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1.
JACC Clin Electrophysiol ; 9(10): 2172-2196, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37498247

RESUMO

Of the monomorphic ventricular tachycardias, there are 4 specific tachycardias related to the Purkinje system: 1) idiopathic verapamil-sensitive fascicular ventricular tachycardia (FVT); 2) non-re-entrant FVT; 3) bundle branch re-entry and interfascicular re-entry; and 4) Purkinje-mediated VT in structural heart disease. Verapamil-sensitive FVT is classified into 4 types according to the location of the circuit: 1) left posterior type; 2) left anterior type; 3) left upper septal type;and 4) reverse type. And, in the left anterior and posterior types, there are septal and papillary muscle subtypes. Although macro-re-entry has been reported to be the mechanism underlying verapamil-sensitive FVT, recording the entire circuit is challenging. One possible reason is that the Purkinje-muscle junction may penetrate the myocardial layer as a part of the circuit. The Purkinje network may thus play an important role in the initiation and maintenance of ventricular fibrillation. Further, it has been reported that the development and the abnormalities of the Purkinje system are associated with the arrhythmogenesis of ventricular fibrillation. Furthermore, it has been reported that catheter ablation of trigger ventricular premature complexes, and/or "de-networking" of the Purkinje system, can be used as electrical bailout therapy. There is a hypothesis that the intramural Purkinje system is involved in the generation of J waves. Nevertheless, as there are still unresolved issues that must be debated and accurately analyzed, this review aims to discuss the solved and unsolved questions related to Purkinje-related arrhythmias.


Assuntos
Taquicardia Ventricular , Complexos Ventriculares Prematuros , Humanos , Fibrilação Ventricular/etiologia , Fibrilação Ventricular/terapia , Ramos Subendocárdicos , Taquicardia Ventricular/cirurgia , Verapamil
2.
Korean Circ J ; 50(4): 289-301, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31960637

RESUMO

Brugada syndrome (BrS) is an arrhythmogenic disease associated with an increased risk of ventricular fibrillation (VF) and sudden cardiac death (SCD). To date, the standard therapy for the prevention of SCD in BrS is the use of an implantable cardioverter-defibrillator (ICD) especially in patients who have experienced a prior cardiac arrest or syncopal events secondary to VF. However, ICDs do not prevent the occurrence of VF but react to defibrillate the VF episode, thereby preventing SCD. Often patients with recurrent VF have to be maintained on antiarrhythmic drugs that are effective but have remarkable adverse effects. An alternative therapy for BrS with recurrent VF is catheter ablation which emerged as an effective therapy in eliminating VF-triggering premature ventricular complexes in limited case series; however, there has been a remarkable progress in effectiveness of catheter ablation since epicardial substrate ablation was first applied in 2011 and such approach is now widely applicable.

3.
Card Electrophysiol Clin ; 11(4): 609-623, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31706469

RESUMO

Fascicular ventricular tachycardia (FVT) usually involves the left fascicular system; namely the left posterior fascicle, anterior fascicle, and rarely the upper septal fascicle. It may also involve the right Purkinje arborization. This tachycardia can be seen in normal heart or in the setting of structural heart diseases. Monomorphic FVT can be reentrant or nonreentrant and verapamil-sensitive left FVT is the second most common type of idiopathic ventricular tachycardia (VT) after right ventricular outflow tract VT. This article focuses on the practical approach for both reentrant and nonreentrant FVT, explaining the mechanism, electrocardiographic features, and electrophysiologic features of FVT.


Assuntos
Ablação por Cateter , Técnicas Eletrofisiológicas Cardíacas , Taquicardia Ventricular , Humanos , Taquicardia Ventricular/diagnóstico , Taquicardia Ventricular/fisiopatologia , Taquicardia Ventricular/cirurgia
4.
Circ Arrhythm Electrophysiol ; 11(8): e005631, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30354308

