Free RCIS Electrophysiology Questions and Answers — Questions and Answers
Question 1: Which component of the cardiac conduction system is responsible for the intrinsic pacing of the heart?
- Atrioventricular (AV) node
- Bundle of His
- Sinoatrial (SA) node (Correct answer)
- Purkinje fibers
Correct answer: Sinoatrial (SA) node
The Sinoatrial (SA) node is the component of the cardiac conduction system responsible for the intrinsic pacing of the heart. Often called the heart's natural pacemaker, the SA node generates electrical impulses that initiate the heartbeat. These impulses then spread through the atria and to the AV node, coordinating the heart's contractions.
Question 2: During an electrophysiology study, what is the purpose of programmed electrical stimulation (PES)?
- To measure the heart's response to exercise
- To determine the duration of the refractory period
- To assess the mechanical function of the heart valves
- To induce arrhythmias and evaluate the heart's electrical pathways (Correct answer)
Correct answer: To induce arrhythmias and evaluate the heart's electrical pathways
During an electrophysiology study, the purpose of programmed electrical stimulation (PES) is to induce arrhythmias and evaluate the heart's electrical pathways. PES involves delivering precisely timed electrical impulses to the heart through catheters. This technique helps identify the origin and mechanisms of arrhythmias, guiding treatment strategies.
Question 3: What does a prolonged QT interval on an electrocardiogram (ECG) indicate?
- Ventricular hypertrophy
- Hyperkalemia
- Prolonged ventricular repolarization (Correct answer)
- Sinus bradycardia
Correct answer: Prolonged ventricular repolarization
A prolonged QT interval on an electrocardiogram (ECG) indicates prolonged ventricular repolarization. The QT interval represents the time it takes for the ventricles to depolarize and repolarize. An extended QT interval signifies a delay in the heart's electrical recovery, which can increase the risk of developing dangerous ventricular arrhythmias.
Question 4: Which medication is commonly used to terminate supraventricular tachycardia (SVT) during an electrophysiology study?
- Lidocaine
- Atropine
- Adenosine (Correct answer)
- Amiodarone
Correct answer: Adenosine
Adenosine is a medication commonly used to terminate supraventricular tachycardia (SVT) during an electrophysiology study. Adenosine works by temporarily blocking the atrioventricular (AV) node, which often interrupts the re-entrant electrical pathway responsible for SVT. Its rapid onset and short duration of action make it effective for acute termination.
Question 5: In an ECG, what does the P wave represent?
- Atrial depolarization (Correct answer)
- Ventricular depolarization
- Atrial repolarization
- Ventricular repolarization
Correct answer: Atrial depolarization
The P wave on an ECG represents the electrical activity associated with atrial depolarization. This is the initial electrical impulse that causes the atria to contract, pushing blood into the ventricles. It signifies the start of the cardiac cycle's electrical events, preceding mechanical atrial contraction.
Which component of the cardiac conduction system is responsible for the intrinsic pacing of the heart?