What is the role of the Purkinje fibers in cardiac conduction?

The Purkinje fibers play a crucial role in the cardiac conduction system, primarily by distributing impulses to the ventricles. These specialized fibers are part of the conduction pathway that ensures effective and coordinated contractions of the heart. After the electrical impulse is generated in the sinoatrial (SA) node and travels through the atrioventricular (AV) node, it reaches the bundle of His and then travels down the right and left bundle branches into the Purkinje fibers.

The primary function of the Purkinje fibers is to rapidly transmit the electrical impulses throughout the ventricles, allowing the myocardial cells to contract in a synchronized manner. This coordinated contraction is essential for the effective pumping of blood from the heart to the rest of the body. By ensuring that the impulse reaches all parts of the ventricles almost simultaneously, the Purkinje fibers enable a strong and efficient ventricular contraction. This role is vital for maintaining proper heart function and blood circulation.

In contrast, generating impulses is primarily the role of the SA node, while regulating heart rate involves various factors, including autonomic nervous system inputs to the SA node. The transmission of impulses to the atria is also performed by the SA and AV nodes rather than by the Purkinje fibers, which are specifically