ECG Holter analysis to detect induced deconditioning on cardiac activity in bedridden volunteers

Abstract Introduction Prolonged bed rest (BR) is an unnatural state, often related to hospitalization, chronic diseases and ageing, inducing reduced functional capacity in multiple body systems, possibly leading to cardiovascular deconditioning. We hypothesized that measuring this decline over time could represent the first step for the formulation of appropriate countermeasures or rehabilitation programs while in the hospital. Accordingly, our aim was to assess the effects of 10-day horizontal BR on cardiac electrical activity. Methods Ten healthy male volunteers (23±5 years) were enrolled in an hospital, after ethical approval and signed consent, to participate to a 10-day strict horizontal BR campaign, preceded and followed by 2 days in the facility, respectively as acclimatization and recovery. The 12-leads 24-hours Holter ECG (1000 Hz, H12+, Mortara Instrument Inc.) was acquired 1 day before BR (PRE), the 5th (BR5) and 10th day (BR10) of bedridden immobilization. From each recording, beat-to-beat RR and QTend interval series, as well as T wave amplitude (Tamp) and upslope (Tslope) were computed. Statistical analysis was applied to test changes induced by BR (ANOVA with Tukey test, p<0.05), separately for day (7:00–23:00) and night (23:00–7:00) periods. Results Daily RR and QTend duration increased during BR, with peak changes at BR5 compared to PRE (+13.3% and +3% respectively), and were still prolonged at BR10 (+12.6% and +2.6%). During the night, while RR increased (BR5:+5.3%; BR10:+1.3%), QTend was found progressively shortened (BR5: −1.6%; BR10: −2.9%). Also, day and night Tamp (BR10: −19.5%) and Tslope (BR10 day: −17.1%; night: −7.8%) were found progressively reduced with the duration of BR. Conclusion During BR, cardiac electrical activity is affected by 10-days bedridden immobilization. Noticeably, a mismatch in RR-QTend relation was visible at night, where vagal autonomic system activity is prevailing. Funding Acknowledgement Type of funding source: Other. Main funding source(s): Agenzia Spaziale Italiana (ASI)

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Computational approaches to understand cardiac electrophysiology and arrhythmias

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.01081.2011 ◽

2012 ◽

Vol 303 (7) ◽

pp. H766-H783 ◽

Cited By ~ 52

Author(s):

Byron N. Roberts ◽

Pei-Chi Yang ◽

Steven B. Behrens ◽

Jonathan D. Moreno ◽

Colleen E. Clancy

Keyword(s):

Ion Channels ◽

Electrical Activity ◽

Cardiac Electrophysiology ◽

Cardiac Activity ◽

Computational Approaches ◽

Cardiac Electrical Activity ◽

Whole Heart ◽

Arrhythmia Therapy ◽

Emergent Behaviors ◽

The Brain

Cardiac rhythms arise from electrical activity generated by precisely timed opening and closing of ion channels in individual cardiac myocytes. These impulses spread throughout the cardiac muscle to manifest as electrical waves in the whole heart. Regularity of electrical waves is critically important since they signal the heart muscle to contract, driving the primary function of the heart to act as a pump and deliver blood to the brain and vital organs. When electrical activity goes awry during a cardiac arrhythmia, the pump does not function, the brain does not receive oxygenated blood, and death ensues. For more than 50 years, mathematically based models of cardiac electrical activity have been used to improve understanding of basic mechanisms of normal and abnormal cardiac electrical function. Computer-based modeling approaches to understand cardiac activity are uniquely helpful because they allow for distillation of complex emergent behaviors into the key contributing components underlying them. Here we review the latest advances and novel concepts in the field as they relate to understanding the complex interplay between electrical, mechanical, structural, and genetic mechanisms during arrhythmia development at the level of ion channels, cells, and tissues. We also discuss the latest computational approaches to guiding arrhythmia therapy.

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Abstract 13292: Comparison of Outcomes Between Pulseless Electrical Activity by Electrocardiography and Pulseless Myocardial Activity by Echocardiography in Out-of-Hospital Cardiac Arrest

Circulation ◽

10.1161/circ.144.suppl_2.13292 ◽

2021 ◽

Vol 144 (Suppl_2) ◽

Author(s):

Romolo Gaspari ◽

Keyword(s):

