Feminino , Seguimentos , Sistema de Condução Cardíaco/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Estudos Retrospectivos , Fatores de Tempo
10.
Cardiol Clin ; 37(2): 207-219, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30926022

RESUMO

Catheter ablation for atrial fibrillation has improved in part due to advances in technology and techniques. Improved power delivery through contact force and irrigation and new balloon-based catheter systems for pulmonary vein isolation have resulted in greater success in paroxysmal atrial fibrillation. New tools are under development to facilitate understanding targets for ablation in persistent atrial fibrillation and create permanent ablation lesions safely and quickly.


Assuntos
Fibrilação Atrial/cirurgia , Mapeamento Potencial de Superfície Corporal/métodos , Ablação por Cateter/instrumentação , Sistema de Condução Cardíaco/fisiopatologia , Fibrilação Atrial/fisiopatologia , Desenho de Equipamento , Sistema de Condução Cardíaco/cirurgia , Humanos , Período Intraoperatório , Veias Pulmonares/cirurgia , Irrigação Terapêutica/métodos , Resultado do Tratamento
13.
Pacing Clin Electrophysiol ; 42(3): 321-326, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30653680

RESUMO

BACKGROUND: The deterioration of left atrial and ventricular functions was demonstrated in patients with frequent ventricular extrasystole (fVES). The exact pathophysiology of left atrial dysfunction in patients with fVES is unclear. Retrograde ventriculoatrial conduction (VAC) often accompanies fVES, which may contribute to atrial dysfunction. We investigated whether atrial electromechanical delay and VAC are related to these atrial functions in patients with frequent right ventricular outflow tract (RVOT) VES and preserved ejection fraction (pEF). METHODS: This study included 21 patients with pEF (eight males, 48 ± 11 years), who had experienced more than 10 000 RVOT-VES during 24-h Holter monitoring and had undergone electrophysiological study/ablation. The study also included 20 healthy age- and sex-matched control subjects. Transthoracic echocardiography was performed on all of the subjects. Atrial conduction time was obtained by using tissue Doppler imaging. Strain analysis was performed with two-dimensional speckle tracking echocardiography. RESULTS: The peak atrial longitudinal strain was significantly impaired in patients with fVES (P = 0.01). In addition, although the interatrial and left atrial conduction delay times were significantly different between each group (P < 0.001, P < 0.001), the right atrial conduction delay times were similar. When patients with fVES were divided into groups depending on the existence of retrograde VAC, atrial deformation parameters and conduction delay time did not significantly differ between either group. CONCLUSION: Frequent RVOT-VES causes left atrial dysfunction. This information is obtained through strain analyses and recordings of left atrial conduction times in patients with pEF. Regardless, retrograde VAC is not related to atrial dysfunction.


Assuntos
Complexos Cardíacos Prematuros/fisiopatologia , Átrios do Coração/fisiopatologia , Sistema de Condução Cardíaco/fisiopatologia , Volume Sistólico , Obstrução do Fluxo Ventricular Externo/fisiopatologia , Complexos Cardíacos Prematuros/cirurgia , Estudos de Casos e Controles , Ablação por Cateter , Ecocardiografia Doppler , Eletrocardiografia Ambulatorial , Feminino , Átrios do Coração/cirurgia , Sistema de Condução Cardíaco/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Obstrução do Fluxo Ventricular Externo/cirurgia
14.
Heart Vessels ; 34(4): 616-624, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30291411

