Heart Rate Variability following Cardiac Surgery Fails to Predict Short-Term Cardiovascular Instability

The heart rate variability of 40 patients has been examined by spectral analysis following cardiac surgery. The heart rate variability was measured upon patient arrival in ICU in both a resting supine position, and following passive straight-leg raising. After 12 hours in ICU, the patients were classified as having been cardiovascularly stable or unstable according to a specially devised inventory. Their heart rale variability data was then examined to seek any predictor of instability. Passive straight-leg raising induced a decrease in spectral power across all of the component frequency bands. The LF/HF ratio rose with passive straight-leg raising, but failed to reach significance. None of these changes were sustained. There was no significant difference in heart rate variability patterns between the stable and unstable groups, and so no predictor was identified. Initial clinical assessment was also studied, and it too provided no reliable prediction of short-term cardiovascular instability.

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IDENTIFYING THE CORRELATION BETWEEN ENCEPHALOGRAPHIC SIGNAL IRREGULARITY AND HEART RATE VARIABILITY TO DIFFERENTIATE INTERNALLY AND EXTERNALLY OPERATIVE ATTENTION

Biomedical Engineering Applications Basis and Communications ◽

10.4015/s1016237220500143 ◽

2020 ◽

Vol 32 (02) ◽

pp. 2050014

Author(s):

M. Kumar ◽

D. Singh ◽

K. K. Deepak

Keyword(s):

Heart Rate ◽

Heart Rate Variability ◽

Negative Correlation ◽

Spectral Power ◽

Low Frequency ◽

Significant Negative Correlation ◽

Eeg Signal ◽

Rr Interval ◽

Attention Tasks ◽

Significant Difference

This study identifies a correlation between low-frequency heart rate variability (LF-HRV) and encephalographic (EEG) complexity to differentiate internally operative attention (INT) and externally operative attention (EXT). Electrophysiological fluctuations in response to Posner’s spatial orienting paradigm were explored in 14 healthy volunteers who participated in 6 alternating sessions of attention tasks. HRV analysis was used to measure heart rate fluctuations, and approximate entropy (ApEn) was used to measure changes in the irregularity of EEG and HRV. Power spectral analysis of HRV revealed that there was found to be a significant difference between INT and EXT for HRV-low frequency (HRV-LF) and LH/HF ratio. ApEn for RR-interval time series increased for both attention tasks as compared to baseline and recovery session. The relationship between HRV-LF and EEG spectral power measured at F4 revealed significant negative correlation during ([Formula: see text], with [Formula: see text]) EXT than ([Formula: see text], with [Formula: see text]) INT. Furthermore, a significant positive correlation, yet of moderate strength was noted between HRV-LF and ApEn of EEG signal measured at POz ([Formula: see text], with [Formula: see text]) during EXT as compared to INT ([Formula: see text], with [Formula: see text]) and, a significant negative correlation was observed between ApEn of RR-interval and ApEn of EEG signal measured at POz ([Formula: see text], with [Formula: see text]) during EXT as compared to INT ([Formula: see text], with [Formula: see text]). Thus, it is evident that EXT leads to more irregularity in parietal regions of the brain than the INT. During EXT, the irregularity over the parietal region linked to increased sympathetic activity as compared to INT and corresponds to decreased heart rate. These results may benefit in designing robust human-computer interfaces and accelerated training paradigm to raise an athlete’s performance.

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Power Spectral Analysis of Heart Rate Variability in Patients with Charcot’s Neuroarthropathy

Journal of the American Podiatric Medical Association ◽

10.7547/0960001 ◽

2006 ◽

Vol 96 (1) ◽

pp. 1-8 ◽

Cited By ~ 4

Author(s):

Alexandra Jirkovská ◽

Petr Boucek ◽

Stephanie Wu ◽

Jana Hosová ◽

Robert Bém ◽

...

