Heart Ablation for Supraventricular Tachycardia (SVT) Explained

What is heart ablation for SVT?

Heart ablation is a procedure in which a small area of heart tissue is destroyed in order to help correct an arrhythmia. You may also see it referred to as catheter ablation.

The procedure is done by threading thin, flexible tubes called catheters through your blood vessels and into your heart. These catheters can use heat or cold to destroy the target tissue, leaving the surrounding tissues intact.

Radiofrequency energy is often used to generate heat in order to destroy the targeted tissue. This is called radiofrequency ablation. When cold is used, it’s called cryoablation.

What is SVT?

SVT is a type of arrhythmia where the heart can suddenly begin to beat very quickly. It starts in the upper chambers of the heart (atria).

People with SVT have a sudden rapid heartbeat that:

• often feels like fluttering or palpitations
• typically lasts for minutes, but may last for hours
• occurs with variable frequency, such as several times per day or only occasionally
• may be triggered by things like:
  • caffeine
  • alcohol
  • smoking cigarettes
  • physical or emotional stress
• can happen with other symptoms, such as:
  • dizziness or lightheadedness
  • shortness of breath
  • fainting
  • weakness or fatigue
  • chest pain

SVT can affect people of any age. It most commonly begins in childhood or early adulthood.

Many times, SVT can be effectively managed with lifestyle changes or arrhythmia medications. However, heart ablation may be recommended for people that:

• experience long or very frequent episodes of rapid heartbeat
• have found that arrythmia medications weren’t effective at managing their symptoms
• have had unpleasant or undesirable side effects from arrythmia medications

How does heart ablation for SVT work?

Your heart uses electrical signaling in order to coordinate how it beats. This signal is generated by special cells called pacemaker cells, which are located in an area of the heart called the sinoatrial (SA) node.

Normally, electrical signals made by these cells travel through the atria, which causes them to pump blood to the lower chambers of the heart (ventricles).

However, in SVT, some cells in the atria have become abnormal and can generate disorganized electrical signals. This interferes with the regular electrical signals coming from the SA node, leading to a heartbeat that’s too fast.

Cardiac ablation works by specifically targeting and destroying these abnormal cells in the atria. This prevents the disruptive electrical signals and should help to correct SVT while keeping surrounding cells intact.

What to expect during heart ablation

Heart ablation is typically performed in a hospital. The entire procedure takes between 2 and 4 hours to complete.

Local anesthesia is used, so you’ll be awake during the procedure. You’ll also be given a sedative to help you relax. During your heart ablation, the activity of your heart will be monitored using an electrocardiogram (ECG).

Here are the steps of cardiac ablation:

1. The catheters are typically inserted into a blood vessel at the groin, although they can also be inserted at the neck or collarbone. This area is cleaned and numbed prior to catheter insertion.
2. A needle is used to get access to a blood vessel, typically a vein. A small tube called a sheath is placed into the blood vessel.
3. Your doctor will thread a series of catheters through the sheath and into the blood vessels. They’ll then use a screen with X-ray images to help them guide the catheters through your blood vessels and to your heart.
4. The abnormal cells in your heart are located by sending a small electrical signal through electrodes located in some of the catheters.
5. Once the target site has been located, a specialized catheter uses heat or cold to destroy the tissue. This typically only takes about 30 seconds and affects a very small area, leaving the surrounding tissue intact.
6. The catheters are then withdrawn. Pressure is applied to the puncture site to help stop any bleeding and a bandage is placed.
7. You’ll be taken to a room where you can recover and your vital signs can be monitored. If the sheath and catheters were placed at your groin, you’ll need to keep your leg straight for several hours after your procedure.

What are the risks of heart ablation for SVT?

As with any procedure, there are some risks associated with heart ablation. These can include:

• bleeding or bruising
• hematoma
• blood clots
• pseudoaneurysm
• infection
• damage to the heart or blood vessels
• fluid accumulation around the heart
• new arrythmias, potentially necessitating additional treatments or the placement of a pacemaker
• heart attack
• stroke
• a serious allergic reaction to the medications used during the procedure

Complications from heart ablation are quite rare and are estimated to occur in less than 3 percent of people. Most often, they include bleeding or bruising at the puncture site.

How long does it take to recover from heart ablation for SVT?

Most of the time, you can go home from the hospital on the same day as your procedure. You’ll be given specific instructions about what to do at home when you’re discharged.

Generally speaking, you can return to some daily activities in the day or so after your procedure. However, you’ll need to avoid heavy lifting or strenuous activities for a several days.

You’ll be asked to take low-dose aspirin for several weeks after your heart ablation. This is to help reduce the risk of blood clot formation.

Watching for complications

It’s important to stay alert for signs of complications after your procedure. Seek prompt medical care if you notice:

• swelling, pain, or bruising around the puncture site that’s much greater than you’d been told to expect
• bleeding from the puncture site that doesn’t stop when you apply pressure
• signs of infection, such as:
  • fever
  • pus oozing from the puncture site
  • increased redness or swelling at the puncture site
• numbness, coldness, or weakness in any of your extremities
• recurring heart palpitations or other arrhythmia symptoms
• symptoms of a heart attack, such as:
  • chest pain that may spread to your arm, neck, or jaw
  • increased sweating
  • feeling sick to your stomach
  • dizziness or lightheadedness
  • shortness of breath
• signs of a stroke, such as:
  • a sudden, severe headache
  • weakness or paralysis, especially on one side of your body
  • trouble with vision
  • problems with balance or coordination
  • confusion

What’s the outlook for people who’ve had heart ablation for SVT?

Heart ablation can be very effective at treating SVT. Overall, it’s estimated that over 80 percent of people are cured of SVT after having a heart ablation procedure. Recent research generally supports this.

A 2021 study assessed the outcome of 60 people with SVT and pulmonary hypertension that had heart ablation. It found that:

• Following the procedure, normal heart rhythm was restored in 90 percent of the participants.
• Complications occurred in 6.7 percent of individuals.
• After 3 years, 78.3 percent of participants remained free of SVT.

A 2018 study looked into the impact of either heart ablation or arrhythmia medications on quality of life in people with SVT. A survey was used both prior to treatment and 3 months after treatment.

At 3 months, those who had heart ablation reported significant improvements across all survey measures of quality of life. Those taking arrhythmia medications reported both significant improvements and declines in various survey measures.

The takeaway

Heart ablation is a procedure that can be used to treat arrhythmias like SVT. It uses a thin, flexible tube called a catheter to apply heat or cold in order to destroy the tissue that’s causing the arrhythmia.

The heart ablation procedure can take several hours and you’ll typically be able to go home the same day. While there are potential complications associated with the procedure, these happen only rarely.

Overall, heart ablation can be very effective at treating SVT. Consider talking to your doctor about heart ablation if you have SVT episodes that are frequent or long lasting, or don’t respond well to medications.