RESUMO

There are some cases that are difficult to cure with only circumferential pulmonary vein isolation (CPVI) of persistent atrial fibrillation (PerAF). Recently, prolonged interatrial conduction times (IACTs), which seem to be associated with progressive remodeled atria, have been reported as a predictor of new-onset AF. This study aimed to investigate the prognostic value of a prolonged IACT for predicting AF recurrences after CPVI of PerAF. One hundred thirteen patients who underwent CPVI without an empirical substrate modification of PerAF were retrospectively analyzed. The IACT was defined as the interval from the earliest P-wave onset on the ECG to the latest activation in the coronary sinus and was measured after achieving the CPVI and conversion to sinus rhythm. During a mean 22.7-month follow-up after the initial procedure, 56 patients (50%) had AF recurrences. Patients with AF recurrence had a longer IACT than those without AF recurrence (p < 0.001). The best discriminative cut-off value for the IACT was 123 ms (sensitivity 53%, specificity 85%). In a Cox multivariate analysis, a prolonged IACT of ≥ 123 ms was the only independent predictor (hazard ratio: 2.38; 95% confidence interval: 1.36-4.16, p = 0.002) of being associated with the incidence of an AF recurrence. Even after multiple CPVI procedures, patients with an IACT ≥ 123 ms had a higher AF recurrence rate than those with an IACT < 123 ms (p = 0.002). In conclusion, a prolonged IACT of ≥ 123 ms may be a useful marker for predicting AF recurrences after both initial and multiple CPVI procedures for PerAF.


Assuntos
Fibrilação Atrial/cirurgia , Ablação por Cateter/métodos , Sistema de Condução Cardíaco/cirurgia , Frequência Cardíaca/fisiologia , Veias Pulmonares/cirurgia , Fibrilação Atrial/fisiopatologia , Mapeamento Potencial de Superfície Corporal , Feminino , Seguimentos , Sistema de Condução Cardíaco/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento
15.
Int J Cardiol ; 278: 114-119, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30391065

RESUMO

BACKGROUND: Low voltage zones (LVZs) are associated with conduction velocity (CV) slowing. Rate-dependent CV slowing may play a role in reentry mechanisms. METHODS: Patients undergoing catheter ablation for AT were enrolled. Aim was to assess the relationship between rate-dependent CV slowing and sites of localized reentrant atrial tachycardias (AT). On a bipolar voltage map regions were defined as non-LVZs [≥0.5 mV], LVZs [0.2-0.5 mV] and very-LVZs [<0.2 mV]. Unipolar electrograms were recorded with a 64-pole basket catheter during uninterrupted atrial pacing at four pacing intervals (PIs) during sinus rhythm. CVs were measured between pole pairs along the wavefront path. Sites of rate-dependent CV slowing were defined as exhibiting a reduction in CV between PI = 600 ms and 250 ms of ≥20% more than the mean CV reduction seen between these PIs for that voltage zone. Rate-dependent CV slowing sites were correlated to sites of localized reentrant ATs as confirmed with conventional mapping, entrainment and response to ablation. RESULTS: Eighteen patients were included (63 ±â€¯10 years). Mean CV at 600 ms was 1.53 ±â€¯0.19 m/s in non-LVZs, 1.14 ±â€¯0.15 m/s in LVZs, and 0.73 ±â€¯0.13 m/s in very-LVZs respectively (p < 0.001). Rate-dependent CV slowing sites were predominantly in LVZs [0.2-0.5 mV] (74.4 ±â€¯10.3%; p < 0.001). Localized reentrant ATs were mapped to these sites in 81.8% of cases (sensitivity 81.8%, 95% CI 48.2-97.9% and specificity 83.9%, 95% CI 81.8-86.0%). Macro-reentrant or focal ATs were not mapped to sites of rate-dependent CV slowing. CONCLUSIONS: Rate-dependent CV slowing sites are predominantly confined to LVZs [0.2-0.5 mV] and the resultant CV heterogeneity may promote reentry mechanisms. These may represent a novel adjunctive target for AT ablation.


Assuntos
Fibrilação Atrial/fisiopatologia , Ablação por Cateter/métodos , Átrios do Coração/fisiopatologia , Sistema de Condução Cardíaco/fisiopatologia , Frequência Cardíaca/fisiologia , Idoso , Fibrilação Atrial/diagnóstico por imagem , Fibrilação Atrial/cirurgia , Ablação por Cateter/tendências , Feminino , Átrios do Coração/diagnóstico por imagem , Sistema de Condução Cardíaco/diagnóstico por imagem , Sistema de Condução Cardíaco/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos
16.
Comput Biol Med ; 104: 339-351, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30442428

