foot oedema observed over time study

Conditions: Heart Failure; Edema Leg

Summary: heart failure is the final common pathway of most forms of cardiovascular disease. in the united kingdom (uk), it affects around 900 000 people, causes or complicates around 5% of adult emergency hospital admissions and consumes up to 2% of total national health service (nhs) expenditure. an important part of discharge planning includes measures such as early follow up in order to prevent readmissions. the hallmark of heart failure is fluid retention and between 2009 and 2016, 43% to 50% of hospital admissions were associated with peripheral oedema. therefore, early recognition of this and treatment of the congestion may prevent hospital admissions. in clinical trials, management strategies have included patient education, telemedicine and remote monitoring. the main non-invasive method for detecting fluid retention has been the use of weight as a surrogate marker. the heartfelt device is an invention that uses a system of cameras in a compact device in order to generate 3 dimensional images of the feet and lower legs. the volumes can then be calculated and thus, changes in amount of peripheral oedema can be estimated. in a laboratory study performed by the heart failure team at the royal brompton hospital, there was good correlation between measurements made by heartfelt and a water displacement method. the resolution was as good as 20mls. by positioning the heartfelt device in the bedroom, automatic measurements can be made whenever the subject gets in and out of bed. images are only taken of the specified subject. data is censored so that the part of the body which is 50cm above the floor is not stored. encrypted, anonymised data is transmitted over the internet to the company's secure servers. personal identifiable data (participant name, address, age...) is stored on an encrypted hard drive, along with linkage information (device serial numbers) to associate the participant identifiable data with the data captured in the home. therefore, data collection is not only secure but entirely passive, which is a major advantage compared with previous non-invasive methods and it is applicable to a very wide range of compliant and non-compliant patients. our hypothesis is that the heartfelt device can directly detect the increase in peripheral oedema associated with heart failure decompensation and that, on average, the number of days with missing data collected by the heartfelt device will be lower than that of the weighing scales.

this is a phase 2 observational study during which subjects with chronic heart failure will be monitored in their home using the heartfelt device. the participant inclusion criteria will be those patients who are at high risk of hospital admission with a primary diagnosis of chronic heart failure or pulmonary oedema due to heart failure (hf), during either of which peripheral oedema was also noted. when heart failure decompensates, the amount of peripheral oedema that is clinically significant is unknown. the main objective of this study is to characterise the volume changes indicative of an increased risk for subsequent hospitalisation. subjects will also be provided with electronic, internet connected weighing scales that can transmit data and asked to weigh themselves daily. temporal changes in weight and volume will be compared. the study period will be 6 months and is the interval between installation of the heartfelt device and the study end. participants will be made aware that the data collected by the device will not be reviewed during the study and therefore that they should continue with reporting symptoms and issues as usual to their care team. in the event that it takes more than 2 years to recruit 20 participants, the study team will stop recruiting after 2 years so the study will be considered complete when all participants recruited up to that point have been monitored for 6 months. participants under the care of the trust have the following post diagnosis care: * patient education and training in self management * daily weighing * diuretic management * discharged under cardiologist * home visit by heart failure nurse (hfn) at 7-10d * urgent contact info for hf team * subsequent hf care by * hfn either at home or at community hospital * consultant cardiologist the heartfelt device will be provided in addition to these and not replace any of these activities. during the study period, data will be collected from the heartfelt device (passively) and a set of connected weighing scales (as and when the participant steps on the scales). any decisions made by the subject to seek medical help will not be influenced by the research team or the heartfelt device readings as those would be concealed to the participant and research team until appropriate review during the study. the participant will however be able to see the readings on the weighing scales as they step on it. retrospective analysis of the participant's notes which may indicate change in medications or care will be mapped to the foot volumes and weights collected. for those participants for whom decompensation occurs during the study period, the participants are seen by their healthcare professionals, and a clinical examination will be made as usual in a timely manner to determine the amount of peripheral oedema. this will be logged allowing retrospective comparison with the volume measurements. the temporal relationship between volume changes and decompensation will be investigated. the additional effect of clinical status data will be assessed. as the participation in a scientific study is known to modify behaviour, the information collected by scales and general reporting frequency of symptoms will be compared to the 6 months before the study and the 6 months after. the time to recruit participants should correct for any seasonal effect on this data.

Eligibility criteria:
inclusion criteria: 1. patients age 18 years or older. 2. patient able, agrees and signs the informed consent form. 3. patient with any heart failure diagnosis. 4. patient under the care of a cardiologist with heart failure nurse care. 5. patient with one prolonged inpatient stay 6. patient with significant peripheral oedema at admission 7. patient with significant weight loss following admission (at least 5kg weight loss). 8. patient has been discharged on at least furosemide 80mg or bumetanide 2mg/d exclusion criteria: 1. patient has bandages everyday 2. patient has an amputation of the foot 3. patient lacks capacity to consent 4. patient is of no fixed abode 5. patient has plans for intervention (crt, valves) 6. patient taking part in another study 7. patient must not been pregnant, and is taking relevant birth control\* * note that criteria (g) has been requested by the insurance for clinical trial cover. however we do not expect participants of this study to be trying to get pregnant (participants are expected to be over 55 years old).

Keywords: peripheral oedema peripheral edema heart failure decompensation weight hospital admissions