It is done after a comprehensive electrophysiolgic study . Today these procedures are performed in the electrophysiology laboratory where small tubes called catheters are placed into the veins and arteries in the legs, and sometimes arm or neck and passed to the heart.
Most catheter ablations utilize radiofrequency energy to heat the tip of a special catheter.
The procedure is done with the patient lying on their back and in general with the patient in a sleep like sedated state. The key to performing catheter ablation is mapping of the cardiac arrhythmia. This allows the electrophysiologist to determine where in the heart the arrhythmia arises and allows for placement of the ablation catheter at that location. The EPS procedure is often done just before the ablation procedure at the same sitting. This allows most patients to have their arrhythmia diagnosed and treated with one procedure.