An aortic valve replacement is a major operation and will only be carried out if you're well enough to have surgery.

In the weeks before the procedure, you'll attend a pre-admission clinic for an assessment to check whether the operation is suitable.

This is also a good time to ask any questions you have about the procedure.

As part of this assessment, you may:

• have a physical examination
• be asked about your medical history, including any medication you're taking, any allergies you have and whether you have had a reaction to anaesthesia in the past
• have tests to check your general and heart health – these may include a blood test, X-ray, electrocardiogram (ECG) and echocardiogram

If you smoke, you'll be advised to stop in the lead up to your operation because this can reduce the risk of complications. 

You should be told when you need to stop eating and drinking before the procedure.

When you have the operation, it's likely you'll be in hospital for about a week, so you'll need to make some practical preparations in advance.

These include bringing clothes, toiletries and any equipment you use, such as a walking stick or hearing aid.

Read more about going into hospital and preparing for surgery.

An aortic valve replacement is carried out under general anaesthetic.

This means you'll be asleep during the operation and won't feel any pain while it's carried out. The operation usually lasts a few hours.

During the procedure:

• a large cut (incision) around 25cm long will be made along the middle of your breastbone to allow the surgeon access to your heart, although in some cases a smaller cut may be made
• tubes are inserted into your heart and major blood vessels, which are attached to a heart-lung (bypass) machine – this will take over the job of your heart during the operation
• medication is used to stop your heart and your main artery (aorta) is clamped shut – this allows your surgeon to open your heart and operate on it without blood pumping through
• the aorta is opened up and the damaged aortic valve is removed
• the new valve is sewn in place with a fine thread
• your heart is started again using controlled electric shocks before you're taken off the bypass machine
• your breastbone is joined up with wires, and the wound on your chest closed using dissolvable stitches

Before having an aortic valve replacement, you'll need to decide on the most suitable type of replacement valve for you.

There are 2 main types of replacement valve:

• mechanical valves made of synthetic materials
• biological valves made of animal tissue

Each type has advantages and disadvantages, which your doctor will discuss with you.

Mechanical valves

The main advantage of mechanical valves is that they're hard-wearing and less likely to need replacing.

This means they're often better for younger people having a valve replacement.

But there's a tendency for potentially dangerous blood clots to form on the valve, so lifelong treatment with anticoagulant medicine such as warfarin is needed to prevent this.

This will increase the chances of excessive bleeding from a cut or injury, particularly as you get older, and may not be suitable if you have had significant bleeding problems in the past.

Mechanical valves can also make a quiet clicking noise, which can be disturbing at first, but is easy to get used to.

Biological valves 

The main advantage of biological valves is that there's less risk of clots forming, so lifelong anticoagulant treatment isn't usually necessary.

But biological valves tend to wear out a bit faster than mechanical valves and may eventually need to be replaced after many years.

This means they're often better for older people having a valve replacement.