Unless you were there for the autopsy...you really don't know what caused those cardiac events other than a clogged artery ( -ies).
3 guys is not an epidemic...nor cause for alarm. If they or anybody is really stressed from this job...they really should look for something else...or get on a treadmill.
3 Guys in a couple of months is a cause for alarm. It is unsafe. As you increase in age so does your chance of a heart attack.
The stress I talk about is from working much harder and longer in recent years. It adds up on your body. This profession in particular with its odd hours and abnormal bio rhythms takes its toll on most. I guess what little time we have with our family's we should be spending on a tread mill.