The 37-year-old Spaniard spent eight years at the north London club but was forced to hang up his gloves after he was diagnosed with the problem during a medical with Serie A side Cagliari.
I gave him [more credit than others] because I played him
And Wenger was quick to praise the shot-stopper, who made 175 appearances for the Gunners between 2004 and 2012.
“It’s very sad that he has a heart condition,” said Wenger.
“I think he is at an age where you can accept that he retires from competitive professional football but I hope there’s nothing bad for his future and his health.
“I gave him [more credit than others] because I played him. I think he was a great goalkeeper.”
Almunia spent two seasons at Watford after leaving Arsenal, where he racked up 81 appearances.
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