Electrical conduction system of the heart

Electrical Conduction System of the Heart

The electrical conduction system of the heart is a network of specialized cardiac muscle cells responsible for the initiation and propagation of electrical impulses that coordinate the contraction of the heart. This system ensures that the heart beats in a synchronized and efficient manner, allowing for effective pumping of blood throughout the body.

Components

The main components of the electrical conduction system include:

• Sinoatrial node (SA node)
• Atrioventricular node (AV node)
• Bundle of His
• Right bundle branch
• Left bundle branch
• Purkinje fibers

Sinoatrial Node

The sinoatrial node (SA node) is located in the upper part of the right atrium near the opening of the superior vena cava. It is often referred to as the natural pacemaker of the heart because it generates electrical impulses that initiate each heartbeat.

Atrioventricular Node

The atrioventricular node (AV node) is situated at the lower part of the interatrial septum near the opening of the coronary sinus. It acts as a gatekeeper, slowing down the electrical impulse before it passes to the ventricles, ensuring that the atria have enough time to contract and empty their blood into the ventricles.

Bundle of His

The Bundle of His is a collection of heart muscle cells specialized for electrical conduction. It transmits the electrical impulses from the AV node to the right and left bundle branches.

Right and Left Bundle Branches

The right bundle branch and left bundle branch are pathways that carry the electrical impulses down the interventricular septum to the Purkinje fibers.

Purkinje Fibers

The Purkinje fibers are a network of fibers that spread throughout the ventricular myocardium. They conduct the electrical impulses rapidly to the ventricular muscle cells, causing the ventricles to contract in a coordinated manner.

Function

The primary function of the electrical conduction system is to ensure that the heart beats in a regular and coordinated manner. The process begins with the generation of an electrical impulse in the SA node, which then spreads through the atria, causing them to contract. The impulse then reaches the AV node, where it is delayed before being transmitted to the Bundle of His, and subsequently to the right and left bundle branches. Finally, the impulse reaches the Purkinje fibers, causing the ventricles to contract.

Related Pages

• Cardiac muscle
• Heart
• Cardiac cycle
• Electrocardiography
• Arrhythmia
• Pacemaker