Having a left-atrial appendage occlusion device fitted is an alternative treatment to long-term anticoagulation.

In some circumstances, long-term anticoagulation with warfarin or new oral anticoagulants (NOACs) may not be possible because of the high risk of bleeding complications, raised by other medical conditions. For example, if you have suffered bleeding in the stomach or bowel or had a stroke caused by bleeding then it may not be appropriate to anticoagulate you. 

Your case will be discussed at a multidisciplinary team (MDT) meeting in order to decide if an alternative way to reduce the risk of stroke would be indicated.

An alternative approach is to place a 'plug' in the part of the heart (the left-atrial appendage) where a clot is most likely (80–90 per cent of the time) to occur. This does not nullify your risk of stroke but it appears to be as effective as anticoagulation, without carrying the risk of bleeding complications. 

Prior to the procedure, and for up to the first six months after the procedure, you will be asked to take blood-thinning medications, such as a combination of aspirin and clopidogrel (which has a similar blood-thinning effect as aspirin) or warfarin. The exact blood-thinning drug regime will be decided according to your personal circumstances.

The admission arrangements and procedure are very similar to the AF ablation, which is discussed in more detail later on.

The placement of this 'plug' (there are two types of "plugs" currently available) is performed under general anaesthetic. Once you are anaesthetised we will pass an ultrasound tube (transoesophageal echocardiogram (TOE) via the mouth to the food pipe (oesophagus). 

This will allow us to see if there are any clots in the left atrium, specifically in the small pouch – the left-atrial appendage – where the "plug" is intended to be placed. If there is a clot, the procedure will be postponed until the clot has cleared with the help of blood-thinning medication.

If there is no clot we will place two small tubes into the veins at the top of your leg near the groin area. These tubes allow us to pass through another tube (catheter) that has the 'plug'. This is then crossed from the right atrium, through a small puncture, to the left atrium. Using the TOE again, we will place the plug in the best possible position in the left-atrial appendage. 

Once we are confident of its secure placement we will release the 'plug' from the catheter and it will remain there permanently. The 'plug'  stops blood from entering the appendage and by doing so it stops blood clot formation, reducing the risk of stroke.

When your procedure has been completed you will be taken to the recovery room. Once you are awake and your observations (blood pressure and heart rate) are stable, you will be taken back to the ward. You will spend the night on the ward where you will be attached to a cardiac monitor that will monitor your heart rhythm and blood pressure.

The following day you will have an echo in the morning and be reviewed by one of the medical team. Providing you remain well and your echo shows no fluid around the heart (pericardial effusion), you will be discharged home, usually in the afternoon.

You will be asked to come back in three months for a TOE. This will allow us to see the "plug" to make sure that it has blocked off the pouch completely. 

Complications of a left-atrial appendage device ('plug')

  • 0.5 per cent (1 in 200) risk of stroke
  • 1 per cent (1 in 100) risk of peripheral vascular damage (damage to the veins/arteries in your groin), when we put the tubes in your groin
  • 1–2 per cent (1–2 in 100) risk of tamponade (bleeding around the heart) that needs urgent drainage and may require a blood transfusion
  • 0.2 per cent (1 in 500) risk of cardiac surgery
  • 0.2 per cent (1 in 500) risk of plug migration requiring cardiac surgery
  • 0.1 per cent (1 in 1000) risk of death

In the rare circumstance where you cannot take any blood-thinning medication before and for the three to six months after the procedure, the plug approach will not be possible and an alternative approach may be recommended. Other options will be discussed with you in detail.

Atrial tachycardia is an abnormal heart rhythm which is usually seen in patients that have undergone heart surgery, have congenital heart defects or have undergone previous ablation procedures.

Atrial fibrillation is an abnormal heart rhythm. It is the most common heart rhythm disorder in the UK.

Arrhythmia team

The arrhythmia team includes: 

  • EP consultants
  • clinical nurse specialists
  • an arrhythmia pharmacist 
  • catheter laboratory technicians.  


Clinical nurse specialists

  • Natalie Crump 
  • Sue King
  • Sarah Plowright 
  • Alex Wise 

Arrhythmia pharmacist


Harefield Hospital
01895 828979

Royal Brompton Hospital
020 7351 8364 

Useful links

If you want to know more about arrhythmia, here are some helpful organisations and websites: