Inclusion Criteria:  Written informed consent  Male or female over18 years of age Cohort A Meet European Society of Cardiology 1 (ESC) criteria for diagnosis of HF Undergoing clinically-indicated RHC Cohort B Established on haemodialysis for >90 days Undergoing haemodialysis with target volume removal ≥1.5 litres fluid Cohort C Meet ESC criteria for diagnosis of HF including heart failure Requiring treatment with intravenous (IV) diuretics Training Cohort Meet ESC criteria for diagnosis of HF including heart failure Requiring treatment with intravenous (IV) diuretics  Exclusion Criteria:  Unable to consent to inclusion in study due to cognitive impairment Allergies or skin sensitivities to silicone-based adhesive Skin breakdown or dermatological condition on the left chest or breast areas or chest wall deformity where the device is placed Pregnancy or breast-feeding Conditions that may confound congestion assessments COVID-19 infection.