RESUMO
BACKGROUND: There is some disagreement concerning the minimal value of the interval between components of double potentials (DPs interval) that allows distinguishing complete and incomplete block in the cavotricuspid isthmus (CTI). OBJECTIVES: To assess clinical utility of the relationship between atrial flutter cycle length (AFL CL) and the DPs interval. METHODS: Ablation of the CTI was performed in 87 patients during AFL (245 ± 40 ms). Subsequently, DPs were recorded during proximal coronary sinus pacing at sites close to a gap in the ablation line and after achievement of complete isthmus block. RESULTS: We noted strong correlation between AFL CL and the DPs interval after achievement of isthmus block (r = 0.73). The mean DPs interval was 95.3 ± 18.3 ms (range 60-136 ms) and 123.3 ± 24.3 ms (range 87-211 ms) during incomplete and complete isthmus block, respectively (P < 0.001). When expressed as a percentage of AFL CL, this interval was 35.7 ± 3.5% AFL CL (range 28-40.2%) and 50.4 ± 6.9% AFL CL (range 39-72%) during incomplete and complete isthmus block, respectively (P < 0.001). A cutoff value of 40% of AFL CL identified CTI block with 96.7% sensitivity and 100% specificity. CONCLUSIONS: The interval between DPs after achievement of block in the CTI correlates with AFL CL. The DPs interval expressed as a percentage of AFL CL allows better distinguishing between complete and incomplete isthmus block compared to standard method based on milliseconds. The DPs interval below 40% of AFL CL indicates sites close to a gap in the ablation line.
Assuntos
Flutter Atrial/cirurgia , Ablação por Cateter/métodos , Adulto , Idoso , Flutter Atrial/fisiopatologia , Seio Coronário/fisiopatologia , Seio Coronário/cirurgia , Técnicas Eletrofisiológicas Cardíacas/métodos , Feminino , Bloqueio Cardíaco/fisiopatologia , Bloqueio Cardíaco/cirurgia , Sistema de Condução Cardíaco/fisiopatologia , Sistema de Condução Cardíaco/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Valva Tricúspide/fisiopatologia , Valva Tricúspide/cirurgiaRESUMO
AIMS: The goal of this study was to describe mapping and ablation of severe arrhythmias during pregnancy, with minimum or no X-ray exposure. Treatment of tachyarrhythmia in pregnancy is a clinical problem. Pharmacotherapy entails a risk of adverse effects and is unsuccessful in some patients. Radiofrequency ablation has been performed rarely, because of fetal X-ray exposure and potential maternal and fetus complications. GROUP AND METHOD: Mapping and ablation was performed in 9 women (age 24-34 years) at 12-38th week of pregnancy. Three had permanent junctional reciprocating tachycardia, and 2 had incessant atrial tachycardia. Four of them had left ventricular ejection fraction < or =45%. One patient had atrioventricular nodal reciprocating tachycardia requiring cardioversion. Three patients had Wolff-Parkinson-White syndrome. Two of them had atrial fibrillation with ventricular rate 300 bpm and 1 had atrioventricular tachycardia 300 bpm. Fetal echocardiography was performed before and after the procedure. RESULTS: Three women had an electroanatomic map and ablation done without X-ray exposure. The mean fluoroscopy time in the whole group was 42 +/- 37 seconds. The mean procedure time was 56 +/- 18 minutes. After the procedure, all women and fetuses were in good condition. After a mean period of 43 +/- 23 months follow up (FU), all patients were free of arrhythmia without complications related to ablation either in the mothers or children. CONCLUSION: Ablation can be performed safely with no or minimal radiation exposure during pregnancy. In the setting of malignant, drug-resistant arrhythmia, ablation may be considered a therapeutic option in selected cases.
Assuntos
Antiarrítmicos/uso terapêutico , Arritmias Cardíacas/cirurgia , Ablação por Cateter , Complicações Cardiovasculares na Gravidez/cirurgia , Adulto , Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/tratamento farmacológico , Ablação por Cateter/efeitos adversos , Resistência a Medicamentos , Técnicas Eletrofisiológicas Cardíacas , Europa (Continente) , Feminino , Fluoroscopia , Idade Gestacional , Humanos , Gravidez , Complicações Cardiovasculares na Gravidez/diagnóstico , Complicações Cardiovasculares na Gravidez/tratamento farmacológico , Doses de Radiação , Medição de Risco , Índice de Gravidade de Doença , Austrália do Sul , Taquicardia Reciprocante/cirurgia , Taquicardia Supraventricular/cirurgia , Falha de Tratamento , Ultrassonografia Doppler , Ultrassonografia Pré-Natal , Síndrome de Wolff-Parkinson-White/cirurgia , Adulto JovemRESUMO
We describe a 42-year-old professional driver with hypertension, obesity and recurrent episodes of highly symptomatic typical atrial flutter. Despite chronic sotalol treatment, 1:1 AV conduction with RBBB-morphology was observed. After excluding of thrombus in the heart chambers, the 'urgent' and successful RF ablation was performed.
