Heart in trouble after lung treated — not appreciative (10)

I believe the answer is:

ungrateful

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'not appreciative' is the definition.
I can't tell whether this defines the answer.

'heart in trouble after lung treated' is the wordplay.
'heart in' means to look at the middle letters.
'treated' is an anagram indicator.
The middle of 'trouble' is 'u'.
'after'+'lung'='afterlung'
'afterlung' with letters rearranged gives 'ngrateful'.
'u'+'ngrateful'='UNGRATEFUL'

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(Other definitions for ungrateful that I've seen before include "Disagreeable" , "Thankless" , "no thanks" .)

I've seen this clue in The Times.

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