📝 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 patient with coronary artery disease develops chest discomfort when tachycardia occurs during emotional stress. Which physiological change most directly worsens myocardial perfusion in this situation?

Options:
Increased right atrial filling time
Reduced systemic vascular resistance
Shortened diastolic coronary filling time
Reduced pulmonary arterial pressure
Increased venous oxygen saturation

Correct Answer:
Shortened diastolic coronary filling time

Explanation:
Left coronary perfusion occurs mainly during diastole. Tachycardia shortens diastole, reducing coronary filling time and worsening ischemia.

MCQ 2

Question:
During gross examination of the heart, a valve is seen at the outlet of the left ventricle. It has three semilunar cusps and no chordae tendineae. Which valve is being described?

Options:
Aortic valve
Mitral valve
Tricuspid valve
Pulmonary valve
Coronary valve

Correct Answer:
Aortic valve

Explanation:
The aortic valve is a semilunar valve located between the left ventricle and ascending aorta. Semilunar valves have three cusps and lack chordae tendineae.

MCQ 3

Question:
Atherosclerotic narrowing of a coronary artery does not produce chest pain at rest but produces pain during exertion. Which concept best explains this finding?

Options:
Increased pulmonary venous drainage
Reduced atrial electrical activity
Increased myocardial glycogen storage
Reduced coronary flow reserve
Reduced valve leaflet movement

Correct Answer:
Reduced coronary flow reserve

Explanation:
At rest, narrowed coronary arteries may provide enough blood. During exertion, they cannot dilate enough to meet increased oxygen demand.

MCQ 4

Question:
A patient has chest pain due to transient myocardial ischemia. Which cellular metabolic change occurs early before irreversible injury develops?

Options:
Excessive collagen deposition
Reduced ATP generation
Permanent sarcomere loss
Granulation tissue formation
Dense fibrous scar formation

Correct Answer:
Reduced ATP generation

Explanation:
Ischemia decreases oxygen delivery, reducing aerobic ATP production. If ischemia persists, irreversible injury and infarction may occur.

MCQ 5

Question:
A man dies after prolonged coronary occlusion. Microscopy of the affected myocardium shows preserved tissue outline with dead cardiac muscle cells. Which pattern of necrosis is most likely?

Options:
Caseous necrosis
Liquefactive necrosis
Fat necrosis
Fibrinoid necrosis
Coagulative necrosis

Correct Answer:
Coagulative necrosis

Explanation:
Myocardial infarction classically produces coagulative necrosis, where the basic tissue architecture is initially preserved.

MCQ 6

Question:
In a patient with chronic stable angina, long-term treatment includes drugs that reduce future coronary events, not only drugs that relieve pain. Which management component is most relevant to this aim?

Options:
Risk factor control with antiplatelet and lipid-lowering therapy
Routine opioid use before exertion
High-dose nitrate without interruption
Avoidance of all physical activity
Immediate thrombolysis for every episode

Correct Answer:
Risk factor control with antiplatelet and lipid-lowering therapy

Explanation:
Stable angina management includes symptom relief plus prevention of infarction through risk factor control, antiplatelet therapy, and lipid lowering where indicated.

MCQ 7

Question:
A patient with exertional angina has a normal resting ECG. Which investigation is more likely to reveal inducible ischemia in this patient?

Options:
Resting chest radiograph
Serum urea estimation
Plain abdominal ultrasound
Exercise stress ECG
Routine urine microscopy

Correct Answer:
Exercise stress ECG

Explanation:
Resting ECG may be normal in stable angina. Stress testing can reveal ischemic changes when myocardial oxygen demand is increased.

MCQ 8

Question:
A man with variant angina is treated with a drug that inhibits L-type calcium channels in vascular smooth muscle. Which effect explains its benefit?

Options:
Increased platelet aggregation
Reduced coronary arterial spasm
Increased myocardial sodium entry
Enhanced AV nodal discharge
Reduced nitrate bioavailability

Correct Answer:
Reduced coronary arterial spasm

Explanation:
Calcium channel blockers relax coronary smooth muscle, making them especially useful in vasospastic angina.

MCQ 9

Question:
A patient taking short-acting nifedipine develops flushing, headache, and palpitation. Which mechanism best explains the palpitation?

Options:
Direct SA node blockade
Reduced catecholamine release
Increased AV nodal inhibition
Direct myocardial depression
Reflex sympathetic activation

Correct Answer:
Reflex sympathetic activation

Explanation:
Dihydropyridine calcium channel blockers cause vasodilation. Rapid vasodilation may trigger reflex tachycardia.

MCQ 10

Question:
A patient with angina is given sublingual nitroglycerin instead of swallowing the tablet. What is the main reason for this route?

Options:
Improved renal elimination
Reduced gastric irritation
Avoidance of first-pass metabolism
Increased intestinal absorption
Reduced pulmonary clearance

Correct Answer:
Avoidance of first-pass metabolism

Explanation:
Nitroglycerin undergoes significant hepatic first-pass metabolism. Sublingual administration gives rapid systemic absorption.

