Distinctive impaired cardiac autonomic modulation of heart rate variability in chronic Chagas' indeterminate and heart diseases

Vasconcelos, Daniel França

doi:10.1016/j.jelectrocard.2008.10.007

Cited by 19 publications

(32 citation statements)

References 18 publications

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“…Most of the affected subjects remain in this form for their lifetime having excellent long-term prognoses, while showing clinical and functional normality as characterised at the primary diagnostic level by clinical examination, standard electrocardiogram (ECG) and X-rays (Rx) of the heart and digestive tract. However, some chagasics with this form show subtle cardiac functional disturbances detectable by more sophisticated and sensitive exams, such as Doppler echocardiography, 24h ECG, electrophysiological studies and autonomic tests 1,4,[7][8][9][10] .…”

Section: Chagas Disease Essentialsmentioning

confidence: 99%

“…The form involving the heart shows high morbidity and mortality with considerable potential for short-and middle-term disability and poor prognosis in about 30-40% of affected subjects. At the primary level, the diagnosis of cardiac and digestive forms depends on finding alterations in a standard electrocardiogram and radiological signs of enlargement of the digestive tract segments, respectively, independently of the presence of clinical symptoms and signs, but in the presence of positive serology for the disease 1,2,4,10,11,16,[17][18][19] .…”

Section: Chagas Disease Essentialsmentioning

confidence: 99%

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Insights into the clinical and functional significance of cardiac autonomic dysfunction in Chagas disease

Junqueira Junior

2012

Rev. Soc. Bras. Med. Trop.

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INTRODUCTION: Exclusive or associated lesions in various structures of the autonomic nervous system occur in the chronic forms of Chagas disease. In the indeterminate form, the lesions are absent or mild, whereas in the exclusive or combined heart and digestive disease forms, they are often more pronounced. Depending on their severity these lesions can result mainly in cardiac parasympathetic dysfunction but also in sympathetic dysfunction of variable degrees. Despite the key autonomic effect on cardiovascular functioning, the pathophysiological and clinical significance of the cardiac autonomic dysfunction in Chagas disease remains unknown. METHODS: Review of data on the cardiac autonomic dysfunction in Chagas disease and their potential consequences, and considerations supporting the possible relationship between this disturbance and general or cardiovascular clinical and functional adverse outcomes. RESULTS: We hypothesise that possible consequences that cardiac dysautonomia might variably occasion or predispose in Chagas disease include: transient or sustained arrhythmias, sudden cardiac death, adverse overall and cardiovascular prognosis with enhanced morbidity and mortality, an inability of the cardiovascular system to adjust to functional demands and/or respond to internal or external stimuli by adjusting heart rate and other hemodynamic variables, and immunomodulatory and cognitive disturbances. CONCLUSIONS: Impaired cardiac autonomic modulation in Chagas disease might not be a mere epiphenomenon without significance. Indirect evidences point for a likely important role of this alteration as a primary predisposing or triggering cause or mediator favouring the development of subtle or evident secondary cardiovascular functional disturbances and clinical consequences, and influencing adverse outcomes.

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Section: Chagas Disease Essentialsmentioning

confidence: 99%

Section: Chagas Disease Essentialsmentioning

confidence: 99%

Insights into the clinical and functional significance of cardiac autonomic dysfunction in Chagas disease

Junqueira Junior

2012

Rev. Soc. Bras. Med. Trop.

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“…Parasympathetic effects on heart rate, of asymptomatic chagasic patients who are in the indeterminate and cardiac stages of the disease, have been studied under stressful 2,20,27 , and under steady-state conditions 6,24,45 . The findings of these clinical investigations have been conflicting and controversial.…”

Section: Discussionmentioning

confidence: 99%

“…However, we [7][8][9]20,21,37 and other investigators 16 have found that chagasic patients who are in different stages of natural history of the disease may have normal, abnormal 2 or even enhanced responses to conventional cardiac autonomic tests 15,27 . Moreover, the frequency and time domain indexes of parasympathetic modulation may be suppressed in the supine position, but become similar to controls in the standing position and while performing isometric exercise 6,24,27,45 . Since, muscarinic auto-antibodies may behave as positive allosteric modulators of parasympathetic activity 25 ; a diminished high frequency component of heart rate variability 41 and the presence of a slow heart rate 44 could be an indirect expression of the agonist effect.…”

Section: Introductionmentioning

confidence: 92%

Muscarinic antibodies and heart rate responses to dynamic exercise and to the Valsalva maneuver in chronic chagasic patients

Neves¹,

Bacilio²,

Berrueta

et al. 2013

Rev. Inst. Med. trop. S. Paulo

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SUMMARYWe have studied the cardiac chronotropic responses to the Valsalva maneuver and to dynamic exercise of twenty chronic chagasic patients with normal left ventricular function and no segmental wall abnormalities by two-dimensional echocardiogram. The absolute increase in heart rate of the patients (∆ = 21.5 ± 10 bpm, M±SD) during the maneuver was significantly diminished when compared to controls (∆ = 31.30 ± 70, M±SD, p = 0.03). The minimum heart rate (58.24 ± 8.90 vs. 62.80 ± 10, p = 0.68) and the absolute decrease in heart rate at the end of the maneuver (∆ = 38.30 ± 13 vs. ∆ = 31.47 ± 17, p = 0.10) were not different from controls. The initial heart rate acceleration during dynamic exercise (∆ = 12 ± 7.55 vs. ∆ = 19 ± 7.27, M±SD, p = 0.01) was also diminished, but the heart rate recovery during the first ten seconds was more prominent in the sero-positive patients (Median: 14, Interquartile range: (9.75-17.50 vs. 5(0-8.75, p = 0.001). The serum levels of muscarinic cardiac auto-antibodies were significantly higher in the chagasic patients (Median: 34.58, Interquartile Range: 17-46.5, Optical Density) than in controls (Median: 0, Interquartile Range: 0-22.25, p = 0.001) and correlated significantly and directly (r = 0.68, p = 0.002) with early heart rate recovery during dynamic exercise. The results of this investigation indirectly suggest that, the cardiac muscarinic auto-antibodies may have positive agonist effects on parasympathetic heart rate control of chagasic patients.

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“…While some authors could demonstrate impaired autonomic function (Molina, et al, 2006, Vasconcelos & Junqueira, 2009) others could demonstrate that autonomic function was normal in patients without myocardial damage and that abnormalities in autonomic dysfunction was proportional to heart dysfunction, leading these authors to propose that these abnormalities arise as a compensating mechanism for the progressive left ventricular dilatation (Davila, et al, 1991, Davila Spinetti, et al, 1999. These findings led to a new "neurogenic theory", which considers autonomic dysfunction as secondary to ventricular dilatation and hemodynamic alterations, but once installed, acts synergistically with parasitism and inflammation to cause further myocardial damage (Davila, et al, 2004).…”

mentioning

confidence: 99%

Pathogenesis and Pathology of Chagas' Chronic Myocarditis

González¹,

Guerri-Guttenberg²,

Grana³

et al. 2011

Myocarditis

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Distinctive impaired cardiac autonomic modulation of heart rate variability in chronic Chagas' indeterminate and heart diseases

Cited by 19 publications

References 18 publications

Insights into the clinical and functional significance of cardiac autonomic dysfunction in Chagas disease

Insights into the clinical and functional significance of cardiac autonomic dysfunction in Chagas disease

Muscarinic antibodies and heart rate responses to dynamic exercise and to the Valsalva maneuver in chronic chagasic patients

Pathogenesis and Pathology of Chagas' Chronic Myocarditis

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