Aortic stenosis: early signs and how to reach a diagnosis, including with AI

It is a well-established principle in medicine: early diagnosis is the first step towards effectively managing a medical condition. Aortic valve stenosis, the most common heart valve disease, is no exception to this rule; it is often only recognised once it has reached an advanced stage. In the future, however, a simple electrocardiogram combined with Artificial Intelligence could help identify those at risk even before symptoms appear. This promising breakthrough is certainly no small matter, given that we are dealing with an insidious condition.

A study published in the *European Heart Journal*—carried out by a team of researchers from Imperial College London, the Imperial College Healthcare NHS Trust and Shanghai Zhongshan Hospital, coordinated by Arunashis Sau and Fu Siong Ng. According to the results, AI could identify very early changes in the heart with a high degree of accuracy, even detecting in advance some signs that are currently recognised via echocardiography. “This is a very interesting prospect because it could allow us to select patients for closer monitoring and reach a diagnosis sooner – comments Italo Porto, Director of Cardiology at the IRCCS Policlinico San Martino AOM in Genoa and Professor at the University of Genoa. “Today, however, early diagnosis still depends primarily on attention to symptoms and a cardiological examination.”

Aortic stenosis is often an insidious condition. The early signs can easily be attributed to ageing or everyday tiredness: shortness of breath on exertion, reduced physical stamina, dizziness, easy fatigue or palpitations. “Many patients simply think they are getting older,” notes the expert. “In reality, the heart may be struggling to pump blood due to a valve that is narrowing.” In all cases, advancing age affects the health of the heart valves. Advanced age is in fact the main risk factor, given that aortic stenosis affects around 3% of the population over the age of 75. But it is not the only factor to consider. The likelihood of developing the condition may increase in the presence of high blood pressure, diabetes or other cardiovascular diseases. Finally, the negative impact of cigarette smoking should never be underestimated, as it has a specific effect on the risk of valvular disease.

The aortic valve regulates the flow of blood from the heart to the rest of the body. Over the years, it can become calcified and stiffen, gradually narrowing. When this happens, the left ventricle has to work harder and harder to push blood through an increasingly narrow opening. Over time, this can lead to heart failure, the resulting heart failure, and consequently a reduced quality of life. Unfortunately, it is important to remember that the heart tends to ‘adapt’ to this process in some way: the valve may take years or even decades to narrow, partly due to the calcifications that develop with age; the heart therefore tends to work harder to compensate for the defect, with the result that sometimes the person has no symptoms, or only minor complaints, for years.

This is why it is important to seek medical attention early on; although the condition can be difficult to recognise in its early stages, diagnosis is relatively straightforward. During the consultation, the doctor may detect a characteristic heart murmur on auscultation. At that point, the decisive test is an echocardiogram. “Echocardiography remains the gold standard,” concludes Porto. “It is a non-invasive test that allows for a precise assessment of the severity of the stenosis and enables the planning of the most appropriate treatment, which can now increasingly be carried out using minimally invasive procedures such as TAVI (i.e. transcatheter aortic valve implantation, ed.)”.