A new study says that long exposure to the microgravity of outer space can change the shape of astronauts' hearts, resulting in an increased risk of cardiovascular issues.
The research allows scientists to understand the effects that spaceflight for 18 months or longer could have on the health of astronauts' hearts, according to AniNews.
Researchers looked at data collected from 12 astronauts before, during, and after they were working on the International Space station. They found that the heart took a 9.4 percent more spherical form due to long exposure, International Business Times reported.
"The heart doesn't work as hard in space, which can cause a loss of muscle mass," said James Thomas, lead scientist for ultrasound at NASA and senior author of the study. "That can have serious consequences after the return to Earth, so we're looking into whether there are measures that can be taken to prevent or counteract that loss."
The results were presented at the American College of Cardiology's 63rd Annual Scientific Session.
The data also shows that the heart's change in shape is only temporary, and that the heart returns to normal shape just after the astronaut returns to Earth, AniNews reported.
It is a necessity for scientists to further understand the effects of long exposure to space on the heart in order for the mission to Mars in the 2030s to take place. For the study, NASA and Russia's space program look to keep two astronauts on the International Space Station for a whole year in 2015, International Business Times reported.
Thomas said scientists were able to use models to predict the changes to the heart they observed in the astronauts.
"It gives us confidence that we can move ahead and start using these models for more clinically important applications on Earth, such as to predict what happens to the heart under different stresses," he said.
