Certified Rhythm Analysis Technician (CRAT) Practice Exam 2025 – All-in-One Study Guide for Exam Success!

A regular rhythm characterized by a narrow QRS complex, a rate between 40 and 60 beats per minute, and the absence of P waves is indicative of junctional escape rhythm. This type of rhythm occurs when the electrical activity of the heart is initiated from the junction of the atria and ventricles, typically the AV node, rather than the sinoatrial (SA) node, which is why P waves are absent or not discernible.

The narrow QRS complex indicates that there is normal conduction through the ventricles, as opposed to wider complexes that can suggest a ventricular origin. The heart rate falls within the range typical for junctional escape rhythms, which can occur when the SA node fails to initiate impulses, allowing the junctional area to take over as a pacemaker. This results in a reliable yet slower rate compared to normal sinus rhythm.

In contrast, the other rhythms mentioned do not fit this description. Accelerated junctional rhythm would typically show a similar origin but at a higher heart rate, while idioventricular escape rhythms would present with wide QRS complexes due to ventricular origin. Premature ventricular contractions represent an abnormal early beat rather than a sustained rhythm. Therefore, the characteristics of the rhythm and the heart rate clearly point to