ECC Cardiac Rhythm Recognition & Interpretation 2

Question 1

Ventricular tachycardia (VT) is defined as which of the following?

Accepted Answer

Three or more consecutive PVCs at a rate greater than 100 bpm

Answer

Atrial rate greater than ventricular rate with wide QRS

Answer

Narrow-complex tachycardia with aberrant conduction

Answer

P waves occurring after each wide QRS complex only

Question 2

Which ECG change is most specific for ST-elevation myocardial infarction (STEMI)?

Accepted Answer

ST-segment elevation ≥1 mm in two or more contiguous leads

Answer

T-wave inversion in multiple leads

Answer

ST-segment depression greater than 1 mm

Answer

New right bundle branch block alone

Question 3

In Mobitz Type II second-degree AV block, what is the hallmark ECG finding?

Accepted Answer

Sudden non-conducted P wave without prior PR interval changes

Answer

Progressive PR prolongation before a dropped beat

Answer

Complete AV dissociation with equal P and QRS rates

Answer

P waves buried within QRS complexes

Question 4

Which cardiac arrest rhythm requires immediate defibrillation as primary treatment?

Accepted Answer

Ventricular fibrillation

Answer

Pulseless electrical activity (PEA)

Answer

Asystole

Answer

Complete heart block with a pulse

Question 5

Torsades de Pointes is most closely associated with which ECG abnormality?

Accepted Answer

Prolonged QT interval

Answer

Short QT interval

Answer

Delta waves indicating pre-excitation

Answer

ST elevation in inferior leads

Question 6

What is the most common cause of a wide-complex tachycardia encountered in emergency settings?

Accepted Answer

Ventricular tachycardia

Answer

SVT with aberrant conduction

Answer

Hyperkalemia-induced intraventricular delay

Answer

Pre-excitation (WPW) with antidromic conduction

Question 7

For a hemodynamically unstable patient with symptomatic sinus bradycardia, what is the correct first-line pharmacologic treatment per ACLS guidelines?

Accepted Answer

Atropine 0.5 mg IV

Answer

Transcutaneous pacing immediately

Answer

Dopamine infusion at 5 mcg/kg/min

Answer

Adenosine 6 mg IV rapid push