RESUMO
BACKGROUND: Data on atrial fibrillation (AF) ablation and outcomes are limited in patients with congenital heart disease (CHD). We aimed to investigate the characteristics of patients with CHD presenting for AF ablation and their outcomes. METHODS: A multicenter, retrospective analysis was performed of patients with CHD undergoing AF ablation between 2004 and 2020 at 13 participating centers. The severity of CHD was classified using 2014 Pediatric and Congenital Electrophysiology Society/Heart Rhythm Society guidelines. Clinical data were collected. One-year complete procedural success was defined as freedom from atrial tachycardia or AF in the absence of antiarrhythmic drugs or including previously failed antiarrhythmic drugs (partial success). RESULTS: Of 240 patients, 127 (53.4%) had persistent AF, 62.5% were male, and mean age was 55.2±13.3 years. CHD complexity categories included 147 (61.3%) simple, 68 (28.3%) intermediate, and 25 (10.4%) severe. The most common CHD type was atrial septal defect (n=78). More complex CHD conditions included transposition of the great arteries (n=14), anomalous pulmonary veins (n=13), tetralogy of Fallot (n=8), cor triatriatum (n=7), single ventricle physiology (n=2), among others. The majority (71.3%) of patients had trialed at least one antiarrhythmic drug. Forty-six patients (22.1%) had reduced systemic ventricular ejection fraction <50%, and mean left atrial diameter was 44.1±8.2 mm. Pulmonary vein isolation was performed in 227 patients (94.6%); additional ablation included left atrial linear ablations (40%), complex fractionated atrial electrogram (19.2%), and cavotricuspid isthmus ablation (40.8%). One-year complete and partial success rates were 45.0% and 20.5%, respectively, with no significant difference in the rate of complete success between complexity groups. Overall, 38 patients (15.8%) required more than one ablation procedure. There were 3 (1.3%) major and 13 (5.4%) minor procedural complications. CONCLUSIONS: AF ablation in CHD was safe and resulted in AF control in a majority of patients, regardless of complexity. Future work should address the most appropriate ablation targets in this challenging population.
Assuntos
Fibrilação Atrial , Ablação por Cateter , Cardiopatias Congênitas , Veias Pulmonares , Transposição dos Grandes Vasos , Adulto , Idoso , Antiarrítmicos/uso terapêutico , Fibrilação Atrial/complicações , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/cirurgia , Ablação por Cateter/efeitos adversos , Ablação por Cateter/métodos , Criança , Feminino , Cardiopatias Congênitas/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Veias Pulmonares/cirurgia , Sistema de Registros , Estudos Retrospectivos , Resultado do TratamentoRESUMO
In this review, we emphasize the unique value of recording the activation sequence of the His bundle or right bundle branch (RB) for diagnoses of various supraventricular and fascicular tachycardias. A close analysis of the His to RB (H-RB) activation sequence can help differentiate various forms of supraventricular tachycardias, namely atrioventricular nodal reentry tachycardia from concealed nodofascicular tachycardia, a common clinical dilemma. Furthermore, bundle branch reentry tachycardia and fascicular tachycardias often are included in the differential diagnosis of supraventricular tachycardia with aberrancy, and the use of this technique can help the operator make the distinction between supraventricular tachycardias and these other forms of ventricular tachycardias using the His-Purkinje system. We show that this technique is enhanced by the use of multipolar catheters placed to span the proximal His to RB position to record the activation sequence between proximal His potential to the distal RB potential. This allows the operator to fully analyze the activation sequence in sinus rhythm as compared to that during tachycardia and may help target ablation of these arrhythmias. We argue that 3 patterns of H-RB activation are commonly identified-the anterograde H-RB pattern, the retrograde H-RB (right bundle to His bundle) pattern, and the chevron H-RB pattern (simultaneous proximal His and proximal RB activation)-and specific arrhythmias tend to be associated with specific H-RB activation sequences. We show that being able to record and categorize this H-RB relationship can be instrumental to the operator, along with standard pacing maneuvers, to make an arrhythmia diagnosis in complex tachycardia circuits. We highlight the importance of H-RB activation patterns in these complex tachycardias by means of case illustrations from our groups as well as from prior reports.
