Bundle of His

Bundle of His
Isolated heart conduction system showing bundle of His
Heart cut-away showing the bundle of His. Schematic representation of the atrioventricular bundle of His. The bundle, represented in red, originates near the orifice of the coronary sinus, undergoes slight enlargement to form the AV node. The AV node tapers down into the bundle of His, which passes into the ventricular septum and divides into two bundle branches, the left and right bundles. Sometimes the 'left and right bundles of His' are called Purkyně or Purkinje fibers. The ultimate distribution cannot be completely shown in this diagram.
Details
Identifiers
Latin	fasciculus atrioventricularis
Dorlands /Elsevier	12200650
TA	A12.1.06.005
FMA	9484
Anatomical terminology []

The bundle of His or His bundle is a collection of heart muscle cells specialized for electrical conduction. As part of the electrical conduction system of the heart, it transmits the electrical impulses from the AV node (located between the atria and the ventricles) to the point of the apex of the fascicular branches via the bundle branches. The fascicular branches then lead to the Purkinje fibers, which provide electrical conduction to the ventricles, causing the cardiac muscle of the ventricles to contract at a paced interval.

The bundle of His is an important part of the electrical conduction system of the heart, as it transmits impulses from the atrioventricular node, located at the inferior end of the interatrial septum, to the ventricles of the heart. The intrinsic rate of the bundle of His is 20 or less beats per minute. The bundle of His branches into the left and the right bundle branches, which run along the interventricular septum. The left bundle branch further divides into the left anterior and the left posterior fascicles. These bundles and fascicles give rise to thin filaments known as Purkinje fibers. These fibers distribute the impulse to the ventricular muscle. The ventricular conduction system comprises the bundle branches and the Purkinje networks. It takes about 0.03–0.04 seconds for the impulse to travel from the bundle of His to the ventricular muscle.