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Linear and nonlinear analysis of heart rate variability in coronary disease
Victor Ribeiro Neves1, Anielle Cristhine Medeiros Takahashi, Michele Daniela Borges do Santos-Hiss
1Laboratory of Cardiovascular Physiotherapy, Nucleus of Research in Physical Exercise, Federal University of São Carlos (UFSCar), Via Washington Luiz, Km 235, São Carlos, SP 13565-905, Brazil.
Insights
Heart rate variability (HRV) analysis showed no significant differences between coronary artery disease (CAD) patients with or without acute myocardial infarction (AMI) and healthy controls. This finding may be influenced by medical treatments and exercise capacity.
Area of Science:
- Cardiology
- Biomedical Engineering
- Physiology
Background:
- Coronary artery disease (CAD) and acute myocardial infarction (AMI) are linked to reduced heart rate variability (HRV).
- Assessing cardiac autonomic modulation is crucial for understanding cardiovascular health.
- Linear and nonlinear HRV analyses offer complementary insights into autonomic function.
Purpose of the Study:
- To compare heart rate variability (HRV) in patients with coronary artery disease (CAD) with and without acute myocardial infarction (AMI) against healthy controls.
- To evaluate cardiac autonomic modulation using both linear (spectral analysis) and nonlinear (Shannon entropy, conditional entropy, symbolic analysis) methods.
- To investigate potential differences in HRV parameters indicative of sympathetic and vagal modulation across the groups.
Main Methods:
- Fifty-eight men were categorized into three groups: healthy (n=19), CAD (n=20), and CAD-AMI (n=19).
- Resting RR intervals were recorded for 10 minutes using a Polar S810i HR monitor.
- Linear and nonlinear HRV analyses were performed, including spectral analysis, Shannon entropy (SE), conditional entropy (CE), and symbolic analysis (SA) patterns (0V, 2ULV).
Main Results:
- No significant differences in linear or nonlinear HRV parameters were observed among the healthy, CAD, and CAD-AMI groups.
- The CAD group exhibited higher body mass index and weight compared to the CAD-AMI group.
- Specific symbolic analysis patterns (0V, 2ULV) showed significant correlations with SE, CI, and NCI across all groups.
Conclusions:
- Cardiac autonomic modulation, assessed by linear and nonlinear HRV methods, did not differ significantly between the studied groups.
- Factors such as beta-blocker use, prior coronary angioplasty, and the exercise capacity of healthy individuals may explain the lack of observed differences.
- Further research is needed to elucidate the complex interplay of these factors on HRV in cardiovascular disease.
Objective:
Coronary artery disease (CAD) and acute myocardial infarction (AMI) are associated with a reduction of heart rate variability (HRV). The aim of this study was to compare the HRV of CAD patients with and without AMI (CAD-AMI) with health-matched controls by linear (spectral analysis) and nonlinear [Shannon entropy (SE), conditional entropy (CE) and symbolic analysis (SA)] analysis.
Methods:
Fifty-eight men were divided into three groups: healthy (n = 19, 57 ± 4 years), CAD (n = 20, 56 ± 10 years) and CAD-AMI (n = 19, 54 ± 12 years). The RR intervals were recorded at rest in the supine position for 10 min with an HR monitor (Polar(®)S810i). A series of 250 beats was selected to analyze variance, spectral analysis, SE, CE [complexity index (CI), normalized CI (NCI)] and SA (0V, 1V, 2LV and 2ULV patterns), as well as 0V (no significant variation) and 2ULV (two significant unlike variations), which reflect sympathetic and vagal modulation, respectively. One-way ANOVA (or the Kruskal-Wallis test when appropriate) and Pearson correlation were used.
Results:
The CAD group had higher body mass index and weight than the CAD-AMI group, but no differences were found between the healthy and AMI groups. There were no differences between the groups regarding linear and nonlinear analysis. The 0V and 2ULV patterns were significantly correlated with the SE, CI and NCI of the three groups.
Interpretation:
There was no difference between the groups regarding cardiac autonomic modulation by linear and nonlinear methods, which may be due to beta-blocker use, coronary angioplasty and the exercise capacity of healthy subjects.
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