Feasibility Study of a New Peripheral Oedema Monitor for Heart Failure

Evaluation of the Safety and Feasibility of a New Peripheral Oedema Monitor for Home and Clinical Use for Heart Failure Patients, Using the Heartfelt-1 Device

The study aims at assessing the usefulness of the Heartfelt1 device in patients suffering from heart failure, who have peripheral oedema. The device is non-contact and does not requires patient compliance to work. It gives an output reading of the patient's lower leg volume.

During the study, this measurement will be compared to clinical standard and gold standard measurements as well as clinical grading of peripheral oedema.

Study Overview

• Status: Completed
• Conditions: Heart Failure, Diastolic; Edema Brain; Decompensated Heartfailure
• Intervention / Treatment: Device: Heartfelt-1; Device: Weighing scales; Other: Medical grading of oedema; Other: Baseline assessements; Device: Water displacement method; Device: Callipers measurements; Device: Measuring tape

Detailed Description

The Heartfelt-1 device is a CE (Conformité Européenne = European Conformity) mark medical device used to measure biometric parameters of the foot and lower leg. The study aims at assessing the usefulness in patients suffering from heart failure, who have peripheral oedema. Models used for the measurements of foot and lower legs have not yet been validated for this group of patients, who are likely to have feet with abnormal surface contours and appearance secondary to oedema. Peripheral oedema can be a leading indicator of heart failure de-compensation which can lead to hospitalisation of patients, and therefore the device could be a useful clinical tool to monitor patients in their home. The Heartfelt-1 device has the ability to recognise the patient's feet (amongst an average size household setting), and trigger automatically the measurements when the feet are naked (for example as the patient goes in and out of bed). This makes the device an obvious choice for patients with compliance issues with current methods of monitoring (e.g. daily use of weighing scales) and treatment (e.g. diuretics) if it could be validated in this patient group.

The study has two general aims:

The first is to collect a time-series of data on inpatients with peripheral oedema caused by heart failure, as they receive intravenous or oral diuretic treatment to remove excess fluid and achieve optimal body weight and fluid balance. This data will be used both to determine the attainable resolution of foot biometric measurements on a patient as their fluid status changes, and also to further develop the algorithms used in the device and make them usable on a wide range of feet/lower legs which have been deformed by oedema. The data required for this study are images taken using the Heartfelt-1 device, as well as validation measurements such as the figure of eight using a medical grade tape measure, callipers, or the water displacement method using a volumetric gauge, at multiple time-points whilst the peripheral oedema reduces.

The second, on a second group of stable ambulatory (Heart Failure) HF patients with variable levels of oedema, is to evaluate the performance of the Heartfelt-1 device in determining foot biometric parameters one a wide range of patients at a single point in time. Patients with stable chronic heart failure will have their foot/lower legs measured by the Heartfelt-1 device, as well as standard medical measurement (figure of eight using a medical grade tape measure, callipers) and gold standard measurement (water displacement method using a gauge), as well as the patient's weight and a clinical grading of oedema. These will be compared and an estimate of the accuracy of the Heartfelt-1 device over this wider patient group can be extrapolated.

• Study Type: Observational
• Enrollment (Actual): 70

Contacts and Locations

Study Locations

• United Kingdom
  • London, United Kingdom, SW3 6NP
    • Royal Brompton Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 16 years to 97 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Non-Probability Sample

Study Population

Adults able to give consent to take part in the study

Description

Inclusion Criteria:

• Inpatients with admission for de-compensated heart failure requiring increase or initiation of diuretic therapy for fluid congestion.
• Patients attending cardiology outpatients at the Royal Brompton hospital with a diagnosis of heart failure and fluid retention.
• Cardiology patient without fluid retention (cardiology controls) Non-Cardiology patient without fluid retention (controls)

Exclusion Criteria:

• Patients unable to provide informed consent.
• Unstable arrhythmias in previous 48 hours
• Systolic BP<90mmHg or need for inotropic support
• Ulceration on lower limbs (below shin) - excluded from water displacement but could have image recording and calipers
• Inability to transfer from bed to chair
• Patients with broken skin or cellulitis will not have their foot volume measured using the water displacement equipment to reduce the risk of infection for the patient and other participants.

Study Plan

How is the study designed?