RESUMO

Background Both endocardial trigger elimination and epicardial substrate modification are effective in treating ventricular fibrillation (VF) in Brugada syndrome. However, the primary approach and the characteristics of patients who respond to endocardial ablation remain unknown. Methods Among 123 symptomatic Brugada syndrome patients (VF, 63%; syncope, 37%), ablation was performed in 21 VF/electrical storm patients, the majority of whom were resistant to antiarrhythmic drugs. Results Careful endocardial mapping revealed that 81% of the patients had no specific findings, whereas 19% of the patients, who experienced the most frequent VF episodes with notching of the QRS in lead V1, had delayed low-voltage fractionated endocardial electrograms. Ablation of VF triggers followed by endocardial substrate modification was performed in the right ventricular outflow tract in 85% of the cases and in the right ventricle in 15%. VF triggers could not be completely eliminated in 1 patient and VF became noninducible in 14 (88%) patients among 16 patients who underwent VF induction with normalization of Brugada-type ECG in 3. During follow-up (56.14±36.95 months), VF recurrence was observed in 7 patients. Importantly, all patients who had nothing of QRS in lead V1 did not respond to endocardial ablation despite presence of VF-triggering ectopic beats during ablation. Conclusions With careful documentation of VF-triggering ectopic beats and detailed endocardial mapping, endocardial VF trigger elimination followed by endocardial substrate modification has an excellent long-term outcome, whereas presence of QRS notching in lead V1 was associated with high VF recurrence suggesting epicardial substrate ablation as effective initial approach.


Assuntos
Síndrome de Brugada/complicações , Ablação por Cateter/métodos , Endocárdio/cirurgia , Frequência Cardíaca , Fibrilação Ventricular/cirurgia , Potenciais de Ação , Adulto , Antiarrítmicos/uso terapêutico , Síndrome de Brugada/diagnóstico , Síndrome de Brugada/fisiopatologia , Ablação por Cateter/efeitos adversos , Resistência a Medicamentos , Eletrocardiografia , Técnicas Eletrofisiológicas Cardíacas , Endocárdio/fisiopatologia , Feminino , Frequência Cardíaca/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Fibrilação Ventricular/diagnóstico , Fibrilação Ventricular/etiologia , Fibrilação Ventricular/fisiopatologia
5.
JACC Clin Electrophysiol ; 4(3): 339-350, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-30089559

RESUMO

OBJECTIVES: This study evaluated the characteristics and results of radiofrequency catheter ablation (RFCA) of ventricular tachycardia (VT) in patients with hypertrophic cardiomyopathy (HCM) and left ventricular apical aneurysm (AA). BACKGROUND: Monomorphic VT in patients with HCM and left ventricular AA has been reported. However, outcome data of RFCA are insufficient. METHODS: Fifteen patients with HCM and AA who underwent RFCA for VT at 5 different institutions were included in this study. The data were evaluated retrospectively. RESULTS: Endocardial voltage mapping showed a low-voltage area (LVA), and late potential in the AA was recorded in 12 patients (80%). Although epicardial or intramural origin of VT was suspected in 7 patients, endocardial RFCA successfully suppressed the VT at the LVA border (n = 10) or within the LVA (n = 2). In 2 of 3 patients without LVA at the endocardial site, linear RFCA at the anterior wall of the aneurysmal neck side was successful. In the remaining patient, endocardial RFCA of AA was not effective, and epicardial RFCA site was needed. In all patients, clinical VT became noninducible after RFCA. VT recurrence was observed in 2 patients (13.3%) during the 12-month follow-up period. One patient underwent a second endocardial RFCA, and no VT recurrence was noted. In the other patient, VT recurred 3 months after RFCA and was successfully terminated by antitachycardia pacing of the implantable cardioverter-defibrillator. CONCLUSIONS: In patients with HCM and AA, endocardial RFCA of AA effectively suppressed monomorphic VT which was related to AA and resulted in satisfactory outcomes.


Assuntos
Cardiomiopatia Hipertrófica , Ablação por Cateter , Aneurisma Cardíaco , Taquicardia Ventricular , Idoso , Idoso de 80 Anos ou mais , Cardiomiopatia Hipertrófica/complicações , Cardiomiopatia Hipertrófica/epidemiologia , Ablação por Cateter/efeitos adversos , Ablação por Cateter/métodos , Ablação por Cateter/estatística & dados numéricos , Eletrocardiografia , Técnicas Eletrofisiológicas Cardíacas , Feminino , Aneurisma Cardíaco/complicações , Aneurisma Cardíaco/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Taquicardia Ventricular/complicações , Taquicardia Ventricular/epidemiologia , Taquicardia Ventricular/fisiopatologia , Taquicardia Ventricular/cirurgia , Resultado do Tratamento
7.
Artigo em Inglês | MEDLINE | ID: mdl-28292752

