Cyrus was under tremendous stress, you could tell it in his voice and response to questions. Not sure how old he is but those in their 50’s have a great chance of cardiovascular issues, more than those in their 60’s or above. Collateral circulation that develops has proven to reduce cardiac issues later in life but of course other circumstances may cause a cardiac episode after age 60 but in my experience chances go down the longer you survive.
Hope he has a speedy recovery and is back leading the charge soon.