Design Details

• Observational Models: Case-Control
• Time Perspectives: Prospective

Number of groups / cohorts

4

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
20 outpatients with peripheral oedema; 20 outpatients with clinically detectable peripheral oedema for 1 set of measurements.	Device: Heartfelt-1; The patients will stand in front of the Heartfelt-1 in order for images to be captured and the volume of their lower legs measured.; Other Names: HF-1; Device: Weighing scales; The patient will be asked to stand on standard medical weighing scales, to measure their weight.; Other: Medical grading of oedema; A member of the research team will assess the severity of the peripheral oedema on a scale of 1-5.; Other: Baseline assessements; At the point study participants are recruited, their age, sex, diagnosis, aetiology of heart failure, LVEF (Left ventricular ejection fraction), medical and device therapy, time since diagnosis, BNP (B-type Natriuretic Peptide), CRP (C-Reactive Protein), renal function (EGFR), Haemoglobin, albumin and urinalysis will be assessed unless recent (less that 6 months old) results are available. The number of Heart failure hospital admissions in the last 2 years, LACE score, co-morbidities will also be noted.; Device: Water displacement method; This will involve filling a gauge with lukewarm water (27-35oC +-2oC) up to the appropriate level. The appropriate level is determined by the water stabilising after some has flown out of the gauge into the waste bucket. Once the water level is stable the patient, who is sitting on a chair will be gently plunging the foot (naked) in the gauge until their foot is flat on the bottom on the gauge. The water flowing out of the gauge into the measuring bucket will be collected until the flow of water stops. Four small marks with non-toxic /non-permanent pen will be made on the lower leg of the patient to indicate where the water level was at. The water which has been collected in the measuring bucket will be weighted with precision scales to determine the volume of water displaced by the insertion of the foot. The patient's foot will then be dried.; Device: Callipers measurements; This will involve making 4 marks on one of the foot/lower leg (small cross) using non-toxic / non- permanent pen. The measurement will consist of making 6 measurements between those marks using callipers, and reporting the distance on a calibrated tape.; Device: Measuring tape; The measurements taken using a medical tape measure will involve the circumference of the ankle to be measured as well as the circumference at the level of the arch of the foot. The medical tape used will be a CE marked disposable medical measuring tape to minimise the risk of infection. The measurements will be done on both feet.
20 cardiology controls; 20 outpatients with heart failure without clinically detectable peripheral oedema (control group) for 1 set of measurements.	Device: Heartfelt-1; The patients will stand in front of the Heartfelt-1 in order for images to be captured and the volume of their lower legs measured.; Other Names: HF-1; Device: Weighing scales; The patient will be asked to stand on standard medical weighing scales, to measure their weight.; Other: Medical grading of oedema; A member of the research team will assess the severity of the peripheral oedema on a scale of 1-5.; Other: Baseline assessements; At the point study participants are recruited, their age, sex, diagnosis, aetiology of heart failure, LVEF (Left ventricular ejection fraction), medical and device therapy, time since diagnosis, BNP (B-type Natriuretic Peptide), CRP (C-Reactive Protein), renal function (EGFR), Haemoglobin, albumin and urinalysis will be assessed unless recent (less that 6 months old) results are available. The number of Heart failure hospital admissions in the last 2 years, LACE score, co-morbidities will also be noted.; Device: Water displacement method; This will involve filling a gauge with lukewarm water (27-35oC +-2oC) up to the appropriate level. The appropriate level is determined by the water stabilising after some has flown out of the gauge into the waste bucket. Once the water level is stable the patient, who is sitting on a chair will be gently plunging the foot (naked) in the gauge until their foot is flat on the bottom on the gauge. The water flowing out of the gauge into the measuring bucket will be collected until the flow of water stops. Four small marks with non-toxic /non-permanent pen will be made on the lower leg of the patient to indicate where the water level was at. The water which has been collected in the measuring bucket will be weighted with precision scales to determine the volume of water displaced by the insertion of the foot. The patient's foot will then be dried.; Device: Callipers measurements; This will involve making 4 marks on one of the foot/lower leg (small cross) using non-toxic / non- permanent pen. The measurement will consist of making 6 measurements between those marks using callipers, and reporting the distance on a calibrated tape.; Device: Measuring tape; The measurements taken using a medical tape measure will involve the circumference of the ankle to be measured as well as the circumference at the level of the arch of the foot. The medical tape used will be a CE marked disposable medical measuring tape to minimise the risk of infection. The measurements will be done on both feet.
10 in-patients peripheral oedema; 10 in patients hospitalised as a result of heart failure and fluid congestion with peripheral oedema, those patients will have several sets of measurements taken over time to measure the reduction of peripheral oedema which is likely to show common features with the formation of peripheral oedema.	Device: Heartfelt-1; The patients will stand in front of the Heartfelt-1 in order for images to be captured and the volume of their lower legs measured.; Other Names: HF-1; Device: Weighing scales; The patient will be asked to stand on standard medical weighing scales, to measure their weight.; Other: Medical grading of oedema; A member of the research team will assess the severity of the peripheral oedema on a scale of 1-5.; Other: Baseline assessements; At the point study participants are recruited, their age, sex, diagnosis, aetiology of heart failure, LVEF (Left ventricular ejection fraction), medical and device therapy, time since diagnosis, BNP (B-type Natriuretic Peptide), CRP (C-Reactive Protein), renal function (EGFR), Haemoglobin, albumin and urinalysis will be assessed unless recent (less that 6 months old) results are available. The number of Heart failure hospital admissions in the last 2 years, LACE score, co-morbidities will also be noted.; Device: Water displacement method; This will involve filling a gauge with lukewarm water (27-35oC +-2oC) up to the appropriate level. The appropriate level is determined by the water stabilising after some has flown out of the gauge into the waste bucket. Once the water level is stable the patient, who is sitting on a chair will be gently plunging the foot (naked) in the gauge until their foot is flat on the bottom on the gauge. The water flowing out of the gauge into the measuring bucket will be collected until the flow of water stops. Four small marks with non-toxic /non-permanent pen will be made on the lower leg of the patient to indicate where the water level was at. The water which has been collected in the measuring bucket will be weighted with precision scales to determine the volume of water displaced by the insertion of the foot. The patient's foot will then be dried.; Device: Callipers measurements; This will involve making 4 marks on one of the foot/lower leg (small cross) using non-toxic / non- permanent pen. The measurement will consist of making 6 measurements between those marks using callipers, and reporting the distance on a calibrated tape.; Device: Measuring tape; The measurements taken using a medical tape measure will involve the circumference of the ankle to be measured as well as the circumference at the level of the arch of the foot. The medical tape used will be a CE marked disposable medical measuring tape to minimise the risk of infection. The measurements will be done on both feet.
30 control without cardiac conditions; less than 30 normal controls (healthy volunteers and patients without heart failure) in the age group 55 and above who agree to have images taken using the Heartfelt-1 device (not the whole set of measurements).	Device: Heartfelt-1; The patients will stand in front of the Heartfelt-1 in order for images to be captured and the volume of their lower legs measured.; Other Names: HF-1

