The heart is the body's hardest-working muscle. Whether you're awake or asleep, or exercising or resting, your heart is always at work. It pumps blood through arteries to deliver oxygen to organs and ...

Millions of people live with atrial fibrillation, a racing, uneven heartbeat that can leave you exhausted and scared. Yet it ...

Over the course of just one month in space, engineered human heart tissue got weaker, its ‘beating’ patterns became irregular and it underwent molecular and genetic changes that mimicked the effect of ...