Atrial Fibrillation Ablation | Prof. Dr. Umuttan Doğan

Atrial fibrillation is a rhythm disorder in which the upper chambers of the heart quiver instead of contracting in an orderly way. Atrial fibrillation ablation is the procedure of finding and isolating, by catheter, the electrical sources that set that quivering off. Most of those sources lie where the veins from the lungs open into the heart, which is why pulmonary vein isolation is the core of the procedure. The aim is to bring the heart back to a regular beat and to reduce the symptoms.

What Is Atrial Fibrillation?

Normally each heartbeat is started by the heart’s natural pacemaker in the right atrium. The impulse comes at regular intervals, the atria contract, then the ventricles contract.

In atrial fibrillation that order breaks down. Hundreds of irregular impulses a minute come out of the atria. The atria no longer contract; they quiver. Only some of those impulses pass through to the ventricles, and the pulse becomes irregular.

AF is the abbreviation for atrial fibrillation, and it may appear that way in your reports.

What Are the Symptoms?

Palpitations: a sense of irregular, skipping or fast beating in the chest
Tiring easily, finding things hard that used to be comfortable
Breathlessness
Dizziness, greying of vision
A feeling of discomfort in the chest

Some people have no symptoms at all. In them, AF is found by chance on an ECG taken for another reason. Having no symptoms does not mean there is no risk.

Why Does It Matter?

There are two reasons.

The first is the risk of clot. When an atrium does not contract properly, the blood inside it does not empty completely. Blood can pool in the pouch-like appendage of the left atrium in particular, and a clot can form. If that clot breaks free it can travel to the brain and cause a stroke. This is why preventing clot is a heading of its own in the treatment of AF.

The second is strain on the heart. A heart that beats fast and irregularly over a long period can lose pumping strength in time.

What Causes Atrial Fibrillation?

AF does not have a single cause. Anything that wears the atrial tissue or adds to its load prepares the ground.

Age: the strongest factor. It becomes more common as the years go on.
High blood pressure: left uncontrolled over a long period, it raises the pressure on the atrium.
Valve disease: mitral valve problems in particular enlarge the atrium.
Heart failure and coronary artery disease
Thyroid disorders: an overactive thyroid especially. This is a correctable cause, and it is treated first.
Sleep apnoea: repeated pauses in breathing at night put the atrium under direct strain.
Excess weight and diabetes
Alcohol: a single heavy session can set off an episode just as regular heavy use can.
Family history: the risk is higher where close relatives have AF.

Some of these can be changed. That is why they are reviewed when an atrial fibrillation ablation is being planned: where there is a correctable cause, that is dealt with first.

How Is It Diagnosed?

ECG: an ECG recorded during AF establishes the diagnosis.
Holter monitoring: where AF comes in episodes, the ECG in the clinic can be normal. A recording over 24 hours or longer catches the episodes.
Echocardiography: the valves, the size of the chambers and the pumping strength are assessed. An enlarged left atrium affects the plan for the procedure.
Blood tests: thyroid function matters particularly, since a thyroid disorder can cause AF.
Smartwatch recordings: they can raise suspicion but do not establish the diagnosis on their own. Show the recording to your doctor; confirmation comes from an ECG.

What Are the Routes in Treating Atrial Fibrillation?

Treatment runs under three separate headings, and they are not alternatives to one another.

Preventing clot: the decision about a blood thinner follows the risk of stroke. It is made independently of the other two headings.
Rate control: the rhythm stays irregular, but the pulse is kept within a reasonable range with medicines.
Rhythm control: the goal is for the heart to return to its normal rhythm and stay there. Antiarrhythmic medicines, electrical cardioversion and ablation all come under this heading.

Atrial fibrillation ablation is one option under rhythm control.

What Is Atrial Fibrillation Ablation?

Ablation means putting the tissue that causes the rhythm disorder out of action with a catheter. The tissue is not cut or removed; energy takes away its ability to conduct.

Pulmonary Vein Isolation

Most of the irregular impulses that set off AF come from where the veins returning from the lungs open into the left atrium.

