📝 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 develops ischemia of the anterior wall of the left ventricle and anterior part of the interventricular septum. Which artery is most likely involved?
Options:
Right marginal artery
Anterior interventricular artery
Posterior interventricular artery
Circumflex artery
Small cardiac artery
Correct Answer:
Anterior interventricular artery
Explanation:
The anterior interventricular artery supplies the anterior wall of the left ventricle and anterior two-thirds of the interventricular septum.
MCQ 2
Question:
During ventricular systole, blood flow through the left coronary artery decreases mainly because of:
Options:
Closure of pulmonary valve
Compression of intramyocardial vessels
Relaxation of ventricular muscle
Opening of atrioventricular valves
Reduced aortic pressure
Correct Answer:
Compression of intramyocardial vessels
Explanation:
Left ventricular contraction compresses coronary vessels, so left coronary perfusion mainly occurs during diastole.
MCQ 3
Question:
A thrombus blocks the artery supplying the AV node in a right dominant heart. Which vessel is most commonly affected?
Options:
Circumflex artery
Left marginal artery
Right coronary artery
Anterior interventricular artery
Great cardiac vein
Correct Answer:
Right coronary artery
Explanation:
In most individuals, the AV nodal artery arises from the right coronary artery.
MCQ 4
Question:
A surgeon passes a finger through the transverse pericardial sinus. The finger passes posterior to which structure?
Options:
Superior vena cava
Left atrium
Ascending aorta
Inferior vena cava
Pulmonary veins
Correct Answer:
Ascending aorta
Explanation:
The transverse pericardial sinus lies posterior to the ascending aorta and pulmonary trunk and anterior to the superior vena cava.
MCQ 5
Question:
A sudden occlusion of a coronary artery causes infarction despite small arterial connections. This is because coronary arteries are functionally:
Options:
Elastic arteries
End arteries
Portal vessels
Venous sinusoids
Lymphatic channels
Correct Answer:
End arteries
Explanation:
Coronary anastomoses are usually insufficient during sudden blockage, so coronary arteries behave as functional end arteries.
MCQ 6
Question:
Most venous blood from the myocardium returns to the right atrium through the:
Options:
Anterior cardiac veins
Coronary sinus
Pulmonary veins
Superior vena cava
Thebesian veins
Correct Answer:
Coronary sinus
Explanation:
The coronary sinus is the main venous channel draining most cardiac veins into the right atrium.
MCQ 7
Question:
The great cardiac vein is expected to accompany which artery?
Options:
Right marginal artery
Posterior interventricular artery
Anterior interventricular artery
SA nodal artery
AV nodal artery
Correct Answer:
Anterior interventricular artery
Explanation:
The great cardiac vein accompanies the anterior interventricular artery in the anterior interventricular groove.
MCQ 8
Question:
A patient with rapid fluid accumulation in the pericardial cavity develops hypotension. The immediate physiological cause is reduced:
Options:
Ventricular filling
Aortic elasticity
Pulmonary diffusion
Valve calcification
Myocardial oxygen use
Correct Answer:
Ventricular filling
Explanation:
Cardiac tamponade compresses the heart externally and restricts ventricular filling, reducing cardiac output.
MCQ 9
Question:
The fibrous pericardium mainly helps the heart by:
Options:
Increasing myocardial contraction
Preventing excessive cardiac dilation
Producing cardiac impulse
Draining venous blood
Opening coronary arteries
Correct Answer:
Preventing excessive cardiac dilation
Explanation:
The tough fibrous pericardium stabilizes the heart and limits sudden overdistension.
MCQ 10
Question:
Atherosclerotic plaque rupture in a coronary artery most directly leads to:
Options:
Valve stenosis
Platelet aggregation
Pericardial adhesion
Venous reflux
Lymphatic blockage
Correct Answer:
Platelet aggregation
Explanation:
Plaque rupture exposes thrombogenic material, causing platelet adhesion, aggregation, and thrombus formation.
MCQ 11
Question:
The left circumflex artery mainly runs in which anatomical groove?
Options:
Anterior interventricular groove
Posterior interventricular groove
Left atrioventricular groove
Right atrioventricular groove
Interatrial groove
Correct Answer:
Left atrioventricular groove
Explanation:
The circumflex branch of the left coronary artery courses in the left part of the coronary sulcus.
MCQ 12
Question:
A blockage of the posterior interventricular artery is most likely to affect which region?
Options:
Posterior part of interventricular septum
Anterior wall of right atrium
Apex only
Pulmonary trunk wall
Left auricle only
Correct Answer:
Posterior part of interventricular septum
Explanation:
The posterior interventricular artery supplies the posterior one-third of the interventricular septum.
MCQ 13
Question:
The visceral layer of serous pericardium is also known as:
Options:
Endocardium
Myocardium
Epicardium
Fibrous capsule
Mediastinal pleura
Correct Answer:
Epicardium
Explanation:
The visceral serous pericardium is closely adherent to the heart surface and forms the epicardium.
MCQ 14
Question:
Coronary flow increases during exercise mainly due to accumulation of:
Options:
Metabolic vasodilators
Bile pigments
Plasma proteins
Calcium salts
Digestive enzymes
Correct Answer:
Metabolic vasodilators
Explanation:
Active myocardium releases metabolites such as adenosine, hydrogen ions, and carbon dioxide, causing coronary vasodilation.
MCQ 15
Question:
A sharp chest pain that worsens with breathing and is associated with a friction rub suggests:
Options:
Myocardial hypertrophy
Pericarditis
Aortic stenosis
Mitral prolapse
Pulmonary edema
Correct Answer:
Pericarditis
Explanation:
Pericarditis causes inflamed pericardial surfaces to rub against each other, producing pleuritic chest pain and friction rub.
MCQ 16
Question:
Which vessel enters the pericardial sac to reach the right atrium?
Options:
Pulmonary trunk
Ascending aorta
Superior vena cava
Left coronary artery
Right pulmonary artery
Correct Answer:
Superior vena cava
Explanation:
The superior vena cava enters the pericardium and opens into the right atrium.
MCQ 17
Question:
Lymph from the heart primarily follows coronary vessels and drains toward:
Options:
Tracheobronchial lymph nodes
Inguinal lymph nodes
Celiac lymph nodes
Axillary lymph nodes
Submental lymph nodes
Correct Answer:
Tracheobronchial lymph nodes
Explanation:
Cardiac lymphatics accompany coronary vessels and mainly drain into tracheobronchial lymph nodes.
MCQ 18
Question:
A reduction in diastolic pressure is most likely to compromise:
Options:
Coronary perfusion
Venous valve closure
Pericardial fluid secretion
Pulmonary surfactant release
Atrial septal formation
Correct Answer:
Coronary perfusion
Explanation:
Coronary arteries, especially the left coronary system, are mainly perfused during diastole.
MCQ 19
Question:
A thrombus in the right marginal branch most directly affects blood supply to the:
Options:
Right ventricular margin
Left atrial roof
Anterior septum
Left ventricular apex
Pulmonary valve cusp
Correct Answer:
Right ventricular margin
Explanation:
The right marginal artery supplies the inferior margin and adjacent wall of the right ventricle.
MCQ 20
Question:
The oblique pericardial sinus is located mainly behind the:
Options:
Right ventricle
Left atrium
Pulmonary trunk
Ascending aorta
Superior vena cava
Correct Answer:
Left atrium
Explanation:
The oblique pericardial sinus is a blind recess of pericardial cavity situated posterior to the left atrium.
📌 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.