INTERPRETATION: 2026/2027 WITH
CORRECT/ACCURATE ANSWERS, 100 EXAM
QUESTIONS (BASIC LEVEL)
Each item: rhythm description you’d see on ECG, four choices, correct
answer, brief rationale.
KAISER-STYLE/KP RHYTHM
INTERPRETATION
1. A regular rhythm, rate 72 bpm, P waves present before every QRS, PR interval 0.16 sec, QRS
narrow. What is the rhythm?
A. Sinus bradycardia
B. Sinus rhythm (normal sinus)
C. Atrial fibrillation
D. Junctional rhythm
Answer: B — Sinus rhythm (normal sinus)
Rationale: Normal rate (60–100), P before each QRS, normal PR and QRS.
2. Regular rhythm, rate 48 bpm, P waves present, PR 0.18 sec, QRS narrow. What is this?
A. Sinus bradycardia
B. Sinus tachycardia
C. 2nd-degree AV block Mobitz II
D. Ventricular escape rhythm
Answer: A — Sinus bradycardia
Rationale: Rate <60 with normal P-QRS morphology consistent with sinus origin.
3. Irregularly irregular rhythm, absent P waves, fibrillatory baseline, variable R–R intervals. Diagnosis?
A. Atrial flutter
B. Atrial fibrillation
C. Multifocal atrial tachycardia
D. Sinus arrhythmia
Answer: B — Atrial fibrillation
Rationale: Classic irregularly irregular with no discrete P waves.
,4. Regular sawtooth flutter waves at ~300/min with ventricular rate 150 (2:1 conduction). What
rhythm?
A. Atrial fibrillation
B. Atrial flutter with 2:1 block
C. Multifocal atrial tachycardia
D. SVT
Answer: B — Atrial flutter with 2:1 block
Rationale: Atrial rate ~300 and sawtooth pattern indicate flutter; 2:1 gives ventricular 150.
5. Narrow complex tachycardia rate 180 bpm, P waves hidden in QRS, sudden onset and termination.
Most likely?
A. Sinus tachycardia
B. Ventricular tachycardia
C. Supraventricular tachycardia (SVT) — AVNRT/AVRT
D. Atrial flutter
Answer: C — SVT (AVNRT/AVRT)
Rationale: Paroxysmal narrow tachycardia with abrupt start/stop suggests SVT.
6. Wide QRS complex, rate 160 bpm, regular, no P waves. Likely rhythm?
A. Ventricular tachycardia (monomorphic)
B. SVT with aberrancy
C. Sinus tachycardia
D. Atrial fibrillation
Answer: A — Ventricular tachycardia (monomorphic)
Rationale: Wide regular tachycardia without P waves suggests VT until proven otherwise.
7. Single, premature, wide QRS complex with compensatory pause; no preceding P wave. What is it?
A. PAC
B. PVC
C. PAC with aberrancy
D. Junctional beat
Answer: B — PVC (premature ventricular contraction)
Rationale: Wide QRS without P indicates ventricular premature beat.
8. Premature P wave with different morphology followed by narrow QRS. What is it?
A. PVC
B. PAC (premature atrial contraction)
C. Junctional escape beat
D. Ventricular escape beat
Answer: B — PAC
Rationale: Ectopic atrial origin produces abnormal P morphology before normal QRS.
, 9. Grouped beating: three PVCs in a row forming a run at 130 bpm. This is called:
A. Bigeminy
B. Trigeminy
C. Ventricular tachycardia (non-sustained VT)
D. Couplets
Answer: C — Non-sustained VT (run) or sustained depending on duration
Rationale: Three or more consecutive PVCs constitute ventricular tachycardia; if <30 sec, non-
sustained.
10. Regular rhythm, P waves absent, narrow QRS, rate 55 bpm, PR not measurable. What’s the rhythm?
A. Junctional escape rhythm
B. Sinus bradycardia
C. Atrial fibrillation
D. Ventricular escape rhythm
Answer: A — Junctional escape rhythm
Rationale: No P waves and rate 40–60 suggests junctional pacemaker.
11. PR intervals progressively lengthen until a beat is dropped (missing QRS). What type of AV block?
A. 1st-degree AV block
B. 2nd-degree AV block Mobitz I (Wenckebach)
C. 2nd-degree AV block Mobitz II
D. 3rd-degree AV block
Answer: B — Mobitz I (Wenckebach)
Rationale: Classic progressive PR prolongation then dropped beat.
12. PR intervals constant, then sudden dropped QRS without PR prolongation. Which block?
A. Mobitz I
B. Mobitz II
C. 1st-degree AV block
D. 3rd-degree AV block
Answer: B — Mobitz II
Rationale: Fixed PR with unexpected dropped beats indicates Mobitz II.
13. P waves and QRS complexes present but no relationship; atrial rate 100, ventricular rate 40.
Diagnosis?
A. 2:1 AV block
B. 1st-degree AV block
C. 3rd-degree (complete) heart block
D. Atrial fibrillation
Answer: C — 3rd-degree AV block
Rationale: Complete AV dissociation indicates complete heart block.