Researchers have developed a new technology based on analysis of computed tomography (CT) coronary angiograms that can flag patients at risk of deadly heart attacks years before they occur. Their new biomarker, called the Fat Attenuation Index (FAI), has been tested for the first time in a large study The study was published in the journal Lancet.
Heart attacks are usually caused by inflamed plaques in the coronary artery causing an abrupt blockage of blood getting to the heart. The challenge for doctors is knowing which plaques are most likely to cause blockages, and therefore which patients should be treated with more aggressive therapies.
The team has shown that the most dangerous plaques release chemical messengers which modify the surrounding fat. They have developed a technology that detects the inflamed plaques that are prone to cause heart attacks by analyzing CT images of the fat surrounding the arteries.
CT Coronary Angiogram
The study, supported by the British Heart Foundation and the NIHR Oxford Biomedical Research Centre, involved 3,900 patients from Europe (Erlangen, Germany) and the United States (Cleveland Clinic), who were followed up for ten years after they had a CT coronary angiogram. The FAI technology was found to predict fatal heart attacks many years before they happen, with a significantly superior predictive accuracy compared with other methods.
People with abnormal FAI had up to nine times higher risk of having a fatal heart attack in the next five years. Importantly, these patients would be the ideal candidates for aggressive medical therapy to prevent this from happening.
Every year, over 100,000 people die from a heart attack or related stroke in the UK alone, and heart disease and stroke remain the two biggest overall causes of death worldwide. No method allows for early detection of a potentially fatal build-up of plaque that could trigger a heart attack. With this new technology, clinicians would be able to identify those at risk of having a fatal heart attack in the next few years and take preventative steps before it strikes.
This new technology may prove transformative for primary and secondary prevention. For the first time, we have a set of biomarkers, derived from a routine test that is already used in everyday clinical practice, that measures what we call the "residual cardiovascular risk," currently missed by all risk scores and non-invasive tests.
This study highlights an entirely new way in which patients at risk for myocardial infarction or heart attack could be identified very early on. They very much need such novel approaches since a large part of all heart attacks to occur without any prior notice. This study and its results may add to our armamentarium to prevent heart attacks, which makes the results so exciting from a scientific and clinical point of view.
This is an exciting new technology which has the potential for providing a simple, non-invasive answer to detect patients at risk for future fatal heart attacks. More importantly, it highlights the incredible value of cross-continent collaboration to validate the findings in different populations.
Most heart scans are good at spotting blockages caused by large plaques, but not the smaller, high-risk plaques that are likely to rupture and cause a heart attack. This new technique could be a game changer allowing doctors to spot those "ticking time bomb" patients who are most at risk of a heart attack and getting them on to intensive treatment.
This would undoubtedly save lives. By using this non-invasive scan, we could prevent a lurking heart attack that might occur down the road. But it also potentially gives us a real-time window into tracking the effect of drugs on inflamed arteries, helping us to identify new life-saving therapies.
The strengths of the study include that CT examinations were done with various scanning protocols and derived from different CT vendors and scanner generations.