The silent heart-attack epidemic: HALF of us don't realise we've had one

Nearly half of all heart attacks may be 'silent' but just as deadly, new research has warned.  

These heart attacks, which many people don't realise they are having, are particularly dangerous for women - yet repeatedly confused with indigestion, a pulled muscle or the flu.

Researchers have found that silent heart attacks are almost as common as the standard attacks that prompt hundreds of thousands of hospital admissions a year.

The team, from North Carolina, also discovered women who suffer a silent attack are more 50 per cent more likely to die within a decade, while in men the risk increases by a quarter.

They occur when the blood flow to the heart is temporarily blocked – as with a normal attack – causing potentially fatal damage and scarring.

But many patients either have no symptoms at all or wrongly assume they have indigestion, the flu or have strained a muscle.

Most never go to hospital or see their GP so are not offered vital medication or surgery which can prevent a fatal attack later.

The researchers and other experts say the public must be made more aware of silent heart attacks over concerns many are going unnoticed.

Heart disease is by far the biggest killer worldwide - and experts believe many of these deaths occur in patients who have previously suffered a heart attack without realising it.

Dr Zhu-Ming Zhang and other researchers from the Wake Forest School of Medicine in Winston-Salem, North Carolina, looked at the records of 9,498 middle aged men and women.

Over a ten year period some 7.4 per cent suffered a heart attack, and in 45 per cent of cases they were silent heart attacks.

The researchers were able to identify these attacks despite the lack of symptoms by looking at damage caused to the heart in scans.

They also found that women who suffered a silent heart attack were 58 per cent more likely to die within a decade and men 23 per cent.

Dr Zhang said her study had shown that silent heart attacks, or silent myocardial infarctions (SMIs), ‘were as common’ as ordinary heart attacks.

She added: ‘Given that SMI is characterised by no or mild symptoms, those patients are deprived from medical treatments that could prevent subsequent adverse outcomes, including a second MI or even death.’

Professor Jeremy Pearson, Associate Medical Director at the British Heart Foundation, said: ‘This study emphasises that individuals who have ECG (scan) results which suggest a heart attack, but who don’t have any classical symptoms, should be investigated more fully to determine their need for future treatment.

‘Since the patients in this research were studied, heart attack diagnosis has improved significantly with more people being correctly diagnosed as suffering from a heart attack than ever before. 

'The number of people being screened for risk and treated to prevent future cardiac events has also increased substantially since the 1990s.

Dr McClintock said: ‘The key point is that we have to stop thinking about health in the last third of life in terms of “diseases” and start thinking in terms of a mosaic of strength and weaknesses, with the most important aspects of that being non-disease characteristics such as past injuries and psychological well-being, mobility, living circumstances and social interactions.’ 

The research was published in the American Heart Association's journal Circulation.

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