📝 Step 5 — KMU Past Papers & Exam Learning

This section contains KMU-style past paper questions designed to strengthen conceptual understanding. Focus on understanding explanations rather than memorizing answers.

🎯 How to Study KMU Past Papers

• Read the question carefully.
• Think about the answer before looking.
• Read the explanation slowly.
• Understand the reasoning behind the correct answer.
• Revise difficult questions again.

MCQ 1

Question:
A 66-year-old man presents with dizziness. ECG shows a PR interval of 240 milliseconds, and every P wave is followed by a QRS complex. Which conduction abnormality is present?

Options:
Sinus node dysfunction
First-degree AV block
Mobitz type I AV block
Mobitz type II AV block
Complete AV block

Correct Answer:
First-degree AV block

Explanation:
First-degree AV block is characterized by a prolonged PR interval greater than 200 milliseconds with conduction of every atrial impulse.

MCQ 2

Question:
A patient has bradycardia with regular P waves and regular QRS complexes, but no consistent relationship exists between them. Which diagnosis is most likely?

Options:
Atrial flutter with fixed block
Sinus bradycardia
First-degree AV block
Complete AV block
Mobitz type I AV block

Correct Answer:
Complete AV block

Explanation:
Independent atrial and ventricular activity indicates AV dissociation, the hallmark of complete heart block.

MCQ 3

Question:
A 72-year-old woman develops new-onset atrial fibrillation. Which investigation is most useful for identifying a reversible endocrine precipitant?

Options:
Serum amylase
Thyroid function tests
Coagulation profile
Serum uric acid
Arterial blood gases

Correct Answer:
Thyroid function tests

Explanation:
Thyrotoxicosis is an important reversible cause of atrial fibrillation and should be excluded in new-onset cases.

MCQ 4

Question:
A patient with persistent atrial fibrillation has controlled ventricular rate but remains at high risk of embolic stroke. Which management component addresses this risk most directly?

Options:
Rhythm monitoring
AV nodal blockade
Anticoagulation assessment
Electrolyte replacement
Exercise restriction

Correct Answer:
Anticoagulation assessment

Explanation:
Stroke prevention is a separate management decision from rate control and requires thromboembolic-risk assessment.

MCQ 5

Question:
A patient with atrial fibrillation has rapid ventricular response during sepsis. Digoxin provides inadequate control. What best explains this poor response?

Options:
Reduced renal elimination
Increased atrial refractoriness
High sympathetic activity
Excessive sodium-channel blockade
Reduced potassium-channel activity

Correct Answer:
High sympathetic activity

Explanation:
Digoxin relies mainly on vagal effects at the AV node and is less effective during marked sympathetic stimulation.

MCQ 6

Question:
An ECG shows regular atrial activity at approximately 300/min with a saw-tooth baseline and a ventricular rate of 150/min. Which rhythm is most likely?

Options:
Atrial fibrillation
Atrial flutter with 2:1 conduction
AV nodal re-entry tachycardia
Sinus tachycardia
Ventricular tachycardia

Correct Answer:
Atrial flutter with 2:1 conduction

Explanation:
Saw-tooth flutter waves with a ventricular rate near half the atrial rate indicate atrial flutter with 2:1 AV conduction.

MCQ 7

Question:
A patient has three consecutive ventricular premature beats that terminate spontaneously after eight seconds. Which term best describes this rhythm?

Options:
Sustained ventricular tachycardia
Ventricular fibrillation
Nonsustained ventricular tachycardia
Atrial tachycardia with aberrancy
Accelerated junctional rhythm

Correct Answer:
Nonsustained ventricular tachycardia

Explanation:
A run of ventricular tachycardia that terminates spontaneously within 30 seconds is classified as nonsustained VT.

MCQ 8

Question:
Which investigation is most useful for detecting intermittent ventricular arrhythmias when a resting ECG is normal?

Options:
Chest radiography
Ambulatory ECG monitoring
Serum lipid profile
Cardiac enzyme assay
Pulmonary function testing

Correct Answer:
Ambulatory ECG monitoring

Explanation:
Holter or ambulatory ECG monitoring records rhythm over time and can detect episodic arrhythmias missed on a resting ECG.

MCQ 9

Question:
A patient develops ventricular ectopy after severe vomiting. Which abnormality should be corrected first because it increases myocardial electrical instability?

Options:
Hyperchloremia
Hypokalemia
Hyperphosphatemia
Hyponatremia
Hypoalbuminemia

Correct Answer:
Hypokalemia

Explanation:
Low serum potassium increases the risk of ectopy, QT-related arrhythmias and drug-induced proarrhythmia.

MCQ 10

Question:
Which class of antiarrhythmic drugs prolongs phase 3 repolarization by reducing outward potassium current?

Options:
Class IA only
Class IB
Class IC
Class II
Class III

Correct Answer:
Class III

Explanation:
Class III agents prolong repolarization, action-potential duration and refractory period through potassium-channel blockade.

