Related terms: cardiac ablation, radiofrequency ablation
Any irregularity in your heart's natural rhythm is called an arrhythmia. Almost everyone's heart skips beats, and these mild palpitations are usually harmless. But there are about 4 million Americans who have recurrent arrhythmias, and these people usually need treatment for their condition.
Electrical impulses from the heart muscle cause your heart to beat (contract). This electrical signal begins in the sinoatrial (SA) node, located at the top of the heart's upper-right chamber (the right atrium). The SA node is sometimes called the heart's "natural pacemaker."
When an electrical impulse is released from the SA node, it causes the upper chambers of the heart (the atria) to contract. The signal then passes through the atrioventricular (AV) node. The AV node checks the signal and sends it through the muscle fibers of the lower chambers (the ventricles), causing them to contract.
The SA node sends electrical impulses at a certain rate, but your heart rate may still be altered by physical demands, stress, or other factors. Sometimes, the SA node does not work properly, causing the heart to beat too fast, too slow, or irregularly. In other cases, the heart's electrical pathways are blocked, which can also cause an irregular heart rhythm.
can be divided into two categories: ventricular and supraventricular. Ventricular
arrhythmias happen in the heart's two lower chambers, called the ventricles.
Supraventricular arrhythmias happen in the structures above the ventricles,
mainly the atria, which are the heart's two upper chambers.
Arrhythmias are further defined by the speed of the heartbeats. A very slow heart rate, called bradycardia, means the heart rate is less than 60 beats per minute. Tachycardia is a very fast heart rate, meaning the heart beats faster than 100 beats per minute. Fibrillation, the most serious form of arrhythmia, results in uncoordinated contractions of individual heart-muscle fibers.
What is catheter ablation?
ablation is a procedure where energy delivered through a catheter tip is used
to treat various arrhythmias. Several different forms of energy can be used for
this purpose, but the most common type is radiofrequency energy. Radiofrequency
energy is a type of energy that uses radio waves to produce heat that destroys
the tiny area of heart tissue that is causing your arrhythmia. When the tissue
is destroyed, it restores your heart's regular rhythm. This procedure is also
called radiofrequency ablation.
people with arrhythmias, medicines work quite well to control the abnormal
heart rhythm. But when medicines don't work, doctors may suggest catheter
ablation is used to treat a wide variety of cardiac arrhythmias. Some of them
which is a rapid, regular heart rate where the heart beats anywhere from
150-250 times per minute in the atria. Another name for SVT is paroxysmal
supraventricular tachycardia (PSVT). The word "paroxysmal" means occasionally
or from time to time.
- Atrial flutter, which happens when the atria beat
very fast, causing the ventricles to beat inefficiently as well.
- Atrial fibrillation, which is a fast, irregular and chaotic rhythm
involving the atrial chambers. It
results in loss of pumping contribution by the atria and rapid irregular beating
of ventricles. It is a main cause of stroke, especially among elderly
- Ventricular tachycardia, which is
rapid heartbeat arising from the lower chambers of the heart.
What can I expect during catheter ablation?
procedure is performed in the cardiac catheterization angiography suite (also
called the cath lab) or the electrophysiology lab. You may not eat or drink
anything after midnight the night before the procedure. If you have diabetes,
you should talk to your doctor about your food and insulin intake, because not
eating can affect your blood sugar levels.
to your doctor about any medicines that you are taking because he or she may
want you to stop taking them or change the dosage before the procedure. It may
be helpful to make a list of your medicines and bring it with you to your final
doctor's appointment before the procedure, so that the doctors know exactly
what you are taking and how much. This is especially important if you are
medicines or antiplatelet medicines. You should try to take your
medicines with small sips of water.
you are in the cath lab, you will see television monitors, heart monitors, and
blood pressure machines. You will lie on an examination table, which is usually
near an x-ray camera. Small metal disks called electrodes will be placed on
your chest. These electrodes have wires called leads, which hook up to an electrocardiogram
machine. This machine will monitor your heart rhythm during the procedure. To
prevent infection, you will be shaved and cleansed around the area where the
catheter will be inserted.
very small needle will be put in the vein of your forearm. This is called an
intravenous line or IV. The IV will be used to give you a medicine to relax
you, and you may even fall asleep. Otherwise, you will be awake for the
will be given an anesthetic medicine to numb the area around where the catheter
will be inserted. This needle may hurt a bit, much like at the dentist after
being given Novocain. You should not feel pain during any part of the
procedure, but if you do, ask the doctors for more medicine.
gaining entrance into a blood vessel in
your groin, arm, or neck, doctors insert several long, thin tubes with wires,
called electrode catheters, through a sheath and feed these tubes into your
heart. They use a video monitor (like a TV screen) to see the process. You will
not feel the catheter passing through the blood vessel because it lacks nerve endings on the inside lining.
To locate the abnormal tissue causing arrhythmia, doctors
send a small electrical impulse through the electrode catheter to activate your
arrhythmia. Other catheters are used to record the heart's electrical signals
and locate the abnormal tissue. Doctors will then place a catheter at the exact
site of the abnormal cells in your heart. The radiofrequency energy is sent
through this catheter to cauterize the
tissue causing your arrhythmia. You may feel a mild burning sensation when the
radiofrequency energy is applied to the heart tissue.
the catheter is removed, firm pressure will be applied to the site in your groin
to stop any bleeding. You will also be bandaged. To avoid bleeding at the
catheter insertion site, you will need to lie very still for several hours,
either in the recovery area or in your hospital room.
usually takes 2 to 4 hours. If you have several areas of abnormal tissue, then
the procedure may take longer. Depending on how you are feeling after the
procedure, you may either go home the same day or you may have to stay
overnight in the hospital.
What happens after the procedure?
you leave the hospital, your doctor will give you specific instructions about
drinking plenty of fluids, driving, and bathing. Most people can return to
their normal activities the day after they leave the hospital. You should avoid
heavy physical activity for 2-3 days. Ask your doctor when you can return to
You may feel fatigue
or chest discomfort for about 2 days after the procedure. You should tell your
doctor if this lasts longer than 2 days or the pain is severe. You may also
experience palpitations after the procedure. These abnormal heartbeats will go
away as your heart heals after the procedure.
See also on this site:
See on other sites:
National Heart, Lung, Blood Institute
What is Catheter Ablation?
Updated December 2013