Good Evening. My Husband Died Of An Apparent Heart Attack

Good evening. My husband died of an apparent heart attack this past Spring. He died on an island in the Caribbean. The autopsy results have not yet been made available to me and I have been told it could take a year or more for them to reach me as they have to go through our Federal gov't as he was a non National on the island. He had been on the island for 5 days. He had been experiencing some rather significant stress at home before leaving for the Caribbean. This stress he had brought on himself, and it had escalated just days before departing. With the high level of stress, the change in elevation to sea level from @500ft above sea level, and the retention of fluid from consuming more "liquid" than normal, what other added triggers could have caused him to have the "heart attack" ? increase in humidity? unusual exercise? food? He was only 56 years old. weighed approx. 180 lbs and was 5'11" tall. His diet had not been good for some time. He ate foods that were high in sugar, salt and unhealthy fat. Not what I eat.( I eat mostly raw veggies, fruit and lots of dark green leafy veggies and vegetables high in proteins, which he wouldn't eat and he didn't like 'Raw". ) Was this a time bomb ready to explode given the circumstances? Thank you for your help. Anna