AF Ablation in Kent and London
Catheter ablation of atrial fibrillation is a surgical procedure used with medicines and lifestyle changes to reduce the amount of symptoms that patients get from this troubling arrhythmia. Different methods are used and there are some important differences, but all involve feeding thin flexible tubes called catheters into a blood vessel to disrupt abnormal electrical signal. The procedure aims to improve quality of life and reduce symptoms.
You can read more below about the procedure as carried out by Dr Idris Harding
for patients in Kent and London.
What is an AF ablation? - When to see a cardiologist - Reasons for AF ablation - Getting ready - On the day - Recovery - Complications - FAQs
What is an AF Ablation?
Patients with atrial fibrillation are usually offered treatment of the underlying cause, treatments to control blood pressure, diabetes, thyroid disorders and other associated heart disease, treatments to lower the risk of stroke, and treatments to control symptoms. AF ablation is one treatment that can control symptoms.
You can read more about atrial fibrillation here.
AF ablation is a surgical technique accessing the heart from punctures at the top of one or both leg veins, to create scar tissue and kill off small areas of heart muscle that tend to trigger atrial fibrillation. Originally, this was done via surgical ablation, requiring open heart surgery, but modern techniques allow scar tissue to be formed using thin flexible tubes called catheters fed up to the heart from the leg.
Many different patterns of scar creation have been trialed to treat atrial fibrillation. Isolation of the pulmonary veins by creating scar tissue around them seems the most effective way to prevent AF. Different methods of creating scar exist, with two methods (radiofrequency and cryotherapy) in common use in the UK currently with a third (pulsed field ablation - PFA) just becoming established.
It is important to understand that, unlike treatments for other heart rhythm problems, AF surgery is unlikely to work on its own as a total cure for atrial fibrillation. AF attacks should reduce dramatically, and some patients will experience years without an attack after the procedures. More than one procedure may be needed to get maximum benefit, along with lifestyle changes and medications as well. There is a strong possibility that even after excellent benefit to start with, symptoms may return months or years later.
When to See a Cardiologist
Symptoms such as palpitations, a racing heart beat, episodes of sudden breathlessness, and chest tightness may be suggestive of an intermittent heart rhythm problem such as atrial fibrillation.
A cardiologist - in particular a cardiac electrophysiologist (heart rhythm specialist) - has access to a range of blood tests and heart tests to confirm the diagnosis.
Following tests, a doctor may suggest a program of treatment to control AF and deal with the underlying causes such as being overweight, high blood pressure, or obstructive sleep apnoea. Most treatments for AF are more successful the earlier they are used, so consulting a specialist early is vital. It is important that other heart disease such as blood pressure, diabetes, insulin resistance and thyroid disease is diagnosed and treated to slow the progression of arrhythmia.
Some patients will experience AF only intermittently. Ablation is most successful in patients with only intermittent AF.
If AF is continuous, however, it is likely that the disease is more established and a pulmonary vein isolation operation may be less successful in this setting. In this situation a specialist may recommend a “trial” of normal rhythm using a cardioversion before deciding whether ablation is worthwhile.
Reasons for AF Ablation
AF surgery may be recommended for any of the following reasons. Sometimes more than one reason applies:
To reduce episodes of atrial fibrillation symptoms
Patients with intermittent (“paroxysmal”) atrial fibrillation stand the best chance of benefitting from the procedure. Pulmonary vein isolation stands a very good chance of reducing the time they spend in the abnormal rhythm and reducing AF symptoms.To prevent symptoms of persistent AF
Patients with continuous (“persistent”) atrial fibrillation may experience symptoms of palpitations, breathlessness, dizziness and chest pain more-or-less constantly. A normal heart rhythm can be restored with a cardioversion procedure. Some patients may be offered an ablation to reduce the chance of persistent AF coming back again after a cardioversion.To reduce the complications of persistent AF
Some trials have shown that patients with persistent atrial fibrillation and heart failure have a reduced chance of death and hospitalization after an AF ablation. This may be another reason why the procedure is suggested to patients with AF and a weak heart muscle.
Getting Ready
Getting ready for AF ablation procedure is similar to preparing for any operation. Overweight patients may be advised to reduce their weight gradually prior to the procedure to minimise risk of complications and also to increase the chance of freedom from AF after the procedure.
It may be useful to plan for a period of rest and recuperation after the procedure. Most patients will be very well after discharge from hospital but a short period of feeling “fluey” and tired is quite common. Occasionally some arrhythmias are worsened for a short time after an ablation procedure and planning how you would cope with this is quite important. It may not be realistic, for example, to return to a busy work schedule immediately after the surgery. Planning for some time off may be sensible.
Transport on the day of the procedure is also a consideration. Patients in the UK are not permitted to drive for 48hrs after the operation. Most hospitals will want patients to be accompanied immediately after discharge and for the coming days, just in case a problem occurs.
On The Day
AF ablation may be carried out under general anaesthetic or under sedation, depending on whether radiofrequency, cryoablation or PFA is used. Other minor differences, particularly in the risks of specific complications, exist between the different surgical methods. All methods currently in use in the UK have similar success rates. The absolute chance of success depends on a number of factors including how long the AF has been present, whether it is intermittent (“paroxysmal”) or continuous (“persistent”) and whether the patient has other medical conditions that impact the chance of the AF returning.
A first time operation using radiofrequency ablation can take 2hrs or so. Using cryoablation or PFA tends to be quicker. Patients need to lie flat for the procedure time and a couple of hours afterward to reduce risk of bleeding.
Patients who opt for the procedure under local anaesthetic will inevitably feel some parts of the ablation procedure, and the sensations depend on which method is used. For example cryoablations give a feeling similar to an intense “ice cream headache” during the freezing treatments, which last up to four minutes each. Radiofrequency is generally felt more as discomfort in the chest.