Keyword(s):

Heart Rate ◽

Heart Rate Variability ◽

Spectral Analysis ◽

Autonomic Neuropathy ◽

Power Spectral Analysis ◽

Short Term ◽

Cardiovascular Reflex ◽

Cardiovascular Reflex Tests ◽

Power Spectral ◽

Significant Difference

Charcot’s or neuropathic osteoarthropathy is one of the most debilitating orthopedic sequelae of diabetes mellitus. Distinguishing Charcot’s neuroarthropathy from clinically similar conditions may be challenging. The neurovascular theory postulates that Charcot’s neuroarthropathy may be secondary to sympathetic denervation of the lower-extremity vasculature. A convenient method for assessing autonomic neuropathy in patients with Charcot’s neuroarthropathy is needed. Short-term power spectral analysis (PSA) of heart rate variability (HRV), a noninvasive and quantitative method for assessing autonomic neuropathy, may be advantageous compared with the traditionally used Ewing’s cardiovascular reflex tests. However, there are limitations to the clinical use of PSA of HRV because of poor standardization. We standardized PSA of HRV and assessed autonomic neuropathy in 17 people with acute Charcot’s neuroarthropathy using PSA of HRV versus Ewing’s tests. More patients with Charcot’s neuroarthropathy were diagnosed as having autonomic neuropathy with PSA of HRV than with Ewing’s tests (94% versus 82%); however, no significant difference between the two methods was found. The results of this study suggest that PSA of HRV requires minimal patient collaboration and time expenditure compared with Ewing’s tests and may be useful in detecting autonomic neuropathy in patients with Charcot’s neuroarthropathy. (J Am Podiatr Med Assoc 96(1): 1–8, 2006)

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The Effect of Heart Rate Variability on Exercise Training Post-Cardiac Surgery

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.440.140 ◽

2013 ◽

Vol 440 ◽

pp. 140-144

Author(s):

Shu Cheng Lin ◽

Ho Cheng Chen ◽

Shu Wang Lin ◽

Wei Chin Hong ◽

Wei Lun Huang ◽

...

Keyword(s):

Heart Rate ◽

Heart Rate Variability ◽

Cardiac Surgery ◽

Exercise Training ◽

Artery Bypass ◽

Analysis Of Covariance ◽

Surgery Patient ◽

Significant Difference ◽

Training Post ◽

Post Cardiac Surgery

Purpose: the purpose of this study was to investigate heart rate variability on exercise training post-cardiac surgery. Method: the data collection was from the Chia-yi Christian Hospital Cardiac Surgery implementation of beating heart coronary artery bypass surgery and valve replacement patients. There were a total of 10 patients included in this study. Cardiac patients after discharge from hospital were the participation of exercise training groups (n=5), and no receiving cardiopulmonary physical therapy of patients was the home-based group (n=5). Statistics: Data analysis was conducted using the SPSS statistical software for Windows 20.0. Analysis of covariance (ANCOVA) was used as the statistical method at a significance level (α) of .05. Through statistical analysis and comparison, the results were obtained as below: In HRV time domain portion, SDNN, CV%, results were significant difference. In frequency domain portion, indices such as LF and VHF, results were significant difference. Conclusion: According to the experimental results, the heart rate variability on exercise training better than patients did not participate in sports training after cardiac surgery patient.

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Non-invasive assessment of short and ultra-short heart rate variability during different physical and physiological tests

Kinesiology ◽

10.26582/k.53.1.15 ◽

2021 ◽

Vol 53 (1) ◽

pp. 122-130

Author(s):

Tuncay Alparslan ◽

Ramiz Arabaci ◽

Recep Gorgulu

Keyword(s):

Heart Rate ◽

Heart Rate Variability ◽

Test Performance ◽

Repeated Measures ◽

Short Term ◽

High Performing ◽

Non Invasive ◽

Significant Difference ◽

Physiological Tests ◽

Data Collection Procedure

The main aim of the present study was to determine the short- and ultra-short-term heart rate variability (HRV) during different physical and physiological tests and to compare HRV to different performance levels. The latter aim was to compare participants’ short- and ultra-short-term heart rate variability before-during-post-tests. Our hypothesis was that there would be a significant difference between test performance and HRV parameters, and the high performing group would have significantly higher HRV parameters than the low performing group. Fifty-three healthy men (Mage=26.9±4 years, Mheight=177.9±5.7 cm; Mweight =77.8±8.7 kg) were recruited in the current study. We completed the data collection procedure for each participant in four consecutive days. On day-1, anthropometric measurements were conducted and then participants performed isokinetic tests. On day-2, participants performed anaerobic tests; on day-3 equilibrium tests, and on day-4 aerobic capacity tests. The HRV records of all participants were obtained before, during and after all these tests. Based on the participants’ performance, they were divided into two groups: participants in G1 had lower performance and those in G2 higher performance. A two-way repeated measures ANOVA yielded significant differences in HRV values obtained in the four different tests. There was a significant difference between fitness test performance and the variation of short- and ultra-short-term HRV parameters. Also, significant differences in HRV values before, during, and after the testing were observed.

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