What occurs in complete heart block?

In complete heart block, there is a total cessation of electrical conduction between the atria and ventricles, which typically occurs at the atrioventricular (AV) node. This means that the signals generated by the sinoatrial (SA) node, which are responsible for initiating heartbeats, are unable to propagate to the ventricles. As a result, the atria can beat independently from the ventricles, leading to a disconnection in the coordinated rhythm that is essential for effective heart function.

When this complete block occurs, the ventricles do not receive the impulses needed for contraction, which can result in a very slow heartbeat and potentially serious complications. This condition often necessitates medical intervention, such as the placement of a pacemaker, to restore effective heart rhythm and maintain adequate blood circulation.

Recognizing the nature of complete heart block is crucial for understanding cardiac physiology and the implications of arrhythmias. In this context, the other options do not accurately describe the condition: partial blocks or "skips" in rhythm reflect different types of conduction disturbances, not the total disruption that characterizes complete heart block.