Please use this identifier to cite or link to this item:

Title: Assessment of ventricular repolarization instability in terms of T-wave alternans induced by head-down bed-rest immobilization ( Author submitted manuscript)
Authors: Monasterio, Violeta ORCID RESEARCHERID SCOPUSID
Martín-Yebra, Alba ORCID
Landreani, Federica
Keywords: Microgravity; Head-down bed-rest (HDBR); Ventricular repvolarization; Electrocardiogram (ECG); T wave alternans (TWA); Cardiac arrhythmias
Issue Date: 2019
Publisher: IOP Publishing
Citation: Alba Martín-Yebra et al 2019 Physiol. Meas. 40 104001
Abstract: Objective: To assess the effects of different durations of simulated microgravity exposure on ventricular repolarization (VR) in terms of T-wave alternans (TWA) as well as to test whether an increase in VR heterogeneity could be detected once normal gravity was restored. Approach: A total of 63 healthy volunteers were recruited in several head-down bed-rest (HDBR) experiments in the context of the European Space Agency bed-rest strategy. TWA is evaluated during the night period using ambulatory ECG recordings, before, during and after long- (60 d), mid- (21 d) and short- (5 d) duration HDBR by the long-term averaging technique. Main results: 5-21 d of exposure to simulated microgravity by means of the HDBR model do not lead to a significant increase of cardiac electrical instability in healthy myocardial substrates up to the point of eliciting TWA on the surface ECG. However, TWA indices increased after long-term HDBR exposure, once normal gravity was re-established, indicative of incipient electrical instability on VR at the conclusion of 60 d of HDBR. Significance: The results of this work underline the importance of focusing future research on immediate effects after long-term microgravity exposure, both simulated by HDBR or from space mission scenarios, once partial gravity conditions are re-established. A deeper insight in the understanding of human body reactions in these scenarios results crucial in the design of future long-duration spaceflight missions, to mitigate any potential risk that can limit astronaut's performance.
ISSN: 0967-3334
Appears in Collections:Artículos de revistas

Files in This Item:
File Description SizeFormat 
Assessment of ventricular repolarization instability.pdf1,21 MBAdobe PDFThumbnail

This item is licensed under a Creative Commons License Creative Commons