The heart doesn’t have it easy in space.
Going to space certainly is cool. Unfortunately, space travel exposes astronauts to many factors (radiation and microgravity, for example) that impact cardiovascular health.
After long periods of weightlessness the heart can change shape and become up to 10% more spherical, making it less efficient to work. Blood pressure drops approximately 10mmHg (comparable to taking a blood pressure medication).
Microgravity affects blood distribution with more blood going to the chest and head. Approximately 1.9L of fluid can be displaced from lower to upper body. Whilst floating around the space station sounds like a lot of fun, the heart much prefers having our feet firmly on the ground.
Space and arrhythmias
Space environment can also contribute to the occurrence of arrhythmias – something that NASA is working to understand to better support astronauts on long-term flights (to Mars, for example). The challenge is not only to understand what causes or escalates the development of arrhythmias, but also of ways to treat and prevent them whilst in space.
Arrhythmias can lead to several very serious consequences including stroke, dementia and even sudden cardiac death. Scientists have been developing ways to monitor the heart and effectively detect any changes that will affect astronauts’ wellbeing.
Monitoring astronauts’ heart health
Monitoring devices used in space need to meet several criteria. For example, being minimally invasive and requiring low energy to function and to transfer data. The latter point is one of the trickiest since lowering computational complexity has an impact on accuracy, and no one is keen on compromising on that.
Devices that attach directly to astronaut’s skin, as well as smart garments where sensors are incorporated into the fabric have been used. Astronauts have worn special watches, headbands, Holter monitors, vests and many other devices to help scientists understand how space travel affects heart health and other aspects of wellbeing.
Returning to Earth
Understanding how to support astronauts in space helps us develop systems that can be used on Earth too. Return to Earth doesn’t mean that the heart simply bounces back and returns to normal. Time spent in low gravity weakens the heart muscle and disrupts heart rhythm. In addition, time spent in space creates changes similar to ageing – stiffening of the artery walls, for example.
Knowledge gained from working with astronauts can be applied to many social groups, including athletes, military, people exposed to adverse environmental condition or extreme altitudes, and elderly with varying heart rate just to name a few.
Whether you are exploring the stars or new paths in your local park, let’s stay heart happy!
References:
- British Heart Foundation, ‘What can heart researchers learn from astronauts in space’ – to access the article, click here.
- NASA, ‘Risk of cardiac rhythm problems during spaceflight’ – to access the article, click here.
- Today.com, Astronauts’ strange health problems after return – to access the article, click here.
- Pramanik J, Kumar A, Panchal L, Prajapati B. ‘Countermeasures for Maintaining Cardiovascular Health in Space Missions’ Curr Cardiol Rev. 2023; 19(5): 57-67. doi: 10.2174/1573403X19666230330083225. PMID: 37005513; PMCID: PMC10518885.
- Image credit: NASA via Unsplash.