Assuntos
Fascículo Atrioventricular/fisiopatologia , Estimulação Cardíaca Artificial/métodos , Eletrocardiografia/métodos , Taquicardia Paroxística/diagnóstico , Taquicardia Ventricular/diagnóstico , Humanos , Taquicardia Paroxística/fisiopatologia , Taquicardia Paroxística/terapia , Taquicardia Ventricular/fisiopatologia , Taquicardia Ventricular/terapiaRESUMO
[Figure: see text].
Assuntos
Ablação por Cateter , Frequência Cardíaca , Fibrilação Ventricular/cirurgia , Complexos Ventriculares Prematuros/cirurgia , Potenciais de Ação , Adulto , Idoso , Antiarrítmicos/uso terapêutico , California , Estudos de Casos e Controles , Ablação por Cateter/efeitos adversos , Ablação por Cateter/mortalidade , Desfibriladores Implantáveis , Cardioversão Elétrica/instrumentação , Técnicas Eletrofisiológicas Cardíacas , Feminino , Frequência Cardíaca/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Tempo , Resultado do Tratamento , Fibrilação Ventricular/diagnóstico , Fibrilação Ventricular/mortalidade , Fibrilação Ventricular/fisiopatologia , Complexos Ventriculares Prematuros/diagnóstico , Complexos Ventriculares Prematuros/mortalidade , Complexos Ventriculares Prematuros/fisiopatologiaRESUMO
BACKGROUND Pulmonary vein (PV) stenosis is a rare condition characterized by progressive luminal size reduction of one or more pulmonary veins (PVs), which can increase postcapillary pressure resulting in shortness of breath, cough, hemoptysis, and pulmonary hypertension (PH). The diagnosis of PV stenosis requires a high degree of suspicion. PV stenosis is a rare but recognized complication of catheter-based radiofrequency ablation (RFA) for atrial fibrillation (AF). CASE REPORT We present a case of a 78-year-old man who underwent a surgical MAZE procedure followed by catheter-based RFA to treat AF. He subsequently developed shortness of breath, exercise limitation, and PH. The patient was ultimately diagnosed with PV stenosis, which was a sequela of the RFA and the cause of his PH. The patient was treated by stenting of his PV, with improvement in his exercise capacity and PH. Follow-up imaging showed improved pulmonary blood flow and reduced pulmonary pressures. CONCLUSIONS We conclude that PV stenosis should be high in the differential as the cause of dyspnea in patients with PH and a previous history of RFA for AF management. Early recognition and treatment can prevent complete occlusion of the affected PV and lead to an improvement in the patient's symptoms and quality of life.
Assuntos
Fibrilação Atrial , Ablação por Cateter , Hipertensão Pulmonar , Estenose de Veia Pulmonar , Idoso , Fibrilação Atrial/cirurgia , Ablação por Cateter/efeitos adversos , Catéteres , Humanos , Hipertensão Pulmonar/etiologia , Masculino , Qualidade de Vida , Estenose de Veia Pulmonar/diagnóstico por imagem , Estenose de Veia Pulmonar/etiologia , Resultado do TratamentoAssuntos
Técnicas de Ablação , Arritmias Cardíacas , Estimulação Cardíaca Artificial , Cardioversão Elétrica , Técnicas Eletrofisiológicas Cardíacas , Insuficiência Cardíaca , Potenciais de Ação , Animais , Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/epidemiologia , Arritmias Cardíacas/fisiopatologia , Arritmias Cardíacas/terapia , Desfibriladores Implantáveis , Cardioversão Elétrica/instrumentação , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/epidemiologia , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/terapia , Frequência Cardíaca , Humanos , Valor Preditivo dos Testes , Resultado do TratamentoRESUMO
BACKGROUND: Arrhythmias are a leading cause of death in adults with congenital heart disease (ACHD). While 24-48-hour monitors are often used to assess arrhythmia burden, extended continuous ambulatory rhythm monitors (ECAM) can record 2 weeks of data. The utility of this device and the arrhythmia burden identified beyond 48-hour monitoring have not been evaluated in the ACHD population. Additionally, the impact of ECAM has not been studied to determine management recommendations. OBJECTIVE: To address the preliminary question, we hypothesized that clinically significant arrhythmias would be detected on ECAM beyond 48 hours and this would lead to clinical management changes. METHODS: A single center retrospective cohort study of ACHD patients undergoing ECAM from June 2013 to May 2016 was performed. The number and type of arrhythmias detected within and beyond the first 48 hours of monitoring were compared using Kaplan-Meier curves and Cox proportional hazard models. RESULTS: Three hundred fourteen patients had monitors performed [median age 31 (IQR 25-41) years, 61% female). Significant arrhythmias were identified in 156 patients (50%), of which 46% were noted within 48 hours. A management change based on an arrhythmia was made in 49 patients (16%). CONCLUSIONS: ECAM detects more clinically significant arrhythmias than standard 48-hour monitoring in ACHD patients. Management changes, including medication changes, further testing or imaging, and procedures, were made based on results of ECAM. Recommendations and guidelines have been made based on arrhythmias on 48-hour monitoring; the predictive ability and clinical consequence of arrhythmias found on ECAM are not yet known.