RESUMO

BACKGROUND: Verapamil-sensitive fascicular ventricular tachycardia (FVT) has been demonstrated to be a reentrant mechanism using the Purkinje network as a part of its reentrant circuit. Although the papillary muscles (PMs) are implicated in arrhythmogenic structure, reentrant FVT originating from the PMs has not been well defined. METHODS AND RESULTS: We studied 13 patients in whom FVT was successfully eliminated by ablation at the posterior PMs (n=8; PPM-FVT) and anterior PMs (n=5; APM-FVT). Although intravenous administration of verapamil (5 mg) terminated ventricular tachycardia (VT) in 6 patients, VT was only slowed in the remaining 7 patients. PPM-FVT exhibited right bundle branch block and superior right axis (extreme right axis) or horizontal axis deviation. APM-FVT exhibited right bundle branch block configuration and right axis deviation with deep S wave in leads I, V5, and V6. VT was reproducibly induced by programmed atrial or ventricular stimulation. His-ventricular interval during VT was shorter than that during sinus rhythm. Ablation at the left posterior or anterior fascicular regions often changed the QRS morphology but did not completely eliminate it. Mid-diastolic Purkinje potentials were recorded during VT around the PMs, where ablation successfully eliminated the tachycardia. All patients have been free from recurrent VT after ablation. CONCLUSIONS: Reentrant circuit of verapamil-sensitive FVT can involve the Purkinje network lying around the PMs. PM-FVT is a distinct entity that is characterized by distinctive electrocardiographic characteristics and less sensitivity to verapamil administration compared with common type FVT. Ablation targeting the mid-diastolic Purkinje potentials around the PMs during tachycardia can be effective in suppressing this arrhythmia.


Assuntos
Ablação por Cateter/métodos , Eletrocardiografia , Ramos Subendocárdicos/fisiopatologia , Taquicardia Ventricular/cirurgia , Verapamil/uso terapêutico , Adulto , Idoso , Ablação por Cateter/efeitos adversos , Criança , Estudos de Coortes , Eletrocardiografia Ambulatorial/métodos , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Músculos Papilares/fisiopatologia , Recidiva , Estudos Retrospectivos , Medição de Risco , Taxa de Sobrevida , Taquicardia Ventricular/diagnóstico , Taquicardia Ventricular/tratamento farmacológico , Taquicardia Ventricular/mortalidade , Resultado do Tratamento , Adulto Jovem
8.
Artigo em Inglês | MEDLINE | ID: mdl-27729344

RESUMO

BACKGROUND: The most common form of idiopathic Purkinje-related ventricular tachycardia (VT) is the reentrant type. We describe the clinical and electrophysiological characteristics of focal non-reentrant fascicular tachycardia. METHODS AND RESULTS: Among 530 idiopathic VT patients who were referred for ablation, we identified 15 (2.8%) with non-reentrant fascicular tachycardia (11 men, 45±21 years). Sinus rhythm ECG showed normal conduction intervals with a His-ventricular interval of 41±4 ms. All patients had monomorphic VT (cycle length: 337±88 ms) with a relatively narrow QRS (123±12 ms), and they did not respond to verapamil during the initial presentation. VT exhibited right bundle-branch block/superior axis configuration in 11 patients (73%) and inferior axis in 3 (20%). In 1 patient (7%), VT exhibited left bundle-branch block/superior axis configuration. During ablation, spontaneous VT occurred in 3 patients (20%) and nonentraintable VT or identical premature ventricular complex was induced in 9 (60%). A high-frequency presystolic Purkinje potential was recorded during VT/premature ventricular complex, preceding the QRS by 25±16 ms. VT recurrence was observed in 4 patients (27%), and among them, 3 underwent pacemap-guided ablation during the first session. A second ablation with activation mapping guidance eliminated the VT during the 88±8-month follow-up. CONCLUSIONS: Among idiopathic VT cases referred for ablation, 2.8% were focal non-reentrant fascicular tachycardia, which had distinct clinical characteristics and usually originated from the left posterior fascicle, and less commonly from the left anterior fascicle and right ventricular Purkinje network. Catheter ablation is effective, whereas pacemap-guided approach is less efficacious.