RESUMO

We review some of the latest approaches to analysing cardiac electrophysiology data using machine learning and predictive modelling. Cardiac arrhythmias, particularly atrial fibrillation, are a major global healthcare challenge. Treatment is often through catheter ablation, which involves the targeted localised destruction of regions of the myocardium responsible for initiating or perpetuating the arrhythmia. Ablation targets are either anatomically defined, or identified based on their functional properties as determined through the analysis of contact intracardiac electrograms acquired with increasing spatial density by modern electroanatomic mapping systems. While numerous quantitative approaches have been investigated over the past decades for identifying these critical curative sites, few have provided a reliable and reproducible advance in success rates. Machine learning techniques, including recent deep-learning approaches, offer a potential route to gaining new insight from this wealth of highly complex spatio-temporal information that existing methods struggle to analyse. Coupled with predictive modelling, these techniques offer exciting opportunities to advance the field and produce more accurate diagnoses and robust personalised treatment. We outline some of these methods and illustrate their use in making predictions from the contact electrogram and augmenting predictive modelling tools, both by more rapidly predicting future states of the system and by inferring the parameters of these models from experimental observations.


Assuntos
Fibrilação Atrial/fisiopatologia , Eletrocardiografia , Técnicas Eletrofisiológicas Cardíacas , Sistema de Condução Cardíaco/fisiopatologia , Aprendizado de Máquina , Modelos Cardiovasculares , Fibrilação Atrial/cirurgia , Ablação por Cateter , Sistema de Condução Cardíaco/cirurgia , Humanos
17.
Heart Lung Circ ; 28(1): 84-101, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30385114

RESUMO

Non-ischaemic cardiomyopathy (NICM) encompasses a heterogeneous group of disorders that includes genetic, idiopathic, post viral and inflammatory cardiomyopathies. NICM is associated with an increased risk of ventricular arrhythmias (VAs), namely in the form of ventricular tachycardia (VT). Although implanted cardiac defibrillators (ICD) may prevent sudden death from VA, NICM patients may suffer from recurrent symptoms and ICD therapies, and anti-arrhythmic drug side effects. Catheter ablation is highly efficacious in NICM, however poses unique challenges when compared to post myocardial infarction substrates. NICM substrates are fundamentally different in scar location, extent, and transmurality which results in variable electrophysiologic properties and less apparent ablation targets during sinus rhythm, compared to ischaemic cardiomyopathy. NICM substrates can be intramural and/or epicardial, posing challenges to accessibility, which likely accounts for the observed higher rates of arrhythmia recurrence following ablation. Substrate location is influenced by the underlying aetiology (inflammatory, genetic), and can be gleaned from a combination of unique 12-lead electrocardiogram VT patterns, distribution of late gadolinium enhancement on cardiac magnetic resonance imaging, and electroanatomic voltage mapping. With the high proportion of intramural substrate in NICM, novel techniques have become increasingly common in recent years, including sequential, simultaneous or bipolar ablation on opposite myocardial surfaces to achieve greater lesion depth; use of half normal saline for irrigation; use of a novel retractable needle within an endocardial catheter; and transcoronary/venous ethanol ablation to target more inaccessible regions. Epicardial approaches have also been improved in recent years, with advents such as the needle-in-needle technique to reduce the risk of pericardial bleeding and phrenic nerve displacement, and hybrid surgical approaches to facilitate epicardial access in the presence of adhesions. Non-invasive cardiac radiation holds promise for the future. This state-of-the-art review will summarise the incidence, mechanism, multimodal assessment and catheter ablation-based management of VA in NICM.


Assuntos
Cardiomiopatias/complicações , Ablação por Cateter/métodos , Sistema de Condução Cardíaco/cirurgia , Taquicardia Ventricular/cirurgia , Endocárdio , Humanos , Pericárdio , Taquicardia Ventricular/etiologia
18.
Heart Vessels ; 34(3): 496-502, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30302548

