Having a heart attack in the middle of a presidential campaign at age 78 is really not good. I like Bernie, voted for him in 2016, would probably vote for him again. But... let's acknowledge what just happened here
I'd probably vote for him notwithstanding any health issues. But at least in terms of public perception, it's pretty bad. You can't blame voters for taking this into account. Media coverage of him is often skewed/unfair, but the campaign itself just confirmed the heart attack
This is from a statement put out by the campaign. A "myocardial infarction" is a heart attack 
