I have never seen this. If the heart improves, it is hard to know when it will. What we would do is treat them with a good medical regiment and follow them closely to see if it does improve. There is a chance that once the damage is done the heart may not improve. The role of stress in heart failure is not well established.
Stress is usually a risk factor for unhealthy lifestyles, which can lead to heart attacks.
By this, I mean people abuse substances, smoke tobacco, eat unhealthy foods which are risk factors for heart attacks and contribute to heart failure. Heart failure is not necessarily a death sentence. There have been many breakthroughs in the last 10 years with medical management. Generally, if treated by a heart failure specialist, the survival is quite good for people with minimal symptoms. I heard that if there were a lot of adrenalin in your system you would be more prone to heart failure.