A team of UK researchers have found that the presence of T-cells expressing a molecule called cMet in the blood strongly indicates that a person has myocarditis, paving the way for the condition to be detected through a routine blood test.
Currently, the gold standard in the diagnosis of myocarditis is a heart biopsy, an expensive and invasive procedure which can sometimes still miss signs of the condition.
The researchers, funded by the British Heart Foundation (BHF), hope that their findings will improve the diagnosis of myocarditis and help patients get access to treatment earlier, thereby reducing the risk of developing life-threatening complications such as abnormal heart rhythms or heart failure.
“This blood test could revolutionise the way we diagnose myocarditis, allowing doctors to step in at a much earlier stage to offer treatment and support,” said Professor Sir Nilesh Samani, medical director, BHF.
The study, published in the journal Circulation, involved the comparison of blood samples from several groups of patients, 34 of which received a final diagnosis of myocarditis.
Patients with myocarditis were found to have significantly increased levels of T-cells with cMet on their surface compared to other groups, including heart attack patients, and those with no medical conditions.
The researchers also found that cMet-expressing T-cells become activated by molecules expressed by heart cells, producing an immune reaction against these cells that leads to inflammation of the heart muscle. This adds to the growing body of evidence that myocarditis is an autoimmune condition.
Myocarditis is inflammation of the heart muscle, which can reduce the heart’s ability to pump blood. The condition can cause chest pain, shortness of breath and rapid or irregular heart rhythms.
Because these symptoms can be easily mistaken for other conditions, myocarditis is difficult to diagnose, with Myocarditis UK estimating that one young person dies every week in the UK due to previously undiagnosed myocarditis.
Professor Federica Marelli-Berg, study lead at Queen Mary University of London said: “Early intervention is crucial when treating myocarditis as, in some cases, it can be only a matter of weeks between the onset of symptoms and development of heart failure. But without a diagnosis doctors can’t offer their patients the right treatment.
“We think that this test for myocarditis could be a simple addition to the routine blood tests ordered in doctors’ surgeries. When viewed in combination with symptoms, the results could allow GPs to easily determine whether their patients have myocarditis.”