AVkonduksjon

AVkonduksjon refers to the conduction of electrical impulses through the atrioventricular node (AV node) in the heart. This node is a crucial component of the cardiac conduction system, responsible for delaying the electrical signal from the atria to the ventricles. This delay is essential for allowing the atria to complete their contraction and effectively pump blood into the ventricles before the ventricles themselves begin to contract.

The process begins when an electrical impulse generated by the sinoatrial (SA) node, the heart's natural pacemaker, travels through the atria. Upon reaching the AV node, the impulse slows down significantly. This slowing is due to the unique electrical properties of the AV nodal cells, including their smaller size and fewer gap junctions compared to atrial cells. After the delay, the impulse is then transmitted to the His bundle, which branches into the left and right bundle branches, ultimately leading to ventricular depolarization and contraction.

Dysfunction of AVkonduksjon can lead to various heart rhythm abnormalities, known as arrhythmias. For example, a complete heart block occurs when the AV node fails to conduct any impulses from the atria to the ventricles, resulting in the ventricles beating independently at a much slower rate. Other conditions like AV nodal reentrant tachycardia involve a re-entry circuit within the AV node, causing rapid heart rates. The assessment of AVkonduksjon is a key part of electrocardiogram (ECG) interpretation.