We invite the contribution of trials that meet the following criteria:

• Minimum dataset of 30 patients
• Patients aged 18 years old or older, with a diagnosis of acute or chronic heart failure of either ischaemic or non-ischaemic aetiology or inoperable valve disease
• Documented selection criteria
• Documented consent or waiver of consent following local institutional review board- approved procedure
• Baseline assessment includes medical history and New York Heart Association (NYHA) functional classification or a recognised assessment of index condition
• Outcome(s) assessed using one or more recognised measure(s)
• Monitoring procedures existed to validate the data