Cardiac Catheter Ablation – A Safe and Effective Treatment for Atrial Fibrillation
A ‘cardiac catheter ablation’ may sound like a complicated and intimidating procedure, however, cardiac catheter ablations are a common treatment for Atrial Fibrillation (also known as AFib or AF). They are minimally invasive and their effectiveness is backed by high-quality global research
In this article:
What is Atrial Fibrillation?
Atrial Fibrillation is a common heart condition characterised by an irregular rhythm and is a common type of cardiac ‘arrhythmia’. The AFib rhythm starts in the atrium (the upper chamber of the heart, like a priming chamber of a pump) where rapid and chaotic electrical signals make the atrium quiver, or ‘fibrillate’. When the atrium is fibrillating, the usual rhythmic cycle of electrical energy to the lower chambers of the heart (the ventricles, or the main pump) is disrupted. The heartbeat becomes irregular – some people feel a fast heartbeat, others feel a slower beat, and others feel irregular thumps or bumps.
Symptoms can vary in range and severity, however, common symptoms include palpitations, chest pain, dizziness, fatigue, and shortness of breath which can impact a person’s ability to participate in their normal life activities.
AFib is caused by underlying changes in the electrical conduction in the heart and is associated with ageing, with genetics and lifestyle factors. Although the episodes of the fibrillating rhythm may come and go, AFib is a long-term condition due to those underlying changes. If untreated, it will gradually progress from occasional, to more frequent and persistent, to a permanent arrhythmia. AFib can also pose serious health risks, such as an increased risk of stroke. Although there is no cure, there are a variety of treatment options available, including medications, procedures, and some lifestyle changes that can reduce your risk of stroke as well as reduce the burden of AFib episodes.
Your doctor will be able to advise on a personalised treatment plan for you, that considers your AFib, any pre-existing health conditions, your genetic history, and other health and lifestyle factors.
One of those procedures that your doctor may recommend is a Cardiac Catheter Ablation. A cardiac ablation procedure is one common treatment used to help reduce AFib symptoms. In this article, we’ve consulted the Electrophysiologists at the AFib Institute to bring you a comprehensive guide to ablations. We’ve asked the common questions that people want to know – like what happens during a cardiac ablation, how to prepare for one, and what a typical recovery is like.
An Atrial Fibrillation Ablation is performed by a Cardiac Electrophysiologist – a Specialised Cardiologist.
Cardiac catheter ablations, including Atrial Fibrillation Ablations, are performed by a special type of cardiologist, called a ‘Cardiac Electrophysiologist’ or an EP. An EP is a cardiologist who has undergone additional years of training to specialise in diagnosis and treatment of rhythm problems of the heart, performing different types of ablation procedures, and implant and programming cardiac devices such as pacemakers and defibrillators. Cardiac Electrophysiologists are like the ‘electricians’ of the heart because they look after the heart’s rhythm or electrical activity.
What happens to my heart during a cardiac ablation?
Cardiac catheter ablations are minimally invasive procedures. This means that there is no major surgery involved. Instead, the whole procedure is done through a small cut in the upper thigh or groin, by using wires that are passed from the leg, through the veins, up to the heart and controlled remotely. It’s a bit like ‘keyhole’ surgery.
During the procedure, the Cardiac Electrophysiologist makes a small cut (or incision) in the groin, into the femoral vein. A guidewire and sheath are passed up to the heart to get to the right location, and once in place, then the electrical catheters can be put into place through that sheath. All of these are thin, flexible wires that the EP can ‘drive’ from a handle on the device at the groin, like the one pictured below.
An ablation is like a mechanic fixing a car’s engine... through the exhaust pipe
A simple way to visualise an ablation is to imagine a car with engine problems at a mechanic’s garage. The engine is broken, but the mechanic doesn’t open the bonnet to access the engine to repair it. He instead goes through the exhaust pipe, weaves his tools through the body of the car until he reaches the engine – and then performs his work with the engine still running!
How does the Cardiac Electrophysiologist know where to go?
The EP is guided by X-ray images of the heart and the electrograms that are monitored during the procedure. The operating table is surrounded by an x-ray machine that can be moved into place when needed, and the images are on display on monitors around the room. The EP can see on the X-ray the shape of the heart, and the catheters are designed so that they can be seen on the X-ray.
Additional guidance is provided by the electrograms – like extended ECGs, that are constantly running throughout the procedure. The EP is highly skilled at reading these and able to determine specific locations from the shapes of the electrogram waves – for the rest of us, it would be like watching a computer’s code of 0’s and 1’s, or the green symbols on the screens during the movie The Matrix.
In some cases, some EPs will also use an intra-cardiac ultrasound to identify their location in the heart. This is an additional wire that is fed into the heart, with a tiny ultrasound probe at the end. This provides direct images from inside the heart to help the EP.
Creating an AFib Electrical Map
The first step in an ablation is to create a map of the electrical activity of the heart. To do this, the EP uses X-ray images and electrograms and guides catheters with electrical sensors around the heart to create a ‘map’ of the flow of electrical activity of the heartbeat. This helps diagnose exactly where the AFib electrical signals are originating, and the specific lines for ablation.
The advanced technology in the catheter lab systems uses the signals to construct a 3-D image of the upper part of the heart. These are displayed on a monitor in the room and are often multi-coloured graphics. The EPs tend to concentrate mainly on the left atrium, where the pulmonary veins connect back to the heart and you’ll often be able to see these clearly in the graphic. This is the place where AFib commonly starts and is often the main location for ablation.
Performing an Ablation
Once they have oriented to the correct location, the EP uses the catheter to ‘ablate’ those specific locations in the heart. Ablation is using the catheter to deliberately create a ‘burn’ in the tissue along a fine line. In burning that area, it’s like creating a wall, or a dam, to stop the AFib electrical energy from passing through and starting an AFib episode. In time, the burned line heals with scar tissue – which is also an effective blockade to the abnormal electrical current. The pattern of ablation tends to be in a circle surrounding where the pulmonary veins connect to the atrium – though other techniques may sometimes be used.
The catheters can be very specific in where the burn line is created – and they are designed to cool down very quickly once finished so that generally don’t cause damage to surrounding areas of the heart.
There are two common types of catheter ablation procedures: Radiofrequency Ablation and Cryoablation
At the AFib Institute, our EPs have options of using heating or freezing energy to perform AFib ablations.
Radiofrequency ablations use hot energy to burn. There is a very fine tip at the end of the catheter that uses radiofrequency energy (a bit like a microwave) to create heat. The EP uses this to make a series of individual burns in a line where the ablation needs to occur – usually in a circle around the pulmonary veins within the atrium.
Cryoablation uses cold energy to burn. The cryoablation catheter has a special design with an inflatable balloon at the end. The EP positions the catheter near where the pulmonary vein enters the atrium and inflates the balloon. As the balloon inflates, it makes contact with the tissue in a circle around the pulmonary vein – precisely where the ablation needs to occur. Once the balloon is positioned correctly, then it uses extreme cold to create the ablation – down below minus 40 degrees Celsius.
At the AFib Institute, we have access to both of these technologies and use them widely. Both types of ablation have a similar success rate. The choice of type of ablation depends on several factors, related to you as a patient, as well as the availability of the technology at particular hospitals or session times, and the EP’s training or preference.
Is Cardiac Catheter Ablation for Atrial Fibrillation Safe?
Ablations have been performed by Cardiac Electrophysiologists (EPs) at the Queensland Cardiovascular Group (QCG) for over 30 years . Recently, these Cardiac Electrophysiologists have worked together to form the AFib Institute as a way of creating a better service for people with AFib through access to the latest evidence-based treatments and technologies, as well as providing a supported patient experience.
The AFib Institute’s EPs perform a large volume of safe and successful ablations every year. The AFib Institute’s Cardiac Electrophysiologists perform over 600 ablations per year, at multiple hospital locations across Queensland. The number of ablations we perform is increasing due to our growing patient needs, and as our team of qualified Cardiac Electrophysiologists expands.
If your ablation is performed at a well-regarded medical hospital, with highly-trained EPs, nurses, and technicians, like the team at the AFib Institute, then the risks of complications are very, very small. Extremely rare risks of ablations include bleeding, infection, and/or pain where the catheter was inserted.
There is a risk of blood clots (which is very rare), which can travel to the lungs or brain and cause a stroke. To reduce this risk, the EPs at the AFib Institute may perform a Transoesophageal Echocardiogram (or TOE) before starting an ablation. This enables them to obtain a clear picture of the inside of the heart and ensure that there are no existing blood clots that have formed inside the heart before they start the procedure.
It is very important for your blood to be “thin” to reduce the risk of clots and strokes. You will be fully anti-coagulated during and after the procedure, with blood thinners administered via your “drip”, along with your orally-taken blood thinners.
As with any medical procedure, you should discuss the risks and benefits of cardiac ablation with your doctor to understand if this procedure is right for you.
It is very important for your blood to be “thin” to reduce the risk of clots and strokes. You will be fully anti-coagulated during and after the procedure, with blood thinners administered via your “drip”, along with your orally taken blood thinners.
How do I prepare for an ablation?
You will receive specific information on what you need to do before your ablation from your Cardiac Electrophysiologist, our Cardiac Nurse, or the hospital where your procedure is booked. In general, these are some of the common recommendations.
- Healthy lifestyle changes before your ablation can increase success – Improving your health before your procedure can actually improve the success of your ablation, and your freedom from AFib episodes.
- Follow medication Instructions – Before your ablation, your doctor will give you specific instructions about your medications, and whether there are any new medications to start or other medications to stop before your ablation. Commonly, doctors would recommend avoiding your anticoagulant (blood-thinner) on the day of the procedure – though always consult your doctor for your specific instructions.
- Fasting – As we commonly do AFib Ablations with a general anaesthetic, you will usually need to fast from the night prior to your procedure. This means avoiding food so that you have an empty stomach during the operation.
- Pack for an overnight hospital stay – You will commonly need to stay at the hospital overnight after an ablation for monitoring. You will usually be discharged the following morning.
- Organise a drop-off and a pick-up – Typically, doctors advise you to avoid driving until at least 24-48 hours after your ablation – partly due to the effects of general anaesthetic remaining in your system, as well as due to discomfort in your groin or upper leg after the procedure.
- Discuss medical leave with your employer – Most people will organise a few days off work, even if work is an office job. People employed in more physically-intensive jobs may take longer to return to their work – talk to your EP about a recommendation for your specific circumstances.
- Look after yourself – After your ablation, a gradual return to exercise is recommended, along with following healthy-heart diet and lifestyle recommendations.
What should I expect on the day of my ablation procedure?
On the night before your procedure or the day of your procedure, you will check in at the hospital admissions desk. After the appropriate paperwork is completed, you will be brought up to the pre-operative area, usually by a nurse who will talk to you about the procedure.
You will meet your EP who will be performing the ablation and your anaesthetist, and you will have an opportunity to ask them both questions. You’ll have an ECG taken, and some blood tests, as a final check before your procedure.
Typically, you will have a cannula (a ‘drip’) put in one of your arms in preparation for your anaesthetic. Occasionally you will need the hair in your groin area shaved, to prepare the catheter insertion site.
You will then be taken through to the procedure room which is called the ‘EP Lab’, or the ‘Cardiac Catheter Laboratory’. It is a busy room, with a lot of equipment like computer screens, and people who will get you set up and comfortable on the procedure table.
You will also meet a team of cardiac scientists who will put the various sticky patches on your chest that measure your ECG and monitor you during the procedure.
After you are given a general anaesthetic, you will fall asleep. You will be completely covered with material drapes and your privacy will be protected throughout your procedure. There is usually just a small window in the draping to expose the skin in the groin where your EP will then put the catheter. Local anaesthetic is used around the groin – you are already asleep at this stage, however, it helps to reduce pain after the operation.
Your EP and their team will then sometimes perform a transesophageal echocardiogram to check that there are no blood clots in your heart, or to help guide catheter positioning in your heart. Then they will start your ablation procedure. The ablation can take anywhere from an hour up to two or three, or several hours.
Common recovery expectations after an ablation procedure for AFib
After the ablation is over, you will spend several hours in a recovery room in the hospital, where you will be monitored as you wake up. You will likely have a sore throat and may feel some chest tightness.
You will need to lie flat and relatively still for several hours after the ablation. This is to protect the small stitches in your groin area and reduce the risk of it starting bleeding. Some patients find it frustrating having to stay still for a few hours, but it is important to limit movement of your hip and groin area. There will be a dressing over this area, which is usually removed after 24 hours or so.
Other things to expect after an ablation include:
- You may have some swelling and bruising at the groin where the catheter was inserted, and it will be tender for possibly a week.
- Avoid physical activity for 24 hours. If you need to go up and down stairs in the first 24 hours, then lead with your good leg and keep the other leg relatively straight. Most people can return to normal activities within a few days after leaving the hospital.
- Avoid heavy or intensive physical activity for a few days.
- Avoid high-intensity exercise for 1 week.
- Avoid driving for 24-48 hours after the procedure – this is mainly so that your body can recover from the anaesthetic.
- You may need to take some time off work – how long may depend on your type of work. Your cardiologist can provide a medical certificate if you need one.
- Follow the important medication instructions given to you on the day that you leave the hospital.
- You can generally resume a normal healthy diet, and we encourage you to remain well hydrated.
- You will need to have a follow-up appointment with your cardiologist after the procedure. Please contact the AFib Institute at QCG to arrange that appointment if it has not already been made for you.
When to contact your doctor at the AFib Institute
Your recovery after an ablation is usually very smooth, however, there are some times that you need to contact your doctor.
If you’re experiencing pain in the chest or shortness of breath, then your doctor needs to know. If you feel that your heart has gone back into atrial fibrillation, your doctor needs to know about that too.
If you are mildly unwell and feel that you can pass on a message via contacting the AFib Institute clinic, we will guide you through what to do next.
If you feel very concerned or are feeling very unwell, you need to come into the emergency department of the hospital where you had the ablation.
What is the ‘blanking period’ after an ablation?
Many patients are eager to know if the ablation has been successful in treating their AFib. Unfortunately, it can take a while to know this answer.
Immediately after an ablation, the tissues in the heart will be irritated, and it will take a while for them to recover. The areas of ablation will slowly form scar tissue which is part of the benefit of the ablation and this can take weeks to months. As a result of the time it takes for the heart to settle and heal properly, it can take approximately three to six months after an ablation to reach the full benefit of the procedure. This period is commonly referred to as the ‘blanking period’.
During this time, an occurrence of atrial fibrillation doesn’t necessarily mean that the ablation has failed. The blanking period is a stabilisation period after an ablation, during which a patient’s AFib ‘quiets down’. This can particularly be the case for people who have more persistent AFib or had longer periods of AFib prior to the ablation.
Talk to your EP about any episodes of AFib you have in the 3-6 months after an ablation. Your EP may want to adjust your medication or sometimes they may want to do a cardioversion to bring you back to normal rhythm while you are healing.
You might need more than one ablation to manage your AFib
Don’t judge the success of your ablation too quickly. Be patient with your heart’s healing process, as the impact of ablation on AFib varies greatly between patients.
For many patients, a single ablation can be sufficient to provide relative freedom from AFib or a reduction in symptoms, particularly when performed before the AFib rhythm becomes too persistent.
But in a proportion of patients, it can take more than one ablation to create enough of a barrier to isolate the pulmonary veins. It could be because after the tissues healed and scar tissues formed there were still a few cells that were able to conduct, it could be that new circuits have established around the ablation area. You will have ongoing appointments with your EP over time so that they can monitor your progress, and adjust your treatment strategy if needed.
Where can I book a cardiac catheter ablation treatment in Queensland?
The decision to have an ablation is one that you make with a Cardiac Electrophysiologist, considering many aspects of your AFib, your general health, and your available treatment options.
If you would like to talk with one of the Cardiac Electrophysiologists at the AFib Institute, you can book an appointment at one of our South East Queensland locations within the Queensland Cardiovascular Group (QCG).
You can contact us via phone: 07 3016 1111 or via our online inquiry form here.
You will need a referral from your doctor.
Our doctors also perform ablations at Private Hospitals throughout Queensland including St Andrew’s War Memorial Hospital, Greenslopes Hospital, Mater Private Hospital, and St Vincent’s Hospital Northside.