Essendon premiership hero Wallis was rushed to hospital in Echuca on Sunday and underwent emergency surgery.
APOLOGETIC': AFL boss warns players over dire umpiring issue
The 52-year-old had life-saving surgery in Bendigo after being transferred from Echuca where he was working.
Wallis is reportedly recovering well in hospital and has reached out to concerned former teammates.
Wallis played in Essendon's premierships teams in 1993 and 2000 and served as the club's assistant coach under Grant Thomas in 2002 and 2003.
He played 127 games for the Bombers, kicking 42 goals and becoming known as one of the AFL's toughest players.
He recently attended Essendon’s Hall of Fame function where he celebrated the elevation to Legend status of Neale Daniher, Dr Bruce Reid, Dustin Fletcher and Gavin Wanganeen.
The major health scare comes just days after the deaths of cricket legend Warne and Victorian Labor senator Kitching.
Warne died on Koh Samui island in Thailand after friends found him unresponsive in his room.
Thai police later confirmed that Warne died of natural causes after an autopsy was performed on the Aussie legend's body.
Former Labor leader Bill Shorten said Senator Kitching suffered from "a heart problem" on Thursday evening in Melbourne and died soon after.
In a harrowing twist, Wallis is the same age as Warne and Kitching.
A tearful Mr Shorten told ABC Radio that Senator Kitching's death came as a shock and said she had been under great stress.
"Pre-selection is never easy. I'm not a coroner, I can't tell you why this woman at 52 was taken from us, but I have no doubt that the stress of politics and the machinations in the back rooms had its toll," he said.
"There were machinations and arguments going on, now that does happen, that's not unique.
"But we have a woman who's 52, who's pulled over by the side of the road and died unexpectedly. That's shocking. It's terrible."
Paul Couch died of a heart attack aged 51.
Darren Lehmann almost died of a heart attack aged 50.
Greg Page from the Wiggles aged 48.
Duncan Armstrong aged 52.
Kerry Packer aged 52.
Dean Wallis aged 52.
Shane Warne aged 52
Kimberley Kitching aged 52
weren't so lucky.
— Kevin Pollard (@football_roos) March 13, 2022
— 🔴⚫️Andy Bombers 🔴⚫️ (@andy_bombers) March 13, 2022
Cricketer Shane Warne 52, gone.
Senator Kimberly Kitching 52, gone.
Former Essendon AFL player Dean Wallis 52, survived, life saving surgery in Bendigo Hospital after collapsing in Echuca, Sat arvo.
Massive heart attacks in early 50’s.
Check your heart health folks. https://t.co/zALVdbLtP9
— 💧Chris Mac (@ChrisMac1270) March 13, 2022
Sending thoughts to Dean during this difficult time. Hoping for positive outcome. You're a Champion Dean- We're all with you.
— AlexS#DonTheSash (@alexmatthewsar) March 13, 2022
Shane Warne's death sparks warning for Aussies
According to a Heart Foundation survey, less than half of men are aware of risk factors for heart disease.
Only six per cent of men know that high cholesterol is a risk factor, and only four per cent know that high blood pressure can also increase risk.
"This is concerning because there are usually no signs or symptoms for high blood pressure or high cholesterol, yet they increase your risk of heart attack and stroke," Chief medical adviser Professor Garry Jennings told Yahoo News Australia.
It is recommended that all men 45 years and older should have regular heart checks.
"It’s common to hear men say that a heart attack or stroke was the first sign that something was wrong," Professor Jennings said.
"Having a Heart Health Check gives you the best chance of reducing your risk of a heart attack or stroke."
Warne's body arrived home in Melbourne on a flight from Thailand on Thursday night.
Warne's father Keith and mother Brigitte, holding a single flower, were among several family members to meet the flight.
The Dassault Falcon 7X jet left Thailand's capital Bangkok at 8.25am local time and arrived at Melbourne's Essendon Fields Airport around 8.35pm on Thursday.
Warne's eldest daughter Brooke and son Jackson were at the hangar, as was his ex-wife Simone Callahan.
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