Question

An EKG shows a regular rate of 50 beats per minute. The QRS is narrow and there is no visible P wave. What is the most likely diagnosis?

Answer 1

The absence of P waves with a narrow QRS and a heart rate of 50 beats per minute on an EKG indicates a junctional rhythm, with the rhythm originating from the AV junction.

Step-by-step explanation:

An EKG showing a regular rate of 50 beats per minute, a narrow QRS, and no visible P wave is most indicative of a junctional rhythm. Normally, the P wave represents atrial depolarization, which then leads to atrial contraction, and is followed by the QRS complex. The absence of P waves suggests that the atria are not dictating the heart rhythm, and with a narrow QRS, it implies that the impulse is coming from the AV junction, where the atria and ventricles meet. Hence, the most likely diagnosis is a junctional rhythm, which typically presents with a heart rate of 40-60 beats per minute.