Heart failure stages explained

Being told you have heart failure can feel like a lot to take in. Understanding your condition can help you to feel more in control.

Heart failure does not mean your heart has stopped working. It means your heart is not pumping blood around your body as effectively as it should.

There are different causes of heart failure, such as a heart attack, high blood pressure, or because of other heart conditions.

You may hear your doctor or nurse talk about ‘stages of heart failure’ or ‘classes of heart failure’.

This refers to a classification system that helps to describe how bad your symptoms are and how much they affect the quality of your daily life. It can help your healthcare team plan the best treatment and support for you.

The most commonly used classification system is based on the New York Heart Association (NYHA) classification. It divides heart failure into 4 classes.

It’s based upon your physical ability to do things and your symptoms. These symptoms include:

• shortness of breath
• fatigue
• tiredness
• palpitations.

While it's not measured as part of the NYHA scale, the NHS also lists swollen ankles and legs – caused by a build-up of fluid – as one of the most common symptoms of heart failure.

It’s worth remembering that everyone experiences heart failure differently. You might find you move between these 4 classes.

When you're first diagnosed, you might feel you are class 3 or 4, but once you have your condition managed, this could change to a class 1 or 2 (see an explanation of each of class below).

Even if your condition is well managed, your symptoms may change and your class may change, even on a day-by-day basis. If you're worried about your symptoms changing, or what your classification means for you, speak to your doctor or nurse. 

The 4 classes of heart failure

Class 1: no symptoms

NHYA I is when you have no limitation of physical activity. This means that you do not experience any noticeable symptoms while you’re doing your usual daily activities. You can still do these activities without feeling abnormally breathless, tired or lightheaded.

Class 2: mild symptoms

NHYA II is slight limitation of physical activity. This means that you might start to notice some symptoms when you’re doing your normal activities.

You feel comfortable at rest, but everyday activities like climbing stairs, brisk walking, or carrying shopping might leave you feeling breathless, tired or faint.

You may also experience less common symptoms like a fast heart rate or palpitations.

This could be a sign that your heart is working harder to keep up with the demands of your body. Talk to your doctor if you notice these changes to see if you need adjustments to your treatment.

Class 3: significant symptoms

NYHA III is defined as comfortable at rest, but symptoms are present with less than ordinary physical activity. This means your symptoms are getting in the way of your daily life.

Everyday tasks, such as walking to the kitchen or getting dressed, may feel more difficult because of your symptoms.

For example, you may need to take breaks when you’re getting dressed or stop while climbing stairs because of your symptoms.

Class 4: symptoms at rest

NYHA IV is when you’re unable to carry out any physical activity without discomfort, and you experience symptoms even when you’re resting.

Any level of physical activity will make your symptoms worse. You might feel breathless, exhausted and uncomfortable even while sitting or lying down.

Treatments for heart failure

This includes medicines that can reduce how hard your heart has to work to pump blood round your body, such as:

• ACE inhibitors to widen your blood vessels and lower your blood pressure.
• Entresto (sacubitril valsartan), which works in a similar way to ACE inhibitors.
• Beta blockers to slow your heart rate.

If you have swollen legs and ankles due to fluid build-up (oedema) you may be offered a diuretic (sometimes called a water pill). And you might be advised to limit your fluid intake.

You may also be asked to track your weight every day, as this can be a sign that more fluid is building up in your body. If your diuretics are not working well, you might be given diuretics through a drip (intravenously).

As well as medicines, a pacemaker or ICD (implantable cardioverter defibrillator) can be helpful for some people with heart failure.

Certain people with heart failure may be offered a heart transplant. But it is not an option for everyone with heart failure, so you should speak to your medical team about it.

• Learn more about heart transplants.

End-stage heart failure

Doctors may use the term ‘end-stage heart failure’ when thinking about your treatment options and how well you’re managing with your condition.

It's difficult to tell if you are in end-stage heart failure, but signs include more frequent admissions to hospital and treatments not working as well as they have been.

You may also be in NYHA class 4 where treatments are not helping your symptoms.

However, if you're in class 4 that does not always mean you’re in end-stage heart failure.

If your medical team thinks you're in end-stage heart failure, they will discuss your treatment options and wishes with you. They will focus on easing your symptoms and making you more comfortable.

• Read more about heart failure and planning for the end of life.

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