Assuntos
Arritmias Cardíacas/etiologia , Eletrocardiografia Ambulatorial , Cardiopatias Congênitas/complicações , Frequência Cardíaca , Adulto , Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/fisiopatologia , Arritmias Cardíacas/terapia , Feminino , Cardiopatias Congênitas/diagnóstico , Cardiopatias Congênitas/fisiopatologia , Cardiopatias Congênitas/terapia , Humanos , Masculino , Valor Preditivo dos Testes , Prognóstico , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo , Adulto JovemAssuntos
Arritmias Cardíacas , Eletrofisiologia Cardíaca/tendências , Técnicas Eletrofisiológicas Cardíacas/tendências , Técnicas de Ablação/tendências , Potenciais de Ação , Animais , Antiarrítmicos/uso terapêutico , Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/genética , Arritmias Cardíacas/fisiopatologia , Arritmias Cardíacas/terapia , Estimulação Cardíaca Artificial/tendências , Difusão de Inovações , Cardioversão Elétrica/tendências , Predisposição Genética para Doença , Frequência Cardíaca , Humanos , Fenótipo , Fatores de Risco , Resultado do TratamentoRESUMO
BACKGROUND: The outcomes from pulmonary vein isolation (PVI) for atrial fibrillation (AF) are suboptimal, but the benefits of additional lesion sets remain unproven. Recent studies propose ablation of AF drivers improves outcomes over PVI, yet with conflicting reports in the literature. We undertook a systematic literature review and meta-analysis to determine outcomes from ablation of AF drivers in addition to PVI or as a stand-alone procedure. METHODS: Database search was done using the terms atrial fibrillation and ablation or catheter ablation and driver or rotor or focal impulse or FIRM (Focal Impulse and Rotor Modulation). We pooled data using random effects model and assessed heterogeneity with I2 statistic. RESULTS: Seventeen studies met inclusion criteria, in a cohort size of 3294 patients. Adding AF driver ablation to PVI reported freedom from AF of 72.5% (confidence interval [CI], 62.1%-81.8%; P<0.01) and from all arrhythmias of 57.8% (CI, 47.5%-67.7%; P<0.01). AF driver ablation when added to PVI or as stand-alone procedure compared with controls produced an odds ratio of 3.1 (CI, 1.3-7.7; P=0.02) for freedom from AF and an odds ratio of 1.8 (CI, 1.2-2.7; P<0.01) for freedom from all arrhythmias in 4 controlled studies. AF termination rate was 40.5% (CI, 30.6%-50.9%) and predicted favorable outcome from ablation(P<0.05). CONCLUSIONS: In controlled studies, the addition of AF driver ablation to PVI supports the possible benefit of a combined approach of AF driver ablation and PVI in improving single-procedure freedom from all arrhythmias. However, most studies are uncontrolled and are limited by substantial heterogeneity in outcomes. Large multicenter randomized trials are needed to precisely define the benefits of adding driver ablation to PVI.
