EKG certification Certification EKG Interpretation & Waveforms 2 — Questions and Answers
Question 1: A patient's EKG shows a prolonged QT interval measuring 520 ms. Which of the following is the MOST significant risk associated with this finding?
- Atrial fibrillation
- Torsades de pointes (Correct answer)
- First-degree AV block
- Sinus bradycardia
Correct answer: Torsades de pointes
Prolonged QT interval increases the risk of torsades de pointes, a potentially fatal polymorphic ventricular tachycardia.
Question 2: Which EKG finding is characteristic of Wolff-Parkinson-White (WPW) syndrome?
- Delta wave with shortened PR interval (Correct answer)
- Prolonged PR interval with dropped beats
- ST elevation in contiguous leads
- Peaked T waves with widened QRS
Correct answer: Delta wave with shortened PR interval
WPW syndrome is identified by a delta wave (slurred upstroke of the QRS), shortened PR interval, and widened QRS complex due to an accessory pathway.
Question 3: On a standard 12-lead EKG, which leads directly view the inferior wall of the heart?
- V1, V2, V3
- I, aVL
- II, III, aVF (Correct answer)
- V5, V6
Correct answer: II, III, aVF
Leads II, III, and aVF are the inferior leads that view the bottom surface of the heart supplied primarily by the right coronary artery.
Question 4: A rhythm strip shows an irregularly irregular rhythm with no discernible P waves and a ventricular rate of 130 bpm. What is the MOST likely interpretation?
- Multifocal atrial tachycardia
- Atrial fibrillation with rapid ventricular response (Correct answer)
- Atrial flutter with variable block
- Sinus arrhythmia
Correct answer: Atrial fibrillation with rapid ventricular response
An irregularly irregular rhythm with absent P waves and a rapid ventricular rate is the classic presentation of atrial fibrillation with rapid ventricular response.
Question 5: What does ST segment depression in leads V1-V4 during an acute clinical presentation MOST likely indicate?
- Anterior wall STEMI
- Posterior wall myocardial infarction (Correct answer)
- Pericarditis
- Benign early repolarization
Correct answer: Posterior wall myocardial infarction
Reciprocal ST depression in V1-V4 with acute symptoms suggests a posterior MI, which should be confirmed with posterior leads V7-V9.
Question 6: Which of the following EKG changes is MOST consistent with hyperkalemia?
- Prominent U waves and flattened T waves
- Peaked T waves and widened QRS complex (Correct answer)
- Diffuse ST elevation with PR depression
- Short QT interval with ST depression
Correct answer: Peaked T waves and widened QRS complex
Hyperkalemia classically produces tall peaked T waves, widened QRS complexes, and can progress to sine wave pattern and cardiac arrest if untreated.
EKG certification Certification EKG Interpretation & Waveforms 2
A patient's EKG shows a prolonged QT interval measuring 520 ms.
Which of the following is the MOST significant risk associated with this finding?