CCT CCT - Certified Cardiographic Technician 12-Lead ECG Interpretation and Cardiac Conditions Questions and Answers 1 — Questions and Answers
Question 1: Which leads make up the inferior territory of the heart on a 12-lead ECG?
- I, aVL, V5, V6
- II, III, aVF (Correct answer)
- V1, V2, V3
- V4, V5, V6
Correct answer: II, III, aVF
Leads II, III, and aVF face the inferior wall of the left ventricle, which is supplied primarily by the right coronary artery (RCA).
Question 2: ST elevation in leads V1-V4 combined with a new right bundle branch block most strongly suggests:
- Posterior MI
- Anterior MI with septal involvement (Correct answer)
- Inferior MI
- Pericarditis
Correct answer: Anterior MI with septal involvement
ST elevation in V1-V4 reflects anterior wall STEMI, and a new RBBB can indicate septal involvement, often due to LAD artery occlusion.
Question 3: What is the hallmark ECG finding of left ventricular hypertrophy (LVH) using the Sokolow-Lyon criterion?
- S in V1 + R in V5 or V6 > 35 mm (Correct answer)
- R in aVL > 11 mm only
- QRS duration > 120 ms
- ST elevation in V1-V2
Correct answer: S in V1 + R in V5 or V6 > 35 mm
The Sokolow-Lyon criterion defines LVH as the sum of the S wave in V1 and the tallest R wave in V5 or V6 exceeding 35 mm.
Question 4: Reciprocal ST changes seen in leads I and aVL during an inferior MI indicate:
- Posterior extension of the MI
- Normal variant
- Anterior ischemia
- Reciprocal depression confirming inferior STEMI and its territory (Correct answer)
Correct answer: Reciprocal depression confirming inferior STEMI and its territory
ST depression in I and aVL is the expected reciprocal (mirror image) change that confirms inferior STEMI in II, III, aVF, helping to rule out pericarditis or artifact.
Question 5: A 12-lead ECG shows ST elevation in V1-V2, deep S waves in I, and right axis deviation. Which condition does this pattern suggest?
- Left ventricular hypertrophy
- Right ventricular hypertrophy (RVH) or strain (Correct answer)
- Lateral MI
- Wolff-Parkinson-White syndrome
Correct answer: Right ventricular hypertrophy (RVH) or strain
Right axis deviation, tall R in V1, and deep S in lateral leads are classic features of RVH or right ventricular strain, often seen in pulmonary hypertension or PE.
Question 6: Which ECG pattern is described as diffuse concave ('saddle-back') ST elevation in most leads with PR depression, without reciprocal changes?
- STEMI
- Pericarditis (Correct answer)
- Brugada syndrome
- Early repolarization variant
Correct answer: Pericarditis
Acute pericarditis causes diffuse concave ST elevation and PR depression (especially in II and aVF) in most leads without the reciprocal depression seen in STEMI.
CCT CCT - Certified Cardiographic Technician 12-Lead ECG Interpretation and Cardiac Conditions Questions and Answers 1
Which leads make up the inferior territory of the heart on a 12-lead ECG?