📝 Step 6 — 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 severe hypertension develops left ventricular hypertrophy. Which change is most directly responsible for increased myocardial workload in this patient?
Options:
Reduced venous tone
Increased peripheral resistance
Decreased ventricular preload
Reduced arterial compliance
Increased pulmonary pressure
Correct Answer:
Increased peripheral resistance
Explanation:
Hypertension increases afterload by increasing peripheral resistance, forcing the left ventricle to generate higher pressure during systole.
MCQ 2
Question:
During ventricular systole, the volume of blood remaining in the ventricle after ejection is called:
Options:
Stroke volume
Residual capacity
End-diastolic volume
Cardiac reserve
End-systolic volume
Correct Answer:
End-systolic volume
Explanation:
End-systolic volume is the blood left in the ventricle after ventricular contraction is complete.
MCQ 3
Question:
A patient with myocardial ischemia develops reduced cardiac contractility. Which cellular event is most directly impaired?
Options:
Potassium influx into sarcolemma
Calcium-mediated actin-myosin interaction
Sodium diffusion through gap junctions
Chloride transport across T-tubules
Phosphate movement through intercalated discs
Correct Answer:
Calcium-mediated actin-myosin interaction
Explanation:
Cardiac contraction depends on intracellular calcium binding to troponin, allowing actin-myosin cross-bridge formation.
MCQ 4
Question:
A sudden increase in venous return during exercise increases stroke volume primarily through:
Options:
Reduced arterial pressure
Enhanced vagal discharge
Frank-Starling mechanism
Closure of semilunar valves
Reduced myocardial oxygen demand
Correct Answer:
Frank-Starling mechanism
Explanation:
Increased venous return stretches ventricular muscle fibers, producing stronger contraction and greater stroke volume.
MCQ 5
Question:
A patient with left-sided heart failure presents with breathlessness. Which mechanism best explains this symptom?
Options:
Reduced systemic venous return
Fluid accumulation in alveolar tissue
Increased skeletal muscle activity
Reduced hepatic circulation
Peripheral lymphatic obstruction
Correct Answer:
Fluid accumulation in alveolar tissue
Explanation:
Left ventricular failure causes pulmonary venous congestion, leading to pulmonary edema and impaired gas exchange.
MCQ 6
Question:
Which feature of cardiac muscle allows coordinated ventricular contraction?
Options:
Dense connective tissue septa
Elastic recoil fibers
Gap junctions within intercalated discs
Keratinized cellular junctions
Fibrocartilaginous support bands
Correct Answer:
Gap junctions within intercalated discs
Explanation:
Gap junctions allow rapid spread of electrical impulses between cardiac muscle cells for synchronized contraction.
MCQ 7
Question:
A decrease in ATP production within cardiac muscle cells would most directly impair:
Options:
Pulmonary diffusion capacity
Cross-bridge cycling during contraction
Venous valve competence
Arterial elastic recoil
Coronary venous drainage
Correct Answer:
Cross-bridge cycling during contraction
Explanation:
ATP is essential for actin-myosin interaction and calcium reuptake during contraction-relaxation cycles.
MCQ 8
Question:
During dynamic exercise, increased cardiac output is mainly achieved by:
Options:
Reduced sympathetic activity
Decreased venous return
Increased heart rate and stroke volume
Reduced myocardial contractility
Closure of arteriovenous shunts
Correct Answer:
Increased heart rate and stroke volume
Explanation:
Exercise increases sympathetic stimulation, raising both heart rate and stroke volume.
MCQ 9
Question:
Which pressure-volume loop change is most likely seen in systolic heart failure?
Options:
Reduced end-systolic volume
Increased ejection fraction
Increased stroke volume
Reduced ventricular compliance
Increased end-systolic volume
Correct Answer:
Increased end-systolic volume
Explanation:
Reduced ventricular contractility prevents efficient ejection, leaving more blood after systole.
MCQ 10
Question:
A patient with severe dehydration develops low cardiac output. Which initial hemodynamic change is most likely responsible?
Options:
Reduced myocardial ATPase activity
Reduced venous return
Increased systemic resistance
Reduced pulmonary ventilation
Increased ventricular compliance
Correct Answer:
Reduced venous return
Explanation:
Loss of blood volume decreases venous return, reducing preload and stroke volume.