MCQ 11

Question:
A patient receiving quinidine complains of tinnitus, headache and dizziness. Which adverse-effect syndrome is present?

Options:
Cinchonism
Lupus-like syndrome
Serotonin syndrome
Cholinergic crisis
Neuroleptic malignant syndrome

Correct Answer:
Cinchonism

Explanation:
Quinidine may cause cinchonism, characterized by tinnitus, headache, dizziness and visual disturbance.

MCQ 12

Question:
Which antiarrhythmic drug has prominent antimuscarinic effects and may worsen urinary retention?

Options:
Lidocaine
Disopyramide
Sotalol
Adenosine
Metoprolol

Correct Answer:
Disopyramide

Explanation:
Disopyramide is a class IA drug with marked antimuscarinic effects, including dry mouth and urinary retention.

MCQ 13

Question:
A patient with asthma develops a regular narrow-complex re-entry tachycardia. Which adverse effect makes adenosine a less suitable choice?

Options:
Severe constipation
Pulmonary fibrosis
Bronchospasm
Thyroid dysfunction
Urinary retention

Correct Answer:
Bronchospasm

Explanation:
Adenosine may provoke bronchospasm and should be used cautiously or avoided in active severe bronchospastic disease.

MCQ 14

Question:
A patient taking warfarin is started on amiodarone. Which consequence is most likely without appropriate monitoring?

Options:
Reduced anticoagulant effect
Increased bleeding tendency
Loss of AV nodal blockade
Development of hypoglycemia
Reduced serum digoxin level

Correct Answer:
Increased bleeding tendency

Explanation:
Amiodarone can increase warfarin effect, raising the INR and risk of bleeding.

MCQ 15

Question:
A patient develops nausea, yellow vision and multiple rhythm disturbances while taking digoxin. Which treatment is indicated if toxicity is life-threatening?

Options:
Glucagon
Calcium gluconate
Digoxin-specific antibody fragments
Protamine sulfate
Intravenous adenosine

Correct Answer:
Digoxin-specific antibody fragments

Explanation:
Digoxin-specific Fab fragments bind free digoxin and are used in severe toxicity with dangerous arrhythmias or hemodynamic compromise.

MCQ 16

Question:
A patient develops fever, eosinophilia and cardiac dysfunction after starting a new medication. Which type of myocarditis is most likely?

Options:
Ischemic myocarditis
Hypersensitivity myocarditis
Uremic myocarditis
Traumatic myocarditis
Degenerative myocarditis

Correct Answer:
Hypersensitivity myocarditis

Explanation:
Drug exposure with fever and eosinophilia suggests an immune-mediated hypersensitivity form of myocardial inflammation.

MCQ 17

Question:
Which imaging modality is most useful for noninvasive demonstration of myocardial edema and inflammatory injury in suspected myocarditis?

Options:
Plain chest radiography
Coronary calcium scoring
Cardiac magnetic resonance imaging
Ventilation–perfusion scanning
Abdominal ultrasonography

Correct Answer:
Cardiac magnetic resonance imaging

Explanation:
Cardiac MRI can demonstrate myocardial edema and characteristic patterns of inflammatory injury.

MCQ 18

Question:
A patient with chest pain has diffuse ST elevation, a pericardial rub and elevated troponin with mild left ventricular dysfunction. Which diagnosis best integrates these findings?

Options:
Stable angina
Isolated atrial fibrillation
Myopericarditis
Aortic dissection
Chronic constrictive pericarditis

Correct Answer:
Myopericarditis

Explanation:
Pericardial features together with myocardial injury and ventricular dysfunction indicate combined myocardial and pericardial inflammation.

MCQ 19

Question:
A patient with renal failure develops sharp positional chest pain and a pericardial rub. Which management principle addresses the underlying cause?

Options:
Increase oral anticoagulation
Optimize dialysis
Start thrombolytic therapy
Perform exercise testing
Give long-term nitrates

Correct Answer:
Optimize dialysis

Explanation:
Uremic pericarditis is treated by correcting the uremic state, commonly through initiation or intensification of dialysis.

MCQ 20

Question:
A patient has a large chronic pericardial effusion but remains hemodynamically stable. Which factor best explains the absence of tamponade?

Options:
Reduced coronary blood flow
Gradual accumulation allowing pericardial stretching
Complete absence of intrapericardial pressure
Increased myocardial contractility
Permanent closure of the venae cavae

Correct Answer:
Gradual accumulation allowing pericardial stretching

Explanation:
Slow fluid accumulation allows the pericardium to adapt and stretch, so a large volume may develop before filling becomes compromised.

📌 Important Exam Strategy

KMU examinations often test integrated understanding rather than isolated facts. Focus on linking anatomy, embryology, histology, and clinical concepts when reviewing questions.

✅ Revision Tip

If you can explain the reason behind the correct answer without looking at notes, your concept is strong.