Chris Cairns in intensive care after heart surgery

Former New Zealand all-rounder Chris Cairns is in an intensive care unit at a Sydney hospital after undergoing cardiovascular surgery following a major heart incident in Canberra last week.

St Vincent's Hospital in Sydney said Cairns, who was admitted on Tuesday, is in "a serious but stable condition" in intensive care.

His wife Melanie Cairns said the cricketer had surgery in Canberra after a "major medical event" late last week but the seriousness of his condition required him to be transferred to St Vincent's for another operation.

"Chris' family and friends are heartened by the respectful and warm manner in which this terrible news has been reported, and received by the public, both in New Zealand and around the world, and thanks everyone for their warm wishes, prayers, and kind words," she said in a statement on Wednesday.

New Zealand media outlet Newshub on Tuesday reported 51-year-old Cairns had suffered an aortic dissection - a tear in the body's main artery.

"We're deeply concerned to hear of Chris Cairns' medical emergency," Cricket New Zealand boss David White said in a statement.

"Our thoughts are with his family in Aus and here in NZ. Chris is a much loved husband, father, and son - and remains one of our finest all-rounders. We hope he's able to make a full recovery."

Cairns played 62 Tests, 215 one-day internationals and two Twenty20 matches for New Zealand between 1989-2006.

His father Lance also represented New Zealand in cricket.

News of his health setback rocked New Zealand, where former team mates expressed sympathy for his family.

"It's absolutely devastating. It's the worst news you could possibly get," former New Zealand team mate Chris Harris told local media.

Cairns has lived in Canberra for several years.

After retiring from international cricket, he was the subject of allegations of match-fixing in India as captain of the Chandigarh Lions in the defunct Indian Cricket League (ICL) in 2008.

He denied any wrongdoing and fought several legal battles to clear his name, winning a libel case against former Indian Premier League chairman Lalit Modi in 2012.

In 2015, he was cleared of perjury in relation to the libel case after being charged by Britain's Crown Prosecution Service.

Former New Zealand captain Brendon McCullum, who testified against Cairns during the perjury trial, said the cricket community was suffering along with Cairns's family.

"It's a difficult subject to obviously talk about. We haven't seen each other for quite a long time,” McCullum, a host on New Zealand radio station SENZ, said.

"Our relationship is unimportant in the whole thing, the fact is that Chris is a father and also a son to Lance and (mother) Sue.

"Today my family and myself are thinking of those people who are suffering."