heart attack 
noun
1A sudden occurrence of coronary thrombosis, typically resulting in the death of part of a heart muscle and sometimes fatal: he died of a heart attack...
- This helps to slow the progression of coronary heart disease and makes a heart attack less likely.
- Being sedentary increases the risk of a heart attack or stroke by the same amount as smoking.
- While at home he became ill and eventually died alone after a heart attack.
1.1 humorous Used in reference to a reaction of shock or great surprise: OMG, I had a heart attack when he said White Sox! you nearly gave me a heart attack - I didn’t see you there!...
- He appeared out of nowhere, almost giving me a heart attack.
- I guess I couldn't stay mad at her, despite the fact that she almost gave me a heart attack.
- She had nearly been caught snooping in her parents' room and their sudden return had almost given her a heart attack.
Phrases
heart attack on a plate