This will be a multicentre Phase IV study in which patients with chronic HF who are managed and followed by HF/heart functions clinics will be followed over a period of two years.

Clinic patients who are recruited into the study will have obligatory blood sampling for the surveillance measurement of NT-proBNP level every three months for a minimum of one year (4 samples). One-half of the subjects in each clinic will be randomized to have these NT-proBNP values made known to the attending clinic physicians and nurses, the other half will have these values blinded. During the study, attending clinic physicians can order open-label NT-proBNP or BNP assays, if available in their institution, to assist the management of their patients if they feel it is clinically needed.

Once an eligible clinic patient is identified, written informed consent will be obtained. All patients will have blood drawn for the measurement of NT-proBNP immediately after consent is obtained. The patient will then be randomized to either the usual care or NT-proBNP arm.

For each patient enrolled into the study the attending physician will ensure obligatory blood sampling for the measurement of NT-proBNP level every three months for a minimum of one year (4 samples). Conventional measures used in programmed management settings including history taking, physical and radiographic examination and echocardiography will also be undertaken as per clinical practice. Patients from both arms will be treated with the same conventional measures.

One-half of the subjects in each clinic will be randomized to have these NT-proBNP values made known to the attending clinic physicians and nurse practitioners. The other half (Usual Care) will have these values blinded. During the study, attending clinic physicians can order NT-proBNP or BNP assays, if available in their institution, to assist the management of their patients if they feel it is clinically needed. Demographic variables such as age, gender, BMI, serum creatinine, and eGFR will also be collected in both arms. A dedicated research coordinator based in St. Michael's Hospital, the core centre, will monitor patients, data and blood sample collection from all participating clinics. NT-proBNP will be measured on site in clinics with the facility to measure NT-proBNP. For clinics that do not have the facility, the samples will be shipped to the core centre for measurement and the results will be provided to the clinic within one week for those patients who are randomized to open-label NT-proBNP. The research coordinator, via close communications with the clinic nurses and physicians, will ensure the process is immaculately executed and blinding is maintained.

All patients will be followed every three months for a minimum of one year (4 samples) and will include an initial evaluation (Visit 1) along with four follow-up visits in the HF/heart functions clinics (Visits 2 - 5). A clinic visit will be requested for those patients having experienced a serious adverse event since Visit 1.

Inclusion Criteria:

• Age ≥ 18 years of age
• NYHA class II-IV heart failure
• Followed in a programmed heart failure (HF) management setting

Exclusion Criteria:

• Life expectancy <1 year due to causes other than HF such as advanced cancer
• Any other conditions that may render the patient ineligible according to the investigator's judgment