During some AF procedures there is a risk of damage to the nerve supplying the diaphragm and so this nerve is tested frequently throughout some parts of the procedure: this feels like having violent hiccoughs once per second for four minute bursts.
Access is gained to one or more veins at the top of the leg and this is used to feed wires up to the heart to complete the operation. At the end of the procedure the wires are removed, and a stitch applied at the top of the leg to prevent bleeding.
Recovery
Recovering from an AF ablation is variable. Some patients get very few after-effects, however others can get a short flu-like illness and chest pains. Some patients experience an increase in AF symptoms though this is usually temporary.
Rarely, persistent AF can start soon after an AF ablation and require a cardioversion to correct it. This is unusual, and does not necessarily predict that the procedure has failed. It is perfectly possible to have a lot of AF immediately after the surgery which then resolves and remains absent for years afterwards.
The main restrictions on activity after an AF procedure relate to the puncture wounds into the femoral vein. To minimise the risk of bleeding patients are advised to avoid running, squatting, swimming and heavy lifting for two weeks after the procedure.
The DVLA also stipulate a driving ban after all EP procedures. The length of the ban depends on the licence held. For example, group 1 (car and motorbike) drivers are currently subject to a two day ban.
Complications
AF ablation does carry some significant potential complications. Around one in 100 patients will experience significant problems from the puncture wounds at the top of the leg and in extreme cases this may need surgery though the rate of this is much lower (around one in 1000). Some pain following the procedure, in the chest or around the puncture site in the leg, is common but usually mild.
Bleeding around the heart is also possible. Around one in 200 patients will need a pacemaker after an AF ablation and one in 500 will suffer a stroke. The risk of a fatal complication from an AF ablation is between one in 700 and one in 1000. The individualised risks of these complications may be higher or lower depending on the medical background of the patient and in particular patients with obesity are at higher risk of complications, and those complications being difficult to fix.
FAQs on AF Ablation
What sorts of AF ablation are there?
There are two major sorts of atrial fibrillation ablation surgery:
One-shot
Point-by-point
One-shot techniques target an area of tissue around the pulmonary veins using surgical tools designed only for this task. This technique is fast and effective, as long as the AF is coming from the veins. If AF is not coming from the veins, this technique does not work. Most first time AF ablation is now performed using a one-shot technique as this is an efficient way to treat the majority of AF. Different one-shot technologies are available:
Cryoablation - uses very low temperatures to kill cardiac cells
Pulsed field (PFA) - uses pulses of electricity to kill only a certain type of cardiac cells
Laser - uses laser energy to kill cardiac cells
Radiofrequency (RFA) - uses a vibrating electric current to kill cardiac cells
The point-by-point AF technique uses more versatile instruments to create a bespoke pattern of ablation within the heart, targeted to where the doctor feels the AF is coming from. Redo AF ablation is performed using point-by-point. Unlike one-shot techniques, point-by-point procedures always uses radiofrequency energy.
The choice of technology may influence whether an ablation is carried out under general anaesthetic or under local anaesthetic with sedation. For example, point-by-point procedures usually take longer than one-shot, so are more likely to be offered under general anaesthetic, for patient comfort.
How successful is AF ablation?
The success of ablation depends on the type of AF, and in particular the duration of the abnormal heart rhythms.
For paroxysmal AF, (that comes and goes in short attacks) a first-time atrial fibrillation ablation using one of the established one-shot techniques stands an 80-90% chance of giving patients a significant reduction - or complete freedom from - atrial fibrillation for up to a few years. The success rate improves (and may last longer) if other interventions such as weight loss and treatment of other contributing medical conditions are used alongside ablation.
For persistent AF (that causes constant irregular heartbeat before the ablation) a first-time ablation achieves freedom from symptoms in 50% of patients, i.e. much lower than for paroxysmal AF. Repeat ablations are more common for persistent atrial fibrillation, as the abnormal electrical activity targeted by the ablation tends to return more often. Patients with atrial fibrillation caused by previous heart surgery may experience lower success rates.
How many times can you have heart ablation?
Cardiac ablations may be repeated if a first attempt is not successful. Failure rates are different depending on which heart rhythm problem is being treated. Roughly 1 in 5 patients undergoing a first atrial fibrillation ablation will not get maximum benefit and will be considered for a second attempt. Third, or more, attempts are possible but are less common.
What is the recovery time for AF ablation?
Most patients will be home from hospital the same day or day after the procedure. Recovery from cardiac ablation is mainly about healing of the punctures into the vein at the top of the leg. It takes around a week for the punctures to heal though some discomfort may last longer and in some medical conditions the healing can be delayed. Discomfort in the chest is common in the early stages after discharge home, sometimes accompanied by flu-like symptoms. Some patients experience temporarily worse arrhythmia symptoms for up to a couple of weeks. Even though this is uncommon it is best to plan for it and to avoid strenuous work or travel in the period immediately after the procedure.
What are the alternatives to catheter ablation?
Other treatments for arrhythmia include cardioversion, antiarrhythmic medications, lifestyle changes, treating other heart problems that may have triggered AF, or simply accepting that an arrhythmia is permanent.
Some patients get excellent symptom control using a combination of a pacemaker to prevent very slow heart rates and high doses of anti-arrhythmic drugs to prevent fast heart rates. This “pace and block” strategy is common in more elderly patients and in people who do not like the sound of the risks involved in ablation procedures. After a pacemaker is implanted a more limited ablation called of the AV node alone is also an option. This is sometimes referred to as “pace and ablate”. This has a more certain outcome than attempting a return to a normal rhythm but has other down sides.