Left atrial appendage closure (LAA)

LAA image 1

This is a treatment to prevent stroke caused by blood clots forming in the left atrial appendage in patients who suffer from atrial fibrillation (AF) and other factors that increase the risk of stroke, particularly if they have difficulty managing blood thinning therapy.
Patients who have artificial heart valves or who are likely to need valve replacement may not be suitable.

LAA image 2

The left atrial appendage is a small, windsock-like pouch, which empties into the left atrium of the heart.

For patients with normal heart rhythm, the left atrial appendage squeezes rhythmically with the rest of the left atrium. This rhythmic contraction ensures that blood in the pouch is ejected when the left atrium empties into the left ventricle, where it is then pumped all over the body.

In atrial fibrillation that rhythmic contraction is lost and blood can collect in the left atrial appendage and form a clot.

For older patients, atrial fibrillation (AF) is a common rhythm disturbance where the top chambers of the heart (atria) do not beat regularly.

The symptoms of AF vary from mild fatigue to dizziness to chest pain or difficulty breathing. Some patients feel their heart palpitating, while others are unaware of the change in heart rate.  However, whether AF causes symptoms or not the blood inside the pouch (appendage) is not ejected as it is during normal rhythm and blood clots may form in the pouch as a consequence.

These clots can pass into the left atrium and then travel to the brain causing a stroke. It is estimated that the clots which cause stroke in patients with AF originate in the left atrial appendage 90% of the time.

Most patients who develop AF are required to take "blood thinners" such as warfarin for the rest of their lives to prevent blood clots forming. Warfarin can be a difficult medication to take as there are many interactions with food items, alcohol and other drugs.

The medication dose may need frequent review and blood testing is required at least monthly. There are also significant bleeding risks while taking warfarin, particularly as patients get older. Newer "blood thinners" which are easier to take are becoming available. The bleeding risks with the newer agents are less than with warfarin but still not negligible. 

LAA image 3

An alternative approach to reduce the risk of blood clot formation in the left atrial appendage is to remove the appendage from circulation by closing it off using a form of “plug” such as the Watchman device. 

How is the procedure performed?

  • The device is positioned via a catheter from the groin, which is placed in the left atrial appendage by crossing from the right atrium to the left (trans-septal puncture).
  • General anaesthesia is used because the procedure is monitored with transoesophageal echo as well as X-rays. (An echo probe in the oesophagus, or “gullet”, produces excellent pictures of the heart, especially the left atrium and the appendage).
  • There is no incision in the chest.
  • Recovery is rapid; most patients have a single overnight stay.
  • Most patients can stop warfarin after 6 weeks to two months. It can also be done in patient who cannot take warfarin or other blood thinners at all.

What will I experience during the procedure?

In some countries this procedure is done under local anaesthetic, but we feel that it is safer and more comfortable to use a general anaesthetic given that transoesophageal echo is an integral part of the procedure.  It is therefore like any other operation performed under general anaesthesia – you will not be aware of anything during the procedure.

How should I prepare for the procedure?

You will need a transoesophagel echo (TOE) a few days before the procedure to be sure that no blood clot is present in the appendage at the time of the procedure.

  • Fasting: You must not have anything to eat or drink six to eight hours before you procedure, unless the Anaesthetist tells you otherwise. You may continue to drink a small amount of clear fluids to take medications..
  • Medication: Please inform your cardiologist about all the medication you are taking. You cardiologist may advise you to stop taking some medication temporarily for a few days prior to your procedure e.g. blood thinners.
  • Allergies or previous reactions to contrast (x-ray dye): Please inform Intra staff at the time of booking your procedure if you have any known history of allergies, particularly allergies to x-ray contrast and seafood.
  • Diabetes: If you are a diabetic you should inform your cardiologist and Intra staff at the time of booking your procedure. You may need to discuss your insulin dose with your cardiologist.

Please bring with you any medication and any recent blood test results, ultrasound results or x-rays..

What happens after the procedure?

  • Normally the patient will have a single overnight stay in coronary care within the Mercy Hospital.
  • There is usually some bruising in the groin.
  • In patients taking warfarin or other blood thinners, these will be continued for another 6 weeks after the procedure until a follow-up echo shows satisfactory sealing of the left atrial appendage.  Patients who cannot take these drugs will remain on low dose aspirin and clopidogrel for 6 weeks.

What are the benefits and risks?


Recent clinical trials have shown that closing the left atrial appendage with a plug, for example the Watchman Device, which is inserted during a non-surgical procedure, are as effective as warfarin in reducing the risk of stroke in the short term and more effective in the long term.


The main potential risks of left atrial appendage closure occur at the time of the procedure. There is an extremely low likelihood of any complication afterwards if the procedure has been completed successfully.

The most important procedural risks are: injury to the heart during the trans-septal puncture or deployment of the device; and the entry of air into the circulation through the catheter used to insert the device. About 1 to 2 patients in 100 may require the placement of a tube into the sac around the heart to drain off blood that has leaked in because of injury to the heart.

Even more uncommonly an urgent heart operation may be required to drain off the blood if the leakage cannot be controlled by the insertion of a tube.  The entry of air into the circulation can itself be a cause of stroke, but this has become very uncommon now that the factors influencing it are better understood, and can be avoided by meticulous attention to the correct technique.