What is a common characteristic of third-degree heart block?

A common characteristic of third-degree heart block is that the atria and ventricles beat independently. In third-degree heart block, there is a complete failure of communication between the atria and the ventricles due to a disruption in the normal conduction pathway. This means that the electrical impulses generated by the atria do not reach the ventricles, leading to the atria contracting at one rate, while the ventricles contract at a separate, often much slower rate. This dissociation results in two independent rhythms: one for the atria and another for the ventricles, which is a hallmark of third-degree heart block.

Understanding this characteristic is crucial for recognizing the condition’s implications for cardiac function and the need for possible intervention or pacing, as the independent beating can lead to inefficient blood flow and hemodynamic instability.