Which of the following is NOT classified as an escape rhythm?

Which of the following is NOT classified as an escape rhythm?

• A. Junctional escape
• B. Atrial escape
• C. Ventricular escape
• D. Sinus escape

Answer: (D)

The concept of escape rhythms revolves around mechanisms that allow the heart to maintain an adequate rhythm during periods when the primary pacemaker, usually the sinoatrial (SA) node, fails or slows down. Escape rhythms serve as a backup to generate impulses when normal pacing is disrupted.

Sinus escape is classified differently from other escape rhythms because it originates from the SA node itself. This rhythm occurs when there are temporary pauses or a disruption in the normal conduction pathway, and the SA node resumes pacing once the interference resolves.

On the other hand, junctional, atrial, and ventricular escape rhythms emerge from structures other than the SA node. Junctional escape rhythms arise from the AV node or junctional tissue, atrial escape rhythms come from ectopic pacemakers within the atria, and ventricular escape rhythms originate in the ventricles. These rhythms take over when the SA node is ineffective or absent, thus fitting the definition of an escape rhythm.

In summary, sinus escape originates from the SA node and is not classified as an escape rhythm in the same way that junctional, atrial, and ventricular rhythms are, which is why it is recognized as the correct answer to the question.