An adventurer is preparing for one of the world’s most dangerous rows in the Antarctic in honour of the “forgotten hero” of Ernest Shackleton’s Endurance voyage – just months after undergoing open heart surgery.

Jamie Douglas-Hamilton is also hoping to raise more than £100,000 for the British Heart Foundation (BHF) when he and five others undertake the 950-mile journey from Elephant Island to South Georgia on January 10.

Mr Douglas-Hamilton is calling for the Polar Medal to be awarded posthumously to Harry McNish, the ship’s carpenter on Shackleton’s ill-fated voyage which ended with the expedition vessel Endurance being sunk by pack ice in October 1915.

The group managed to reach Elephant Island and McNish adapted the James Caird lifeboat to make it seaworthy for the voyage which some of the crew made from there to South Georgia to seek help.

The Harry McNish Row will follow the route sailed by the James Caird, in what is considered one of the world’s most treacherous seas where waves can reach 80ft in stormy conditions.

It was originally planned for December 2021 but had to be postponed which turned out to be fortunate as, unknown to him, Mr Douglas-Hamilton had a heart condition that he believes would have killed him on the journey.

He told the PA news agency: “If I had gone on this expedition as planned last year I would have definitely died.

“I was born with a bicuspid aortic valve where you’ve only got two valves going to the aorta not three. It had been leaking for 20 years but got worse last year and after having Covid I had to go to get it checked out.

“I was told I needed immediate open heart surgery. I couldn’t believe it, I went in there trying to get antibiotics and then had to go through this process, my heart was double the size.”

Mr Douglas-Hamilton is the only British member of a team of six who will row three at a time in 90-minute shifts around the clock over the course of the journey, which is expected to take two and a half to three weeks.

He said it has been a struggle to get his fitness back up to the same level after surgery in August this year but he is now feeling excited about the challenge ahead.

The team, captained by Fiann Paul, from Iceland, will make the journey unassisted and without wind power and hope to set a record for being the first to row the Scotia Sea by human power alone.

Harry McNish, from Port Glasgow in Inverclyde, was one of the only members of the Endurance crew not awarded the Polar Medal due to his differences with Shackleton.

Mr Douglas-Hamilton, from Edinburgh, hopes his expedition will raise awareness about the heroic actions of the carpenter, who was nicknamed Chippy.

He said: “Harry McNish was the real hero of the Endurance expedition, he was portrayed as a mutineer, he wasn’t given a Polar medal and it’s a great injustice.

“He was the one who managed to save them all, who built the boat that got them from Elephant island to South Georgia, he built the crampons to get them over the ice, the mountains to the whaling station, at every stage he was behind them getting through.”

Mr Douglas-Hamilton added: “He was the real hero of the story, a forgotten hero of the Shackleton mission, who died destitute.”

John McNish, Harry McNish’s great nephew, said, “Our family are incredibly touched that Jamie is rowing the treacherous seas of the Antarctic which my great uncle sailed in the early 1900s and that the journey will be made in honour of him.

“Our family is incredibly proud of my great uncle, and we have always believed it to be very unjust that Chippy wasn’t given the Polar Medal.

“It is very exciting that this expedition, The Harry McNish Row, will highlight just how brave and courageous my great uncle was.”

Mr Douglas-Hamilton, who founded ACTIPH Water in 2017, is no stranger to adventure and has broken seven Guinness World records.

In 2014, he was part of a team which rowed 5,000 miles across the Indian Ocean, all the way from Australia to Africa.

And in their last expedition in 2019, he and his team rowed 750 miles from Cape Horn in South America to mainland Antarctica across Drake Passage.

Anyone who wishes to donate can do so at https://www.justgiving.com/page/jamie-row-challenge and they can donate £10 to British Heart Foundation by texting SCOTIA to 70607.