Bachmanns bundle

These specialised conduction cells are distributed throughout the heart forming specialised conduction pathways (Fig. 1.5). Depolarisation occurs in the Sinoatrial node (SAN). This is a collection of self-excitory (pacemaker) cells that normally fire at a rate of between 60 and 100 Beats Per Minute (BPM). The wave of Depolarisation moves from the SAN through an intra-atrial tract called Bachmanns bundle into the left atrium and to the Atrioventricular (AV) node. From here the impulse travels down the bundle of His into the right and Left bundle branches and finally into the Purkinje fibres activating the ventricles. 

Some authors argue about the existence of the intemodal pathways and/or the Bachmanns bundle and instead believe that impulses generated in the SAN are transmitted through normal cardiac tissue in waves. The analogy of a stone dropped into water creating electrical ripples that eventually reach the AV node is often sighted. 

Following initiation of the electrical impulse from the SA node, the impulse travels through the internodal pathways of the specialized atrial conduction system and Bachmann s bundle (Fig. 6-1 j.1 The atrial conducting fibers do not traverse the entire breadth of the left and right atria, as impulse conduction occurs across the internodal pathways, and when the impulse reaches the end of Bachmann s bundle, atrial depolarization spreads as a wave similar to that which occurs upon throwing a... 

Khaja A, Elaker G. Bachmann s Bundle does it play a role in atrial fibrillation Pacing Cfin Electrophysiol 2005 28 855-63. 

Bailin SJ. Is Bachmann s Bundle the only right site for single-site pacing to prevent atrial fibrillation Results of a multicenter randomized trial. Card Electrophysiol Rev 2003 7 325-8. 

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