An international team of researchers based at King’s College London is developing a blood test to diagnose heart attacks which could one day be carried out on a simple handheld device, enabling rapid diagnosis in A&E departments by negating the need for lab tests.
The research regarding the blood test was part-funded by the British Heart Foundation and presented at the British Cardiovascular Society Conference in Manchester. It uses similar technology to the troponin test, but analyses the level of a protein called cardiac myosin-binding protein C (cMyC). The amount of cMyC in a patient’s blood stream increases rapidly after a heart attack. The fact that CMyC increases to a higher extent than troponin protein means that the test can rule out heart attacks in a higher proportion of patients straight away.
Part of the international research team took blood samples from 776 patients traveling to hospital by ambulance in Denmark. The researchers at King’s College London then tested the samples for cMyC.
In patients who did have heart attacks, cMyC was present in high enough concentrations 95% of the time for an on-the-spot diagnosis. The cMyC test outperformed the currently-used troponin test, which was only capable of diagnosing around 40% of patients in this way. This was largely because troponin takes longer to reach detectable levels in the blood after a patient suffers a heart attack.
The researchers are now hoping to create a portable testing device to be used in UK A&E departments, and in ambulances in countries where there are often considerable distances to be travelled when taking patients to their nearest hospital. A handheld device could replace the time-consuming processes involved in having blood samples analysed in hospital labs.
It has been estimated that over two thirds of patients who attend A&E with chest pain symptoms have not had a heart attack. However, all will receive an ECG and a blood test to measure troponin levels.
The rapid results of the cMyC blood test could reassure worried patients in A&E departments, free up bed space and save hundreds of thousands of pounds per hospital every year.
One of the lead researchers at St Thomas’ Hospital, London, Dr Tom Kaier said: “It is important for both patients and doctors to work out early who has had a heart attack and who hasn’t.
“Now that we know that this test is sensitive enough to give an almost immediate heart attack diagnosis, we need to work on developing a testing device. We’d love to see this used in A&E departments within the next five years.”
British Heart Foundation associate medical director Professor Jeremy Pearson said: “Big heart attacks are often easy to diagnose with an ECG but smaller heart attacks, which are more common and also life-threatening, are more challenging. The troponin test has been used for around 20 years and is currently the most powerful tool we have for diagnosing such heart attacks, but there is always room for improvement.
“These initial results with the cMyC test look very promising for patients, who could be more quickly diagnosed and treated or reassured and sent home. However, further research is necessary before it can be recommended as a replacement for the troponin test.”