Professor Roy Gardner
Consultant Cardiologist, Golden Jubilee National Hospital, and Deputy Chair, British Society for Heart Failure
Diagnosis is often delayed, with people frequently mislabelled as having asthma or other lung diseases before consideration is even given to heart failure. This blood test could change that.
The treatment for heart failure has improved dramatically over the last 30 years, such that well-treated patients are living better and for longer. However, despite heart failure potentially affecting up to a million people in the UK, the diagnosis is often delayed with people frequently mislabelled as having asthma or other lung diseases before consideration is given to them having heart failure.
The more widespread use of N-terminal pro B-type natriuretic peptide (NT-proBNP) will help identify and treat patients with heart failure at an earlier stage.
What is the NT-proBNP test and what is it used for?
When the heart is stretched or under stress, it releases small proteins called natriuretic peptides. A high level of these proteins can indicate heart failure.
NT-proBNP can be checked by a blood test that is sent to the lab, but it is also available as a point of care test where the results is known, in around 10 minutes at a cost of only around £251.
A normal result virtually excludes heart failure in an untreated individual. NT-proBNP is the only natriuretic peptide recommended in the new National Institute for Health and Care Excellence (NICE) heart failure guidance1.
When would you want to check a patient’s NT-proBNP?
NT-proBNP should be checked if a patient is suspected of having heart failure. A negative result [particularly if their ECG (electrocardiogram/heart tracing) is also normal] virtually excludes heart failure. A positive result requires further investigation e.g. with a heart ultrasound [echocardiogram], and a review by a heart failure specialist if this scan is abnormal.
What’s your current clinical practice when it comes to NT-proBNP?
I look after patients with advanced heart failure, so most patients already have a diagnosis of heart failure when I see them. Our local heart failure service uses NT-proBNP. My doctoral thesis (2006) was on NT-proBNP as a prognostic marker in advanced heart failure and this work furthered the evidence as to the very strong prognostic power this peptide holds – certainly the most powerful prognostic marker in heart failure.
The treatment for heart failure has improved dramatically over the last 30 years, such that well-treated patients are living better and for longer.
Low concentrations suggest a very good outlook, and high concentrations [and particularly those that fail to come down with treatment] reflect a poor outlook. In these instances, it can help identify which patients require supportive/palliative care or, for suitable patients, we can consider highly specialised strategies such as heart transplantation (where low donor number seriously limit this possibility) or a left ventricular assist device (LVAD: ‘artificial heart’).
Why do you monitor your patients NT-proBNP levels?
To assess for the patient’s prognosis. Falling or low numbers are reassuring (for patients and their heart failure specialist!). If the NT-proBNP is rising, we need to ensure patients are on optimal doses of the correct heart failure therapy and are adhering to it.
What does monitoring a patients NT-proBNP level allow you to differently compared to if it were not available?
Imaging (such as echocardiography) often has long waiting lists. Once the diagnosis of heart failure is established, I monitor NT-proBNP as it is much cheaper and more readily available than performing serial echocardiograms, and much better at predicting the patient’s future. Avoiding unnecessary echocardiograms frees up this stretched resource for patients who need it most.
What do you think the impact will be of more widespread use of NT-proBNP in monitoring HF patients?
Although the natriuretic peptides have been in international guidelines for well over a decade (BNP was discovered in 1988!), it has been very slow to be adopted throughout the UK.
The treatment for heart failure has improved dramatically over the last 30 years, such that well-treated patients are living better and for longer. However, despite heart failure potentially affecting up to a million people in the UK, the diagnosis is often delayed with people frequently mislabelled as having asthma or other lung diseases before consideration is given to them having heart failure. The more widespread use of NT-proBNP will help identify and treat patients with heart failure at an earlier stage.
1 published September 2018: https://www.nice.org.uk/guidance/ng106
