The AV node features as a vital postpone inside the conduction machine. Without this postpone, the atria and ventricles might contract on the equal time, and blood wouldn’t float efficiently from the atria to the ventricles. The put off inside the AV node bureaucracy plenty of the PR section at the ECG, and part of atrial repolarization can be represented through the PR segment.
The distal portion of the AV node is known as the package of His. The package deal of His splits into two branches inside the interventricular septum: the left package branch and the right package branch. The left package deal department turns on the left ventricle, while the proper bundle branch turns on the proper ventricle.
The left package deal department is brief, splitting into the left anterior fascicle and the left posterior fascicle. The left posterior fascicle is quite quick and extensive, with dual blood deliver, making it in particular resistant to ischemic damage. The left posterior fascicle transmits impulses to the papillary muscles, leading to mitral valve closure. As the left posterior fascicle is shorter and broader than the right, impulses attain the papillary muscle groups just previous to depolarization, and therefore contraction, of the left ventricle myocardium. This permits pre-tensioning of the chordae tendinae, growing the resistance to waft through the mitral valve throughout left ventricular contraction. This mechanism works in the same way as pre-tensioning of vehicle seatbelts.