Achieving Pulmonary Vein Isolation (PVI)

University College London Cardiologist Dr Oliver Segal explains that Catheter Ablation is now usually the preferred option for treating Atrial Fibrillation. The objective of this treatment is to achieve Pulmonary Vein Isolation in order to correctly insulate otherwise abnormal cardiac electrical activity. There are a number of methods to achieve this and Dr Segal says, "Different physicians favour different methods of pulmonary vein isolation and will have different experience using these methods. The key with any medical procedure is that the physician gets reproducible and reliable results with the methods they use with acceptable levels of complication rates."

Endoscopic or Open Heart for PVI

PVI can be performed using fine wires introduced from the top of the leg in a key-hole procedure or surgically, either by endoscope with instruments inserted through small holes in the chest or with open heart surgery by cutting the chest open to expose the heart.

Hybrid Heart Operations

There are also techniques in which surgery and key-hole techniques are combined (known as hybrid operations). Once the heart has been accessed, ablation is performed to destroy the tissue around the entrance to the pulmonary veins.

Type of Ablation Energy

There are different options for ablation energy too, these include:

  • Radiofrequency energy (a bit like microwave energy) to cauterise tissue,
  • Cryo-ablation (when the tissue is frozen to very low temperatures) and
  • Laser (laser energy causes tissue heating just like radiofrequency energy).

Catheters are guided by the use of x-rays, 3-dimensional mapping systems (which create computerised 3D images of the left atrium and show the catheters moving in real-time inside them), direct vision (using an endoscope with the laser baloon catheter) and sometimes ultrasound (echo).

There are claims from the manufacturers of the different ablation technologies of superiority over others but it appears, thus far, overall success rates and complication rates are broadly similar.

See - Treatments for Atrial Fibrillation

The two upper chambers of the heart. Full medical glossary
One of the two upper chambers of the heart. Full medical glossary
Relating to the heart Full medical glossary
A tube used either to drain fluid from the body or to introduce fluid into the body. Full medical glossary
A condition that is linked to, or is a consequence of, another disease or procedure. Full medical glossary
A tube-like viewing instrument that is inserted into a body cavity to investigate or treat disorders. Full medical glossary
Abnormally fast and uneven contractions of the heart muscle, so that blood cannot be pumped efficiently Full medical glossary
A large abdominal organ that has many important roles including the production of bile and clotting factors, detoxification, and the metabolism of proteins, carbohydrates and fats. Full medical glossary
per vaginam Full medical glossary
A group of cells with a similar structure and a specialised function. Full medical glossary
A diagnostic method in which very high frequency sound waves are passed into the body and the reflective echoes analysed to build a picture of the internal organs – or of the foetus in the uterus. Full medical glossary
A blood vessel that carries blood towards the heart. Full medical glossary