CCI ECG Rhythm Interpretation 2

Question 1

A patient's ECG shows a regular rhythm at 150 bpm with narrow QRS complexes and no visible P waves. Which rhythm is most likely?

Accepted Answer

Atrial flutter with 2:1 block

Answer

Atrial flutter typically produces a ventricular rate of 150 bpm when 2:1 AV conduction is present, often hiding flutter waves in the QRS or T wave.

Question 2

Which ECG feature best distinguishes Wolff-Parkinson-White (WPW) syndrome from a bundle branch block?

Accepted Answer

Delta wave and short PR interval

Answer

WPW is characterized by a delta wave (slurred QRS upstroke) and a short PR interval (<0.12 sec) due to accessory pathway pre-excitation.

Question 3

An ECG shows regular P waves at 75 bpm, but only every other P wave conducts. The PR interval of conducted beats is constant. What is the rhythm?

Accepted Answer

Second-degree AV block, Mobitz type II

Answer

2:1 conduction with a constant PR interval on conducted beats and non-conducted P waves is consistent with Mobitz type II second-degree AV block.

Question 4

What is the significance of a U wave on the ECG?

Accepted Answer

It often indicates hypokalemia when prominent

Answer

Prominent U waves are a classic ECG sign of hypokalemia; they appear after the T wave and can mimic a prolonged QT interval.

Question 5

A patient with no pulse has an ECG showing organized electrical activity. What is this condition called?

Accepted Answer

Pulseless electrical activity (PEA)

Answer

PEA is defined as organized cardiac electrical activity on ECG without a corresponding palpable pulse, requiring CPR and treatment of reversible causes.

CCI - Cardiovascular Credentialing International Practice Test

CCI - Cardiovascular Credentialing International Practice Test

CCI ECG Rhythm Interpretation 2