‘Stress’ is a complex subject to define. I would like to define stress as ‘an environmental challenge to which an organism reacts’. In the subject of biology, we often talk about heat stress, cold stress and chemical stressors of various kinds. I think it is a mistake when we think of stress on a personal level and ignore the sheer biology involved in stress responses.
The complexity of the neuro-psycho-endo-and immunological responses to stress makes it very challenging to give a clear response to the above-stated question. It’s like asking ‘what does long-term sun exposure does to the skin?’ – The answers would fill many encyclopedic volumes and still be incomplete. However, there are several types of heart diseases that are proven to have connections to stress.
It is well demonstrated that a combination of an activated sympathetic nervous system and consequent hormonal cascades result in ‘stunning’ of the heart muscles. Stunning is a form of acute cardiac failure. The myocardium is not damaged per se but the compromise of cardiorespiratory function can still have fatal consequences. Hence, many researchers have projected this condition as proof that it is possible to ‘die from a broken heart’ in both a literal and figurative sense simultaneously.