Cardiac Arrest ◽

Electrical Activity ◽

Primary Outcome ◽

Secondary Analysis ◽

Cardiac Activity ◽

Pulseless Electrical Activity ◽

Secondary Outcome ◽

Shockable Rhythm ◽

Cardiac Electrical Activity ◽

Hospital Cardiac Arrest

Objective: To measure prevalence of discordance between electrical activity recorded by electrocardiography (ECG) and myocardial activity visualized by echocardiography (echo) in patients presenting after cardiac arrest and to compare survival outcomes in cohorts defined by ECG and echo. Methods: This is a secondary analysis of a previously published prospective study at twenty hospitals. Patients presenting after out-of-hospital arrest were included. The cardiac electrical activity was defined by ECG and contemporaneous myocardial activity was defined by bedside echo. Myocardial activity by echo was classified as myocardial asystole- -the absence of myocardial movement, pulseless myocardial activity (PMA)--visible myocardial movement but no pulse, and myocardial fibrillation- -visualized fibrillation. Primary outcome was the prevalence of discordance between electrical activity and myocardial activity. Secondary outcome was survival to hospital discharge. Results: 793 patients and 1943 pauses in CPR were included. 28.6% of CPR pauses demonstrated a difference in electrical activity (ECG) and myocardial activity (echo), 5.0% with asystole (ECG) and PMA (echo), and 22.1% with PEA (ECG) and myocardial asystole (echo). Survival to hospital admission for patients with PMA (echo) was 29.1% (95%CI-23.9-34.9) compared to those with PEA (ECG) (21.4%, 95%CI-17.7-25.6). Twenty-five percent of the 32 pauses in CPR with a shockable rhythm by echo demonstrated a non-shockable rhythm by ECG and were not defibrillated. One of these patients survived, a patient with asystole on ECG and vfib by echo survived because vfib was identified on ECG during a subsequent pause and was defibrillated. Conclusion: Patients in cardiac arrest commonly demonstrate different electrical (ECG) and myocardial activity (echo). Further research is needed to better define cardiac activity during cardiac arrest and to explore outcome between groups defined by electrical and myocardial activity.

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Effect of a Motivational Song on the Autonomic Nervous System and the Heart of Indian Male Volunteers

Advances in Medical Technologies and Clinical Practice - Design and Development of Affordable Healthcare Technologies ◽

10.4018/978-1-5225-4969-7.ch015 ◽

2018 ◽

pp. 299-317 ◽

Cited By ~ 1

Author(s):

Gitika Yadu ◽

Suraj Kumar Nayak ◽

Debasisha Panigrahi ◽

Sirsendu Sekhar Ray ◽

Kunal Pal

Keyword(s):

Heart Rate ◽

Nervous System ◽

Autonomic Nervous System ◽

Electrical Activity ◽

Stimulus Condition ◽

Cardiac Activity ◽

Ecg Signals ◽

Autonomic Nervous ◽

Cardiac Electrical Activity ◽

Hrv Analysis

This chapter investigates the effect of a motivational song (stimulus) on the physiology of the autonomic nervous system and the electrical activity of the heart. Five min electrocardiogram (ECG) signals were acquired from 19 volunteers during the resting and the post-stimulus conditions. The RR intervals (RRIs) were extracted. Recurrence analysis of the RRI time series indicated a higher alteration (acceleration or deceleration) in the heart rate along with the reduction of the causality and patterned behavior of the RRIs. The exact alteration in the ANS physiology was examined using heart rate variability (HRV) analysis. The results of the HRV analysis suggested an increase in the parasympathetic activity in the post-stimulus condition. The alteration in the cardiac activity was analyzed using time domain and joint time-frequency domain analyses of ECG signals. The results suggested an alteration in the cardiac electrical activity of the heart in the post-stimulus condition.

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Theoretical analysis of T-wave polarity based on a model of cardiac electrical activity

Journal of Electrocardiology ◽

10.1016/s0022-0736(78)80110-1 ◽

1978 ◽

Vol 11 (2) ◽

pp. 171-180 ◽

Cited By ~ 6

Author(s):

Michitoshi Inoue ◽

Masatsugu Hori ◽

Fumihiko Kajiya ◽

Hideo Kusuoka ◽

Hiroshi Abe ◽

...

Keyword(s):

Theoretical Analysis ◽

Electrical Activity ◽

T Wave ◽

Cardiac Electrical Activity

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The Role of Computer Modeling in Electrocardiography

Methods of Information in Medicine ◽

10.1055/s-0038-1634809 ◽

1990 ◽

Vol 29 (04) ◽

pp. 282-288 ◽

Cited By ~ 2

Author(s):

A. van Oosterom

Keyword(s):

Electrical Activity ◽

Computer Modeling ◽

Body Surface ◽

Electrical Current ◽

The Body ◽

Volume Conductor ◽

Current Generator ◽

Cardiac Electrical Activity ◽

Source Models

AbstractThis paper introduces some levels at which the computer has been incorporated in the research into the basis of electrocardiography. The emphasis lies on the modeling of the heart as an electrical current generator and of the properties of the body as a volume conductor, both playing a major role in the shaping of the electrocardiographic waveforms recorded at the body surface. It is claimed that the Forward-Problem of electrocardiography is no longer a problem. Several source models of cardiac electrical activity are considered, one of which can be directly interpreted in terms of the underlying electrophysiology (the depolarization sequence of the ventricles). The importance of using tailored rather than textbook geometry in inverse procedures is stressed.

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