ABSTRACT
A 8-year-old female patient with refractory incessant atrial tachycardia, very symptomatic and with left ventricular ejection fraction of 0.25. Electrophysiological study and endocardial mapping localized the site of the origin of atrial tachycardia in the superior right atrium. In this site 2 applications of radiofrequency current (25V, 20 and 50 seconds) resulted in termination of the atrial tachycardia. She was discharged off antiarrhythmic drugs and after 2 months ejection fraction was 0.52. She was completely asymptomatic 6 months after ablation procedure
Paciente de 8 anos com história de taquicardia atrial ectópica incessante e refratária a drogas antiarrítmicas, muito sintomática e tendo grande comprometimento da função ventricular, com fração de ejeção de 0,25. A paciente foi submetida a estudo eletrofisiológico e ao mapeamento endocárdico que localizou o foco da taquicardia na regino superior do átrio direito, observando-se precocidade de 40ms do eletrograma nesse local em relação à onda P do eletrocardiograma de superfície. Nesta região foram feitas 2 aplicações de radiofreqüência de 25V com 20 e 50s de duração, com desaparecimento da taquicardia. A paciente evoluiu sem arritmia e após 2 meses a fração de ejeção era de 0,52. Atualmente, encontra-se assintomática após 6 meses de acompanhamento ambulatorial
Subject(s)
Humans , Female , Child , Tachycardia, Ectopic Atrial/surgery , Catheter Ablation/methods , Tachycardia, Ectopic Atrial/diagnosis , Follow-Up Studies , Heart Ventricles/physiopathologyABSTRACT
PURPOSE--To localize the site of the origin of sustained ventricular tachycardia in chronic chagasic cardiomyopathy patients refractory to antiarrhythmic therapy by radionuclide angiography techniques. METHODS--Five patients underwent radionuclide angiography by intravenous administration of 25mCi 99mTc. The images were obtained in sinus rhythm and during sustained ventricular tachycardia induced in the electrophysiologic laboratory for endocardial mapping. Amplitude and phase images were obtained resulting in a contraction wave synchronic to ventricular dispolarization. RESULTS--All patients had haemodynamic stability during the arrhythmia. One patient had incessant ventricular tachycardia. Mean ejection fraction was 0.38. In 4 patients the site of the origin of ventricular tachycardia was posterior and in one it was localized in the interventricular septum. There was identity in the site of the origin of ventricular tachycardia obtained by endocardial mapping or radionuclide angiography in all patients. The therapy was chemical ablation in 3 patients, surgical aneurysmectomy in one and pharmacologic therapy in the last patient. CONCLUSION--The site of the origin of ventricular tachycardia can be estimated by analyzing the contraction wave obtained by radionuclide angiography techniques in patients with hemodynamic stable sustained ventricular tachycardia.
Subject(s)
Humans , Male , Female , Adult , Middle Aged , Tachycardia, Ventricular , Chagas Cardiomyopathy , Electrophysiology , Radionuclide Angiography , Chronic DiseaseABSTRACT
Objetivo: Descrever a experiência inicial do Setor Eletrofisiologia Clínica da Escola Paulista de Medicina com as técnicas de ablaçäo por radiofreqüência. Métodos - Vinte pacientes com arritmias refratárias ao tratamento clínico foram submetidos a estudo eletrofisiológico para diagnóstico e ablaçäo por radiofreqüência dos circuitos de suas arritmias. Dez pacientes eram homens e 10 mulheres com idades variando de 13 a 76 anos (média de 42,4 anos). Dezenove pacientes apresentavam taquiarritmias supraventriculares: 1 taquicardia atrial e 1 fibrilaçäo atrial com resposta ventricular rápida, 5 pacientes com taquicardia reentrante nodal e 12 pacientes com taquicardia reentrante atrioventricular. Um pacientes apresentava taquicardia ventricular de via de saída de ventrículo direito. Resultados - O tempo médio do procedimento foi de 4,17 horas e o número de aplicaçöes variou de 1 a 10 (média de 3,4 aplicaçöes), 30 - 40 V cada. Obteve-se sucesso em 18/20 (90%) dos pacientes, sendo que em 15/18 (83%) dos pacientes tratados com sucesso, o procedimento diagnóstico e terapêutico foi feito só exame. Um paciente apresentou oclusäo arterial aguda relacionada ao procedimento, necessitando de trombectomia por cateter de Fogarty. Durante um seguimento médio de 4 meses nenhum paciente apresentou recorrência de taquicardia. Conclusäo - Os resultados da experiência inicial das técnicas de ablaçäo por radiofreqüencia em nosso meio sugerem que esse proceimento possa beneficiar um grande número de pacientes com taquiarritmias
Purpose - evaluate the efficacy of radiofrequency catheter ablation in patients with refractory cardiac arrhythmias. Methods - Twenty patients with refractory cardinc arrhythmias were undertaken to electrophysiologic studies for diagnosis and radiofrequency catheter ablation of their reentrant arrhythmias. Ten patients were men and 10 women with ages varyingfrom 13 to 76 years (mean = 42,4 years).Nineteen patients had supraventricular tachyarrhythmias: One patient had atrial tachycardia and 1 atrial fibrillation with rapid ventricular rate, 5 patients had reentrant nodal tachycardia, 12 patients had reentrant atrioventricular tachycardia and 1 patient had right ventricular outflow tract tachycardia. Results - the mean time of the procedure was 4,1 hours. The radiofrequency current energy applied was 40-50 V for 30-40 seconds. Ablation was successful in 18/20 (90%) patients; in 15/18 (83%) of sucessfully treated patients the same study was done for diagnosis and radiofrequency ablation. One patient had femoral arterial occlusion and was treated with no significant sequelae. During a mean follow-up of 4 months no preexcitacion or reentrant tachycardia occurred. Conclusions - the results of our experience with radiofrequency catheter ablation of cardiac arrhythmias suggest that this technique can benefit an important number of patients with cardiac arrhythmias