Catheter Ablation for Ventricular Fibrillation

Catheter Ablation for Ventricular Fibrillation

Thejus et al has written an editorial on catheter ablation for prevention of recurrent ventricular fibrillation in the current issue of Indian Pacing and Electrophysiology Journal [1].  The current recommendation for treatment of recurrent ventricular fibrillation is the implantation of an ICD (Implantable Cardioverter Defibrillator). ICDs are costly and have a finite battery life, requiring replacement when the end of battery life is reached. The tolerance of ICD shocks are also not very good among patients, often leading to psychological problems due to fear of an impending shock. To overcome this problem, Haissaguerre et al pioneered the radiofrequency ablation of ventricular fibrillation and it has been taken up by several other investigators. Ventricular fibrillation is triggered by an ectopic impulse falling in the vulnerable period of the ventricular repolarization and is maintained by multiple wavelets of reentry. Radiofrequency catheter ablation aims at controlling this trigger. Most of the cases of ventricular fibrillation are precipitated by ventricular premature complexes arising from the Purkinje system. Origin of the ventricular ectopic beat from the Purkinje system is identified by a Purkinje potential occurring just before the ectopic beat. It is a sharp spike of less than 10 msec in duration. Radiofrequency catheter ablation at this site causes the cessation of ventricular ectopic beats which trigger the ventricular fibrillation. The recurrence rate after successful ablation was only 9% over a mean follow up period of 22 months in cases of idiopathic ventricular fibrillation.
In another article in the same issue of the journal, Thoppil et al describe the successful treatment of post myocardial infarction electrical storm by targeting the Purkinje potentials [2].

References

  1. Thejus J, Francis J, Haissaguerre M. Radiofrequency ablation in ventricular fibrillation. Indian Pacing Electrophysiol J. 2008; 8:238-241,
  2. Thoppil PS, Rao BH, Jaishankar S, Narasimhan C. Successful catheter ablation of persistent electrical storm late post myocardial infarction by targeting purkinje arborization triggers. Indian Pacing Electrophysiol J. 2008; 8: 298-303.