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Heart rate variability as a biomarker in patients with Chronic Chagas Cardiomyopathy with or without concomitant
Luiz Eduardo Virgilio Silva1, Henrique Turin Moreira1, Marina Madureira de Oliveira1
1Division of Cardiology, Department of Internal Medicine, Ribeirão Preto Medical School, University of São Paulo, Av. Bandeirantes, 3900, Ribeirão Preto, São Paulo, 14048-900, Brazil.
Insights
Heart rate variability (HRV) analysis helps predict Chagas heart disease (CCC) prognosis. Increased heart rate fragmentation indicates a worse outlook, especially in patients with digestive involvement.
Area of Science:
- Cardiology
- Autonomic Nervous System Research
- Medical Data Analysis
Background:
- Dysautonomia contributes to Chronic Chagas Cardiomyopathy (CCC) pathogenesis and digestive issues.
- Heart rate variability (HRV) is crucial for risk stratification in CCC.
- Investigating HRV differences in isolated CCC versus mixed (CCC + digestive) forms is essential.
Purpose of the Study:
- To assess HRV's ability to stratify death risk in CCC patients.
- To compare HRV alterations in isolated CCC versus mixed CCC forms.
- To develop machine learning models for CCC risk prediction.
Main Methods:
- 31 CCC patients were categorized into low, intermediate, and high-risk groups based on Rassi score.
- 10-20 minute single-lead ECGs were recorded to generate RR series and calculate 31 HRV indices.
- Four machine learning models were developed to predict patient risk class.
Main Results:
- High-risk CCC patients showed decreased phase entropy and increased inflection points compared to low-risk.
- Mixed form patients exhibited reduced RR histogram triangular interpolation and low-frequency power.
- Support vector machine model achieved the highest predictive accuracy (F1-score of 0.61).
Conclusions:
- The mixed form of Chagas disease is linked to diminished slow HRV components.
- Worse CCC prognosis correlates with increased heart rate fragmentation.
- Combining HRV indices improves risk stratification accuracy; mixed form may involve sympathetic and parasympathetic impairment.
Background:
Dysautonomia plays an ancillary role in the pathogenesis of Chronic Chagas Cardiomyopathy (CCC), but is the key factor causing digestive organic involvement. We investigated the ability of heart rate variability (HRV) for death risk stratification in CCC and compared alterations of HRV in patients with isolated CCC and in those with the mixed form (CCC + digestive involvement). Thirty-one patients with CCC were classified into three risk groups (low, intermediate and high) according to their Rassi score. A single-lead ECG was recorded for a period of 10-20 min, RR series were generated and 31 HRV indices were calculated. The HRV was compared among the three risk groups and regarding the associated digestive involvement. Four machine learning models were created to predict the risk class of patients.
Results:
Phase entropy is decreased and the percentage of inflection points is increased in patients from the high-, compared to the low-risk group. Fourteen patients had the mixed form, showing decreased triangular interpolation of the RR histogram and absolute power at the low-frequency band. The best predictive risk model was obtained by the support vector machine algorithm (overall F1-score of 0.61).
Conclusions:
The mixed form of Chagas' disease showed a decrease in the slow HRV components. The worst prognosis in CCC is associated with increased heart rate fragmentation. The combination of HRV indices enhanced the accuracy of risk stratification. In patients with the mixed form of Chagas disease, a higher degree of sympathetic autonomic denervation may be associated with parasympathetic impairment.
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