The ex-Tottenham Hotspur midfielder was given a quadruple bypass after the cardiac event.
Bypass helps to divert blood around narrowed or clogged parts of the major arteries, leading to improvement in blood flow and oxygen supply to the heart.
Glenn previously said about the time: “I was taken ill on my birthday, so Simon Daniels who saved my life really couldn’t give me a better present, could he?
“I can’t remember too much of the day before it all happened until I woke up in hospital.”
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