Assuntos
Ablação por Cateter/métodos , Taquicardia Ventricular/fisiopatologia , Taquicardia Ventricular/cirurgia , Fascículo Atrioventricular/fisiopatologia , Bloqueio de Ramo/fisiopatologia , Eletrocardiografia , Técnicas Eletrofisiológicas Cardíacas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ramos Subendocárdicos/fisiopatologia , Recidiva , Resultado do Tratamento , Complexos Ventriculares Prematuros/fisiopatologia
9.
J Arrhythm ; 32(3): 220-2, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27354869

RESUMO

Placement of an implantable cardioverter-defibrillator (ICD) is the only powerful treatment modality for Brugada syndrome in patients presenting with ventricular fibrillation (VF). For those whose first presentation is an electrical storm, pharmacologic therapy is typically used to control VF followed by ICD implantation. We report an alternative approach whereby, before ICD implantation, emergency catheter ablation of the VF-triggering premature ventricular contraction (PVC) resulted in long-term VF-free survival. The results suggest that, because VF triggers appear in a narrow time window, ablation of the culprit PVCs that initiate VF before the index PVCs subside is a reasonable alternative approach.

10.
Heart Vessels ; 31(12): 2035-2044, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26968993

RESUMO

The pro-arrhythmic triggers in Brugada and early repolarization syndromes (BrS, ERS) have not been analyzed systematically except for case reports. We clinically investigated the circumstances which precede/predispose to arrhythmic events in these syndromes during long-term follow-up. A detailed history from the patients/witnesses was taken to investigate the antecedent events in the last few hours that preceded syncope/ventricular fibrillation (VF); medical records, ECG and blood test from the emergency room (ER) were reviewed. 19 patients that fulfilled the investigation criteria were followed up for 71 ± 49 months (34-190 months). Prior to the event (syncope/VF), the patients were partaking different activities in the following decreasing order; drinking alcoholic beverage, having meal, and getting up from sleep, exercise. 3 patients reported mental/physical stress prior to the event and 2 patients developed VF several days after starting oral steroid for treatment of bronchial asthma. In the ER, elevated J-wave amplitude (0.27 ± 0.15 mV) was found with 58 % of the patients having hypokalemia. After electrolyte correction and cessation of steroids, the following day plasma K+ (4.2 ± 0.3 mEq/L, P < 0.001) was significantly increased and J-wave amplitude (0.13 ± 0.1 mV, P < 0.001) was remarkably reduced. Three patients were kept on oral spironolactone/potassium supplements. During follow-up for 71 ± 49 (34-190) months, among 4 patients with VF recurrence, one patient developed VF after taking oral steroid. In ERS and BrS, hypokalemia and corticosteroid therapy add substantial pro-arrhythmic effects, but potentially treatable. Stopping steroid therapy and avoiding hypokalemia had excellent long-term outcome.


Assuntos
Síndrome de Brugada/etiologia , Sistema de Condução Cardíaco/fisiopatologia , Frequência Cardíaca , Síncope/etiologia , Fibrilação Ventricular/etiologia , Potenciais de Ação , Corticosteroides/efeitos adversos , Adulto , Idoso , Antiarrítmicos/uso terapêutico , Biomarcadores/sangue , Síndrome de Brugada/diagnóstico , Síndrome de Brugada/tratamento farmacológico , Síndrome de Brugada/fisiopatologia , Eletrocardiografia , Feminino , Seguimentos , Sistema de Condução Cardíaco/efeitos dos fármacos , Frequência Cardíaca/efeitos dos fármacos , Humanos , Hipopotassemia/sangue , Hipopotassemia/complicações , Hipopotassemia/terapia , Masculino , Pessoa de Meia-Idade , Potássio/sangue , Prognóstico , Estudos Prospectivos , Fatores de Risco , Síncope/diagnóstico , Síncope/tratamento farmacológico , Síncope/fisiopatologia , Fatores de Tempo , Fibrilação Ventricular/diagnóstico , Fibrilação Ventricular/tratamento farmacológico , Fibrilação Ventricular/fisiopatologia , Adulto Jovem
11.
Card Electrophysiol Clin ; 8(1): 115-20, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26920179

RESUMO

The presence of structural heart disease does not exclude fascicular ventricular tachycardia (VT), especially if the VT is verapamil sensitive. An empirical anatomic approach is effective when fascicular VT is noninducible or if diastolic Purkinje potential (P1) cannot be recorded during VT mapping. Pace mapping at the successful ablation site is usually not effective because selective pacing of P1 is difficult and there is an antidromic activation of the proximal P1 potential.