MCQ 11
Question:
The systolic work output of the ventricle is represented on the pressure-volume loop by:
Options:
Slope of ventricular filling line
Width of isovolumetric phase
Area enclosed within the loop
Length of ventricular relaxation phase
Height of atrial contraction wave
Correct Answer:
Area enclosed within the loop
Explanation:
The area inside the pressure-volume loop represents ventricular external work during one cardiac cycle.
MCQ 12
Question:
Which factor most directly increases venous return during inspiration?
Options:
Rise in intra-abdominal pressure
Increase in thoracic pressure
Reduction in intrathoracic pressure
Closure of venous valves
Decrease in atrial compliance
Correct Answer:
Reduction in intrathoracic pressure
Explanation:
Inspiration lowers intrathoracic pressure, drawing venous blood toward the heart.
MCQ 13
Question:
A patient with right-sided heart failure is most likely to develop:
Options:
Pulmonary fibrosis
Peripheral edema
Mitral valve stenosis
Pulmonary hemorrhage
Systemic hypotension only
Correct Answer:
Peripheral edema
Explanation:
Right ventricular failure causes systemic venous congestion leading to dependent edema.
MCQ 14
Question:
Which physiological change most directly improves ejection fraction?
Options:
Reduced myocardial contractility
Increased ventricular afterload
Enhanced calcium availability
Reduced ventricular filling
Increased peripheral resistance
Correct Answer:
Enhanced calcium availability
Explanation:
Greater intracellular calcium improves contractile force and increases ventricular ejection.
MCQ 15
Question:
A patient with chronic anemia develops high-output cardiac failure because:
Options:
Blood viscosity markedly increases
Tissue oxygen delivery decreases
Pulmonary resistance rises sharply
Myocardial fibrosis develops early
Arterial compliance decreases completely
Correct Answer:
Tissue oxygen delivery decreases
Explanation:
Reduced oxygen-carrying capacity causes compensatory increase in cardiac output to maintain tissue oxygenation.
MCQ 16
Question:
Which vessel type contributes most to total peripheral resistance?
Options:
Elastic arteries
Muscular arteries
Arterioles
Capillaries
Venules
Correct Answer:
Arterioles
Explanation:
Arterioles are resistance vessels with adjustable smooth muscle tone controlling systemic resistance.
MCQ 17
Question:
A reduction in SERCA pump activity would most likely impair:
Options:
Cardiac muscle relaxation
Pulmonary capillary diffusion
Venous blood storage
Aortic valve opening
Coronary artery perfusion
Correct Answer:
Cardiac muscle relaxation
Explanation:
SERCA pumps return calcium to the sarcoplasmic reticulum, enabling myocardial relaxation.
MCQ 18
Question:
A patient with severe left ventricular dysfunction develops pulmonary edema. Which Starling force change primarily causes fluid movement into alveoli?
Options:
Reduced capillary hydrostatic pressure
Increased plasma oncotic pressure
Increased pulmonary capillary hydrostatic pressure
Reduced interstitial fluid pressure
Increased lymphatic osmotic pressure
Correct Answer:
Increased pulmonary capillary hydrostatic pressure
Explanation:
Left ventricular failure elevates pulmonary venous pressure, increasing capillary hydrostatic pressure and fluid filtration.
MCQ 19
Question:
Which change occurs first when venous return suddenly increases in a healthy individual?
Options:
Peripheral resistance decreases
End-diastolic volume rises
Ejection fraction falls
Afterload decreases
Myocardial oxygen extraction falls
Correct Answer:
End-diastolic volume rises
Explanation:
Increased venous return first increases ventricular filling and preload.
MCQ 20
Question:
Which mechanism best explains fatigue in chronic heart failure?
Options:
Reduced pulmonary surfactant synthesis
Impaired skeletal muscle perfusion
Excessive lymphatic drainage
Increased venous compliance
Reduced coronary venous return
Correct Answer:
Impaired skeletal muscle perfusion
Explanation:
Reduced cardiac output decreases oxygen delivery to skeletal muscles, causing weakness and fatigue.
📌 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.