ACUTE EFFECTS OF GANGLION ELECTRICAL STIMULATION ON AUTONOMIC MODULATION AND ENDOTHELIAL FUNCTION IN HEART FAILURE PATIENTS WITH CHAGAS DISEASE: A CONTROLLED AND RANDOMIZED STUDY

Abstract

Transcutaneous electrical nerve stimulation (TENS) has been used as a complementary treatment to improve peripheral blood flow through autonomic modulation. Chagas Disease usually replaces myocardial fibers by fibrosis but usually do not present a severe vascular impairment such as in ischemic etiology, also presents a compensatory overload of the autonomic system. We hypothesized that TENS may reduce sympathetic activity and improve peripheral vascular endothelial function. This study sought to assess sympathetic activity through heart rate variability (HRV) and endothelial function through flow-mediated vasodilation (FMD%) in patients with Chagas disease. Intervention (TENS or placebo) was applied over stellate ganglion region in 20 subjects (10 healthy and 10 chagasic men) for 30 minutes. The HRV were continuously monitored and brachial artery images (FMD) was recorded during at baseline following five minutes after cuff release. The effects of the intervention were compared using ANOVA with Tukey post-hoc test considering a p <0.05. Flow mediated dilation (FMD%) increased from 6.32 ± 2.39% to 10.74 ± 2.52% in healthy men and 8.33 ± 2.44% to 10.7 ± 1.98% in Chagas patients. Heart rate variability (HRV) showed no significant alteration in both sympathetic and parasympathetic modulations. Despite of the no effect over HRV, TENS application over the ganglion region improved peripheral endothelial function measured on brachial artery. This result ratifies the vascular effect of TENS applied over the stellate ganglion and demonstrate the preserved dilatation capacity of the Chagas Disease.View Large Image Figure ViewerDownload Hi-res image Download (PPT)