MCQ 11

Question:
An antianginal drug increases cGMP in vascular smooth muscle. Which vascular effect is most responsible for reducing myocardial oxygen demand?

Options:
Venodilation with reduced preload
Arteriolar constriction with increased afterload
Pulmonary vasoconstriction with hypoxia
Coronary thrombosis with ischemic preconditioning
Increased ventricular filling pressure

Correct Answer:
Venodilation with reduced preload

Explanation:
Organic nitrates increase nitric oxide and cGMP, causing venodilation. Reduced preload lowers ventricular wall tension and oxygen demand.

MCQ 12

Question:
A patient with chronic stable angina and bronchial asthma requires long-term antianginal therapy. Which drug choice needs extra caution due to risk of bronchospasm?

Options:
Isosorbide mononitrate
Amlodipine
Ranolazine
Propranolol
Nitroglycerin

Correct Answer:
Propranolol

Explanation:
Nonselective β-blockers can block β2 receptors in bronchi and may worsen bronchospasm in asthmatic patients.

MCQ 13

Question:
A patient with stable angina is already hypotensive, so further reduction in blood pressure is undesirable. Which antianginal drug is useful because it has minimal effect on heart rate and blood pressure?

Options:
Nifedipine
Ranolazine
Nitroglycerin
Verapamil
Propranolol

Correct Answer:
Ranolazine

Explanation:
Ranolazine reduces angina by inhibiting late sodium current and improving myocardial relaxation, with little effect on heart rate or blood pressure.

MCQ 14

Question:
A man with recurrent chest pain at rest has angiography showing no major fixed coronary obstruction. During pain, transient ST elevation is recorded. Which drug group is most appropriate for prevention?

Options:
Loop diuretics
Cardiac glycosides
Oral anticoagulants alone
β-blockers as sole therapy
Calcium channel blockers

Correct Answer:
Calcium channel blockers

Explanation:
Rest angina with transient ST elevation and normal angiography suggests coronary vasospasm. Calcium channel blockers prevent spasm.

MCQ 15

Question:
Which change best separates infarction from reversible ischemia in a patient with coronary artery disease?

Options:
Temporary chest discomfort
Relief of pain by rest
Myocyte membrane disruption
Increased cardiac workload
Normal serum biomarkers

Correct Answer:
Myocyte membrane disruption

Explanation:
Infarction involves irreversible injury with membrane damage and leakage of cardiac biomarkers. Reversible ischemia does not cause necrosis.

MCQ 16

Question:
A patient has exertional angina due to increased myocardial oxygen demand. Which hemodynamic factor directly increases ventricular wall stress and oxygen requirement?

Options:
Elevated arterial pressure
Reduced venous oxygen level
Reduced blood glucose level
Increased lung compliance
Reduced atrial conduction

Correct Answer:
Elevated arterial pressure

Explanation:
High arterial pressure increases afterload and ventricular wall stress, thereby increasing myocardial oxygen demand.

MCQ 17

Question:
A patient with ischemic heart disease develops sudden death before reaching hospital. Which mechanism is a common immediate cause in ischemic heart disease?

Options:
Acute pleural effusion
Progressive liver failure
Gastric outlet obstruction
Fatal cardiac arrhythmia
Pulmonary valve calcification

Correct Answer:
Fatal cardiac arrhythmia

Explanation:
Ischemic myocardium is electrically unstable. Ventricular arrhythmias are a major cause of sudden cardiac death in ischemic heart disease.

MCQ 18

Question:
A patient with stable angina is started on verapamil. Which additional drug combination can increase the risk of severe bradycardia and AV block?

Options:
Sublingual nitrate
β-adrenergic blocker
Low-dose aspirin
Statin therapy
Oral antacid

Correct Answer:
β-adrenergic blocker

Explanation:
Verapamil depresses AV nodal conduction. Combining it with β-blockers can produce marked bradycardia and AV block.

MCQ 19

Question:
A coronary plaque narrows the lumen gradually over years. Which clinical pattern is most consistent with this pathology?

Options:
Pain only after blunt chest trauma
Sharp pleuritic pain with fever
Sudden tearing interscapular pain
Palpitation without exertional symptoms
Predictable pain during fixed workload

Correct Answer:
Predictable pain during fixed workload

Explanation:
Stable fixed coronary narrowing produces predictable ischemia when myocardial oxygen demand reaches a certain level.

MCQ 20

Question:
A student confuses organic nitrate action with β-blocker action. Which statement correctly matches the main antianginal mechanism?

Options:
Nitrates reduce heart rate through SA node blockade
β-blockers reduce preload through venodilation
Nitrates reduce preload through venodilation
β-blockers relax coronary spasm through cGMP
Nitrates inhibit late sodium current in myocardium

Correct Answer:
Nitrates reduce preload through venodilation

Explanation:
Nitrates mainly reduce preload by venodilation. β-blockers reduce oxygen demand mainly by lowering heart rate and contractility.

📌 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.