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Catheter Ablation in Combination With Left Atrial Appendage Closure for Atrial Fibrillation
28:13

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Published on: February 26, 2013

Triggered activity and atrial fibrillation

Andrew L Wit1, Penelope A Boyden

  • 1Department of Pharmacology, Columbia University College of Physicians and Surgeons, New York, NY 10032, USA.

Heart Rhythm
|March 6, 2007
PubMed

Insights

Electrical activity in thoracic veins, like the pulmonary veins, can initiate and sustain atrial fibrillation. This review focuses on triggered activity as a potential mechanism driving this condition.

Area of Science:

  • Cardiology
  • Electrophysiology
  • Cardiac Arrhythmias

Background:

  • Atrial fibrillation (AF) is often initiated by electrical impulses originating in thoracic veins.
  • Pulmonary veins, vena cavae, coronary sinus, and ligament of Marshall are implicated in AF initiation and perpetuation.

Purpose of the Study:

  • To review evidence supporting triggered activity as a mechanism for AF initiation and perpetuation in thoracic veins.

Main Methods:

  • Review of in vivo and in vitro studies investigating mechanisms of impulse initiation in thoracic veins.
  • Focus on data related to triggered activity.

Main Results:

  • Multiple thoracic veins contribute to AF initiation and perpetuation.
  • Triggered activity is a proposed mechanism for AF generation in these veins, alongside automaticity and reentry.

Conclusions:

  • Triggered activity is a significant potential mechanism for the initiation and perpetuation of atrial fibrillation originating from thoracic veins.
  • Further research is needed to definitively elucidate the precise mechanisms of impulse initiation in these veins.

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