Catheter Ablation for atrial fibrillation

Symptom Relief: Many patients experience a significant reduction in AF episodes, improving quality of life.

Long-Term Benefits: Ablation can reduce the need for medications and lower the risk of heart failure.

Personalised Approach: The procedure is tailored to your unique heart anatomy and type of AF.

While catheter ablation is highly effective, several factors can influence outcomes:

Type of AF:

• Paroxysmal (intermittent) AF: Success rates are highest, with up to 70–80% of patients remaining free from AF after a single procedure.

• Persistent or long-standing AF: May require multiple procedures or additional strategies, such as posterior wall isolation.

Heart Anatomy:

• Enlarged atria or significant scarring (fibrosis) can make ablation more challenging and may reduce success rates.

Underlying Health Conditions:

• Conditions like obesity, sleep apnoea, high blood pressure, and diabetes can impact the long-term success of ablation. Managing these conditions improves outcomes.

Lifestyle Factors:

• Smoking, excessive alcohol consumption, and caffeine intake can trigger AF and may affect ablation success.

Experience of the Electrophysiologist:

• Centres with high procedure volumes and experienced specialists tend to achieve better results. The definition of a high volume operator is usually that they perform at least 50 AFib ablations a year.

Post-Ablation Care:

• Adhering to medications, attending follow-up appointments, and making lifestyle changes (e.g., regular exercise, healthy diet) are crucial for maintaining a normal heart rhythm.

1. Preparation

• Before the procedure: You’ll undergo a pre-procedural assessment, including blood tests, an ECG, and possibly a cardiac MRI or CT scan to map your heart’s anatomy.

• On the day: You’ll be asked to fast for several hours. The procedure is performed under local anaesthetic and mild sedation, or sometimes general anaesthetic, to ensure your comfort.

2. Vascular Access

• What happens: A small incision (about 3–4mm) is made, usually in the groin, to access the femoral vein.

• Catheter insertion: A thin, flexible tube (catheter) is inserted into the vein and guided toward your heart using X-ray or advanced 3D mapping systems.

• What to expect: You’ll receive local anaesthetic, so you may feel pressure or a dull ache, but not sharp pain.

3. Cardiac Access

• Navigating to the heart: The catheter is carefully threaded through the venous system into the right atrium.

• Mapping the heart: Electrodes on the catheter record electrical activity to identify the precise areas triggering AF.

• What to expect: You might feel your heart beating faster or slower as the catheter moves, but this is normal and closely monitored by your electrophysiologist.

4. Trans-Septal Access

• Why it’s needed: To reach the left atrium (where most AF triggers originate), the catheter must cross the atrial septum—the wall separating the heart’s left and right upper chambers.

• How it’s done: A specialised needle is used to create a tiny puncture in the septum.

• What to expect: You may feel a brief sensation of pressure or a skipped heartbeat, but this is temporary and not painful.

5. Ablation

• Energy delivery: Depending on the technique (cryo, radiofrequency, or pulsed field), energy is applied to the problematic areas, usually around the pulmonary veins, which are common sources of AF triggers.

• Real-time monitoring: Your electrophysiologist continuously monitors your heart’s electrical activity to ensure the ablation is effective.

• What to expect:

  • Cryoablation: You might feel a cold sensation in your chest.

  • Radiofrequency ablation: Some patients report mild warmth or discomfort.

  • Pulsed field ablation: Always under general anaesthetic, so generally painless, with minimal sensation.

6. Post-Procedure

• Immediate recovery: You’ll rest in a recovery area for 4–6 hours to allow the access site to heal and to monitor for any immediate complications.

• Going home: Most patients are discharged the same or next day.

• What to expect:

  • Mild chest discomfort or palpitations for a few days.

  • Bruising or tenderness at the catheter insertion site.

  • Fatigue for a few days—rest is recommended.

There are several advanced techniques used in catheter ablation, each with its own benefits:

Cryoablation

Uses extreme cold to create scar tissue, blocking abnormal electrical signals.

Radiofrequency Ablation

Uses heat energy to create small scars in the heart tissue, preventing erratic signals.

Pulsed Field Ablation

A newer technique using rapid electrical pulses to precisely target and ablate heart tissue without damaging surrounding areas.

If AF recurs after an initial ablation, further treatment may be necessary. Advanced strategies for redo ablation include:

Posterior Wall Isolation

• Why it’s used: The posterior wall of the left atrium can harbour AF triggers, particularly in patients with persistent AF.

• How it’s done: Additional lesions are created to electrically isolate the posterior wall, often using radiofrequency or cryoenergy.

• Success rates: Can significantly improve outcomes in patients who have not responded to initial pulmonary vein isolation.

Atrial Flutter Ablation

• Why it’s used: Atrial flutter is a common arrhythmia that can develop after AF ablation. It involves a rapid, organised rhythm in the right or left atrium.

• How it’s done: Ablation targets the cavotricuspid isthmus (for typical flutter) or other flutter circuits, restoring normal rhythm.

• Success rates: Highly effective, with success rates exceeding 90% for typical flutter.

Vein of Marshall Ethanol Ablation

• Why it’s used: The vein of Marshall, a remnant of fetal circulation, can act as a conduit for electrical signals that trigger AF.

• How it’s done: Ethanol (alcohol) is injected into the vein to block these signals. This is often combined with other ablation techniques.

• Best for: Patients with persistent AF or those who have not responded to standard ablation.