CCT CCT - Certified Cardiographic Technician Cardiac Medications and ECG Effects Questions and Answers 1 — Questions and Answers
Question 1: Which ECG change is most commonly associated with digoxin toxicity?
- Prolonged PR interval with scooped ST depression (Correct answer)
- Peaked T waves
- Delta waves
- Widened QRS complex
Correct answer: Prolonged PR interval with scooped ST depression
Digoxin toxicity classically produces a prolonged PR interval and the characteristic 'scooped' or 'Salvador Dali mustache' ST depression pattern.
Question 2: A patient taking amiodarone is most likely to show which ECG finding?
- Shortened QT interval
- Prolonged QT interval (Correct answer)
- Shortened PR interval
- Elevated J point
Correct answer: Prolonged QT interval
Amiodarone prolongs repolarization, resulting in a lengthened QT interval, which increases the risk for torsades de pointes.
Question 3: Which class of antiarrhythmic drugs works primarily by blocking sodium channels and is known to widen the QRS complex?
- Class II (beta-blockers)
- Class III (potassium channel blockers)
- Class I (sodium channel blockers) (Correct answer)
- Class IV (calcium channel blockers)
Correct answer: Class I (sodium channel blockers)
Class I antiarrhythmics (e.g., flecainide, quinidine) block fast sodium channels, slowing conduction and widening the QRS complex.
Question 4: Beta-blockers (Class II antiarrhythmics) produce which primary ECG effect?
- Shortened PR interval
- Widened QRS
- Prolonged PR interval and slowed heart rate (Correct answer)
- ST elevation
Correct answer: Prolonged PR interval and slowed heart rate
Beta-blockers slow AV nodal conduction, prolonging the PR interval, and decrease the overall heart rate by reducing sympathetic drive.
Question 5: Hyperkalemia is most associated with which ECG change?
- Peaked, tall T waves (Correct answer)
- Flat T waves
- Prolonged QT
- Delta waves
Correct answer: Peaked, tall T waves
Elevated serum potassium causes tall, peaked, narrow T waves, which are often the earliest ECG sign of hyperkalemia.
Question 6: A patient receiving IV adenosine during an SVT episode would most likely show which transient ECG finding?
- Ventricular tachycardia
- Complete AV block with a brief asystole pause (Correct answer)
- ST elevation
- Prolonged QT
Correct answer: Complete AV block with a brief asystole pause
Adenosine transiently blocks AV conduction, causing a brief period of complete AV block or asystole that typically terminates SVT.
CCT CCT - Certified Cardiographic Technician Cardiac Medications and ECG Effects Questions and Answers 1
Which ECG change is most commonly associated with digoxin toxicity?