Análise de potenciais tardios em pacientes com arritmias ventriculares malignas / Late potentials analysis in patients with malignant ventricular arrhythmia

PURPOSE--To assess the relationship between late potentials and spontaneous ventricular arrhythmias, organic heart disease, inducibility of arrhythmias at electrophysiological study and ejection fraction. METHODS--The population is comprised by 52 patients (41 men, 11 women with mean age 50 +/- 16 years) with spontaneous clinically documented ventricular tachycardia or ventricular fibrillation. An electrophysiological study was performed with conventional programmed stimulation. Within a week of the test a study of late potentials was also performed. RESULTS--Late potentials were documented in 73 per cent of the patients with ventricular tachycardia and only in 17 per cent of the patients with ventricular fibrillation. Sixty-eight percent of the patients with ischemic cardiopathy presented late potentials and in these, ventricular tachycardia was inducible in 93 per cent . Only one from a group of 7 patients with ventricular arrhythmias and no organic heart disease, presented late potentials. In patients with late potentials, 84 per cent have inducible ventricular tachycardia, but only 26 per cent of patients without late potentials have inducible ventricular tachycardia. The incidence of late potentials was inversely correlated with left ventricular ejection fraction. CONCLUSION--The presence of late potentials was more frequent in patients with ventricular tachycardia than in patients with ventricular fibrillation. The presence of late potentials has a sensibility of 81.5 per cent and a specificity of 78 per cent to detect patients with inducible ventricular tachycardia

Displasia ventricular direita arritmogênica / Arrhythmogenic right ventricular dysplasia

Purpose - To evaluate the clinical findings and complementary investigation to support the diagnosis of arrhythmogenic right ventricular dysplasia.Methods - Six males with a mean age of 40 years old with episodes of sustained ventricular tachycardia with left bundle branch block pattern. All patients were submitted to a clinical investigation, EKG X rays and echocardiograms. In five patients an electrophysiologic study was performed. All patients were treated with anti-arrhythmic drugs. Results - Palpitation was the most common complaint. T-wave inversion in leads V1-V3 was present in 4 patients. An epsilon wave was noted in 2 patients. The chest X ray was abnormal in only 1 patient. All patients had an abnormal echocardiogram, with consisted in the dilatation of the outflow tract of the RV and hypocontractility. In 2 patients aneurysm of the basal RV free wall below tricuspid valva were detected. Ventricular post-excitation waves were present in 4 patients. After a mean follow-up of 37 months, 5 patients were asyntomatic with antiarrhythmic drugs and one in therapeutic adjustment. Conclusion - In patients with ventricular tachycardia with left bundle branch block pattern, the diagnosis of arrhythmogenic right ventricular dysplasia was substantiated by echocardiographic data and electrocardiographic findings such a T-wave inversion during sinus rhythm and ventricular post-excitation waves. The results obtained with anti-arrhythmic drugs in our study group, suggest that drug therapy should be the first and best approach to treat patients with this type of pathology

Comportamento dos potenciais tardios em portadores de infarto do miocárdio submetidos à trombólise coronária / Late potentials in patients with myocardial infarction submitted to thrombolytic therapy

Objetivo­Analisar o comportamento dos potenciais tardios (Pr) em pacientes submetidos com sucesso a trombólise coronária. Casuística e Métodos­Trinta e cinco pacientes com infarto do miocárdio, 32 (91,4%) do sexo masculino com idades entre 33 e 68 (média de 52,6) anos. Trombólise coronária foi obtida durante estudo hemodinâmico através da infusão venosa, em bolo, de doses variáveis de 50,60 e 70mg de rt-PA, sucedida por nova dose de 30mg aos 60 minutos do procedimento. O exame angiocardiográfico foi repetido 12-48h após. O eletrocardiograma de alta resolução foi obtido, utilizando-se sistema ART modelo 1200 EPX, antes, a seguir e 72 horas após o término do estudo hemodinâmico. PT foram reconhecidos pela presença de ondas elétricas com amplitude inferior a 20 microvolts e duração maior que 35ms nos últimos 40ms do complexo QRS (duração total do QRS entre 110 e 114ms)...

Purpose­Analyse the behavior of the late potentials (LP) in patients submitted to thrombolysis with success. Material and Metllods­Thrty-five patients with acute myocardial infarction, 32 (91,4%) male with ages varying from 33 to 68 (mean 52.ó). Thrombolysis was obtained during cinecoronariography with intravenous infusion "in bolus" of d oses of 50mg, 60mg and 70mg of rt-PA, with a new bolus of 30mg at 60 minutes after the procedure. A new angiographic study was performed 12-48 hours late. The high resolution ECG was taken with the ART system model 1200 EPX. before, after and 72 hours later. The presence of electrical activity in the last 40ms of the QRS comple:£ with less than 20 uvolts in amplitude and more than 35ms in duration characterized the LP...