RELIAS Dysrhythmia Basic B Exam Actual Exam 2026/2027:
Complete Exam-Style Questions with Detailed Rationales | 100%
Verified | Pass Guaranteed – A+ Graded
TABLE OF CONTENTS
Section 1 | Cardiac Conduction System & Lead Placement | Q1 – Q10
Section 2 | Sinus & Atrial Arrhythmias | Q11 – Q20
Section 3 | Junctional & Ventricular Rhythms | Q21 – Q30
Section 4 | Atrioventricular Blocks | Q31 – Q40
Section 5 | Pacemaker Rhythms & Clinical Integration | Q41 – Q50
Instructions: Choose the single best answer. Pass: 80% in 90 minutes.
══════════════════════════════════════
SECTION 1: CARDIAC CONDUCTION SYSTEM & LEAD PLACEMENT Q1 – Q10
══════════════════════════════════════
Question 1 of 50
A 58-year-old patient is having a preoperative 12-lead EKG obtained in the holding area.
The technician places the V1 and V2 electrodes in the second intercostal space rather
than the fourth. The ECG shows an rSR' pattern in lead V1. Which finding has most likely
been created by this lead misplacement?
A. An rSR' pattern that may mimic right bundle branch block ✓ CORRECT
B. ST-segment elevation suggesting an anterior wall STEMI
C. Tall R waves suggesting right ventricular hypertrophy
D. Deep Q waves suggesting an old septal infarction
Correct Answer: A
Rationale: Positioning V1 and V2 too high on the chest wall places the electrodes over
the right ventricular outflow tract and can produce an rSR' pattern that resembles right
bundle branch block. True RBBB requires a widened QRS complex with specific
morphologic criteria across multiple leads, not just an isolated rSR' from lead
,misplacement. Always verify precordial electrode placement before diagnosing bundle
branch block or anterior ischemia.
Question 2 of 50
A 65-year-old patient has a routine annual ECG in the cardiology clinic. The tracing
shows a negative P wave in lead I and a positive P wave in lead aVR with otherwise
normal QRS complexes and axis. The patient denies symptoms and the physical exam
is normal. Which technical error best explains this pattern?
A. Dextrocardia with situs inversus totalis
B. Ectopic atrial rhythm from a low right atrial focus
C. Left axis deviation from left anterior fascicular block
D. Reversal of the right and left arm electrodes ✓ CORRECT
Correct Answer: D
Rationale: Swapping the right and left arm electrodes inverts lead I and produces a
positive P wave in aVR while preserving normal QRS morphology, which is one of the
most common technical errors in ECG acquisition. True dextrocardia would also
demonstrate reverse R-wave progression across the precordial leads and right axis
deviation. Checking limb lead placement first avoids misdiagnosing axis deviation or
atrial abnormalities.
Question 3 of 50
A 72-year-old patient is admitted with an inferior wall STEMI and develops a new-onset
second-degree AV block. A cardiology fellow asks the nurse which artery most
commonly supplies the AV node in the general population. Which response is most
accurate?
A. The left anterior descending artery
B. The right coronary artery ✓ CORRECT
C. The left circumflex artery
, D. The posterior descending artery
Correct Answer: B
Rationale: The AV node receives its arterial supply from the right coronary artery in
approximately 90% of individuals, which is why inferior wall myocardial infarctions
frequently present with AV nodal blocks. The left circumflex artery supplies the AV node
in the remaining minority of patients with left-dominant circulation. Understanding this
anatomy helps clinicians anticipate conduction complications during inferior STEMI.
Question 4 of 50
A 45-year-old patient has a routine pre-employment physical. The ECG shows a QRS
duration of 0.14 seconds. A medical student asks the nurse what the QRS complex
physiologically represents. Which explanation is most accurate?
A. The time of atrial depolarization
B. The delay through the AV node
C. The duration of ventricular depolarization ✓ CORRECT
D. The period of ventricular repolarization
Correct Answer: C
Rationale: The QRS complex represents the total duration of ventricular depolarization
as the electrical impulse travels through the bundle branches and Purkinje fibers. The
PR interval covers AV nodal delay, and the T wave represents ventricular repolarization.
A widened QRS indicates delayed ventricular activation from bundle branch block,
ventricular rhythm, or aberrant conduction.
