<s>[INST] my 55 year old brother just died of a heart attack. i was with him as well as many other family members we were all outside and noticed he wasnt there we went in the house and found him sitting on the sofa his head was back eyes were closed mouth agape  he was a very funny color and was making snoring kind of noises what i want to know is what kind of symptoms could he have had so suddenly that he walked allthe way inside and sat down and died this all happened within 10 minutes was he in alot of pain. [/INST] Hello, Thanks for writing to Chat Doctor, I am Chat Doctor. First I would like to pay my commiserations on your loss, indeed that would have been a matter of great concern for you people. Here I would explain symptoms of massive heart attack to you.1) Central Chest pain compressional in nature.2) Gets worsened on exertion.3) May get referred to left arm shoulder or jaw.4) May accompany by palpitations.5) There may be black out if BP  </s>