Atrial fibrillation (AF) is a progressive condition that impacts more than 33 million people worldwide.
Without early intervention, progression of the condition is associated with a higher rate of cardiovascular admissions, heart failure hospitalization, and mortality, along with a reduced quality of life.
Fortunatley, we have some arrows in our quiver.
AF can be treated with medication or ablation
Medication
Drugs to control the rhythm of the heart is always the first line of treatment. However, the success rates for drugs to maintain sinus rhythm varies.
Medication include
- potent anticoagulation therapy to stop the blood from clotting (Dr Gopal discusses (in Afrikaans) the link beween AF, stroke risk en anticoagulants),
- and medication to regulate heart rhythm and heart speed, known as antiarrhythmic drugs (AADs).
Antiarrhythmic drug therapy (AAD) is currently the standard first-line treatment for patients with AF; however, AF recurs in approximately 50% of patients treated with AADs within a year of therapy onset.
Commonly used rhythm controlling drugs (AADs) are flecainide (Tambocor), propafenone (Rythmol), sotalol (SotaHexal) and amiodarone (Arycor, Hexarone).
AAD therapy frequently causes side effects that can lead many patients to discontinue treatment.
The most effective drug is amiodarone which maintains sinus rhythm after 3 years in between 50-80% of patients.
However, amiodarone is not usually the first choice of many doctors because of the side effects which includes thyroid disease (1%) pulmonary fibrosis (3%) and liver problems. Unlike with most drugs these side effects do not go if the drug is withdrawn.
Drugs are usually tried before catheter ablation because if they work then they are safer (except possibly amiodarone) and easier than catheter ablation.
More than half of patients with symptomatic AF do not experience a reduction in AF with antiarrhythmic drugs, effectively delaying their therapy and leaving a critical need for an alternative first-line treatment.
If AADs are not effective in maintaining a normal sinus rhythm, we have more treatment options with excellent outcomes, in our armitarium.
These options include various modalities of catheter ablation depending on the arrythmia, various types of pacemakers depending on the exact reason for restoring normal and synchronised rhythm and implantable cardioverter devices (ICD).
MINIMALLY-INVASIVE TREATMENT OF ARRHYTHMIAS: Catheter ablation
One method of treating arrhythmias is to destroy the cells that are causing the heart to beat irregularly using a catheter placed in specific locations inside the heart. This is called catheter ablation.
Radiofrequency energy is the most common energy source used to eliminate the abnormal heart beats except atrial fibrillation, where electroporation or cryo-ablation is now often the first choice of treatment.
As a precursor to treating the arrhythmia, the physician creates an electrical road map of the inside of the heart to help guide the placement of the ablation catheter. This road map is created by placing a catheter that records electrical signals from various locations in the heart. This catheter is called a mapping catheter.
The most important element in the mapping and ablation phase is to place the catheters in the correct location of the heart so that an accurate map is created and only the abnormal tissue is destroyed.
Catheter ablation options are:
- Electroporation ablation, also known as Pulsefield ablation for treating AF,
- Cryoballoon ablation (and other one-shot ablations) for treating AF and
- Radiofrequency ablation for treating all arrthythmias
First Cryo-ablation and now electroporation/Pulse field ablation has revolutionised the treatment of patients with atrial fibrillation.
Cryoablation uses cold energy (freezing) delivered through an inflatable balloon to create scar tissue to interrupt unwanted electrical pathways in the heart.
Pulse Field ablation uses electrical impulses at a specific frequency to target only heart cells, with no damage to any other cells.
The procedures are quick (one hour), relatively painless and allows for short hospital stays. The incidence of post ablation cardiac arrhythmias, not uncommon with radio frequency ablation (RF), is exceedingly rare with electroproration and cryoablation.
Read about all the Catheter ablation options in more detail.
Take a look at this video taken inside the theatre during catheter ablation.
Take home message in 4 steps:
1. Eelctroporation or Cryo-ablation is now the first line of treatment for a patient with AF
2. Refer patient with AF for ablation as early as possible for best outcomes
3. We follow a stepwise approach to minimise formation of scar tissue related to excessive ablation. Thus a patient with AF may need 2 – 3 ablation procedures.
4. Ablation in the hands of an experienced electrophysiologist is a safe and effective treatment modality.