Feasibility Study of a New Peripheral Oedema Monitor for Heart Failure

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.

The patient will be asked to stand on standard medical weighing scales, to measure their weight.

A member of the research team will assess the severity of the peripheral oedema on a scale of 1-5.

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.

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.

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.

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.