Assuntos
Ablação por Cateter/métodos , Taquicardia Ventricular , Adulto , Eletrocardiografia , Humanos , Masculino , Taquicardia Ventricular/patologia , Taquicardia Ventricular/fisiopatologia , Taquicardia Ventricular/cirurgia , Adulto Jovem
12.
Ann Noninvasive Electrocardiol ; 21(2): 126-35, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26104916

RESUMO

BACKGROUND: The distribution of late gadolinium enhancement (LGE) on the cardiac MRI (CMR) indicates myocardial fibrosis and provides information of possible reentry substrates. QT dynamicity reflecting repolarization abnormalities has gained attention as a potential prognostic predictive factor. OBJECTIVE: To clarify the correlation between the LGE distribution on CMR and QT dynamicity represented by the QT/RR relationship. METHODS: CMR and QT/RR analyses using Holter monitoring were performed in 34 patients (24 males, 60 ± 11 years) with ventricular tachycardia (VT) and/or ventricular fibrillation (VF). The LGE on CMR was scored using a 4-point score in 17 left ventricular segments. The sum of the LGE scores was calculated for each patient. The QT/RR slope and daytime/nighttime QT/RR ratio (day/night ratio) were calculated. The correlation between the slope or the day/night QT/RR ratio and late enhancement findings was analyzed. RESULTS: All patients were divided into 23 LGE positive (LGE(+)) and 11 LGE negative (LGE(-)) patients. The slopes of the QTe/RR and QTa /RR were significantly steeper in the LGE(+) than in LGE(-) patients (0.21 ± 0.03 vs 0.13 ± 0.02; P < 0.001, 0.19 ± 0.03 vs 0.13 ± 0.02; P < 0.001, respectively), and both slopes were significantly correlated with the total LGE scores (r = 0.83, P < 0.001; r = 0.71, P < 0.001, respectively). In the LGE(+) patients, the QTe day/night (1.37 ± 0.38 vs 0.91 ± 0.33; P = 0.002) and QTa day/night ratios (1.33 ± 0.26 vs 1.06 ± 0.30; P = 0.011) were significantly greater than those in the LGE(-) patients. CONCLUSION: The LGE distribution was closely related to the QT dynamicity, suggesting that a combination of these markers can be a powerful tool for understanding the background pathophysiology.


Assuntos
Meios de Contraste , Gadolínio , Aumento da Imagem/métodos , Imageamento por Ressonância Magnética/métodos , Taquicardia Ventricular/diagnóstico por imagem , Fibrilação Ventricular/diagnóstico por imagem , Eletrocardiografia Ambulatorial , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Taquicardia Ventricular/fisiopatologia , Fibrilação Ventricular/fisiopatologia
13.
Magnes Res ; 28(1): 1-13, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25967879

RESUMO

BACKGROUND: Intravenous administration of magnesium (Mg(2+)) is effective for polymorphic ventricular tachycardia via homogenization of transmural ventricular repolarization. Mg(2+) likely plays some role in the heterogeneity of repolarization in J wave syndromes. OBJECTIVE: To investigate the relationship between the repolarization parameters and serum Mg(2+), potassium (K(+)), and calcium (Ca(2+)) levels in J wave syndromes. METHODS: Thirteen J-wave syndrome patients (Brugada and early repolarization [ER] syndromes), with documented episodes of ventricular fibrillation (VF), and 13 ER pattern (ERP) or Brugada type ECG patients were enrolled (25 males, mean age 48 ± 15 years). The 12-lead ECG-derived parameters including the QT, QT dispersion (QTd), Tpeak-Tend (Tp-e) interval, Tp-e dispersion (Tp-ed), Tp-e/QT ratio, and activation recovery interval (ARI) dispersion were calculated; the correlations between these parameters and electrolytes including Mg(2+), K(+), and Ca(2+) were analyzed. RESULTS: Although there was no association between serum K(+) or Ca(2+) and QTd, there was a strong negative correlation between serum Mg(2+) and QTd in J wave syndrome patients with a history of VF (r = -0.715, p = 0.006). Also, there was a tendency for a negative correlation between Mg(2+) and Tp-ed or ARI dispersion in J wave syndrome patients with a history of VF (r = -0.513, p = 0.072 and r = -0.53, p = 0.063, respectively). On the other hand, in 13 patients with a Brugada type ECG or ERP, no correlation was observed between serum Mg(2+) and the QTd, Tp-ed or ARI dispersion. CONCLUSION: Serum Mg(2+) may play an important role in the cardiac repolarization process in J wave syndromes.


