A new scanning method can detect deadly heart conditions before symptoms appear

The research funded by the British Heart Foundation and published in the journal Circulationopens up the prospect of treating the condition in its earliest stages.

Being able to detect HCM earlier than before would also help trials investigating gene therapies and drug treatments aimed at halting disease progression in those at risk.

HCM is an inherited condition that affects around 1 in 500 people in the UK. This causes the walls of the heart muscle to become thicker than normal, affecting how well the heart can pump blood around the body. It is the leading cause of heart failure and sudden cardiac death.

Researchers from UCL, Barts Heart Center and the University of Leeds studied the hearts of three groups: healthy people, people who already had HCM, and people with the genetic mutation that causes HCM but no obvious signs of disease (no thickening of the heart muscle).

To do this, they used two cutting-edge cardiac scanning techniques: cardiac diffusion tensor imaging (cDTI), a type of MRI scan that shows how heart muscle cells are arranged and packed together (heart microstructure), and cardiac perfusion MRI (CMR), which detects problems with the small blood vessels that supply the heart muscle (microvascular disease).

The scans showed that people with clear signs of HCM had very abnormal heart muscle cell organization, and high and severe rates of microvascular disease compared to healthy volunteers.

Most importantly, the scan is also able to identify abnormal microstructure (disorganization of muscle cells) and microvascular disease in people who have the problematic gene but no symptoms or muscle thickening. They found that 28% had defects in their blood supply, compared to healthy volunteers. This means that doctors can more accurately find the early signs of HCM developing in a patient’s heart.

The first drug to slow the progression of HCM – mavacamten – has recently been approved for use in Europe and will allow doctors to reduce the severity of the disease once symptoms and muscle thickening appear. Genetic therapies are also under development that can prevent symptoms completely by intercepting the development of HCM in its early stages.

CMR perfusion is already used in some clinics to help differentiate people with HCM from other causes of muscle thickening. Researchers think this revolutionary new therapy, combined with cDTI and perfusion CMR scans, gives doctors the best chance of treating people at risk for HCM early enough that the condition never progresses.

Dr George Joy, who led the study with Professor James Moon and Dr Luis Lopes (all UCL Institute of Cardiovascular Science), said: “The ability to detect early signs of HCM could be very important in trials testing treatments aimed at preventing early disease development or correcting genetic mutations. Scanning may also allow treatment to start earlier than we previously thought.

“We now wanted to see if we could use the scan to identify which patients with no symptoms or thickening of the heart muscle are most at risk for severe HCM and its life-changing complications. Therefore, the information provided from scans can help doctors make better decisions about how best to treat each patient.”

Dr Luis Lopes (UCL Institute of Cardiovascular Science), senior author of the study, said: “By correlating advanced imaging of our cohort of HCM patients (and relatives) with extensive genetic testing, this study detected microstructural abnormalities. life in mutation carriers for the first time and was the first to compare these parameters in HCM patients with and without causal mutations.

“These findings allow us to understand more about the early subclinical manifestations of this serious condition, but also provide additional clinical tools for screening, monitoring, and hopefully in the near future for therapeutic decision making.”