ECG Rhythm Interpretation Flashcards

A Holter monitor report shows frequent PVCs occurring every other beat. What is this pattern called?

Answer: Ventricular bigeminy

Ventricular bigeminy is the pattern of alternating normal sinus beats and premature ventricular contractions (PVC every other beat).

Which ECG criterion is used in the Sgarbossa criteria to identify STEMI in the presence of left bundle branch block (LBBB)?

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).

On the ECG, the PR interval is measured from:

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.

What does a negative P wave in lead aVR typically indicate?

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.

Which rhythm is characterized by three or more consecutive PVCs?

Answer: Ventricular tachycardia

Three or more consecutive PVCs at a rate >100 bpm defines ventricular tachycardia, a potentially life-threatening arrhythmia.

In atrial flutter, what is the typical atrial rate (flutter wave rate)?

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.

A patient's ECG shows a long RP tachycardia with inverted P waves in leads II, III, and aVF. Which arrhythmia should be suspected?

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.