A home device that scans a person’s feet as soon as they get out of bed in the morning could help keep people with heart failure out of hospital, according to new research.
More than a million people in the UK have heart failure, which—when not fully managed by medication or lifestyle changes—can lead to hospitalisation.
Now, an AI-powered device with ‘foot recognition’ technology, similar to facial recognition, may be able to detect when heart failure is becoming severe or life-threatening.
The scanner can trigger alerts on average 13 days before a person is admitted to hospital.
The wall-mounted device, roughly the size of a smart speaker, detects fluid build-up in the feet and ankles—a condition known as oedema.
This is one of the “big three” indicators that heart failure is becoming more serious, along with sustained weight gain and breathlessness.
Dr Philip Keeling is senior author of the study and consultant cardiologist at Torbay and South Devon NHS Foundation Trust.
He said: “This device detects one of the big three warning signs for people with heart failure before they end up in hospital,” said
“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.”
Oedema occurs when the heart is not pumping blood effectively around the body.
The device was developed by Heartfelt Technologies, a small start-up based in Cambridge.
It captures around 1,800 images per minute, scanning the foot and lower leg from multiple angles.
Using AI to detect their precise position, it calculates the volume of fluid present.
Researchers say the scanner can alert a heart failure team when someone’s oedema is worsening.
In response, patients can be advised to take action—such as adjusting medication—potentially avoiding a hospital stay.
Keeling said: “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 heart failure nurse, which is a huge relief.”
The FOOT study assessed the scanner in 26 patients across five NHS trusts. Participants were also asked to weigh themselves regularly to track the progression of their heart failure.
Among those who had the device in their home for at least two weeks before it triggered an alert, three patients were later hospitalised with heart failure.
The alerts came between eight and 19 days before admission—giving an average warning time of 13 days, which researchers say is enough to intervene and prevent deterioration.
The device simply needs to be plugged into a mains socket and records real-time images automatically.
To ensure privacy, it only scans the legs up to 50cm from the floor, capturing the area from the toes to just below the knee.
Professor Bryan Williams, chief scientific and medical officer at the British Heart Foundation, 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.”