Spaceflight causes thousands of changes in the ways heart cell genes are expressed, but these revert mostly to normal within weeks of being back on Earth
Source:
https://www.newscientist.com/article/2222698-spaceflight-alters-heart-cells-but-they-quickly-recover-back-on-earth/?utm_campaign=RSS%7CNSNS&utm_source=NSNS&utm_medium=RSS&utm_content=home