The central step of the procedure is to create an unbroken line around those openings. Once the line is complete, impulses from there can no longer reach the atrium. This is called pulmonary vein isolation and it is the core of almost every AF ablation.

Where AF has been going on for a long time, or the atrium is markedly enlarged, work beyond those lines may be needed.

Which Energy Is Used?

There are three methods. All three have the same goal; the difference is the kind of energy.

Radiofrequency (heat): energy delivered from the tip of the catheter treats the tissue point by point to draw a line. It is done under three-dimensional mapping and is flexible, which suits cases where extra lines are needed.
Cryoablation (cold): a balloon-shaped catheter is seated at the mouth of the vein and freezing creates the ring in one go.
PFA (pulsed field ablation): instead of heating or freezing, it uses short pulses of an electrical field. Because it acts selectively on heart muscle cells, it can help protect neighbouring structures such as the oesophagus, nerve tissue and blood vessels.

Which energy is used is decided by weighing the structure of the atrium, how long the AF has been going on and whether an ablation has been done before. More than one method can be used in the same session where needed.

How Is AF Ablation Carried Out?

Beforehand

Before the procedure, the left atrium is checked for clot. This is usually done with an echo from the gullet. If there is a clot, the procedure is postponed and blood-thinning treatment continued.

Your doctor decides how your blood thinner is managed around the procedure; do not stop it on your own.

During the Procedure

The procedure goes in through the vein in the groin. The catheters first reach the right atrium. To get to the left atrium, a controlled crossing is made through the thin wall that separates the two.

A model of the atrium is built with the three-dimensional mapping system, and the points where energy will be delivered are marked on that map. At the end, the isolation is measured to confirm that it is complete.

The procedure is done under deep sedation or a general anaesthetic; staying still is necessary for the lines of isolation to be drawn accurately.

The First Few Days Afterwards

The access site is watched for a period and your rhythm is monitored. There may be bruising in the groin. Most people are back to ordinary life within a few days; heavy activity is increased in stages.

Who Is AF Ablation For?

Patients whose palpitations and symptoms continue despite medication
Those who cannot take antiarrhythmic medicines because of side effects
People whose AF comes in episodes and for whom rhythm control is the goal
Patients whose pumping strength has fallen because of AF
People found to have AF at a young age who do not want to take medicines for many years

When It May Not Be Suitable

Where there is a clot in the left atrium; the procedure is postponed
Where the left atrium is very markedly enlarged
Where there is a correctable cause behind the AF; a thyroid disorder, for instance, is treated first
Where the blood-thinning treatment needed afterwards could not be given
Some patients who have no symptoms and are doing well on rate control

Whether it suits you is decided by weighing your test results and your symptoms together.

When Is the Right Time for Ablation?

“Shall we manage with medicines a while longer?” is a common question in the clinic. Knowing why timing matters makes the decision easier.

AF comes in episodes at first and settles by itself; this is called paroxysmal AF. Over time the episodes lengthen, and then the rhythm stays in AF permanently.

During that transition the atrial tissue changes too. It enlarges and its structure deteriorates. The further that change goes, the harder it becomes to restore a normal rhythm with lines of isolation.

For that reason, atrial fibrillation ablation is generally found to be more worthwhile earlier on in patients for whom rhythm control is the goal. It is not a rule, though: your symptoms, the size of the atrium, your other conditions and your own preference are all weighed together.

In some patients who have no symptoms and are doing well on rate control, ablation may not come into it at all.

The First Three Months: the Blanking Period

This section explains what causes most worry after the procedure, and it is not explained well enough in most places.

Episodes of palpitations can appear in the first three months after an ablation. This is to be expected and does not mean the procedure has failed.

The reason is this: the treated tissue goes through a period of healing, and during it the tissue stays excitable for a while longer. As the lines mature fully, the episodes usually settle.

This stretch of time is known as the blanking period. No judgement is made before the three months are up. If you have an episode, record it and note how long it lasted and what settled it; that information is useful at your review.

