CVT ECG Interpretation & Analysis 3 — Questions and Answers
Question 1: In atrial flutter, the atrial rate is typically:
- 100–150 bpm
- 150–250 bpm
- 250–350 bpm (Correct answer)
- 350–600 bpm
Correct answer: 250–350 bpm
Atrial flutter produces a characteristic sawtooth pattern at an atrial rate of 250–350 bpm, most commonly around 300 bpm.
Question 2: ST depression that is horizontal or downsloping in leads V4-V6 during an exercise stress test is most suggestive of:
- Normal physiologic response
- Myocardial ischemia (Correct answer)
- Benign early repolarization
- Left ventricular hypertrophy
Correct answer: Myocardial ischemia
Horizontal or downsloping ST depression ≥1 mm at 80 ms after the J point during stress testing is the standard criterion for inducible ischemia.
Question 3: Which ECG pattern is seen in Brugada syndrome?
- ST elevation in V1-V3 with coved morphology (Correct answer)
- ST depression in inferior leads
- Tall R wave in V1 with right axis deviation
- Epsilon wave in V1-V3
Correct answer: ST elevation in V1-V3 with coved morphology
Brugada syndrome shows a coved-type ST elevation (≥2 mm) in right precordial leads V1-V3, associated with risk of sudden cardiac death.
Question 4: A first-degree AV block is defined by a PR interval of:
- >120 ms
- >200 ms (Correct answer)
- >300 ms
- >160 ms
Correct answer: >200 ms
First-degree AV block is diagnosed when the PR interval consistently exceeds 200 ms (5 small boxes) with all P waves conducted.
Question 5: Which rhythm shows progressive lengthening of the PR interval until a QRS is dropped?
- Mobitz type II block
- Complete heart block
- Mobitz type I (Wenckebach) block (Correct answer)
- First-degree AV block
Correct answer: Mobitz type I (Wenckebach) block
Mobitz type I (Wenckebach) block features progressive PR prolongation until one P wave is not conducted, then the cycle resets.
Question 6: Epsilon waves on an ECG are pathognomonic of which condition?
- Hypertrophic cardiomyopathy
- Arrhythmogenic right ventricular cardiomyopathy (ARVC) (Correct answer)
- Brugada syndrome
- Long QT syndrome
Correct answer: Arrhythmogenic right ventricular cardiomyopathy (ARVC)
Epsilon waves — small positive deflections after the QRS in V1-V3 — represent delayed right ventricular depolarization and are hallmark findings of ARVC.
Question 7: On the ECG, lead aVR views the heart from which vantage point?
- Left lateral wall
- Inferior wall
- Right shoulder (base of heart) (Correct answer)
- Posterior wall
Correct answer: Right shoulder (base of heart)
Lead aVR looks at the heart from the right shoulder, viewing the base and the cavity of the left ventricle; it is often a mirror image of inferior leads.
CVT ECG Interpretation & Analysis 3
In atrial flutter, the atrial rate is typically: