Atrial fibrillation ablation

for AF is an effective method to control heart rhythm. This procedure often leads to symptomatic improvement, with success rates estimated to be up to 80% depending on factors such as AF duration, cardiac chamber size, and comorbidities. Over time, approximately 30-50% of individuals may require additional procedures as the heart may heal at previously treated sites or new areas may arise. Following successful ablation, it is often possible to discontinue medications used to control heart rhythm. The majority of individuals experience a significant reduction in AF occurrence and better control of the condition after undergoing ablation.

Is there more than one way to perform AF ablation?

Yes, AF ablation can be performed from the inside of heart chambers (Endocardial) or from the outside (Epicardial).

Standard AF ablation is performed from the inside and could use one of 3 modalities that are currently available. These are heat (radiofrequency / RF), cold (Cryoablation / Cryo) or electrical (Pulsed Field Ablation – also called PFA). PFA is the most recent modality. These modalities have their individual strengths and weaknesses but largely considered equivalent to one another.

Epicardial / Surgical AF ablations are performed by cardiac surgeons which is considered in people undergoing concomitant cardiac surgery if there is history of AF. Standalone surgical AF is considered in select circumstances.

What are the distinctions between initial and repeat / redo AF ablation?

Achieving better control of arrhythmia often necessitates multiple procedures for each individual. The need for repeat procedures may arise shortly after the initial AF ablation or years later. The approach to a repeat procedure depends on the specific rhythm issue and the findings during the procedure; it’s not predetermined.

In addition to AF, individuals might also present with other types of arrhythmias, such as atrial flutter (typical or atypical) and atrial tachycardia, which can be addressed concurrently during the ablation.

During each ablation procedure, there are several possible steps that can be taken. Below is an example of an escalating series of ablations:

EXAMPLE:

• Step 1: Isolation of Pulmonary Veins
• Step 2: Isolation of Posterior Wall
• Step 3: Isolation of Superior Vena Cava (SVC)
• Step 4: Creation of Anterior or Mitral Line
• Step 5: Ablation of Complex Fractionated Electrograms (CFE)

Each individual may undergo any combination of these steps during their ablation procedure. Typically, Procedures 1 and 2 focus on achieving Step 1.

For instance:

What are the risks of having an AF ablation?

They include but are not limited to the following.

Common risks and complications (more than 5%) include:

• Bruising bleeding at the puncture site. Bruising can extend beyond the puncture site and can take a few weeks to improve in some cases.

Uncommon risks and complications (1- 5%) include:

• Development of another arrhythmia
• Bleeding related to the groin puncture site or injury to an artery in the groin. This (rarely) may need surgery and or blood transfusion
• Chest pain / Pericarditis. This is an inflammation of the heart sack that can cause chest pain for some weeks after the procedure and is easily managed with anti-inflammatory medications

Rare risks and complications (less than 1%) include:

• Fluid around the heart called a “pericardial effusion” which may need to be drained thru a tube under the breast bone or “sternum”
• A stroke. This may cause long term disability (0.5%)
• Requirement for a pacemaker following the procedure
• Injury to the food pipe related to the ultrasound or temperature probe used during the procedure.
• Injury to the urinary tract if a urinary catheter is required for the procedure.
• Damage to the phrenic nerve that controls the diaphragm (breathing muscle) called phrenic nerve palsy.
• Atrial oesophageal fistula. A hole forms between the gullet and heart. This can cause vomiting of blood and a stroke. This may be life threatening.
• Narrowing of the veins from the lungs to the heart called pulmonary vein stenosis.
• Damage to normal electrical system requiring a permanent pacemaker
• Death because of this procedure is rare

What are the costs involved with an ablation?

If you undergo this procedure as a public patient in a public hospital, Medicare will cover the expenses. If you choose to have this procedure in a private hospital, the standard hospital excess will still apply. It is common for anaesthetists to have additional costs that we recommend you address before your scheduled procedure.

How do I prepare for an ablation?

Before your procedure, you will receive a letter containing instructions and necessary steps to follow. This will include the date of admission, fasting guidelines, medications to discontinue, and items to bring along. Typically, you will need to have recent kidney and blood count tests before the procedure. As a general rule, refrain from eating or drinking anything for at least 6 hours prior to the procedure. It is important to consult your doctor regarding your regular medications. In most cases, blood thinners are continued for AF ablation procedures. However, if you are taking SGLT2 medicine for heart failure or diabetes, you will need to discontinue them at least 3 days before the surgery. Lastly, it is advisable to leave any valuable personal belongings such as jewellery at home.

What happens when you arrive at the hospital?

Upon your arrival at the hospital for the procedure, you will typically be directed to the admission area of the cardiac catheter laboratory, where you will be officially admitted as a hospital patient. You will be asked to change into a hospital gown and securely store any valuable belongings. Some basic tests will be conducted, such as an ECG, recording of vital signs, shaving of the groin area, and insertion of a cannula in your arm to aid the procedure. Technologists will apply special stickers and wires to your chest and back. In most cases, a pre-ablation cardiac CT scan of the heart is performed to assist in guiding the ablation procedure. If you have this scan done externally, make sure to request a copy of the CD and bring it to the hospital with you.

The ablation itself will be conducted under general anaesthesia, which requires the presence of an anaesthetist. The anaesthetist will discuss their role with you. Additionally, you will need an arterial line to monitor your blood pressure throughout the ablation, which carries a certain level of risk for complications.

What happens during the procedure?

You will be transferred to the catheter laboratory and positioned on a narrow, firm bed beneath the X-ray machine. The anaesthetist will administer general anaesthesia to put you to sleep. Local anaesthesia will be applied to the groin area to numb it. Four small tubes called sheaths will be inserted into the vein in your right groin. Through these sheaths, catheters will be gently guided and advanced into your heart. The X-ray machine will assist in directing the catheters to the correct positions within your heart.

To check for any clots in the heart prior to the ablation, a specialized ultrasound camera known as a transoesophageal echo (TOE) probe will be inserted through your mouth and into your gullet, which lies adjacent to your heart. If a clot is detected, the procedure will need to be halted. The TOE probe will also guide the wires across the interatrial septum, a thin membrane, from the right side to the left atrium. During this process, a long needle is used to gain access across the septum. Additional blood thinners will be administered to further reduce the risk of stroke. Usually, the TOE probe is removed, and a temperature probe is inserted into the oesophagus to monitor for any elevated temperatures throughout the procedure.