Research
At-home 'foot-recognition' AI scanner can prevent heart failure hospitalisations
A home device which scans someone’s feet as soon as they get out of bed in the morning could keep people with heart failure out of hospital, according to research presented at the British Cardiovascular Society conference in Manchester.
More than a million people in the UK have heart failure which, when not fully controlled by medication or lifestyle factors, can lead them to be hospitalised.
Now an AI device with ‘foot recognition’, similar to face-recognition technology, could potentially flag when heart failure is becoming severe and life-threatening – delivering an alert 13 days on average before a person would end up in hospital.
Warning sign for severe heart failure
The wall-mounted device, which is roughly the size of a smart speaker, detects a build-up of fluid in the feet and ankles called oedema, which is one of the ‘big three’ signs heart failure is becoming severe, along with sustained weight gain and breathlessness.
This oedema occurs when the heart is not pumping blood around the body as well as it should.
The device, produced by a small Cambridge-based start-up company called Heartfelt Technologies, which takes 1,800 pictures a minute, images the foot and lower leg at multiple angles using AI detection of their precise position, then calculates the volume of fluid they contain.
Scanner triggers alert to health professionals
Researchers say the scanner can trigger an alert to a heart failure team when someone has oedema which is getting worse, so they can be advised to take rapid action like increasing their medication, which could keep them out of hospital.
Dr Philip Keeling, senior author of the study and a consultant cardiologist at Torbay and South Devon NHS Foundation Trust, said: “This device detects one of the big three warning signs for people with heart failure before they end up in hospital.
“Only about half of people admitted to hospital with heart failure currently get assigned an early review by a heart failure nurse who can check to see if they are suffering a harmful build-up of fluid because their heart is not working properly.
“Amid a shortage of heart failure nurses, a device like this can be like a virtual nurse, tracking people’s health.
“Living with heart failure can be overwhelming, with all the medications, medical tests and appointments, and the requirement to monitor your own health.
“This scanner, once it is installed, just automatically keeps an eye on you and alerts the health failure nurse, which is a huge relief.”
The FOOT study examining the scanner involved 26 patients across five NHS trusts, who had also been asked to weigh themselves regularly to track the progression of their heart failure.
Among those who had the scanner in their home for at least two weeks before it triggered an alert, three people were hospitalised with heart failure.
The alerts came between eight and 19 days before their hospitalisation – giving the scanner an average prediction time of 13 days, which researchers say is adequate time to take action to keep someone out of hospital.
No effort from user required
The foot scanner simply needs to be plugged into the mains, and records real-time images automatically. To ensure privacy, it only scans the legs to a height 50cm from the floor, taking in much of the lower leg, from the toes to just below the knee.
Professor Bryan Williams, our Scientific and Medical Officer, said: “This small study suggests a simple device could significantly improve outcomes for at-risk patients with heart failure by keeping them out of hospital.
“This study is a good example of how technology might aid earlier interventions and treatment, by allowing people to track a key sign of their heart health at home.
“Innovations with the potential to transform heart care in this way are a major part of the BHF’s goal to save and improve lives of people living with cardiovascular disease.”
The research was supported by the National Institute for Health and Care Research (NIHR).