cardiophobia
/kɑrdiˌoʊˈfōbiə/Definitions
1. noun
a persistent and irrational fear of the heart or cardiovascular system
“Her cardiophobia prevented her from visiting the doctor for a routine checkup.”
2. noun
a fear of dying or a fear of death related to the heart or cardiovascular system
“He has a severe case of cardiophobia that affects his daily life.”