CCT - Certified Cardiographic Technician Rhythm Analysis: Ventricular/Blocks Questions and Answers

Question 1

A patient's ECG strip shows a regular rhythm with a rate of 45 bpm. The QRS complexes are wide (0.14 seconds), and there are no discernible P waves associated with the QRS complexes. Which of the following rhythms is most likely represented?

Accepted Answer

Idioventricular rhythm

Answer

Idioventricular rhythm is characterized by a regular, slow ventricular rate (typically 20-40 bpm, but sometimes up to 50), wide QRS complexes (≥0.12s), and the absence of associated P waves. It acts as a safety mechanism when higher pacemakers fail.

Question 2

Which of the following ECG findings is the hallmark characteristic of Third-Degree Atrioventricular (AV) Block?

Accepted Answer

Complete AV dissociation with atrial rate faster than ventricular rate

Answer

Third-degree, or complete, AV block is defined by the complete absence of conduction between the atria and ventricles. This results in AV dissociation, where the P waves (atrial activity) and QRS complexes (ventricular activity) are independent of each other, with the atrial rate typically being faster than the ventricular escape rate.

Question 3

A CCT observes a rhythm strip where the PR interval progressively lengthens for three consecutive beats, followed by a P wave that is not followed by a QRS complex. This pattern then repeats. How should this rhythm be identified?

Accepted Answer

Mobitz I Second-Degree AV Block (Wenckebach)

Answer

The classic finding for Mobitz I Second-Degree AV Block, also known as Wenckebach phenomenon, is a progressive prolongation of the PR interval until a P wave is blocked and a QRS complex is 'dropped'. The cycle then typically resets.

Question 4

A patient's monitor displays a regular, wide-complex tachycardia at a rate of 180 bpm. Which of the following features, if present, would most definitively confirm the rhythm is Ventricular Tachycardia (VT) rather than Supraventricular Tachycardia (SVT) with aberrancy?

Accepted Answer

Presence of fusion and capture beats

Answer

While several criteria can suggest VT, the presence of AV dissociation, demonstrated by capture or fusion beats, is a pathognomonic sign of Ventricular Tachycardia. Capture beats are normal-looking QRS complexes that occur when a sinus beat is conducted to the ventricles during the tachycardia, and fusion beats are a hybrid of a sinus and ventricular beat.

Question 5

When analyzing an ECG for Premature Ventricular Contractions (PVCs), which characteristic is typically observed?

Accepted Answer

A wide, bizarre QRS complex followed by a full compensatory pause

Answer

PVCs originate from an ectopic focus in the ventricles. This results in a premature, wide (≥0.12s), and abnormally shaped QRS complex because the impulse spreads through the myocardium instead of the rapid conduction pathway. It is typically followed by a compensatory pause, as the sinoatrial node's rhythm is not interrupted.

CCT - Certified Cardiographic Technician Exam Practice Test

CCT - Certified Cardiographic Technician Exam Practice Test

CCT - Certified Cardiographic Technician Rhythm Analysis: Ventricular/Blocks Questions and Answers