But because the pain had subsided by the next day, the Macquarie Hills resident didn't think much of it, feeling well enough to play nine holes of golf.

She was running a tennis coaching session when the pain returned. Only this time, she felt a strange sensation in her arm too.

"Once I sat down the pain was excruciating," she said. "I had the chest pain, and down my arm. I was struggling to breathe. I felt nauseous. I thought I was going to vomit."

Mrs Musgrave-Edwards was having a "spontaneous coronary artery dissection" - a SCAD heart attack - responsible for around a quarter of heart attacks in women under 50.

Typically heart attacks are caused by build up of fatty acid plaque that blocks a coronary artery. But with SCAD, it is a "bleed" in the wall of the artery - caused by a tear or the rupture of a blood vessel - that blocks the blood supply.

"It was completely unexpected," she said.

"It was just freakish."

Further testing found she had "widespread" FMD - or fibromuscular dysplasia - which puts her at higher risk of stroke. Doctors found a "huge" aneurysm on one of her kidney arteries, which could have ruptured at any time.

"It possibly could have killed me as much as the heart attack," she said.

In August 2021, Mrs Musgrave-Edwards endured a 10-hour operation to remove the aneurysm, repair the artery, and transplant the affected kidney back into her abdomen.

"Having been a professional tennis player and being super fit and healthy, I'm trying to raise as much awareness of this as I can - just to let people know that any kind of chest pain, especially in women, shouldn't be taken lightly," she said. "It could be happening to you. I still wonder if I could have stopped it from progressing if I'd gotten it looked at the first day I felt that pain."

Mrs Musgrave-Edwards is one of a growing number of Hunter women to have a SCAD heart attack, with the rising incidence prompting Professor Bob Graham - from the Victor Chang Research Institute - to establish a SCAD clinic at John Hunter Hospital once a month.

He said 90 to 95 per cent of SCAD cases were women.

"There is almost definitely a hormonal element to it... and almost definitely a genetic component to it," he said. "Unfortunately, we don't know who's going to get it and who's not going to get it. That's the trouble. And also, it can recur in up to 30 per cent of cases. So a lot of these women live on tenterhooks wondering whether they're going to get another attack."

Professor Graham said it wasn't necessarily that the Hunter was over-represented with SCAD cases - but more likely that the region was lucky enough to have skilled interventional cardiologists adept at diagnosing it. The clinic at John Hunter Hospital made treatment and accessing specific information on SCAD easier for people who were previously travelling to Sydney for the same support.

He urged people experiencing persistent chest pain for more than five minutes to "get in and be seen".