In theheart'sconduction system,Bachmann's bundle(also called theBachmann bundleor theinteratrial band)[1]is a branch of the anterior internodal tract that resides on the inner wall of theleft atrium.It is a broad band ofcardiac musclethat passes from theright atrium,between thesuperior vena cavaand theascending aorta.[2]Bachmann's bundle is, during normalsinus rhythm,the preferential path for electrical activation of the left atrium. It is therefore considered to be part of the "atrial conduction system" of the heart.
| Bachmann's bundle | |
|---|---|
 Image showing Bachmann's bundle | |
| Anatomical terminology |
History
editIn 1916,Jean George Bachmannconducted canine experiments. He found that clamping the muscular bundle of fibers that connects the atria caused a significant conduction delay.[3]
Structure
editBachmann's bundle receives its blood supply from thesinoatrial nodal artery(right, left or both).[4]
Besides Bachmann's bundle, the other three conduction tracts that constitute theatrial conduction systemare known as theanterior,middle, andposteriortracts, which run from the sinoatrial node to theatrioventricular node,converging in the region near thecoronary sinus.Atrial automaticity fociare within the atrial conduction system. The concentration of converging conduction tracts near the coronary sinus results in considerable automaticity activity originating in that area.
Function
editThe normal cardiac rhythm originates in thesinoatrial node,which is located in the right atrium near the superior vena cava. From there, the electrical activation spreads throughout the right atrium. There are at least four locations where the activation can pass to the left atrium. Apart from Bachmann's bundle these are the anteriorinteratrial septum,posterior interatrial septum, and thecoronary sinus.[5]Because it originates close to the sinoatrial node and consists of long parallel fibers, Bachmann's bundle is, duringsinus rhythm,the first of these connections to activate the left atrium.
See also
editReferences
edit- ^"19.2 Cardiac Muscle and Electrical Activity - Anatomy and Physiology | OpenStax".openstax.org.Retrieved28 August2022.
- ^James, Thomas N. (1 October 1963). "The connecting pathways between the sinus node and A-V node and between the right and the left atrium in the human heart".American Heart Journal.66(4): 498–508.doi:10.1016/0002-8703(63)90382-X.
- ^Khaja, Azamuddin; Flaker, Greg (August 2005). "Bachmann's Bundle: Does It Play a Role in Atrial Fibrillation?".Pacing and Clinical Electrophysiology.28(8): 855–863.doi:10.1111/j.1540-8159.2005.00168.x.PMID16105015.
- ^van Campenhout, M. J. H.; Yaksh, A.; Kik, C.; de Jaegere, P. P.; Ho, S. Y.;Allessie, M. A.;de Groot, N. M. S. (15 October 2013)."Bachmann's Bundle: A Key Player in the Development of Atrial Fibrillation?".Circulation: Arrhythmia and Electrophysiology.6(5): 1041–1046.doi:10.1161/CIRCEP.113.000758.
- ^Sakamoto, S-I; et al. (2005). "Interatrial Electrical Connections: The Precise Location and Preferential Conduction".Journal of Cardiovascular Electrophysiology.16:1077–1086.doi:10.1111/j.1540-8167.2005.40659.x.