Pulmonary vein isolation (PVI)

This procedure is a treatment for atrial fibrillation (AF). AF can lead to symptoms of breathlessness, palpitations, dizzy turns, fatigue and in severe cases can weaken the heart muscle.

People with AF have a higher risk of stroke because blood can stagnate in pockets of the atria instead of being pumped through normally, and form blood clots which can cause a stroke.

The goals of treatment for AF include regaining a normal heart rhythm (sinus rhythm), controlling the heart rate, reducing symptoms, and reducing the risk of blood clots and stroke. 

Should the first PVI ablation not be successful long term and AF returns it may be possible to repeat the procedure.

What is radio-frequency ablation?

Radiofrequency ablation (RFA) is performed using specialised catheters which deliver radio-frequency energy from the tip of an electrode. This energy changes the heart tissue it is in contact with, although technically it does not burn the heart, the lesion created is often referred to as a burn.

A ring of small 2-3mm burns is made around each vein until it is isolated. It is also possible to burn straight lines, or target other sites of ectopic beats.

RFA is often used for people:

  • with larger atria
  • who have been in AF for a long time, or
  • require a second procedure with more extensive ablation.

RFA PVI usually takes 2-4 hours to perform.

What is cryoablation?

Cryoablation utilises a catheter with a 28 mm balloon at the end to cool and freeze a ring of heart tissue.

This balloon is inflated at the entrance to each pulmonary vein. It is inflated with pressurized refrigerant liquid (nitrous oxide or N2O). As this gas vaporizes inside the balloon, it absorbs heat from the surrounding tissue, thereby cooling and freezing a ring of heart tissue. Each freeze is 3 to 4 minutes long.

Cryoablation is used for people:

  • with smaller atria who have not been in AF very long, or
  • have intermittent AF

It is usually a shorter procedure than an RFA PVI. Cryo PVI typically takes 1.5 - 2 hours. 

How should I prepare for my procedure?

Intra will provide you with information about preparing for a pulmonary vein isolation (PVI) procedure.

What will I experience during the procedure?

While you are anaesthetised, the doctor places a small tube called a sheath in the femoral vein near the top of the leg. The ablation catheter (RFA or Cryo balloon) is threaded up to the heart via this sheath.

The catheter is positioned in the left atrium, by making a tiny hole in the septum between right and left atria (transseptal puncture), which closes naturally after the procedure.

In many patients, a 3D electro-anatomical map is made of the left atrium, to help guide the catheters to exact locations. The ablation catheter is then moved to the entrance of each pulmonary vein so the ablation can be performed. At the end of the procedure, the catheters and sheathes are removed and pressure applied to the vein to stop the bleeding. 

What happens after my procedure?

After the PVI procedure, you may feel discomfort in the throat where the breathing tube was placed, and in the groin area where the sheath was inserted.

Once you are awake and bleeding has stopped, you will be taken to Recovery or the ward for observations to ensure you recover as expected. You will be required to lie flat for several hours.

This is an overnight stay procedure. It is important transport arrangements are made when leaving the hospital as it is recommended you do not drive a car for 48 hours after the procedure.

When can I resume travel and other activities?

It is advisable not to drive a car for 48 hours, or a bus or truck for up to six weeks. Someone must drive you home following the procedure.

Travel by air is not recommended domestically for 48 hours, short international flights for 2 weeks, or long-haul international for 6 weeks after a PVI.

You can return to work within a week unless your job requires heavy lifting. Light exercise may begin after 1 week.
 

What are the risks?

Your doctor will discuss the risks with you before the PVI procedure. There is a very small risk of death or stroke. These risks are very rare:

  • Requiring a drain or surgery to repair damage to a blood vessel or heart wall or lung.
  • Damage to the oesophagus found some weeks after the procedure.
  • Blood clots to the lungs, brain (causing a stroke) or lower legs.
  • Allergy to the contrast (dye), or aneasthetic medications. 
  • Bruising and bleeding at the groin, being the catheter entry point, is common following the procedure.