Cargando…

Effects of acute hypoxia on heart rate variability, sample entropy and cardiorespiratory phase synchronization

BACKGROUND: Investigating the responses of autonomic nervous system (ANS) in hypoxia may provide some knowledge about the mechanism of neural control and rhythmic adjustment. The integrated cardiac and respiratory system display complicated dynamics that are affected by intrinsic feedback mechanisms...

Descripción completa

Detalles Bibliográficos
Autores principales: Zhang, Da, She, Jin, Zhang, Zhengbo, Yu, Mengsun
Formato: Online Artículo Texto
Lenguaje:English
Publicado: BioMed Central 2014
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4059097/
https://www.ncbi.nlm.nih.gov/pubmed/24920347
http://dx.doi.org/10.1186/1475-925X-13-73
_version_ 1782321207150903296
author Zhang, Da
She, Jin
Zhang, Zhengbo
Yu, Mengsun
author_facet Zhang, Da
She, Jin
Zhang, Zhengbo
Yu, Mengsun
author_sort Zhang, Da
collection PubMed
description BACKGROUND: Investigating the responses of autonomic nervous system (ANS) in hypoxia may provide some knowledge about the mechanism of neural control and rhythmic adjustment. The integrated cardiac and respiratory system display complicated dynamics that are affected by intrinsic feedback mechanisms controlling their interaction. To probe how the cardiac and respiratory system adjust their rhythms in different simulated altitudes, we studied heart rate variability (HRV) in frequency domain, the complexity of heartbeat series and cardiorespiratory phase synchronization (CRPS) between heartbeat intervals and respiratory cycles. METHODS: In this study, twelve male subjects were exposed to simulated altitude of sea level, 3000 m and 4000 m in a hypobaric chamber. HRV was assessed by power spectral analysis. The complexity of heartbeat series was quantified by sample entropy (SampEn). CRPS was determined by cardiorespiratory synchrogram. RESULTS: The power spectral HRV indices at all frequency bands depressed according to the increase of altitude. The SampEn of heartbeat series increased significantly with the altitude (P < 0.01). The duration of CRPS epochs at 3000 m was not significantly different from that at sea level. However, it was significantly longer at 4000 m (P < 0.01). CONCLUSIONS: Our results suggest the phenomenon of CRPS exists in normal subjects when they expose to acute hypoxia. Further, the autonomic regulation has a significantly stronger influence on CRPS in acute hypoxia. The changes of CRPS and HRV parameters revealed the different regulatory mechanisms of the cardiac and respiratory system at high altitude.
format Online
Article
Text
id pubmed-4059097
institution National Center for Biotechnology Information
language English
publishDate 2014
publisher BioMed Central
record_format MEDLINE/PubMed
spelling pubmed-40590972014-06-30 Effects of acute hypoxia on heart rate variability, sample entropy and cardiorespiratory phase synchronization Zhang, Da She, Jin Zhang, Zhengbo Yu, Mengsun Biomed Eng Online Research BACKGROUND: Investigating the responses of autonomic nervous system (ANS) in hypoxia may provide some knowledge about the mechanism of neural control and rhythmic adjustment. The integrated cardiac and respiratory system display complicated dynamics that are affected by intrinsic feedback mechanisms controlling their interaction. To probe how the cardiac and respiratory system adjust their rhythms in different simulated altitudes, we studied heart rate variability (HRV) in frequency domain, the complexity of heartbeat series and cardiorespiratory phase synchronization (CRPS) between heartbeat intervals and respiratory cycles. METHODS: In this study, twelve male subjects were exposed to simulated altitude of sea level, 3000 m and 4000 m in a hypobaric chamber. HRV was assessed by power spectral analysis. The complexity of heartbeat series was quantified by sample entropy (SampEn). CRPS was determined by cardiorespiratory synchrogram. RESULTS: The power spectral HRV indices at all frequency bands depressed according to the increase of altitude. The SampEn of heartbeat series increased significantly with the altitude (P < 0.01). The duration of CRPS epochs at 3000 m was not significantly different from that at sea level. However, it was significantly longer at 4000 m (P < 0.01). CONCLUSIONS: Our results suggest the phenomenon of CRPS exists in normal subjects when they expose to acute hypoxia. Further, the autonomic regulation has a significantly stronger influence on CRPS in acute hypoxia. The changes of CRPS and HRV parameters revealed the different regulatory mechanisms of the cardiac and respiratory system at high altitude. BioMed Central 2014-06-11 /pmc/articles/PMC4059097/ /pubmed/24920347 http://dx.doi.org/10.1186/1475-925X-13-73 Text en Copyright © 2014 Zhang et al.; licensee BioMed Central Ltd. http://creativecommons.org/licenses/by/4.0 This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.
spellingShingle Research
Zhang, Da
She, Jin
Zhang, Zhengbo
Yu, Mengsun
Effects of acute hypoxia on heart rate variability, sample entropy and cardiorespiratory phase synchronization
title Effects of acute hypoxia on heart rate variability, sample entropy and cardiorespiratory phase synchronization
title_full Effects of acute hypoxia on heart rate variability, sample entropy and cardiorespiratory phase synchronization
title_fullStr Effects of acute hypoxia on heart rate variability, sample entropy and cardiorespiratory phase synchronization
title_full_unstemmed Effects of acute hypoxia on heart rate variability, sample entropy and cardiorespiratory phase synchronization
title_short Effects of acute hypoxia on heart rate variability, sample entropy and cardiorespiratory phase synchronization
title_sort effects of acute hypoxia on heart rate variability, sample entropy and cardiorespiratory phase synchronization
topic Research
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4059097/
https://www.ncbi.nlm.nih.gov/pubmed/24920347
http://dx.doi.org/10.1186/1475-925X-13-73
work_keys_str_mv AT zhangda effectsofacutehypoxiaonheartratevariabilitysampleentropyandcardiorespiratoryphasesynchronization
AT shejin effectsofacutehypoxiaonheartratevariabilitysampleentropyandcardiorespiratoryphasesynchronization
AT zhangzhengbo effectsofacutehypoxiaonheartratevariabilitysampleentropyandcardiorespiratoryphasesynchronization
AT yumengsun effectsofacutehypoxiaonheartratevariabilitysampleentropyandcardiorespiratoryphasesynchronization