Assuntos
Fibrilação Atrial/cirurgia , Ablação por Cateter , Veias Pulmonares/cirurgia , Potenciais de Ação , Adulto , Idoso , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/fisiopatologia , Ablação por Cateter/efeitos adversos , Feminino , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Intervalo Livre de Progressão , Veias Pulmonares/fisiopatologia , Recidiva , Fatores de Risco , Fatores de Tempo , Resultado do TratamentoRESUMO
BACKGROUND: The mechanisms by which persistent atrial fibrillation (AF) terminates via localized ablation are not well understood. To address the hypothesis that sites where localized ablation terminates persistent AF have characteristics identifiable with activation mapping during AF, we systematically examined activation patterns acquired only in cases of unequivocal termination by ablation. METHODS AND RESULTS: We recruited 57 patients with persistent AF undergoing ablation, in whom localized ablation terminated AF to sinus rhythm or organized tachycardia. For each site, we performed an offline analysis of unprocessed unipolar electrograms collected during AF from multipolar basket catheters using the maximum -dV/dt assignment to construct isochronal activation maps for multiple cycles. Additional computational modeling and phase analysis were used to study mechanisms of map variability. At all sites of AF termination, localized repetitive activation patterns were observed. Partial rotational circuits were observed in 26 of 57 (46%) cases, focal patterns in 19 of 57 (33%), and complete rotational activity in 12 of 57 (21%) cases. In computer simulations, incomplete segments of partial rotations coincided with areas of slow conduction characterized by complex, multicomponent electrograms, and variations in assigning activation times at such sites substantially altered mapped mechanisms. CONCLUSIONS: Local activation mapping at sites of termination of persistent AF showed repetitive patterns of rotational or focal activity. In computer simulations, complete rotational activation sequence was observed but was sensitive to assignment of activation timing particularly in segments of slow conduction. The observed phenomena of repetitive localized activation and the mechanism by which local ablation terminates putative AF drivers require further investigation.
Assuntos
Fibrilação Atrial/diagnóstico , Mapeamento Potencial de Superfície Corporal/métodos , Ablação por Cateter/métodos , Sistema de Condução Cardíaco/fisiopatologia , Frequência Cardíaca/fisiologia , Fibrilação Atrial/fisiopatologia , Fibrilação Atrial/cirurgia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Veias Pulmonares/cirurgia , Fatores de Tempo , Resultado do TratamentoRESUMO
There is a need for consensus recommendations for ionizing radiation dose optimization during multimodality medical imaging in children with congenital and acquired heart disease (CAHD). These children often have complex diseases and may be exposed to a relatively high cumulative burden of ionizing radiation from medical imaging procedures, including cardiac computed tomography, nuclear cardiology studies, and fluoroscopically guided diagnostic and interventional catheterization and electrophysiology procedures. Although these imaging procedures are all essential to the care of children with CAHD and have contributed to meaningfully improved outcomes in these patients, exposure to ionizing radiation is associated with potential risks, including an increased lifetime attributable risk of cancer. The goal of these recommendations is to encourage informed imaging to achieve appropriate study quality at the lowest achievable dose. Other strategies to improve care include a patient-centered approach to imaging, emphasizing education and informed decision making and programmatic approaches to ensure appropriate dose monitoring. Looking ahead, there is a need for standardization of dose metrics across imaging modalities, so as to encourage comparative effectiveness studies across the spectrum of CAHD in children.
