Cardiac Ablation

What is cardiac ablation?

Cardiac ablation is a minimally invasive procedure used to treat patients with arrhythmias or irregular heart rhythms, especially for cases with fast or erratic heartbeats. The procedure is also called a catheter ablation.

How it works

Your doctor will make a small (approximately 3 – 4mm) cut in your groin, and carefully insert special flexible tubes (catheters) with electrodes into your blood vessel. They will then direct the catheters to specific locations in your heart to identify the abnormal sites causing the abnormal heart rhythm.

Once the abnormal area is found, the doctor will deliver heat (radiofrequency) or cold (cryoablation) energy to the tip of the catheter to destroy the small part of abnormal heart tissue that is causing the arrhythmia.

Types of cardiac ablation

Cardiac ablation broadly includes different procedures, specific to the type of irregular heart rhythm and its location in the heart:

• Atrial fibrillation (A-fib) ablation is a complex procedure that creates electrical lesions (using heat or freezing technology) to disconnect the electrical signals within the pulmonary veins (where A-fib usually starts) from the rest of the atrium.
• AV node ablation is sometimes used in patients with resistant A-fib who do not respond to other treatments. The procedure involves destroying the atrioventricular node with heat energy to electrically disconnect the upper and lower chambers of the heart, so A-fib cannot affect the main pumping chambers of the heart. If you undergo this procedure, you will need to have a permanent pacemaker inserted.
• Atrial flutter ablation corrects the electrical signals usually in the top right chamber (called the right atrium). The procedure has a high success rate of curing the arrhythmia.
• Supraventricular tachycardia (SVT) ablation refers to treatment for abnormally fast or erratic heartbeats in the heart's upper chambers. This arrhythmia can occur in people across all ages, including young children. Catheter ablation for SVTs is usually quite straightforward and has a very high success rate for long-term cure, without the need for medication.
• Ventricular tachycardia ablation corrects abnormally fast heartbeats occurring in your heart's lower chambers.

Cardiac ablation can be performed using:

• Heat (known as radiofrequency ablation)
• Freezing (known as cryoablation)
• High-voltage electrical pulses (known as pulsed field ablation)

Pulsed field ablation

Pulsed field ablation (PFA) is a non-thermal method of targeting abnormal areas of the heart causing irregular heart rhythm. Unlike conventional tools that heat or freeze heart tissue, PFA uses high-voltage electrical pulses during the treatment. This helps to improve treatment precision, reduce operating time, and allows for a safer operation, since PFA is cardiac tissue-selective and is able to spare structures adjacent to the heart.

Why do you need a cardiac ablation?

Cardiac ablation is one of the treatments to correct heart rhythm problems (arrhythmias), especially if you have a fast or erratic heartbeat.

You may need a cardiac ablation if:

• Your irregular heart rhythm causes you to:
  • Have unpleasant symptoms such as shortness of breath and palpitations.
  • Face an increased risk of stroke or cardiac arrest.
• Your body responds poorly to medicine used to control your heart rate or heart rhythm.

Clinical studies have demonstrated that ablation is more effective at restoring and maintaining a normal heart rhythm compared to medication. This may reduce the need for lifelong treatment and also the side effects associated with medication.

Who should not undergo cardiac ablation?

If cardiac ablation involves the use of radiation, a pregnant woman should not undergo this procedure to avoid posing risks to the foetus.

What are the risks and complications of cardiac ablation?

The possible risks from cardiac ablation are:

• Bleeding or infection at the entry point where the catheter was inserted
• Blood clots in your legs or lungs, which may lead to a stroke
• Damage to your blood vessel
• Damage to your heart valve, or puncture to the heart
• Narrowing or blockage of the veins that transfer blood from the lungs to the heart (pulmonary vein stenosis)
• New or worsening arrhythmia
• Slow heart rate that may require a pacemaker
• Stroke or heart attack

In very rare cases, cardiac ablation may lead to death.

You are more likely to face these complications if you are older or if you have other medical and heart conditions.

It is possible that the issue of irregular heart rhythm may return after the procedure. Performing the ablation again can permanently eliminate atrial fibrillation in some patients.

How do you prepare for a cardiac ablation?

Your doctor may order several diagnostic tests to assess your heart and overall health before proceeding with the ablation. These tests may include:

• Electrocardiogram (ECG) to analyse your heart rhythm
• Echocardiogram (Echo) to evaluate your heart structure and function
• Stress testing to see how your heart responds to exercise
• Blood tests
• Cardiac catheterisation or coronary angiography, to assess your coronary arteries
• Cardiac computerised tomography (CT) or magnetic resonance imaging (MRI) scans, to further evaluate your heart anatomy

You will also be asked to fast from food and drinks the night before your procedure, or for 6 hours before if the procedure is in the afternoon. This is to avoid any negative reaction to the anaesthesia that you will be receiving before the procedure.

Check with your doctor if you should stop taking any medication.

What can you expect in a cardiac ablation?

A cardiac ablation is a minimally invasive procedure.

Estimated duration

The procedure usually lasts between 1 – 3 hours depending on the type and complexity of the arrhythmia.

Before the procedure

You may be lightly sedated, or given general anaesthesia to keep you asleep during the procedure.

During the procedure

During the procedure:

• A nurse will attach electrocardiogram (ECG) electrodes on patches onto your back and chest. These help send signals to computers to guide your doctor during your ablation.
• Your doctor will make small cuts of approximately 3 – 4mm in your groin.
• Next, your doctor will insert special flexible tubes (catheters) through the small cut into a blood vessel (vein or artery) to reach the appropriate part of your heart.
• If required, a 3D mapping system can be used to help identify the exact site in the heart that is causing irregular heartbeats.
• Your doctor will activate electrodes on the tip of the catheter to burn or freeze a small spot of heart tissue so as to correct the irregular heartbeats. This may cause some discomfort.
• Once done, the team will remove the catheters and close the site where the doctor had inserted the catheters, or leave a pressure compression bandage to prevent any bleeding or bruising.

After the procedure

You will be moved to a recovery room where the team will monitor your vital signs.

As you recover from the procedure, you may experience the following:

• Soreness, which shouldn't last more than a week
• Tightness in your chest
• Lethargy, especially in the first few days
• Bruising from the catheter insertion
• Short-lived palpitations after the ablation, which usually settle

Care and recovery after a cardiac ablation

After the treatment, your doctor will most likely ask you to be hospitalised for 1 – 2 days. This allows your doctor to observe your condition and ensure that your heart is working normally.

Right after an ablation, you should avoid:

• Doing heavy physical activity for a week
• Driving for 48 hours after the procedure

Your doctor may also recommend that you participate in cardiac rehabilitation to help you improve your health and recover after heart surgery.

Your doctor may prescribe blood thinners for months after your procedure to reduce your risk of a stroke. They may also prescribe anti-inflammatory drugs.

You should call your doctor if:

• You have difficulty breathing with little to no exertion
• Your chest hurts
• Your heartbeat becomes irregular
• Your leg is numb
• The insertion site starts to bleed or bruise badly
• The puncture site swells