What are the signs and symptoms of heart failure?

Heart failure may develop slowly over time. You may notice a variety of symptoms. For example, you may become breathless on walking, or find you need an extra pillow at night because you feel breathless when lying flat. You may also notice swelling around your ankles which may increase over time.

Other symptoms such as a poor appetite and low energy levels can be related to heart failure but they are also associated with other conditions.

However, the main symptoms of heart failure relate to the build-up of water in your body (fluid retention) and tiredness. It is important that you are able to recognise the early signs of retaining fluid so that you can tell your doctor.

These signs include:

Sudden weight gain

First thing every morning, after you go to the toilet but before you have breakfast, stand on your bathroom scales. Make a note of your weight. It is a good idea to keep a notebook or diary where you can record your weight each day. It is also important to weigh yourself at about the same time every day. A sudden weight gain of 2kg (4lbs) over 2 days is an early sign of retaining fluid.

Shortness of breath

Fluid building up in your lungs can make you feel breathless. There are two types of breathlessness that you need to know about:

  1. Breathlessness on exertion

Means that physical effort – doing something   makes you breathless.

For example, if you can usually walk comfortably to your local shops but over time find this less easy to do, it might be an early sign of fluid building up on your lungs and you should tell your (GP) family doctor.

  1. Breathlessness at rest

If you find you are breathless when sitting quietly in a chair, you may be retaining fluid.

If you need extra pillows at night because you feel breathless when lying flat, you may be retaining fluid.

If you wake suddenly gasping for air, it may be a sign of fluid on your lungs. People often describe this as a feeling of suffocation or drowning.

If you get any of these forms of breathlessness at rest, contact your heart failure clinic or GP immediately.


Fluid building up in your lungs can cause a cough. If you notice a cough keeping you awake at night or if you are coughing up white frothy sputum (phlegm), there may be fluid building up in your lungs. Again, tell your doctor without delay.

Swollen ankles

You may notice that your ankles and legs become swollen during the day. If you press on your shinbone just above your ankle, you may notice your thumb leaves a dent in your flesh. This is a sign that you are retaining fluid and you should tell your GP.

Loss of appetite

Fluid can also build up in your gut and liver. This can make you feel full or bloated. It may also cause you to lose your appetite. If your gut is congested with fluid, your body may not be able to absorb your medication properly.


Extreme tiredness is a common symptom of heart failure as the heart is unable to supply enough blood to the muscles.


Some people may experience palpitations which is a feeling of your heart beating fast in your chest.