Assuntos
Arritmias Cardíacas/sangue , Arritmias Cardíacas/fisiopatologia , Eletrólitos/sangue , Magnésio/sangue , Taquicardia Ventricular/sangue , Taquicardia Ventricular/fisiopatologia , Adulto , Síndrome de Brugada/sangue , Síndrome de Brugada/fisiopatologia , Cálcio/sangue , Eletrocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Potássio/sangue , Síndrome , Fibrilação Ventricular/sangue , Fibrilação Ventricular/fisiopatologia
14.
Europace ; 17(7): 1107-16, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25564550

RESUMO

AIMS: There are many reports on the ECG characteristics of idiopathic outflow tract ventricular arrhythmias (OT-VAs) to predict their origin. However, differentiating near regions using 12-lead ECGs is still complicated. The synthesized 18-lead ECG derived from the 12-lead ECG can provide virtual waveforms of the right-sided chest leads (V3R, V4R, and V5R) and back leads (V7, V8, and V9). The aim of this study was to develop a simple and useful parameter for differentiating OT-VA origins using the 18-lead ECG. METHODS AND RESULTS: We studied 28 and 73 patients with idiopathic VAs in a pacemapping study and validation cohort, respectively. In the pacemapping study, several sites out of five different sites were paced in each patient: the anterior and posterior right ventricular OT (RVOT-ant and RVOT-post), right and left coronary cusps (RCC and LCC), and junction of both cusps (RLJ). The 18-lead ECGs during pacemapping among the five sites were compared for establishing a simple parameter to predict VA origins. A novel parameter using 18-lead ECGs was tested prospectively in 73 patients. In the pacemapping study, the dominant QRS morphology pattern in the synthesized V5R significantly differed among those sites (RVOT-ant:Rs, RVOT-post:rS, RCC:QS, RLJ:qR, and LCC:R). The patients in the validation cohort were divided into five groups depending on those QRS morphology patterns during VAs in the synthesized V5R. Each V5R QRS morphology pattern could predict a precise origin of the OT-VAs with an overall accuracy of 75%. CONCLUSION: The QRS morphology pattern in V5R was a simple and useful parameter for differentiating detailed OT-VA origins.


Assuntos
Algoritmos , Mapeamento Potencial de Superfície Corporal/métodos , Diagnóstico por Computador/métodos , Eletrocardiografia/métodos , Taquicardia Ventricular/diagnóstico , Taquicardia Ventricular/fisiopatologia , Adolescente , Adulto , Idoso , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Adulto Jovem
15.
JACC Clin Electrophysiol ; 1(5): 369-380, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29759464

RESUMO

OBJECTIVES: This study sought to demonstrate the prevalence, mechanism, and electrocardiographic and electrophysiological characteristics of upper septal idiopathic left fascicular ventricular tachycardia (US-ILVT). BACKGROUND: ILVT is classified into left anterior and posterior types with no clear data about US-ILVT. METHODS: Among 193 ILVT patients, we identified 12 patients (6.2%; age 41 ± 22 years, 7 men) with US-ILVT. RESULTS: Of 12 patients with US-ILVT, 6 patients (50%) had previous history of radiofrequency catheter ablation for common ILVT. Sustained VT (cycle length: 349 ± 53 ms) was seen in all patients with a QRS interval slightly wider (104 ± 18 ms) than that during sinus rhythm (90 ± 19 ms). The VT exhibited an identical QRS configuration as sinus rhythm in 6 (50%) and incomplete right bundle branch block configuration in another 6. His-ventricular interval during VT was always shorter than that during sinus rhythm (27 ± 5 ms vs. 47 ± 10 ms). Purkinje potentials were activated in a reverse direction to that of common ILVT; namely, the diastolic potential (P1) was activated retrogradely but the pre-systolic potential (P2) was activated antegradely. At the left upper-middle ventricular septum, P1 potential was recorded during VT, preceding the QRS by 54 ± 20 ms. Radiofrequency catheter ablation at that site eliminated the VT with no recurrence during a 58 ± 35 months of follow-up. CONCLUSIONS: US-ILVT is an identifiable VT that shares common criteria with ILVT and has a narrow QRS interval. Some US-ILVT cases appeared after common ILVT ablation. It is a reverse type of common ILVT (orthodromic form) with baseline morphological abnormalities that might provide a potential substrate for such VT.

