Scientists are developing a simple blood test to predict who is most at risk from the world’s most common inherited heart condition.
Millions of people worldwide have hypertrophic cardiomyopathy (HCM), a disease of the heart muscle where the wall of the heart becomes thickened. It is caused by a change in one or more genes and mostly passed on through families.
Some feel fine most of the time and have few or no symptoms. But others can suffer complications, such as heart failure and abnormal heart rhythms, which can lead to a cardiac arrest.
The problem is there is no cure. Doctors also do not know which patients with the genetic condition are most at risk from deadly complications.
But now a team of scientists from universities including Harvard and Oxford have found a way to forecast risk for people living with HCM.
The blood test could identify those patients most in danger of complications, enabling them to be monitored more closely or receive life-saving treatment.
In a landmark study, the team measured the levels of a protein, N-terminal Pro-B-type natriuretic peptide (NT-Pro-BNP), in the blood of 700 HCM patients.
NT-Pro-BNP is released by the heart as part of normal pumping. But high levels are a sign the heart is working too hard. Those with the highest levels had poorer blood flow, more scar tissue and changes in their heart which could lead to atrial fibrillation or heart failure.
A blood test measuring NT-Pro-BNP could transform the care of millions of people with the world’s most common inherited heart condition.
The study leader, Prof Carolyn Ho, the medical director of the cardiovascular genetics centre at Harvard medical school, said the test could help “target the right therapies to the right patients at the right time”.
She added: “Continued studies on blood biomarkers will lead to better understanding of HCM so that, in future, we can offer our patients a blood test to identify who is at high versus low risk of experiencing serious consequences of the disease.
“People with the highest risk could be targeted for potentially life-saving treatments as they stand to receive the greatest benefit, while those at lowest risk could avoid unnecessary treatment.”
Lara Johnson, 34, from Southampton in the UK, is one of many who could benefit.
Eight years ago, she began experiencing breathlessness and fatigue. After being referred by her GP for hospital tests, she was diagnosed with HCM. Several relatives on her father’s side were subsequently also diagnosed with the condition.
“One of the hardest parts of living with HCM is the constant uncertainty, never knowing what might change next,” Johnson said. “A simple blood test, which could help identify future risks earlier, would take away so much of that anxiety.”
She added: “It could give people like me a chance to prepare and adjust our lifestyles as needed, and help us to feel more in control. That kind of clarity wouldn’t only help me, it would make a world of difference for my whole family.”
Prof Bryan Williams, the chief scientific and medical officer of the British Heart Foundation, which funded the research, said the test “could benefit patients around the world”.
“After a diagnosis of HCM, patients and their families want to know what the future holds. This study shows that measuring various proteins circulating in the blood could help predict how the heart is functioning and future risk of complications from heart disease.
“This new method may also provide insights in the evolution of the structure and function of the heart in people with HCM that could point to new ways of treating this condition to reduce future risk.”
