Influência da fibrilação atrial na história natural da cardiomiopatia hipertrófica / The Influence of Atrial Fibrillation in the Natural History of Hypertrophic Cardiomyopathy

PURPOSE--To evaluate the influence of atrial fibrillation in the natural history of hypertrophic cardiomyopathy. METHODS--Eighty-eight patients under ambulatory treatment were studied. Most of them presented the asymmetric type of hypertrophic cardiomyopathy (87.5 per cent). Group I (77 cases) was formed by patients who had never had atrial fibrillation and group II (11 cases) by those who had this arrhythmia paroxysmal or established. RESULTS--In group I, with ages 48.02 +/- 14.82 years, left atrial dimensions 4.21 +/- 0.66 cm, there was one sudden death; 69 were treated by clinical means and 7 by surgery; no patient developed thromboembolism neither cardiac failure. In group II, with ages 58.02 +/- 11.04 years and left atrial dimension 5.32 +/- 0.45 cm, there were 4 deaths, 4 thromboembolisms and 3 with cardiac failure; all received only clinical treatment, having improved in clinical status in 71.42 per cent after amiodarone therapy. CONCLUSION--Atrial fibrillation was present in 12.5 per cent, mostly in the asymmetric type, and in patients after 5th decade, all of them with enlarged left atrium (> 4.7 cm), with highest morbidity (thromboembolism and cardiac failure) and mortality. Among the survivors, amiodarone therapy improved functional class in 71.42 per cent

Avaliaçäo da síncope em pacientes com cardiopatia chagásica crônica / Evaluation of syncope in patients with Chagas heart disease chronic

Objetivo Avaliar a síncope em pacientes com cardiopatia chagásica crônica associada a distúrbios da condução intraventricular. Métodos Nove pacientes, idade média de 49 anos, sendo 7 do sexo masculino. O estudo consistiu de eletrograma do feixe de His, determinação do período Wenckebach (PW) da condução atrioventricular, tempo de recuperação atrioventricular, tempo de recuperação do nó sinusal (TRNS), estabilidade atrial e estimulação ventricular programada (EVP). Resultados Taquicardia ventricular (TV) monomórfica foi induzida em cinco pacientes (55,5%). Depressão do PW foi observada em três (33,8%) e o TRNS foi normal em todos. Em um caso o estudo eletrofisiológico (EEF) foi inteiramente normal. Dos cinco casos de TV induzida, em seguimento médio de sete meses, um faleceu subitamente, três tornaram-se assintomáticos com o uso de antiarrítmicos e um foi encaminhado para tratamento não farmacológico. Dos quatro pacientes restantes, com acompanhamento médio de 21 meses, três estão assintomáticos e um apresenta tonteiras eventuais (paciente com estudo normal). Dos cinco indivíduos com TV, quatro apresentavam síncope recorrente, enquanto que dos quatro sem TV, todos tiveram um único episódio de síncope. Conclusão Nos pacientes com distúrbio de condução intraventricular, cardiopatia chagástica e síncope, TV pode ser responsável pelo sintoma em aproximadamente 44% dos casos. A EVP deve ser considerada como rotina na avaliação destes pacientes.

Purpose To evaluate causes of syncope in patients with Chagas disease and intraventricular conduction disturbances. Methods Nine patients have been studied, being sevem males. Average of 49 years. The studied consisted of His Bundle electrogram, determination of Wenckebach period (WP), sinus node recovery time (SNRT), atrial stability and programmed ventricular stimulation (PVS).Results — Monomorphic ventricular tachycardia (VT) was induced in fave patients (55.5%), WP depression was observed in three cases, H-V interval prolongation occurred in three cases and the SNRT was normal in hall patients. In one case the electrophysiological study was completely normal. Among five patients with induced VT, with a mean follow-up period of seven months, one died suddenly, three became assymptomatic with antiarrhithmic drugs and one went on a non pharmacological therapy. In the other four patients with a mean follow-up period of 21 months, three are assymptomatic and one presents occasional dizziness (patient with a normal study). Among the patients with VT four presented recurrent syncope while in the group of patients without VT (four patients) all had only one syncopal episode.Conclusion Patients with intraventricular disturbances, Chagas disease and syncope, VT may be responsible for the symptoms in approximately 44% of cases. The PVS must be considered as a routine in the investigation of these patients.

Historia natural del bloqueo auriculoventricular de tercer grado en la miocarditis chagásica crónica / Natural history of the auriculoventricular block of third grade in the chronic chagasic myocarditis

Presenta un estudio basado en la revisión de 380 electrocardiogramas de 103 enfermos con miocarditis chagásica crónica y bloqueo auriculaventricular de tercer grado, 93 de los cuales fallecieron por insuficiencia cardíaca, arritmias graves y paro cardíaco. Se busca una posible explicación para la larga supervivencia observada, agrupándose a los enfermos fallecidos, en tres grupos, según hayan tenido una sobrevida de entre 3 meses a 5 años, de 5 a 20 años, y, de 20 a 30 o más; observándose en los enfermos restantes una sobrevida de entre 8 meses y 16 años, con 5 meses de evolución. Se observaron tres fases en el tiempo de sobrevida de los enfermos: una, inicial, que puede corresponder a las primeras semanas o meses de asistencia médica; una segun da, media, en que se presentan síntomas variables y algunas limitaciones en la actividad de los enfermos, y, la final, en que se apresentan síntomas importantes y se requiere hospitalización. Analiza ejemplos de alteraciones electrocardiográficas en las distintas fases de evolución y los possibles mecanismos idioventriculares de comandos y de escapas en cada una de las combinaciones de morfología de bloqueos