Assuntos
Flutter Atrial/cirurgia , Condução de Veículo , Ablação por Cateter/métodos , Adulto , Antiarrítmicos/administração & dosagem , Flutter Atrial/complicações , Flutter Atrial/tratamento farmacológico , Eletrocardiografia , Técnicas Eletrofisiológicas Cardíacas , Sistema de Condução Cardíaco/fisiopatologia , Humanos , Hipertensão/complicações , Masculino , Obesidade/complicações , Recidiva , Sotalol/administração & dosagem , Resultado do TratamentoRESUMO
INTRODUCTION: Measuring the postpacing interval (PPI) and correcting for the tachycardia cycle length (TCL) is an important entrainment response (ER). However, it may be impossible to measure PPI due to electrical noise on the mapping catheter. To overcome this problem, 2 alternative methods for the assessment of ER have been proposed: N+1 difference (N+1 DIFF) and PPIR method. PPI-TCL difference (PPI-TCL) correlates very well with ER assessed by new methods, but the agreement with PPI-TCL was established only in relation to PPIR method. Moreover, it is not known which of these methods is superior in the assessment of ER. METHODS: We analyzed 155 episodes of ER in 21 patients with heterogeneous reentrant arrhythmias. ER was estimated by PPI-TCL and by both alternative methods. Agreement between methods was assessed by means of the Bland-Altman test, kappa coefficient (kappa), and correlation coefficient (r). Finally, a mathematical comparison of the alternative methods was performed. RESULTS: The agreement between PPI-TCL and alternative methods was very good. For N+1 DIFF the mean difference was -1.86 +/- 7.31 ms; kappa = 0.9; r = 0.98; for PPIR method the mean difference was -1.46 +/- 7.65 ms; kappa = 0.92; r = 0.99. Agreement between both alternative methods was also very high: the mean difference of 0.5 +/- 6.6 ms; kappa = 0.89; r = 0.99. The analysis of the equations used for calculation of ER by these methods revealed that essentially they were mathematically equivalent. CONCLUSION: Each of the alternative methods may be used for evaluation of ER when PPI-TCL cannot be assessed directly. Results obtained by both alternative methods are comparable.
Assuntos
Estimulação Cardíaca Artificial , Eletrocardiografia , Técnicas Eletrofisiológicas Cardíacas , Modelos Cardiovasculares , Taquicardia Reciprocante/diagnóstico , Taquicardia Reciprocante/terapia , Adulto , Idoso , Artefatos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Fatores de Tempo , Resultado do TratamentoRESUMO
We present a case of 53-year-old patient who experienced paroxysms of wide QRS complex tachycardia at a rate of 150 bpm and LBBB morphology 6 years after inferior myocardial infarction and CABG. Anamnesis and morphology of tachycardia could suggest ventricular tachycardia. However during electrophysiological study we observed AVRT with LBBB and "regularly irregular" AVRT with normal QRS complex and changing entrance to the AV node (through slow and fast pathway). In this paper we present our approach and try to explain why the tachycardia using concealed bypass tract appeared so late in life.
Assuntos
Bloqueio de Ramo/diagnóstico , Ponte de Artéria Coronária/efeitos adversos , Eletrocardiografia , Infarto do Miocárdio/complicações , Taquicardia Paroxística/diagnóstico , Bloqueio de Ramo/etiologia , Ablação por Cateter , Técnicas Eletrofisiológicas Cardíacas , Sistema de Condução Cardíaco , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/cirurgia , Taquicardia Paroxística/etiologia , Taquicardia Paroxística/terapiaRESUMO
We present a case of a 19-year-old patient with incessant arrhythmias originating from the right upper pulmonary vein (RUPV) presenting as frequent premature beats, automatic rhythms mimicking sinus rhythm (SR) and pulmonary vein tachycardias. Morphology of P' wave resembled sinus P wave due to relatively short distance of the ectopic focus from the sinus node. Occasionally, when discharges from the focus were relatively slow (800-500 ms) and regular it was mimicking sinus rhythm. Activation preceding P' wave during arrhythmia was recorded in RUPV as well as in superior vena cava. In this paper we discuss our approach that allowed localising the arrhythmogenic focus in the RUPV. After isolation of the RUPV sinus rhythm was restored with tachycardia at a cycle length of 320 ms continuing in the isolated vein.
Assuntos
Fibrilação Atrial/cirurgia , Complexos Atriais Prematuros/cirurgia , Ablação por Cateter/métodos , Técnicas Eletrofisiológicas Cardíacas/métodos , Veias Pulmonares/cirurgia , Taquicardia Atrial Ectópica/cirurgia , Adulto , Fibrilação Atrial/fisiopatologia , Complexos Atriais Prematuros/fisiopatologia , Bradicardia/fisiopatologia , Bradicardia/cirurgia , Eletrocardiografia/métodos , Eletrofisiologia/métodos , Humanos , Masculino , Veias Pulmonares/fisiopatologia , Taquicardia Atrial Ectópica/fisiopatologia , Resultado do TratamentoRESUMO
Recent studies have demonstrated spatio-temporal organisation in atrial fibrillation (AF), with a highest dominant frequencies (DF) at pulmonary veins ostia (PVo). We present a case of 58-year-old woman with AF evaluated by spectral frequency analysis. Simultaneous recordings at each veno-atrial junction and coronary sinus were obtained. Sequential fast Fourier transforms (FFT) of digitalized signals were performed. FFT profiles were analysed to determine DF. Low DF recorded at right inferior PVo suggested no contribution to AF process. Ablation of high DF PVo and low DF SVC with nonuniform anisotropic conduction resulted in AF termination and good clinical outcome in 1-year follow-up.