Monitoring Oedema in Heart Failure to Improve Function and Reduce Hospitalisation Risk

This study will evaluate the Heartfelt device, a novel, passive monitoring system that detects early signs of fluid build-up in patients (oedema) with heart failure by measuring changes in foot and lower leg volume through capture of 3D images. The trial will assess whether this device, when added to standard NHS care, improves quality of life and reduces heart failure-related events compared to standard care alone.

Heart failure often causes fluid build-up in the legs and lungs, leading to symptoms like swelling and breathlessness. Spotting these signs early is important to help prevent worsening health and hospital admissions. While patients are encouraged to monitor their weight and symptoms, this can be hard to keep up with. The study will involve 300 participants from at least 15 NHS hospitals and GP practices across the UK. People will be randomly placed into one of two groups: one will receive standard NHS care (including regular weight checks and symptom monitoring), and the other will receive the same care plus the Heartfelt device. The trial is partly blinded: participants may see technical messages (e.g. if the device goes offline), but only the group using the device will trigger clinical alerts. The Heartfelt device takes daily images of the feet to track changes in size, without the need for any extra effort from the user. If important changes are spotted, alerts are sent to the clinical team so they can act quickly. The study will look at quality of life, how often the device sends useful data, healthcare use, and how teams respond to alerts. It will also explore how easy the device is to use and whether it offers good value for money. Patients will help shape the study to make sure the findings are relevant and useful for future care.