FREE NCCT EKG Interpretation of Complex Arrhythmias Questions and Answers

Question 1

An EKG strip shows an irregularly irregular rhythm with no discernible P waves and a variable ventricular rate. What is the most likely interpretation?

Accepted Answer

Atrial Fibrillation

Answer

Atrial Flutter

Answer

Sinus Tachycardia

Answer

Ventricular Tachycardia

Question 2

On an EKG, you observe a progressively lengthening PR interval until a QRS complex is dropped. Which type of AV block is this?

Accepted Answer

Second-degree AV block, Mobitz I (Wenckebach)

Answer

First-degree AV block

Answer

Second-degree AV block, Mobitz II

Answer

Third-degree AV block

Question 3

A patient's EKG shows a rapid, wide-complex tachycardia with a regular rhythm. What is the most likely life-threatening arrhythmia?

Accepted Answer

Ventricular Tachycardia (V-Tach)

Answer

Atrial Fibrillation with RVR

Answer

Supraventricular Tachycardia (SVT)

Answer

Sinus Bradycardia

Question 4

Which EKG finding is the hallmark of a third-degree (complete) heart block?

Accepted Answer

Complete dissociation between P waves and QRS complexes

Answer

A constant PR interval that is longer than 0.20 seconds

Answer

Progressively lengthening PR interval with dropped QRS complexes

Answer

A 'sawtooth' pattern of P waves

Question 5

An EKG strip displays a regular rhythm with a ventricular rate of 75 bpm. The atrial rate is 300 bpm, and the baseline has a distinct 'sawtooth' appearance. What is this rhythm?

Accepted Answer

Atrial Flutter

Answer

Atrial Fibrillation

Answer

Sinus Tachycardia

Answer

Junctional Rhythm

Question 6

What EKG characteristic best describes a Premature Ventricular Contraction (PVC)?

Accepted Answer

A wide, bizarre-looking QRS complex that occurs early, not preceded by a P wave

Answer

A narrow QRS complex that occurs earlier than expected

Answer

An inverted P wave preceding a narrow QRS complex

Answer

A dropped QRS complex following a normal P wave

Question 7

An EKG shows a regular rhythm at a rate of 50 bpm. The QRS complexes are narrow, but P waves are absent or inverted. This rhythm most likely originates from the:

Accepted Answer

Atrioventricular (AV) junction

Answer

Sinoatrial (SA) node

Answer

Ventricles

Answer

Atrial tissue