30/05/2026
〽️Electrical conduction system of the heart
1. Sinoatrial (SA) Node: This structure, widely recognized as the heart's intrinsic pacemaker, generates the initial electrical impulse that sets the rhythm of cardiac contraction.
2. Bachmann's Bundle (Interatrial Tract): This specialized pathway conducts the impulse rapidly from the right atrium to the left atrium, ensuring synchronous atrial contraction.
3. Anterior Internodal Tract: Traditionally described as one of the three preferential conduits transmitting the impulse from the SA node to the AV node.
4. Middle Internodal Tract (Wenckebach's pathway): The second proposed internodal pathway, believed to facilitate conduction within the right atrium.
5. Posterior Internodal Tract (Thorel's pathway): The third internodal tract, thought to participate in conducting impulses toward the AV node.
6. Atrioventricular (AV) Node: Serving as a critical electrical gateway, it imposes a deliberate delay on conduction to allow for optimal ventricular filling before contraction.
7. Bundle of His (Atrioventricular Bundle): This is the only electrical bridge transmitting impulses from the atria through the fibrous cardiac skeleton into the ventricles.
8. Right Bundle Branch: Conveys the depolarization wave rapidly to the right ventricular myocardium.
9. Left Bundle Branch: Delivers impulses to the left ventricle, dividing further into fascicles to coordinate activation.
10. Left Anterior Fascicle: A subdivision of the left bundle branch, targeting the anterosuperior portion of the left ventricle.
11. Left Posterior Fascicle: Another subdivision of the left bundle branch, directing conduction toward the posteroinferior segments of the left ventricle.
12. Purkinje Fibers: Constituting the terminal network of specialized conduction fibers, they ensure rapid, coordinated ventricular depolarization culminating in efficient contraction.