Assuntos
Cardiopatias Congênitas/diagnóstico por imagem , Imagem Multimodal/normas , Doses de Radiação , Exposição à Radiação/normas , Radiografia Intervencionista/normas , Cintilografia/normas , Tomografia Computadorizada por Raios X/normas , Adolescente , Fatores Etários , Criança , Pré-Escolar , Consenso , Feminino , Fluoroscopia/normas , Humanos , Lactente , Recém-Nascido , Masculino , Imagem Multimodal/efeitos adversos , Imagem Multimodal/métodos , Segurança do Paciente/normas , Valor Preditivo dos Testes , Exposição à Radiação/efeitos adversos , Exposição à Radiação/prevenção & controle , Lesões por Radiação/prevenção & controle , Radiografia Intervencionista/efeitos adversos , Cintilografia/efeitos adversos , Medição de Risco , Fatores de Risco , Tomografia Computadorizada por Raios X/efeitos adversosRESUMO
AIMS: Focal Impulse and Rotor Modulation (FIRM) uses 64-electrode basket catheters to identify atrial fibrillation (AF)-sustaining sites for ablation, with promising results in many studies. Accordingly, new basket designs are being tested by several groups. We set out to determine the procedural safety of adding basket mapping and map-guided ablation to conventional pulmonary vein isolation (PVI). METHODS AND RESULTS: We collected 30 day procedural safety data in five US centres for consecutive patients undergoing FIRM plus PVI (FIRM-PVI) compared with contemporaneous controls undergoing PVI without FIRM. A total of 625 cases were included in this analysis: 325 FIRM-PVI and 300 PVI-controls. FIRM-PVI patients were more likely than PVI-controls to be male (83% vs. 66%, P < 0.001) and have long-standing persistent AF (26% vs. 13%, P < 0.001) reflecting patients referred for FIRM. Total ablation time was greater for FIRM-PVI (62 ± 22 min) vs. PVI-controls (52 ± 18 min, P = 0.03). The complication rate for FIRM-PVI procedures (4.3%) was similar to controls (4.0%, P = 1) for both major and minor complications; no deaths were reported. The rate of complications potentially attributable to the basket catheter was small and did not differ between basket types (Constellation 2.8% vs. FIRMap 1.8%, P = 0.7) or between cases in which basket catheters were and were not used (P = 0.5). Complication rates did not differ between centres (P = 0.6). CONCLUSIONS: Procedural complications from the use of the basket catheters for AF mapping are low, and thus procedural safety appears similar between FIRM-PVI and PVI-controls in a large multicentre cohort. Future studies are required to determine the optimal approach to maximize the efficacy of FIRM-guided ablation.
Assuntos
Fibrilação Atrial/mortalidade , Fibrilação Atrial/cirurgia , Mapeamento Potencial de Superfície Corporal/mortalidade , Ablação por Cateter/mortalidade , Ablação por Cateter/estatística & dados numéricos , Complicações Pós-Operatórias/mortalidade , Cirurgia Assistida por Computador/mortalidade , Fibrilação Atrial/diagnóstico por imagem , Mapeamento Potencial de Superfície Corporal/métodos , Mapeamento Potencial de Superfície Corporal/estatística & dados numéricos , Ablação por Cateter/métodos , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/prevenção & controle , Prevalência , Fatores de Risco , Cirurgia Assistida por Computador/métodos , Cirurgia Assistida por Computador/estatística & dados numéricos , Taxa de Sobrevida , Resultado do Tratamento , Estados Unidos/epidemiologiaRESUMO
BACKGROUND: Previous observations have reported that the number of pacing stimuli required to entrain a tachycardia varies on the basis of arrhythmia type and location, but a quantitative formulation of the number needed to entrain (NNE) that unifies these observations has not been characterized. OBJECTIVE: We sought to investigate the relationship between the number of pacing stimulations, the tachycardia cycle length (TCL), the overdrive pacing cycle length (PCL), and the postpacing interval (PPI) to accurately estimate the timing of tachycardia entrainment. METHODS: First, we detailed a mathematical derivation unifying electrophysiological parameters with empirical confirmation in 2 patients undergoing catheter ablation of typical atrial flutter. Second, we validated our formula in 44 patients who underwent various catheter ablation procedures. For accuracy, we corrected for rate-related changes in conduction velocity. RESULTS: We derived the equations NNE = |(PPI - TCL)/(TCL - PCL)| + 1 and Tachycardia advancement = (NNE - 1) × (TCL - PCL) - (PPI - TCL), which state that the NNE and the amount of tachycardia advancement on the first resetting stimulation are determined using regularly measured intracardiac parameters. In the retrospective cohort, the observed PPI - TCL highly correlated with the predicted PPI - TCL (mean difference 5.8 ms; r = 0.97; P < .001), calculated as PPI - TCL = (NNE - 1) × (TCL - PCL) - tachycardia advancement. CONCLUSION: The number of pacing stimulations required to entrain a reentrant tachycardia is predictable at any PCL after correcting for cycle length-dependent changes in conduction velocity. This relationship unifies established empirically derived diagnostic and mapping criteria for supraventricular tachycardia and ventricular tachycardia. This relationship may help elucidate when antitachycardia pacing episodes are ineffective or proarrhythmic and could potentially serve as a theoretical basis to customize antitachycardia pacing settings for improved safety and effectiveness.
Assuntos
Estimulação Cardíaca Artificial/métodos , Técnicas Eletrofisiológicas Cardíacas/métodos , Sistema de Condução Cardíaco/fisiopatologia , Frequência Cardíaca/fisiologia , Modelos Teóricos , Taquicardia Ventricular/diagnóstico , Adulto , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Taquicardia Ventricular/fisiopatologia , Taquicardia Ventricular/terapiaRESUMO
BACKGROUND: Because the His bundle is intrinsic to the circuit in orthodromic reciprocating tachycardia and remote from that of atrioventricular nodal reentrant tachycardia (AVNRT), pacing the His bundle during supraventricular tachycardia (SVT) may be useful to distinguish these arrhythmias. OBJECTIVE: The purpose of this study was to test the hypothesis that His overdrive pacing (HOP) would affect SVT immediately for orthodromic reciprocating tachycardia and in a delayed manner for AVNRT. METHODS: Once SVT was induced, HOP was performed by pacing the His bundle 10-30 ms faster than the SVT cycle length. The maneuver was determined to have entered the tachycardia circuit when a nonfused His-capture beat advanced or delayed the subsequent atrial electrogram by ≥10 ms or when the tachycardia was terminated. The number of beats required to enter each tachycardia with HOP was recorded. RESULTS: HOP was performed during 66 SVTs (26 atrioventricular reciprocating tachycardia [AVRT] and 40 AVNRT). Entry into the tachycardia within 1 beat had sensitivity of 92%, specificity of 92%, positive predictive value (PPV) of 89% and negative predictive value (NPV) of 95% to confirm the diagnosis of AVRT. A cutoff ≥3 beats to enter the circuit had sensitivity of 90%, specificity of 92%, PPV of 95% and NPV of 86% to confirm the diagnosis of AVNRT. HOP had sensitivity, specificity, PPV, and NPV of 100% for distinguishing septal AVRT from atypical AVNRT. CONCLUSION: HOP during SVT is a novel technique for distinguishing orthodromic reciprocating tachycardia from AVNRT. It can reliably distinguish between these arrhythmias with high sensitivity and specificity.
Assuntos
Fascículo Atrioventricular/fisiopatologia , Estimulação Cardíaca Artificial/métodos , Sistema de Condução Cardíaco/fisiopatologia , Taquicardia por Reentrada no Nó Atrioventricular/diagnóstico , Taquicardia Reciprocante/diagnóstico , Adolescente , Adulto , Diagnóstico Diferencial , Eletrocardiografia , Técnicas Eletrofisiológicas Cardíacas , Feminino , Seguimentos , Humanos , Masculino , Estudos Retrospectivos , Taquicardia por Reentrada no Nó Atrioventricular/fisiopatologia , Taquicardia por Reentrada no Nó Atrioventricular/terapia , Taquicardia Reciprocante/fisiopatologia , Taquicardia Reciprocante/terapia , Adulto JovemRESUMO
Ventricular arrhythmias, including ventricular fibrillation (VF) and sustained ventricular tachycardia (VT), are the principal causes of sudden cardiac death in patients with structural heart disease. While coronary artery disease is the predominant substrate associated with the development of VT, these arrhythmias are known to occur in a variety of disorders, including dilated cardiomyopathy, valvular and congenital heart disease, and cardiac ion channelopathies such as the long QT syndrome. In a minority of patients, VT occurs in the absence of structural heart disease. Despite the established mortality benefit of the implantable cardioverter defibrillator (ICD) in patients at risk of lethal arrhythmias, recurrent VT/VF events continue to be a source of morbidity and impaired quality of life in such patients. Antiarrhythmic therapy is indicated in select patients to treat symptomatic VT episodes, to reduce the incidence of ICD shocks, and potentially to improve quality of life and reduce hospitalizations related to cardiac arrhythmia. The primary adverse effects of antiarrhythmic medications are related to both cardiac and extracardiac toxicity, including the risk of proarrhythmia. Current drug therapy for ventricular arrhythmia has been limited by suboptimal efficacy in many patients, resulting in recurrent VT/VF events, and by drug toxicity or intolerance leading to discontinuation in a large percentage of patients. Amiodarone and sotalol are the principal agents used in the chronic treatment of VT. In addition, dronedarone and dofetilide, agents approved for the treatment of atrial fibrillation, and ranolazine, an antianginal agent, have been demonstrated to be protective against ventricular arrhythmia in small clinical studies. Finally, advances in basic electrophysiology have uncovered new molecular targets for the treatment of ventricular arrhythmia, and pharmacologic agents directed at these targets may emerge as promising VT treatments in the future. The roles of these current and emerging therapies for the treatment of VT in humans will be summarized in this review.
