Are patients typically symptomatic with a third-degree AV block?

In third-degree atrioventricular (AV) block, also known as complete heart block, there is a complete disconnection between the electrical signals from the atria and ventricles. This means that while the atria may still be beating at their normal rate, the ventricles typically respond at a much slower rate, often leading to inadequate blood flow and potential symptoms of heart failure.

Patients with third-degree AV block frequently present with various symptoms due to this disconnect, including fatigue, dizziness, and syncope (fainting). The severity of symptoms may vary depending on the underlying heart rate and the patient's overall cardiovascular status. Some may experience severe symptoms while others may be only mildly affected, yet many will not remain asymptomatic. Therefore, it is common for these patients to exhibit symptoms, especially as the condition progresses or during physical exertion.

Understanding this condition is vital in critical care settings, as timely recognition and intervention can prevent complications associated with hemodynamic instability.