The condition, acute pulmonary oedema, was caused by "a heart rhythm disorder", post-mortem tests revealed.
Foley, 42, died on Saturday night at the hotel in Paris where Munster were staying before Sunday's scheduled game against Racing 92.
His funeral will be held in Killaloe, County Clare, on Friday at 12:00 BST.
Foley's body will be flown to Shannon Airport on Wednesday before being taken to the family home.
Funeral mass will take place at St Flannan's Church, with burial afterwards at Relig Nua Cemetery.
The death of the former Ireland forward could "be linked to a cardiac problem", a spokeswoman for the Nanterre public prosecutor said on Tuesday.
Other toxicological analysis is under way, with results due in the coming weeks.
Pulmonary oedema means excess fluid collects in numerous air sacks in the lungs, making it difficult to breathe.
Foley's body was found in his room at 12:40 on Sunday by a member of hotel staff and a Munster player.
The European Champions Cup game was postponed.
Foley won 62 Ireland caps and made 201 appearances in the back row for Munster, leading them to their first European Cup triumph in 2006.
Munster head coach Anthony Foley died after a heart condition caused fluid to build up in his lungs, a French coroner has said.