RESUMO
INTRODUCTION: Fascicular tachycardia (FT) is an uncommon cause of monomorphic sustained ventricular tachycardia (VT). We describe 6 cases of FT with multiform QRS morphologies. METHODS AND RESULTS: Six of 823 consecutive VT cases were retrospectively analyzed and found attributable to FT with multiform QRS patterns, with 3 cases exhibiting narrow QRS VT as well. All underwent electrophysiology study including fascicular potential mapping, entrainment pacing, and electroanatomic mapping. The first 3 cases describe similar multiform VT patterns with successful ablation in the upper mid septum. Initially, a right bundle branch block (RBBB) VT with superior axis was induced. Radiofrequency catheter ablation (RFCA) targeting the left posterior fascicle (LPF) resulted in a second VT with RBBB inferior axis. RFCA in the upper septum just apical to the LBB potential abolished VT in all cases. Cases 4 and 5 showed RBBB VT with alternating fascicular block compatible with upper septal dependent VT, resulting in bundle branch reentrant VT (BBRT) after ablation of LPF and left anterior fascicle (LAF). Finally, Cases 5 and 6 demonstrated spontaneous shift in QRS morphology during VT, implicating participation of a third fascicle. In Case 6, successful ablation was achieved over the proximal LAF, likely representing insertion of the auxiliary fascicle near the proximal LAF. CONCLUSIONS: Multiform FTs show a reentrant mechanism using multiple fascicular branches. We hypothesize that retrograde conduction over the septal fascicle produces alternate fascicular patterns as well as narrow VT forms. Ablation of the respective fascicle was successful in abolishing FT but does not preclude development of BBRT unless septal fascicle is targeted and ablated.
Assuntos
Fascículo Atrioventricular/cirurgia , Bloqueio de Ramo/diagnóstico , Bloqueio de Ramo/cirurgia , Ablação por Cateter , Técnicas Eletrofisiológicas Cardíacas , Taquicardia Ventricular/diagnóstico , Taquicardia Ventricular/cirurgia , Adolescente , Adulto , Idoso , Boston , Fascículo Atrioventricular/fisiopatologia , Bloqueio de Ramo/fisiopatologia , Estimulação Cardíaca Artificial , Ablação por Cateter/efeitos adversos , Criança , Humanos , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Retrospectivos , São Francisco , Taquicardia Ventricular/fisiopatologia , Resultado do Tratamento , Adulto JovemRESUMO
Ictal asystole is being recognized as a potential mechanism of sudden unexplained death in epilepsy (SUDEP). We report a case of a patient without known cardiac disease presenting with ictal asystole resulting in syncope, trauma, and need for pacemaker implantation. The management of ictal asystole is also briefly reviewed. This case is notable for the asystolic episode wholly captured on video-electroencephalogram/electrocardiogram, the serious risk of trauma and death posed to the patient, and its implications for the mechanism of ictal asystole. This report will alert physicians to the possibility of ictal arrhythmias as a cause of syncope and SUDEP in vulnerable patients.
Assuntos
Arritmias Cardíacas/etiologia , Arritmias Cardíacas/prevenção & controle , Estimulação Cardíaca Artificial/métodos , Epilepsia/complicações , Epilepsia/reabilitação , Adulto , Humanos , Masculino , Resultado do TratamentoRESUMO
This article reports an interesting case of a narrow complex tachycardia presenting the diagnostic dilemma of differentiating atrioventricular nodal reentrant tachycardia (AVNRT) from junctional tachycardia. It proposes delivering late-coupled premature atrial complexes during the tachycardia with short ventriculo-atrial interval as a diagnostic maneuver to differentiate AVNRT from junctional tachycardia in the electrophysiology laboratory. Treatments of these arrhythmias vary, and making the appropriate diagnosis of supraventricular tachycardia is essential to providing effective arrhythmia management.