Dropping to the bathroom floor with crushing pains in her chest, Irene Birtwhistle was convinced she was having a heart attack.
‘I was in agony,’ recalls Irene, 53, who lives in Turriff, Aberdeenshire, with husband Simon, a retired council road worker and their children, Christopher, 18, and Sophie, 13.
‘The stabbing pains in my chest had woken me early at 6am, my skin was clammy and sweaty, and I was breathless and nauseous. I rushed to the bathroom and vomited, and then I shouted to Simon to call for an ambulance. I was terrified as my symptoms ticked all the boxes for a heart attack.’
The ambulance arrived within ten minutes, yet before the crew had time to take an ECG reading to check the activity and rhythm of her heart, Irene’s pains had mysteriously vanished.
‘It was like a switch had been flicked off,’ she recalls. ‘By the time we got to our local hospital, all my symptoms had died down and my ECG reading was completely normal.’
Irene, a retired water company sampler, was transferred to a larger hospital, where a nurse initially diagnosed indigestion.
Dropping to the bathroom floor with crushing pains in her chest, Irene Birtwhistle (pictured) was convinced she was having a heart attack
Yet further blood tests showed Irene had raised levels of a chemical called troponin — high levels indicate the heart has been damaged and can be a sign of a heart attack.
However, a consultant cardiologist ruled out a heart attack because an angiogram (X-ray of the blood vessels) performed six weeks earlier had revealed her blood vessels looked clear.
The consultant instead diagnosed a coronary artery spasm, which affects the muscles of the artery wall, temporarily reducing blood flow to the heart — this can happen spontaneously or be triggered by stress, exercise, cold weather or even the menstrual cycle.
So Irene was sent home the next day, and told to ‘forget about it’.
She was to suffer two further terrifying episodes — in October 2016 and October 2017 — again experiencing agonising chest pains, sweats and vomiting.
Ambulances were called and each time her symptoms vanished within around 15 minutes and her ECG readings were normal.
‘I felt they thought I was a hypochondriac or neurotic and was having a panic attack,’ she says.
Irene, a retired water company sampler, was transferred to a larger hospital, where a nurse initially diagnosed indigestion
On a third occasion a consultant again concluded her attacks were due to coronary artery spasms — and again reassured her they were nothing to worry about.
Sceptical, Irene began her own research online and came across support groups for those affected by spasms and a lesser-known type of heart attack called a MINOCA (myocardial infarction with non-obstructed arteries).
While a traditional heart attack is brought on by a blockage to an artery, a MINOCA is triggered by a temporary blockage — including as a result of coronary artery spasms — and so angiograms will show the blood vessels are clear.
MINOCA symptoms can be similar to a classic heart attack. ‘But they may also wax and wane over several days, because the artery is open and any blockage is only temporary,’ says Colin Berry, a professor of cardiology and imaging at Glasgow University.
According to research published in June, MINOCAs account for between 5 and 15 per cent of all heart attacks.
More common in women and those under 55, they can be hereditary and can occur for a number of reasons, including a build-up of fatty deposits rupturing and breaking away from the lining of the artery, causing a temporary blockage that clears as the plaque disperses. Other causes include coronary artery spasms.
Diagnosing a MINOCA is complex: it involves a blood test to measure troponin levels and an immediate follow-up with an angiogram, as well as functional tests and a cardiac MRI, which will show up any damage suffered by the heart.
Despite being a recognised medical event,
