reductions in heart rate variability are a predictor of sudden cardiac death, even in individuals without a prior history of cardiovascular disease

Research indicates that a highly variable heart rate increases your capacity to respond and adapt to life’s challenges.
In a sense, it makes your cardiovascular system more flexible. If you’re less able to switch to the rest system, you’re more likely to feel stressed because your body is indicating that there’s danger in the environment – even if there isn’t.
Research has shown that reductions in heart rate variability are a predictor of sudden cardiac death, even in individuals without a prior history of cardiovascular disease.

1. Daniel Quintana

   PhD candidate and researcher at University of Sydney
   

2. Andrew Kemp

   NHMRC Career Development Fellow at University of Sydney
   

http://theconversation.edu.au/depression-can-break-your-heart-literally-1102