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Volume as measured by the Heartfelt-1 device	Within 3 months after patient recruitment or before the end of the study (whichever is soonest).

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Weight	Patient weight on the day	Within 3 months after patient recruitment or before the end of the study (whichever is soonest).
Distance measurements	Distance measurements on the foot / lower leg of the patient	Within 3 months after patient recruitment or before the end of the study (whichever is soonest).
Circumference and "figure of eight"	Lower leg / foot circumference and "figure of eight" measurement	Within 3 months after patient recruitment or before the end of the study (whichever is soonest).
Volume of the lower leg/foot	As measured using the water displacement method.	Within 3 months after patient recruitment or before the end of the study (whichever is soonest).
Medical grading of oedema	Medical grading of peripheral oedema on a scale 1-5	Within 3 months after patient recruitment or before the end of the study (whichever is soonest).

Collaborators and Investigators

• Sponsor: Heartfelt Technologies
• Collaborators: Royal Brompton & Harefield NHS Foundation Trust
• Investigators: Principal Investigator: Alexander Lyon, BCh PhD FRCP, Royal Brompton and Harefield NHS Foundation Trust

Publications and helpful links

General Publications

• Chausiaux O, Williams G, Nieznanski M, Bagdu A, Downer P, Keyser M, Husheer S. Evaluation of the Accuracy of a Video and AI Solution to Measure Lower Leg and Foot Volume. Med Devices (Auckl). 2021 Apr 13;14:105-118. doi: 10.2147/MDER.S297713. eCollection 2021.

Study record dates

Study Major Dates

• Study Start (Actual): January 15, 2017
• Primary Completion (Actual): June 13, 2017
• Study Completion (Actual): June 13, 2017

Study Registration Dates

• First Submitted: December 5, 2016
• First Submitted That Met QC Criteria: December 12, 2016
• First Posted (Estimate): December 15, 2016

Study Record Updates

• Last Update Posted (Actual): October 13, 2021
• Last Update Submitted That Met QC Criteria: October 5, 2021
• Last Verified: October 1, 2021

More Information

Terms related to this study

• Keywords: Heart Failure; Edema; Oedema; Decompensated Heartfailure
• Additional Relevant MeSH Terms: Heart Diseases; Cardiovascular Diseases; Heart Failure; Edema; Heart Failure, Diastolic
• Other Study ID Numbers: RBH01

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: No
• IPD Plan Description: We are not planning to share individual participant data with other researchers.