Cardiac autonomic modulation and long-term use of amiodarone in patients with chronic Chagasic cardiopathy.

BACKGROUND: Patients with chronic Chagas cardiopathy (CCC), which may be associated with cardiac arrhythmias, frequently use amiodarone, an antiarrhythmic drug that, experimentally, appears to modulate the cardiac autonomic function. OBJECTIVE: The present cross-sectional observational study aimed to evaluate autonomic cardiac modulation in patients with CCC undergoing chronic amiodarone therapy. METHODS: Three groups were investigated: Group 1 included patients with CCC not treated with amiodarone (n = 27); Group 2 included patients with CCC with prolonged use (at least 6 months) of amiodarone (n = 16); and Group 3 included non-Chagasic control patients (n = 23). All patients underwent a complete clinical and laboratory assessment, followed by autonomic function tests, consisting of a basal continuous electrocardiogram in the resting supine position for 10 minutes, followed by a change the orthostatic posture for a further 5 minutes. Heart rate variability (HRV) parameters (median and interquartile interval) were quantified using linear methods in the time- and frequency-domains (autoregressive spectral analysis) and nonlinear methods, including symbolic analysis. RESULTS: Patients with CCC using amiodarone had changes in HRV suggestive of an offset in the sympatho-vagal balance with a vagal modulation predominance (normalized HF, 49.7[27.4] vs 31.1[22.8] [P < 0.05]; and percentage 2V, 40.1 [14.6] vs 21.5 [13.4] [P < 0.05] vs untreated CCC group). These changes were further accompanied by increases in parameters indicative of greater complexity of HRV. CONCLUSIONS: The deviation in the sympatho-vagal balance and the increase in the complexity of HRV strongly suggest that amiodarone may have a cardioprotective effect, in addition to its antiarrhythmic effects, which could increase the survival of these patients.

Massive thymoma of the mid-posterior mediastinum: an unprecedented case in a young adult.

We report an unprecedented case of ectopic thymoma in a young adult. A 33-year-old male presented with a 10-day history of non-productive cough and fever. Investigation revealed mediastinal widening without pulmonary involvement. Computed tomography showed a large mass-14.8 × 10.8 × 8.4 cm-in the mid-posterior mediastinum, and a biopsy obtained by video-assisted thoracoscopy indicated that the mass was a tumor. Immunohistochemistry showed combined thymoma type AB1. Because of the considerable proportions of the tumor and its close proximity to major structures, the patient was treated with chemotherapy.

Apresentamos caso inédito de volumoso timoma ectópico em adulto jovem. Homem de 33 anos de idade, encaminhado com tosse seca e febre diária havia 10 dias. Durante investigação observou-se alargamento mediastinal sem comprometimento pulmonar. Um tumor mediastinal medioposterior, medindo 14,8 × 10,8 × 8,4 cm, foi diagnosticado após tomografia computadorizada e biópsia videotoracoscópica. A imuno-histoquímica revelou timoma misto AB1. Devido à íntima relação com estruturas nobres e grandes proporções, optou-se pela quimioterapia.