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Respiratory sinus arrhythmia in Chagas disease
Victor Ribeiro Neves1, Mirja Peltola2, Heikki Huikuri2
1Faculdade de Medicina and Hospital das Clínicas, Universidade Federal de Minas Gerais, Avenida Professor Alfredo Balena, 190-Santa Efigênia, Belo Horizonte, 30130-100 Minas Gerais, Brazil.
Abstract:
We applied the respiratory sinus arrhythmia (RSA) quantification algorithm to 24-hour ECG recordings of Chagas disease (ChD) patients with (G1, n=148) and without left ventricular dysfunction (LVD) (G2, n=33), and in control subjects (G0, n=28). Both ChD groups displayed a reduced RSA index; G1=299 (144-812); G2=335 (162-667), p=0.011, which was correlated with vagal indexes of heart rate variability analysis. RSA index is a marker of vagal modulation in ChD patients.
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