Is the Blood Thinner Stopped After an Ablation?

The most important warning on this page is here.

Even where an ablation has succeeded, a blood thinner is not stopped automatically. The decision rests not on the result of the ablation but on your own risk of stroke. Age, blood pressure, diabetes, heart failure and any previous stroke are weighed in a risk assessment.

A blood thinner is continued for at least several months after the procedure. Where the risk is high, treatment may be long-term or permanent.

AF can also come back silently, without any symptoms at all. “I have no palpitations, so it must have gone” is therefore not a safe conclusion. Never stop a blood thinner on your own.

What If It Comes Back?

AF can return once the blanking period is over. That does not mean the treatment has not worked.

The commonest reason is conduction returning in time at one of the isolated areas. A second procedure can be planned; usually the point where it has returned is found and isolated again.

The options depend on the recurrence: carrying on with an antiarrhythmic medicine, a second ablation, or moving to rate control. The decision is made together with your symptoms.

How Much Does the Way You Live Affect the Result?

This is talked about too little, and it affects the outcome of an ablation directly. Ablation quietens the electrical source; it does not change the ground that feeds AF.

Weight: excess weight adds to the load on the atrium. Losing weight can help to reduce the burden of AF.
Sleep apnoea: if there is snoring and daytime sleepiness, it should certainly be looked into. Untreated sleep apnoea is a known factor in AF returning.
Alcohol: even a small amount can set off an episode.
Blood pressure: it needs to be kept under control.
Regular activity: steady and moderate, without overdoing it.

These headings are not decoration around the treatment; they are part of it.

What Are the Possible Risks?

Bruising, bleeding or injury to the vessel at the access site
Fluid collecting in the sac around the heart; rare, and drained if needed
A small opening left in the wall that was crossed; it usually closes by itself
Narrowing at the mouth of a pulmonary vein
Temporary effects on the phrenic nerve; watched for particularly with the balloon methods
Risk of stroke; this is why blood thinners are managed so carefully around the procedure

The risks are weighed against the benefit expected from the procedure and discussed in detail for your own situation at the consultation beforehand.

Atrial Fibrillation Ablation in Antalya

Prof. Dr. Umuttan Doğan is a cardiologist who trained in electrophysiology at the Gülhane Military Medical Academy in 2012; ablation of rhythm disorders under three-dimensional mapping is one of the areas he works in. The procedures are carried out in the catheter laboratory at Antalya American Hospital.

If you have palpitations, or atrial fibrillation has been found on your ECG, you can be seen at the clinic in Konyaaltı with your recordings and results. For the other rhythm disorders see the rhythm disorders and ablation page. You will find his background and contact details on their own pages.

Frequently Asked Questions

My palpitations have carried on since the ablation — has it not worked?

The first three months are called the blanking period, and episodes during it are to be expected. While the treated tissue heals, it stays excitable for a while longer. No judgement is made before the three months are up. It helps to record the episodes and show them to your doctor at your review.

I have had an ablation — can I stop my blood thinner?

Do not stop it on your own. The decision about a blood thinner follows your risk of stroke, not the result of the ablation. AF can also come back silently, with no symptoms. Your doctor decides how long you take it, on the basis of a risk assessment.

Will I be awake during the procedure? Will it hurt?

The procedure is done under deep sedation or a general anaesthetic. You will not feel the catheters moving through the vessels and the heart. Staying still is necessary for the lines of isolation to be drawn accurately.

Can an ablation be repeated?

Yes. The commonest reason is conduction returning in time at one of the isolated areas. At a second procedure that point is found and isolated again. Whether a repeat is needed is decided by weighing your symptoms and your rhythm recordings together.

Which energy will be used for me: radiofrequency, cryo or PFA?

The decision follows the structure of the atrium, how long the AF has been going on and whether an ablation has been done before. All three have the same goal: isolating the pulmonary veins. More than one method can be used in the same session where needed.

The information on this page is for general guidance and does not replace a consultation. Decisions about diagnosis and treatment are made by your doctor after assessing your own situation.