Ventricular Ectopics or Normal Heart Ventricular Tachycardia (VT)
What are Ventricular Ectopics or Normal Heart VT?
Ventricular Ectopics occur when a cluster of cells within the lower chambers of your heart (ventricle) gives rise to the electrical impulse instead of the natural pacemaker of your heart (the sinus node). In some people, these can occur while exercising but in others they can occur while sleeping or when relaxing.
Ectopic beats are very common and in most people with no other heart disease, they are harmless. However, they can be troublesome due to the sensation they sometimes produce. Most people who have ectopics are completely unaware of them. Some patients feel palpitations which can be unpleasant but will not damage your heart unless extremely frequent.
A sequence of these ectopics can result in what is called ventricular tachycardia (VT). The controlled contraction of the ventricles is important for the heart to pump blood around your body and brain and to maintain a good blood pressure. VT can impair the ability of the heart to supply blood and may result in palpitations, dizziness and blackouts.
VT commonly happens in patients with weakened hearts (heart failure) but as with Ventricular Ectopics, VT can also occur in people with normal hearts. This is called Idiopathic Ventricular Tachycardia, also described as Focal Ventricular Tachycardia (see video below), which accounts for about 10% of all VTs. The commonest location for the source of Ventricular Ectopics or Idiopathic VT in the heart is the Right Ventricular Outflow Tract (RVOT).
Ventricular Tachycardia from Khan Academy.
Ventricular Ectopics may be seen on an electrocardiogram (ECG) but in patients with infrequent symptoms, a 24 hour Holter monitor may be undertaken to clarify the pattern and frequency of the ectopic beats. Some patients may also be investigated with an exercise treadmill test to quantify the burden of ectopics on exercise.
What are the treatment options for Ventricular Ectopics or Idiopathic VT?
No treatment. If your ectopics are occurring very infrequently, you may simply chose to live with it.
Medications. Tablet treatments can be effective in around 25-50% patients. Medications suppress the ectopics but do not cure this condition. The aim of medications is to reduce the frequency and severity of your symptoms. All medications come with side effects and your doctor will discuss these with you.
Radiofrequency ablation. This is a procedure performed by an Electrophysiologist and is very effective to cure Ventricular Ectopics or VT in normal hearts. The next sections will explain this procedure in detail.
How do I prepare for Ventricular Ectopic or Idiopathic VT ablation?
Please refer to the section on EPS. This procedure is usually performed under conscious sedation and local anaesthetic. General anaesthesia is not commonly used as it suppresses the ectopics preventing your Electrophysiologist from finding the source of your ectopics.
How is Radiofrequency Ablation performed for Ventricular Ectopics or Idiopathic VT?
Please refer to the section on EPS on how EPS is performed. Catheters will be placed in your heart to identify and localise the abnormal tissue. Most Electrophysiologist routinely use a 3-dimensional navigational system which works like GPS navigation to guide the ablation procedure. This will help navigate the catheter inside your heart and minimise the need for X-rays. The 3-dimensional mapping also helps to localise the source of ectopics or VT. You may be given some intravenous medications to stimulate the ectopics or VT.
When the source of ectopics or VT is identified, radiofrequency ablation will be applied to this spot. If the source is near to your aorta, a coronary angiogram will be performed before ablation to ensure the coronary arteries are not in close proximity or at risk of damage.
The entire procedure may take 2-3 hours.
What is the success rate for ablation of Ventricular Ectopics or Idiopathic VT?
This procedure carries an approximately 90% chance of curing your Ventricular Ectopics or VT. There is a 5-10% chance of Ventricular Ectopics or VT recurring after an apparently successful procedure.
It is important that your Ventricular Ectopic or VT is present on the day of the procedure as this will influence the success of the procedure.
What are the risks of Ventricular Ectopic or Idiopathic VT ablation?
Ablation for Ventricular Ectopics or VT is commonly performed and safe. The worldwide complication rate for ablation procedures is less than 2%. Although most patients who undergo this type of ablation do not experience any complications, you should be aware of the following risks:
- Blood vessel problems: bleeding, bruising, damage to the vessel wall, abnormal connections and blood clots can form in the blood vessel in your groin or higher up near the heart. Usually these settle by themselves, but sometimes medications, injections or small operations are required to fix them.
- Abnormal heart rhythms: these are deliberately provoked during the procedure, but can become unstable requiring an electric “shock” to restore a normal heart rhythm. There is a very small risk of requiring a pacemaker if the normal and necessary electrical system of the heart is damaged.
- Perforation: there is a very small chance of causing a leak of blood around your heart. This usually settles without treatment but can also be dealt with by inserting a drain from the chest wall.
- Life-threatening complications like stroke or heart attack are exceedingly rare (less than 0.1%). There is no risk of these problems if the ablation takes place entirely on the right side of the heart.
What happens after Ventricular Ectopics or Idiopathic VT ablation?
You will be required to lie flat for 2-4 hours. You may have a compression clamp over your groin area during this time. Your nurse will check on you to see if there is bleeding or swelling at the groin site. Most people can start eating and drinking water within 4-6 hours after the procedure. Most patients stay in the hospital overnight and their heart rhythm may be monitored. Your Electrophysiologist may stop, switch or commence you on new medications after the procedure.
You should avoid strenuous physical activity and sports for 2 weeks after the procedure. Most people take approximately 1 week off work. Some patients may experience minor chest discomfort and brief palpitations several days after the procedure. This may be due to the irritation caused by the ablation and will usually settle. If this persists, please consult your Electrophysiologist. You should not drive for at least 48 hours although we usually recommend that you do not drive for a week.
Your groin site might be sore for several days. A small bruise at the groin site is normal but if it starts to bleed, you can contact your local doctor or the Electrophysiologist.