A simple test appears very good at ruling out heart attacks in people who go to emergency rooms with chest pain, researchers say.
A large study in Sweden has found the blood test plus the usual electrocardiogram of the heartbeat are 99 per cent accurate at showing which patients can safely be sent home rather than admitted for observation and more diagnostics.
Of nearly 9000 patients judged low risk by the blood test and with normal electrocardiograms, only 15 went on to suffer a heart attack in the next month, and not a single one died.
"We believe that with this strategy, 20 to 25 per cent of admissions to hospitals for chest pain may be avoided," says Dr Nadia Bandstein of the Karolinska University Hospital in Stockholm.
She helped lead the study, published in the Journal of the American College of Cardiology and presented on Sunday at the cardiology college's annual conference in Washington.
Chest pain sends more than 15 million people to emergency rooms in the United States and Europe each year, and it usually turns out to be due to anxiety, indigestion or other less-serious things than a heart attack. Yet about two per cent of patients having heart attacks are mistakenly sent home.
People may feel reassured by being admitted to a hospital so doctors can keep an eye on them, but that raises the risk of picking up an infection and having expensive care they'll have to pay a share of, plus unnecessary tests.
The study included nearly 15,000 people who went to the Karolinska University hospital with chest pains over two years.
About 8900 had low scores on a faster, more sensitive blood test for troponin, a substance that's a sign of heart damage.
The test has been available in Europe, Asia and Canada for about three years but it is not yet available in the United States.
The patients were 47 years old on average and 4 per cent had a previous heart attack. About 21 per cent of them wound up being admitted.