Question 5 of 50
A 55-year-old patient with chest pain arrives in the emergency department. The ECG
shows horizontal ST-segment depression in leads V1 through V3. The attending
Complete Exam-Style Questions with Detailed Rationales | 100%
Verified | Pass Guaranteed – A+ Graded
TABLE OF CONTENTS
Section 1 | Cardiac Conduction System & Lead Placement | Q1 – Q10
Section 2 | Sinus & Atrial Arrhythmias | Q11 – Q20
Section 3 | Junctional & Ventricular Rhythms | Q21 – Q30
Section 4 | Atrioventricular Blocks | Q31 – Q40
Section 5 | Pacemaker Rhythms & Clinical Integration | Q41 – Q50
Instructions: Choose the single best answer. Pass: 80% in 90 minutes.
══════════════════════════════════════
SECTION 1: CARDIAC CONDUCTION SYSTEM & LEAD PLACEMENT Q1 – Q10
══════════════════════════════════════
Question 1 of 50
A 58-year-old patient is having a preoperative 12-lead EKG obtained in the holding area.
The technician places the V1 and V2 electrodes in the second intercostal space rather
than the fourth. The ECG shows an rSR' pattern in lead V1. Which finding has most likely
been created by this lead misplacement?
A. An rSR' pattern that may mimic right bundle branch block ✓ CORRECT
B. ST-segment elevation suggesting an anterior wall STEMI
C. Tall R waves suggesting right ventricular hypertrophy
D. Deep Q waves suggesting an old septal infarction
Correct Answer: A
Rationale: Positioning V1 and V2 too high on the chest wall places the electrodes over
the right ventricular outflow tract and can produce an rSR' pattern that resembles right
bundle branch block. True RBBB requires a widened QRS complex with specific
morphologic criteria across multiple leads, not just an isolated rSR' from lead
,misplacement. Always verify precordial electrode placement before diagnosing bundle
branch block or anterior ischemia.
Question 2 of 50
A 65-year-old patient has a routine annual ECG in the cardiology clinic. The tracing
shows a negative P wave in lead I and a positive P wave in lead aVR with otherwise
normal QRS complexes and axis. The patient denies symptoms and the physical exam
is normal. Which technical error best explains this pattern?
A. Dextrocardia with situs inversus totalis
B. Ectopic atrial rhythm from a low right atrial focus
C. Left axis deviation from left anterior fascicular block
D. Reversal of the right and left arm electrodes ✓ CORRECT
Correct Answer: D
Rationale: Swapping the right and left arm electrodes inverts lead I and produces a
positive P wave in aVR while preserving normal QRS morphology, which is one of the
most common technical errors in ECG acquisition. True dextrocardia would also
demonstrate reverse R-wave progression across the precordial leads and right axis
deviation. Checking limb lead placement first avoids misdiagnosing axis deviation or
atrial abnormalities.
Question 3 of 50
A 72-year-old patient is admitted with an inferior wall STEMI and develops a new-onset
second-degree AV block. A cardiology fellow asks the nurse which artery most
commonly supplies the AV node in the general population. Which response is most
accurate?
A. The left anterior descending artery
B. The right coronary artery ✓ CORRECT
C. The left circumflex artery
, D. The posterior descending artery
Correct Answer: B
Rationale: The AV node receives its arterial supply from the right coronary artery in
approximately 90% of individuals, which is why inferior wall myocardial infarctions
frequently present with AV nodal blocks. The left circumflex artery supplies the AV node
in the remaining minority of patients with left-dominant circulation. Understanding this
anatomy helps clinicians anticipate conduction complications during inferior STEMI.
Question 4 of 50
A 45-year-old patient has a routine pre-employment physical. The ECG shows a QRS
duration of 0.14 seconds. A medical student asks the nurse what the QRS complex
physiologically represents. Which explanation is most accurate?
A. The time of atrial depolarization
B. The delay through the AV node
C. The duration of ventricular depolarization ✓ CORRECT
D. The period of ventricular repolarization
Correct Answer: C
Rationale: The QRS complex represents the total duration of ventricular depolarization
as the electrical impulse travels through the bundle branches and Purkinje fibers. The
PR interval covers AV nodal delay, and the T wave represents ventricular repolarization.
A widened QRS indicates delayed ventricular activation from bundle branch block,
ventricular rhythm, or aberrant conduction.
Question 5 of 50
A 55-year-old patient with chest pain arrives in the emergency department. The ECG
shows horizontal ST-segment depression in leads V1 through V3. The attending
