"Dilation of heart chambers!", doctor said to the French (8)

I believe the answer is:

diastole

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'dilation of heart chambers' is the definition.
'diastole' can be an answer for 'dilation' (thesaurus). I'm unsure of the 'of heart chambers' bit.

'doctor said to the french' is the wordplay.
'doctor' is an anagram indicator.
'the french' becomes 'le' ('the' in French).
'said' anagrammed gives 'dias'.
'dias'+'to'+'le'='DIASTOLE'

Can you help me to learn more?

(Another definition for diastole that I've seen is " bit of a heart-throb".)

I've seen this clue in the Sydney Morning Herald.

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