RESUMO

Observation of the time-to-pulmonary vein isolation (TTI) by a spiral mapping catheter has emerged as a valuable procedural parameter in cryoballoon pulmonary vein isolation (PVI). The 1st generation spiral mapping catheter (Achieve, SMC1) has been available as an 8-polar catheter with a distal loop diameter of 15 or 20 mm. The novel spiral mapping catheter (Achieve Advance, SMC2) was designed as a true guidewire and is available, in addition to the sizes of the SMC1, as a 10-polar mapping catheter with a distal loop diameter of 25 mm. Whether these novel features of SMC2 influence procedural characteristics of Cryo-PVI in comparison to SMC1 has not been reported. In this prospective cohort study 158 patients (age 65.1 ± 12.4 years, female 39%, paroxysmal AF 60%) undergoing PVI with the 2nd generation cryoballoon were included. SMC1 was used in 57 patients (36%), whereas 101 patients (64%) underwent Cryo-PVI with the SMC2. All PVs (623/623, 100%) were isolated successfully. Mean procedure duration was 72.0 ± 18.9 min in the SMC1 group and 74.4 ± 19.1 min in the SMC2 group (p = 0.432). Mean fluoroscopy time was also not different between both study groups (SMC1 15.7 ± 6.6 min, SMC2 15.7 ± 7.3 min, p = 0.593). TTI was observed in 68.6% of pulmonary veins in the SMC1 group, whereas TTI observation rate was 82.6% in the SMC2 group (p < 0.001). Number of freezes (5.5 ± 1.5 vs. 6.5 ± 1.9; p = 0.001) and total freeze duration (14.1 ± 4.5 vs. 17.6 ± 5.6; p < 0.001) were increased in the SMC2 group. SMC2 significantly increases TTI observation rate during Cryo-PVI. Procedure duration and fluoroscopy time are similar and number of freezes and total freeze duration are increased compared to PVI with SMC1 due to decreased stability and maneuverability of SMC2.


Assuntos
Fibrilação Atrial/diagnóstico , Cateteres , Criocirurgia/instrumentação , Sistema de Condução Cardíaco/cirurgia , Veias Pulmonares/cirurgia , Idoso , Fibrilação Atrial/fisiopatologia , Fibrilação Atrial/cirurgia , Desenho de Equipamento , Feminino , Fluoroscopia , Seguimentos , Sistema de Condução Cardíaco/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Tempo para o Tratamento
20.
Heart Vessels ; 34(2): 352-359, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30140958

RESUMO

Inflammation, oxidative stress, myocardial injury biomarkers and clinical parameters (longer AF duration, left atrial enlargement, the metabolic syndrome) are factors commonly related to AF recurrence. This study aims to assess the predictive value of laboratory and clinical parameters responsible for early recurrence of atrial fibrillation (ERAF) following cryoballoon ablation (CBA) using statistical assessment and machine learning algorithms. This study group comprised 118 consecutive patients (mean age, 62.5 ± 7.8 years; women 36%) with paroxysmal (54.1%) and persistent (45.9%) AF who underwent their first pulmonary vein isolation (PVI) performed by CBA (Arctic Front Advance 2nd generation 28 mm). The biomarker concentrations were measured at baseline and after CBA in a 24-h follow-up. ERAF was defined as at least a 30-s episode of arrhythmia registered by a 24 h-Holter monitor within the 3 months following the procedure. 56 clinical, laboratory and procedural variables were collected from each patient. We used two classification algorithms: support vector machines, gradient boosted tree. The synthetic minority over-sampling technique (SMOTE) was used to provide a balanced training data set. Within a period of 3 months 21 patients (17.8%) experienced ERAF. The statistical analysis indicated that the lowered levels of post-ablation TnT (p = 0.043) and CK-MB (p = 0.010) with the TnT elevation (p = 0.044) were the predictors of ERAF following CBA. In addition, diabetes and statin treatment were significantly associated with ERAF after CBA (p < 0.05). The machine learning algorithms confirmed the results obtained in the univariate analysis.


Assuntos
Algoritmos , Fibrilação Atrial/cirurgia , Criocirurgia/métodos , Sistema de Condução Cardíaco/cirurgia , Aprendizado de Máquina , Veias Pulmonares/cirurgia , Fibrilação Atrial/fisiopatologia , Eletrocardiografia Ambulatorial , Feminino , Seguimentos , Sistema de Condução Cardíaco/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Recidiva , Estudos Retrospectivos , Fatores de Tempo
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