16.
J Cardiovasc Electrophysiol ; 25(12): 1376-84, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25329037

RESUMO

INTRODUCTION: We reported impaired QT-rate dependence in early repolarization syndrome (ERS); however, contemporary data have shown peak incidence of sudden cardiac death (SCD) in ERS and Brugada syndrome (BrS) at mid-night and early morning. Taken together, we analyzed the nocturnal QT-rate dependence in both syndromes. METHODS AND RESULTS: A total of 172 subjects were enrolled: 11 ERS, 11 BrS patients, 50 subjects with an uneventful ER pattern (ERP), and 100 non-J-wave control subjects. Ambulatory ECG-derived parameters (QT, QTc, and QT/RR slope) and day-night QT difference were analyzed and compared. Among the groups, there was no significant difference in the average QT or QTc; however, the 24-hour QT/RR slope was significantly smaller in ERS and BrS patients (0.103 ± 0.01 and 0.106 ± 0.01, respectively) than in the control group (0.156 ± 0.03, P < 0.001). Detailed analysis showed a lower day-night QT difference in ERS and BrS patients (19 ±18.7 and 24 ±14 milliseconds, respectively) than in the controls (40 ± 22 milliseconds, P = 0.007) with the lowest QT/RR slopes seen in the ERS and BrS groups from 0 to 3:00 am (QT/RR; 0.076 ± 0.02 vs. 0.092 ± 0.04 vs. 0.117 ± 0.04, for the ERS, BrS, and controls, respectively, P = 0.004) and from 3 to 6 am (QT/RR 0.074 ± 0.03 vs. 0.079 ± 0.02 vs. 0.118 ± 0.04, P < 0.001). CONCLUSION: In a large population of age- and gender-matched groups, both ERS and BrS patients showed attenuated QT-rate dependence and impaired QT day-night modulation that may provide a baseline reentrant substrate. Importantly, QT/RR maladaptation was most evident at mid-night and early morning, which may explain the propensity of such patients to develop SCD during this critical period.


Assuntos
Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/mortalidade , Síndrome de Brugada/diagnóstico , Síndrome de Brugada/mortalidade , Morte Súbita Cardíaca/epidemiologia , Eletrocardiografia Ambulatorial/estatística & dados numéricos , Distribuição por Idade , Ritmo Circadiano , Comorbidade , Feminino , Humanos , Incidência , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Fatores de Risco , Sensibilidade e Especificidade , Distribuição por Sexo , Taxa de Sobrevida
17.
Heart Vessels ; 29(6): 867-72, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24281399

RESUMO

We describe three cases of J-wave syndrome in which ventricular fibrillation (VF) was probably induced by corticosteroid therapy. The patients involved were being treated with prednisolone for concomitant bronchial asthma. One of the three patients had only one episode of VF during her long follow-up period (14 years). Two patients had hypokalemia during their VF episodes. Corticosteroids have been shown to induce various types of arrhythmia and to modify cardiac potassium channels. We discuss the possible association between corticosteroid therapy and VF in J-wave syndrome based on the cases we have encountered.


Assuntos
Antiarrítmicos/administração & dosagem , Reanimação Cardiopulmonar/métodos , Desfibriladores Implantáveis , Glucocorticoides/efeitos adversos , Hipopotassemia , Fibrilação Ventricular , Adulto , Asma/tratamento farmacológico , Eletrocardiografia/métodos , Feminino , Glucocorticoides/administração & dosagem , Humanos , Hipopotassemia/induzido quimicamente , Hipopotassemia/complicações , Hipopotassemia/diagnóstico , Masculino , Síndrome , Resultado do Tratamento , Fibrilação Ventricular/diagnóstico , Fibrilação Ventricular/etiologia , Fibrilação Ventricular/terapia
18.
J Cardiovasc Electrophysiol ; 24(5): 556-61, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23373546

