CCI ECG Rhythm Interpretation 4 — Questions and Answers
Question 1: A Holter monitor report shows frequent PVCs occurring every other beat. What is this pattern called?
- Ventricular bigeminy (Correct answer)
- Ventricular trigeminy
- Couplets
- Ventricular quadrigeminy
Correct answer: Ventricular bigeminy
Ventricular bigeminy is the pattern of alternating normal sinus beats and premature ventricular contractions (PVC every other beat).
Question 2: Which ECG criterion is used in the Sgarbossa criteria to identify STEMI in the presence of left bundle branch block (LBBB)?
- Concordant ST elevation ≥1 mm in any lead (Correct answer)
- ST elevation ≥2 mm in V1–V3
- New Q waves in inferior leads
- QRS duration >160 ms
Correct answer: Concordant ST elevation ≥1 mm in any lead
Sgarbossa's most specific criterion for STEMI in LBBB is concordant ST elevation ≥1 mm (ST in same direction as QRS deflection).
Question 3: On the ECG, the PR interval is measured from:
- The onset of the P wave to the onset of the QRS complex (Correct answer)
- The peak of the P wave to the peak of the R wave
- The end of the P wave to the end of the QRS complex
- The onset of the QRS to the end of the T wave
Correct answer: The onset of the P wave to the onset of the QRS complex
The PR interval represents atrial depolarization and AV node conduction time, measured from the start of the P wave to the start of the QRS.
Question 4: What does a negative P wave in lead aVR typically indicate?
- Normal sinus rhythm (Correct answer)
- Dextrocardia
- Right atrial enlargement
- Left bundle branch block
Correct answer: Normal sinus rhythm
A negative (inverted) P wave in aVR is a normal finding in sinus rhythm because the normal P wave vector points away from aVR.
Question 5: Which rhythm is characterized by three or more consecutive PVCs?
- Ventricular tachycardia (Correct answer)
- Ventricular flutter
- Accelerated idioventricular rhythm
- Ventricular fibrillation
Correct answer: Ventricular tachycardia
Three or more consecutive PVCs at a rate >100 bpm defines ventricular tachycardia, a potentially life-threatening arrhythmia.
Question 6: In atrial flutter, what is the typical atrial rate (flutter wave rate)?
- 250–350 bpm (Correct answer)
- 150–200 bpm
- 350–450 bpm
- 100–150 bpm
Correct answer: 250–350 bpm
Typical (type I) atrial flutter has an atrial rate of 250–350 bpm producing characteristic sawtooth flutter waves, most visible in inferior leads.
Question 7: A patient's ECG shows a long RP tachycardia with inverted P waves in leads II, III, and aVF. Which arrhythmia should be suspected?
- Permanent junctional reciprocating tachycardia (PJRT) (Correct answer)
- AV nodal reentrant tachycardia (AVNRT)
- Sinus tachycardia
- Atrial tachycardia from the right atrium
Correct answer: Permanent junctional reciprocating tachycardia (PJRT)
PJRT is a long RP tachycardia with inverted inferior P waves caused by a slowly conducting, decremental accessory pathway.
CCI ECG Rhythm Interpretation 4
A Holter monitor report shows frequent PVCs occurring every other beat.
What is this pattern called?