What does a continuous reentry circuit associated with AVNRT do?

What does a continuous reentry circuit associated with AVNRT do?

• A. It sporadically causes QRS complexes
• B. It paces the atria and ventricles rapidly
• C. It causes a slowed heart rate
• D. It causes atrial flutter

Answer: (B)

A continuous reentry circuit associated with AV nodal reentrant tachycardia (AVNRT) is known for creating rapid heartbeats due to its mechanism of reentry. In AVNRT, there are two pathways in the atrioventricular node: a fast conduction pathway and a slow conduction pathway. The reentry circuit allows electrical impulses to travel rapidly around these pathways, leading to a rapid firing rate from the atria and, consequently, a rapid response in the ventricles.

This rapid pacing of both the atria and ventricles contributes to the characteristic high heart rate experienced during AVNRT episodes, which can often exceed 150 beats per minute. This is why the correct answer highlights that a continuous reentry circuit in AVNRT paces both the atria and ventricles rapidly, causing a significant increase in heart rate and potentially leading to symptoms such as palpitations or dizziness.

Understanding this mechanism is crucial for recognizing the clinical manifestations of AVNRT and can aid in appropriate management strategies for patients experiencing this type of tachycardia.