Lord Alan Sugar's wife thought he was being a "hypochondriac" before he was told he needed emergency heart surgery.
The 'Apprentice' star - who underwent an operation 18 months ago to have a stent inserted after one of his arteries narrowed - had been suffering from chest pains so sought medical help for reassurance, and he and his spouse Ann were stunned by what he was told.
Speaking during his upcoming appearance on 'Piers Morgan's Life Stories', he said: "Ann went with me to this place where I had a scan.
"I have got a friend who owns a scanning clinic and she came with me and she said 'What are we doing wasting our bleeding time here? You are a bloody hypochondriac. There is nothing wrong with you. You have got a little tweak over there and a little pain. There is nothing wrong. We are standing here wasting blooming time.
"I said 'Don't worry. I just want to check it out.' 'The doctor who is reading the scans and the pair of us nearly passed out. Because he said to me, 'You better go straight to A&E'."
The 72-year-old businessman admitted the news came as a "great shock", particularly because he and Ann had been on a 25-mile tandem ride earlier in the day.
He said: "It was a bloody shock. It was a great shock. It really was a shock. I nearly passed out to be honest.
"You start going into cold sweats and the next thing you know you pass out. I nearly got to that stage. Ann was shocked by it all like I was. I understand why she felt I was being a bit of a hypochondriac.
"In fact that morning Ann and I went out on the tandem. We rode 25 miles on the tandem."
Elsewhere during the interview, Alan admitted he had a fake BAFTA made for himself and his on-screen assistant, Karren Brady, after executives kept the real gongs which they received when 'The Young Apprentice' won the 2012 award for Best Constructed Factual.
He said: "They gave the BAFTA to the accountant, I got very annoyed and I nicked it from her.
"On the bloody night of the BAFTA awards it wins. My idea, my concept.
"So the producer gets one, the guy who does all the photography and some accountant. I am like 'What is going on here. What have you done?'
"I put it into a mould and I sent the mould out to China and they made about six. I gave one to Karren."
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