RESUMO

INTRODUCTION: Almost all current investigations on early repolarization syndrome (ERS) have focused on the J-wave characteristics and ST-segment configuration; however, few have reported on ventricular repolarization indexes in ERS. METHODS AND RESULTS: A total of 145 subjects were enrolled: 10 ERS patients, 45 uneventful ER pattern (ERP) subjects, and 90 healthy controls without J waves or ST-segment elevation. Ambulatory ECG-derived parameters (QT, QTc(B), QTc(F), T peak-Tend(Tpe), and QT/RR slope) were measured and statistically compared. Among the groups, there was no significant difference in the average QT and QTc(B); however, ERS patients had the shortest QTc(F) and longest Tpe (QTc(F): 396.2 ± 19 vs 410.4 ± 20 vs 419.2 ± 19 milliseconds, P = 0.036, Tpe: 84.9 ± 12 vs 70.4 ± 11 vs 66.9 ± 15 milliseconds, P < 0.001, for the ERS, ERP, and control groups, respectively). Importantly, the 24-hour QT/RR slope was significantly smaller in the ERS than ERP and control groups (QT/RR: 0.105 ± 0.01 vs 0.154 ± 0.02 vs 0.161 ± 0.03, respectively; P < 0.001). When analyzing the diurnal and nocturnal QT/RR slopes, ERS patients had small diurnal and nocturnal QT/RR slopes while the ERP and control groups had large diurnal and small nocturnal QT/RR slopes (diurnal QT/RR: 0. 077 ± 0.01 vs 0.132 ± 0.03 vs 0.143 ± 0.03, P < 0.001; nocturnal QT/RR: 0.093 ± 0.02 vs 0.129 ± 0.03 vs 0.130 ± 0.04, P = 0.02 in the ERS, ERP, and control groups, respectively). CONCLUSION: ERS patients had a continuously depressed diurnal and nocturnal adaptation of the QT interval to the heart rate. Such abnormal repolarization dynamics might provide a substrate for reentry and be an important element for developing ventricular fibrillation in the ERS cohort.


Assuntos
Arritmias Cardíacas/fisiopatologia , Eletrocardiografia , Adulto , Idoso , Eletrocardiografia Ambulatorial , Feminino , Ventrículos do Coração/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Síndrome , Fibrilação Ventricular/etiologia
19.
Intern Med ; 50(18): 1957-61, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21921376

RESUMO

We describe a case of advanced atrioventricular (AV) block, in which treatment with cilostazol was effective in recovering the AV conduction. The patient was referred to our hospital for close examination of the advanced AV block and permanent pacemaker implantation. Although the patient had experienced third-degree AV block with occasional AV synchrony for more than two days, the AV conduction completely recovered after treatment with oral cilostazol at 200 mg/day. Here we discuss the possible mechanism of the improvement in the AV conduction by cilostazol.


Assuntos
Bloqueio Atrioventricular/tratamento farmacológico , Inibidores da Fosfodiesterase 3/uso terapêutico , Tetrazóis/uso terapêutico , Idoso de 80 Anos ou mais , Bloqueio Atrioventricular/fisiopatologia , Cilostazol , Eletrocardiografia , Feminino , Sistema de Condução Cardíaco/efeitos dos fármacos , Sistema de Condução Cardíaco/fisiopatologia , Humanos , Inibidores da Fosfodiesterase 3/farmacologia , Tetrazóis/farmacologia , Resultado do Tratamento
20.
Intern Med ; 48(17): 1535-9, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19721299

RESUMO

We describe a case of Brugada syndrome, in which recurrent syncope with convulsive seizures was induced after antidepressant treatment. The patient had been treated with five kinds of psychotropic drugs. The twelve-lead ECG after the syncope exhibited an RSR'-pattern in the precordial leads, however, a coved type ST-segment elevation was induced by a pilsicainide test. Although ventricular fibrillation was not induced in the electrophysiologic study, an ICD implantation was considered as the recommended therapy since Brugada syndrome unmasked by antidepressants could not be ruled out. The possible contribution of antidepressants to Brugada type ST-segment changes is discussed.


Assuntos
Antidepressivos Tricíclicos/efeitos adversos , Síndrome de Brugada/induzido quimicamente , Síndrome de Brugada/diagnóstico , Adulto , Síndrome de Brugada/fisiopatologia , Diagnóstico Diferencial , Humanos , Masculino
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