Heart Rate Variability as a Predictor of Mortality in Heart Failure

Researchers examined whether heart rate variability, the small changes in time between heartbeats, was linked with survival in people with heart failure. They compared heart-rate measurements with whether participants later died. This type of research can show a warning sign or association, but it cannot prove that low variability causes death. The available study details do not report how many people took part or exactly how heart rate was measured.

What this means for you: This may help doctors estimate risk, but it does not show that changing heart rate variability prevents death. It is not a reason to buy a wearable, supplement, or treatment based on this study alone.