The 35-year-old is understood to be in a stable condition.
La Rochelle prop Uini Atonio has been forced to retire from rugby immediately after being hospitalised with a serious heart problem.
The 35-year-old, who plays for France at international level, is understood to be in a stable condition.
However, in a statement, La Rochelle said he remains in intensive care and will require a lengthy period of rehabilitation.
Atonio won two Champions Cup titles with the French club under head coach Ronan O'Gara.

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