What phenomenon might appear on the EKG of a heart transplant patient due to the original SA node activity?

What phenomenon might appear on the EKG of a heart transplant patient due to the original SA node activity?

• A. Flattened P waves
• B. Extra P waves
• C. Absent QRS complexes
• D. Distorted T waves

Answer: (B)

In heart transplant patients, the heart's normal electrical conduction system, including the sinoatrial (SA) node, is often disrupted due to the surgical procedure. The original SA node may still generate electrical impulses even after a transplant, though these impulses may not effectively coordinate with the new heart's conduction pathways. As a result, the presence of extra P waves can be observed on the EKG.

This phenomenon occurs because while the new heart operates under the autonomic regulation of the recipient’s nervous system, the remnants of the original sinus rhythm may still be detected. The extra P waves signify that the original SA node continues to generate impulses independent of the new heart, which can lead to the appearance of multiple P waves in the EKG tracing. This is an important indicator for clinicians to assess the activity of both the transplanted heart and any residual activity from the original heart structures.