Cliff Grover was on holiday visiting family in New Zealand in December 2017, when he suddenly felt an incredible pain in his chest.
The grandfather, now 66, was rushed to hospital amid fears he could be in the midst of a fatal heart attack.
But doctors discovered he had in fact suffered from a potentially deadly aortic dissection, a condition that takes place when the inner layer of the aorta, the large blood vessel branching off the heart, tears.
Mr Grover, from Durris near Banchory, had to endure a 14-hour operation over Christmas to save his life.
He has now been appointed as the Scotland representative for the patient association Aortic Dissection Awareness UK and Ireland (ADAUI), and wants to help raise the profile of the illness.
He said: “I was visiting my daughter in New Zealand over the Christmas holidays, and just outside her house in the front garden I felt this absolutely colossal pain in my chest, and knew something was drastically wrong.
“I ran inside and managed to shout ‘chest pain’ before I passed out.
“I did in fact have a heart attack, but it was only a day or two later they found out that the heart attack was secondary to an aortic dissection.
“I had a 14-hour operation from the 24th, and woke up on Christmas morning with some new plumbing, which was quite the Christmas present for my family.”
Mr Grover added: “I want to use this experience to help give every person in Scotland the same chance that I was given and, where possible, prevent dissections from happening.
“Around 300 people a year will suffer a life-threatening aortic dissection, yet UK-wide a majority of the affected don’t survive as it is a rare condition and there are problems of delay, and sometimes misdiagnosis.”
Gareth Owens, the chairman of ADAUI, said: “We have appointed Cliff as our Scotland representative to ensure that no part of the UK misses out on the huge improvements in diagnosis and care for aortic dissection that are going to take place over the next few years as a result of our work.
“Our mission is to change the healthcare landscape for aortic dissection patients, to ensure that many more access the right care and survive with a good quality of life, as Cliff and I have done.
“We would like everyone in Scotland who is interested in the aorta to get to know him and to work with us on our Think Aorta campaign and other initiatives.”
To find out more, people can visit www.thinkaorta.org