Stop after eccentric CIA operation for medical emergency (7,6)
I believe the answer is:
cardiac arrest
'medical emergency' is the definition.
(a cardiac arrest is a medical emergency)
'stop after eccentric cia operation' is the wordplay.
I cannot really see how this works, but
'stop' could be 'arrest' (arrest is a kind of stop) and 'arrest' is located in the answer.
'eccentric' could be 'card' (card can mean an eccentric person) and 'card' is located in the answer.
an anagram of 'cia' is 'iac' which is present in the answer.
This accounts for all the letters.
This may be the basis of the clue (or it may be nonsense).
'for' is the link.
Can you help me to learn more?
(Another definition for cardiac arrest that I've seen is " Stoppage of the heart".)