Joanne woke up with 'crushing pain'. She had no idea she was having a heart attack.

Joanne Ludlow was just 36 when she suffered a heart attack that went untreated for days after she, her family and a GP all failed to recognise the symptoms.

While she had type-1 diabetes, it had not been linked to a higher incidence of heart disease 14 years prior.

Ms Ludlow had woken up with nausea and a pain across her upper back on Mother’s Day 2003, but put it down to the fact she had been exerting herself at work the previous day. She felt unwell the entire day and the next morning.

“I woke up around 5.30 and felt more nauseous but had a shower. That is when the pain started getting really bad. I had the most horrendous pain in my chest,” she said.

She said it felt like “boulders were crashing into her ribs from the inside, from every direction”. Her sister, who she lived with, arranged for her parents to take her to a medical centre, but still no one suspected a heart attack.

By this time, Ms Ludlow also had a strange sensation down her left arm, but when she saw the doctor he said it was inflammation of the heart, prescribed painkillers and told her to go home and rest.

Two days later, she suffered the crushing pain again, tightness in her chest and pain down her left arm. This time she went to her regular GP, who suggested an ECG, which she had the same day.

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“She said ‘get to hospital straight away’. I had three blocked arteries and had open-heart surgery about three days later,” she said.

It took a year for Ms Ludlow to recover from the surgery. She was left with ongoing complications, including damage to the heart, which could have been avoided had she gone straight to hospital.

“I would not have had the major heart attack if I had gone to hospital then,” she said.

She had also ignored earlier warning signs of tiredness, nausea, pain in her back and a strange feeling in her left arm.

“I used to go on big walks on the weekend and I would get this strange sensation in my left hand.”

More than 20 women die each day from heart disease

Heart disease is the biggest killer of Australian women, accounting for almost three times more deaths each year than breast cancer.

About 3000 women died from breast cancer in 2015 compared with 8700 heart disease deaths among women the same year.

It's these worrying statistics that are driving the Make the Invisible Visible campaign by the Heart Foundation to increase awareness of heart disease among women.

While heart disease deaths are more common among older women, the Heart Foundation wants women in the 25-to-45-year age bracket to know that heart disease can affect them too, especially if they carry one or more of the known risk factors; high cholesterol; high blood pressure, being overweight or obese; physical inactivity, smoking, diabetes or depression.

Women are sometimes diagnosed with heart issues during pregnancy, because the 30 to 50 per cent of extra blood volume in a pregnant woman’s body can alert doctors to a problem.

Former television reporter Kelly Landry was heavily pregnant with her first child when she was hospitalised with the early stages of heart failure as a result of a then undiagnosed heart condition.

She narrowly avoided surgery and defibrillation but was told days after her first child was born that she had a serious congenital heart defect. Her second pregnancy saw her hospitalised much sooner due to the damage caused to her heart from her previous pregnancy.

Ms Landry spent four months in hospital and told Channel 10 recently that since 2011, she had been hospitalised 20 times due to her heart condition. She said there were times “I was definitely afraid to fall asleep at night”.

“The problem with the condition I have is [that] it is kind of like the great unknown and they don’t really know how to treat it,” she said.

As an ambassador for the Heart Foundation, Ms Landry wants women to see their GP for a heart check and get a second or third opinion, including a heart ultrasound, if they think something is wrong.

The vague symptoms women experience compared with men is one of the reasons 24 women die each day from heart disease.

While men are more likely to suffer sharp chest pain and clutch their chest in what cardiologists call a “Hollywood heart attack”, women are more likely to suffer less obvious warning signs.

The lack of more obvious symptoms is one of the reasons why 60 per cent of heart failures affect women, according to the Heart Foundation’s Julia Power.

“Men have more heart attacks but women are more likely to die [from theirs],’’ she said.

“Forty per cent of women do not suffer from chest pain at all. Women’s symptoms are often generally feeling unwell, sweating and nausea.”

And because heart disease in women is detected later, she said “the damage is often greater’’, requiring more treatment.

'GPs are not thinking heart first' when it comes to women

The Make the Invisible Visible campaign also aims to raise awareness amongst medical practitioners, who are less likely to refer women for heart tests.

Misdiagnosis of women’s heart disease is common, with reflux and anxiety often diagnosed in place of something more serious.

“GPs are not thinking heart first,” she said.

“Often, if [women] are busy they are told it is stress-related or they are highly strung or they are menopausal, when really something more significant is going on.”

Heart Foundation National CEO Adjunct Professor John Kelly recently pointed to the significant “gender divide” when it came to heart disease among women. Figures show 50 Australian women will suffer a heart attack every day. Around half as many will die.

“Heart disease is the number one killer of Australian women, claiming 24 lives each day,” he said.

“A recent study by Sydney’s Georges Institute, which showed that women were less likely to be reviewed by their general practitioner for heart disease risk factors, offers another compelling case in point.

“The most recent available figures show that healthcare expenditure on men with heart disease doubled that of women.”

The Heart Foundation is urging women to learn the signs of a heart attack and how they differ between men and women; visit their GP for a heart health check and raise awareness among others by drawing a heart on their body, taking a photo and uploading the image to social media with the hashtag #womenshearts.

Know the warning signs

Women are more likely to experience non-chest pain symptoms of a heart attack than men, which may include:

• General discomfort in the neck, or a choking or burning feeling in your throat.
• A general ache, heaviness or pressure around one or both of your shoulders or a dull ache in the upper back.
• Pain, discomfort, heaviness or uselessness in one or both arms. This may also feel like numbness or tingling.
• Pain, heaviness, tightness, pressure or a crushing sensation in the centre of your chest. This discomfort may be mild and make you feel generally unwell.

Other symptoms include nausea or generally feeling of being unwell; feeling dizzy or light-headed; breaking out in a cold sweat; shortness of breath; difficulty breathing or taking a deep breath due to a tight or constricted feeling in your chest.

If any of these symptoms occur, stop what you are doing and tell someone. If they don’t improve within 10 minutes or if they get worse, call Triple-0.

The Make the Invisible Visible campaign runs nationally throughout June and aims to put women’s hearts at the forefront of their minds and educate them about the signs of heart disease.