A new AI stethoscope can detect three common heart conditions in just 15 seconds by picking up sounds imperceivable to the human ear.
The diagnostic tool—commonly seen hung around doctors’ necks—is set to revolutionise care once again after receiving its first major overhaul in its 200 year history.
It means GPs will be able to diagnose and treat patients at a much earlier stage— before they become dangerously unwell.
The stethoscope is used to listen to sounds within the body and has been a vital part of a doctor’s toolkit since it was invented in 1816.
But an AI version can do much more, including analysing tiny differences in heartbeat and blood flow and recording electrical signals in the heart at the same time.
A trial involving 205 NHS GP surgeries with 1.5million patients found it increases detection of heart failure at the early stage when someone first goes to their family doctor with symptoms.
Those examined using an AI stethoscope were twice as likely to be diagnosed with heart failure in the next 12 months, compared to similar patients who were not examined using the technology.
They were also 3.5 times more likely to be diagnosed with atrial fibrillation—an abnormal heart rhythm which can increase the risk of having a stroke.
A new AI stethoscope can detect three common heart conditions within just 15 seconds
And they were almost twice as likely to receive a diagnosis of heart valve disease, which is where one or more heart valves do not work properly.
Researcher Dr Patrik Bächtiger, from Imperial College London’s National Heart and Lung Institute and Imperial College Healthcare NHS Trust, presented his findings at the European Society of Cardiology annual congress in Madrid.
He said: ‘The design of the stethoscope has been unchanged for 200 years, until now.
‘So it is incredible that a smart stethoscope can be used for a 15-second examination, and then AI can quickly deliver a test result indicating whether someone has heart failure, atrial fibrillation or heart valve disease.’
Early diagnosis is vital for all three conditions, allowing patients to access potentially lifesaving treatments sooner.
Heart failure—where the heart is not pumping blood around the body properly— affects more than a million people in the UK.
In more than 70 per cent of cases, it is only diagnosed after they are rushed to hospital.
But half of these people will previously have had symptoms or contact with a primary care healthcare professional, representing a potential opportunity to detect their heart failure.
Experts say it could help patients diagnosed earlier receive potentially lifesaving treatments
The AI stethoscope was trialled with patients who showed any of three symptoms suggesting they were suffering from heart failure—breathlessness, fatigue or swelling of the lower legs and/or feet.
If found to be at high risk, they went on to have their diagnosis confirmed with a blood test for a hormone called BNP—which is at a higher level when someone has heart failure—and a heart scan.
The stethoscope project saw 12,725 patients examined using the technology.
These patients, within 96 surgeries in North West London, were compared to patients from another 109 surgeries in the area, where AI stethoscopes were not used.
The device, which is about the size of a playing card, is placed on a patient’s chest to take an ECG recording of the electrical signals from their heart, while its microphone records the sound of blood flowing through the heart.
This information is securely sent to a remote computer to be analysed by AI algorithms, which have been trained on health data from tens of thousands of people and can detect subtle heart problems a human would miss.
A test result, indicating whether the patient has been flagged as at-risk for heart failure or not, is sent straight back to a smartphone.
A separate algorithm can detect atrial fibrillation, which often has no symptoms and is a contributing factor to one in five strokes in the UK, but can be managed with blood-thinning medications.
Dr Sonya Babu-Narayan, clinical director at the British Heart Foundation and consultant cardiologist, said: ‘This is an elegant example of how the humble stethoscope, invented more than 200 years ago, can be upgraded for the 21st century.
‘We need innovations like these, providing early detection of heart failure, because so often this condition is only diagnosed at an advanced stage when patients attend hospital as an emergency.
‘Given an earlier diagnosis, people can access the treatment they need to help them live well for longer.’
However, 70 per cent of GP surgeries given smart stethoscopes in the study stopped using them, or used them infrequently, after 12 months and two-thirds of people identified by the AI stethoscope as having suspected heart failure did not in fact have it, when given a further blood test or heart scan.
The researchers say efforts to integrate the technology into GPs’ existing routines would be needed to roll the technology out more widely and highlight the device is picking up cases that would otherwise be missed.
They stress that the AI-stethoscope should be used for patients with symptoms of suspected heart problems and not for routine checks in healthy people.
The study, called TRICORDER, was funded by the National Institute for Health and Care Research (NIHR), British Heart Foundation and Imperial Health Charity.
Researchers supplied GP practices with an AI stethoscope manufactured by Californian company Eko Health.
They next plan to roll out the technology to GP practices in Wales, South London and Sussex.
Professor Nicholas Peters, senior investigator from Imperial College London and consultant cardiologist at Imperial College Healthcare NHS Trust, said: ‘Our study shows that three heart conditions can now be identified in one sitting.
‘Importantly, this technology is already available to some patients and being widely used in GP surgeries.’
Professor Mike Lewis, Scientific Director for Innovation at the NIHR, said: ‘This tool could be a real game-changer for patients, bringing innovation directly into the hands of GPs.
‘The AI stethoscope gives local clinicians the ability to spot problems earlier, diagnose patients in the community, and address some of the big killers in society.’
