000087846 001__ 87846
000087846 005__ 20210820090347.0
000087846 0247_ $$2doi$$a10.3389/fphys.2019.01510
000087846 0248_ $$2sideral$$a116236
000087846 037__ $$aART-2019-116236
000087846 041__ $$aeng
000087846 100__ $$0(orcid)0000-0001-5935-9454$$aPalacios, Saúl$$uUniversidad de Zaragoza
000087846 245__ $$aLong-term microgravity exposure increases ECG repolarization instability manifested by low-frequency oscillations of T-Wave vector
000087846 260__ $$c2019
000087846 5060_ $$aAccess copy available to the general public$$fUnrestricted
000087846 5203_ $$aVentricular arrhythmias and sudden cardiac death during long-term space missions are a major concern for space agencies. Long-duration spaceflight and its ground-based analog head-down bed rest (HDBR) have been reported to markedly alter autonomic and cardiac functioning, particularly affecting ventricular repolarization of the electrocardiogram (ECG). In this study, novel methods are developed, departing from previously published methodologies, to quantify the index of Periodic Repolarization Dynamics (PRD), an arrhythmic risk marker that characterizes sympathetically-mediated low-frequency oscillations in the T-wave vector. PRD is evaluated in ECGs from 42 volunteers at rest and during an orthostatic tilt table test recorded before and after 60-day –6° HDBR. Our results indicate that tilt test, on top of enhancing sympathetic regulation of heart rate, notably increases PRD, both before and after HDBR, thus supporting previous evidence on PRD being an indicator of sympathetic modulation of ventricular repolarization. Importantly, long-term microgravity exposure is shown to lead to significant increases in PRD, both when evaluated at rest and, even more notably, in response to tilt test. The extent of microgravity-induced changes in PRD has been associated with arrhythmic risk in prior studies. An exercise-based, but not a nutrition-based, countermeasure is able to partially reverse microgravity-induced effects on PRD. In conclusion, long-term exposure to microgravity conditions leads to elevated low-frequency oscillations of ventricular repolarization, which are potentiated following sympathetic stimulation and are related to increased risk for repolarization instabilities and arrhythmias. Tested countermeasures are only partially effective in counteracting microgravity effects.
000087846 536__ $$9info:eu-repo/grantAgreement/ES/MINECO/DPI2016-75458-R$$9This project has received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement No H2020 638284-MODELAGE$$9info:eu-repo/grantAgreement/EC/H2020/638284/EU/Is your heart aging well? A systems biology approach to characterize cardiac aging from the cell to the body surface/MODELAGE$$9info:eu-repo/grantAgreement/ES/DGA/LMP124-18$$9info:eu-repo/grantAgreement/ES/DGA-FEDER/T39-17R-BSICoS
000087846 540__ $$9info:eu-repo/semantics/openAccess$$aby$$uhttp://creativecommons.org/licenses/by/3.0/es/
000087846 590__ $$a3.367$$b2019
000087846 591__ $$aPHYSIOLOGY$$b20 / 81 = 0.247$$c2019$$dQ1$$eT1
000087846 592__ $$a1.211$$b2019
000087846 593__ $$aPhysiology (medical)$$c2019$$dQ2
000087846 593__ $$aPhysiology$$c2019$$dQ2
000087846 655_4 $$ainfo:eu-repo/semantics/article$$vinfo:eu-repo/semantics/publishedVersion
000087846 700__ $$aCaiani, Enrico G.
000087846 700__ $$aLandreani, Federica
000087846 700__ $$0(orcid)0000-0002-7503-3339$$aMartínez, Juan Pablo$$uUniversidad de Zaragoza
000087846 700__ $$0(orcid)0000-0002-1960-407X$$aPueyo, Esther$$uUniversidad de Zaragoza
000087846 7102_ $$15008$$2800$$aUniversidad de Zaragoza$$bDpto. Ingeniería Electrón.Com.$$cÁrea Teoría Señal y Comunicac.
000087846 773__ $$g10 (2019), 1510 1-12$$pFront. physiol.$$tFRONTIERS IN PHYSIOLOGY$$x1664-042X
000087846 8564_ $$s1818972$$uhttps://zaguan.unizar.es/record/87846/files/texto_completo.pdf$$yVersión publicada
000087846 8564_ $$s28845$$uhttps://zaguan.unizar.es/record/87846/files/texto_completo.jpg?subformat=icon$$xicon$$yVersión publicada
000087846 909CO $$ooai:zaguan.unizar.es:87846$$particulos$$pdriver
000087846 951__ $$a2021-08-20-08:38:28
000087846 980__ $$aARTICLE