Effects of Prolonged Spaceflight on Atrial Size, Atrial Electrophysiology, and Risk of Atrial Fibrillation

Htet W. Khine, Katarina Steding-Ehrenborg, Jeffrey L. Hastings, Jamie Kowal, James D. Daniels, Richard L. Page, Jeffery J. Goldberger, Jason Ng, Beverley Adams-Huet, Michael W. Bungo, Benjamin D. Levine

Research output: Contribution to journalArticle

3 Scopus citations

Abstract

BACKGROUND: The prevalence of atrial fibrillation (AF) in active astronauts is ≈5%, similar to the general population but at a younger age. Risk factors for AF include left atrial enlargement, increased number of premature atrial complexes, and certain parameters on signal-averaged electrocardiography, such as P-wave duration, root mean square voltage for the terminal 20 ms of the signal-averaged P wave, and P-wave amplitude. We aimed to evaluate changes in atrial structure, supraventricular beats, and atrial electrophysiology to determine whether spaceflight could increase the risk of AF. METHODS: Thirteen astronauts underwent cardiac magnetic resonance imaging to assess atrial structure and function before and after 6 months in space and high-resolution Holter monitoring for multiple 48-hour time periods before flight, during flight, and on landing day. RESULTS: Left atrial volume transiently increased after 6 months in space (12±18 mL; P=0.03) without changing atrial function. Right atrial size remained unchanged. No changes in supraventricular beats were noted. One astronaut had a large increase in supraventricular ectopic beats but none developed AF. Filtered P-wave duration did not change over time, but root mean square voltage for the terminal 20 ms decreased on all fight days except landing day. No changes in P-wave amplitude were seen in leads II or V1 except landing day for lead V1. CONCLUSIONS: Six months of spaceflight may be sufficient to cause transient changes in left atrial structure and atrial electrophysiology that increase the risk of AF. However, there was no definite evidence of increased supraventricular arrhythmias and no identified episodes of AF.

Original languageEnglish (US)
Pages (from-to)e005959
JournalCirculation. Arrhythmia and electrophysiology
Volume11
Issue number5
DOIs
StatePublished - May 1 2018

Keywords

  • astronauts
  • atrial fibrillation
  • atrial function
  • risk factors
  • spaceflight

ASJC Scopus subject areas

  • Cardiology and Cardiovascular Medicine
  • Physiology (medical)

Fingerprint Dive into the research topics of 'Effects of Prolonged Spaceflight on Atrial Size, Atrial Electrophysiology, and Risk of Atrial Fibrillation'. Together they form a unique fingerprint.

  • Cite this

    Khine, H. W., Steding-Ehrenborg, K., Hastings, J. L., Kowal, J., Daniels, J. D., Page, R. L., Goldberger, J. J., Ng, J., Adams-Huet, B., Bungo, M. W., & Levine, B. D. (2018). Effects of Prolonged Spaceflight on Atrial Size, Atrial Electrophysiology, and Risk of Atrial Fibrillation. Circulation. Arrhythmia and electrophysiology, 11(5), e005959. https://doi.org/10.1161/CIRCEP.117.005959