sample questions

Question 1

Answer 1

D. SA nodal discharge rate is controlled either directly or indirectly through the autonomic nervous system. All in the list increases heart rate except parasympathetic activation.

Question 2

Answer 2

B. The AV node has the slowest rate of conduction. It is the gatekeeper for electrical signals going downstream into the ventricles. The slow rate of conduction allows the atria to be depolarised and begin contracting before the ventricles are depolarised and contract. Hence, the atria act as “priming” pumps for the ventricles.

Question 3

Answer 3

C. The entry of calcium during this phase of the action potential balances the outgoing potassium ion, hence the “plateau” phase. The calcium entering the cell at this time is critical for subsequent ventricular muscle contraction.

Question 4

Answer 4

A,E. The AV fibrous ring isolates the atria and ventricles electrically. Hence the only place that allows electrical signals to travel from the atria into the ventricles is the AV node. The delay at the AV node delays the depolarisation of the ventricles. This allows the atria to pump before the ventricles, hence the “priming” function of the atria.

Question 5

Answer 5

B. A patient with transplanted heart will not have autonomic innervation of the SA node. Hence the heart rate can only be regulated by factors that act directly on the SA node, blood temperature being one of them, hence fever. Exercise will increase the heart rate through the direct action of epinephrine and temperature. Resting heart rate will be faster than normal since the basal heart rate is influenced by parasympathetic innervation. Sinus arrhythmia will no longer be present because it is dependent on the presence of a functioning autonomic nervous system.

Question 6

Answer 6

B,C,D. Complete heart block means there is no transmission of electrical signals from the atria into the ventricles. The atria and ventricles function independent of each other. Heart rate (due to ventricular contractions) will decrease because the ventricular rate is no longer controlled by the SA node, but by a pacemaker downstream of the AV node, which discharges at a slower rate. Atrial contraction rate is normal because it is still controlled by the SA node. Ventricular stroke volume is variable because filling is variable, since the atria and ventricles are no longer coordinated.

Question 7

Answer 7

C. In a regular ECG recording, the paper is run at a speed of 25 mm/s, hence each mm (small square on the ECG) is 0.04s. A big square on the ECG paper is 5 small squares, hence 0.2s.

Question 8

Answer 8

B. The PR interval is the time taken for the electrical signal to travel from the SA node to the AV node, “traverse” the AV node, until it is just into the Bundle of His. The bulk of this time is “traversing” the AV node, because conduction is slow. A slower conduction through the AV node will result in the prolongation of the PR interval.

Question 9

Answer 9

A. Positive R wavs in lead I locates the electrical axis in the right half of the “circle”. Positive R waves in aVF locates the axis in the bottom half of the circle. Where they intersect is in the quadrant between 0 – 90o, hence the electrical axis is normal.

Question 10

Answer 10

D. QT is the interval from the beginning of the Q wave to the end of the T wave. Q is ventricular depolarisation, T is ventricular repolarisation. Hence, the QT interval is the time taken both ventricular depolarisation and repolarisation.

Question 11

Answer 11

A. AV nodal delay will cause a prolongation of the PR interval.

Question 12

Answer 12

E. Leads II, III and aVF are contiguous leads and look at the inferior part of the heart (both R and L ventricle). The precordial chest leads, Lead I and Lead aVL look at the anterior part of the left ventricle.

Question 13

Answer 13

E. aVL is the reciprocal lead for the inferior part of the heart. ST segment depression in this lead is often the first sign of an inferior myocardial infarction.

Question 14

Answer 14

A. Digoxin inhibits the Na-K ATPase resulting in a decrease in sodium gradient across the cell membrane. This indirectly affects the function of the Na/Ca exchanger, resulting in retention of calcium within the cell, and hence stronger contractions.

Question 15

Answer 15

D. Blood is ejected into the aorta during ventricular systole. The other events occur during diastole.

Question 16

Answer 16

C. EF = EDV-ESV/EDV. 150-60/150 = 0.6

Question 17

Answer 17

A. The aortic valve opens at the end of isovolumetric contraction, after pressure has built up in the ventricles. The aortic valve closes at the beginning of diastole, not end of diastole. Closure of the aortic valve gives rise to the second heart sound, not first. The second heart sound is due to the closure of the aortic valve, and occurs after atrial contraction, not during. The 4th heart sound occurs during late diastole, not early diastole.

Question 18

Answer 18

D. The third heart sound may occur during early diastole, not in the other phases listed.

Question 19

Answer 19

A

Question 20

Answer 20

D. Drop in heamatocrit reduces blood viscosity level, resistance drop, dia drop

Question 21

What part corresponds to ventricular systole

Answer 21

Start of R to end of T wave

Question 22

Does phrenic nerve regulate heart rate?

Answer 22

No. The phrenic nerve does not supply motor innervation to the heart. However, it does have sensory components for the fibrous pericardium.

Question 23

Which of the following statements is FALSE about the autonomic innervation of the heart?
a. At the preganglionic synapse for parasympathetic innervation, acetylcholine is released from the preganglionic neuron
b. At the postganglionic synapse for parasympathetic innervation, acetylcholine is released from the postganglionic neuron
c. At the postganglionic synapse for sympathetic innervation, noradrenaline (norepinephrine) is released from the postganglionic neuron
d. Postganglionic neurons are located in cervical ganglia
e. Postganglionic neurons run in the vagus nerve

Answer 23

E. Preganglionic neurons, with cell bodies in the dorsal vagal motor nucleus in the brainstem, run in the vagus nerve to synapse onto postganglionic neurons, with cell bodies in autonomic ganglia near the organ of innervation (in this case, the heart). The post ganglionic neuron then runs for a short distance directly to the heart.

Question 24

Ivabradine is a drug that inhibits the “funny” channels in the sinuatrial node of the heart. Which of the following is an effect of Ivabradine?
a. Increase heart rate
b. Decrease heart rate
c. Increase contractility of the heart
d. Decrease contractility of the heart
e. Increases duration of the QRS segment (i.e. prolonged QRS) of the ECG

Answer 24

Option B: The “funny” channels in the sinuatrial node of the heart allow for an inward Na+ current that results in a slow spontaneous depolarization, which allows for the SA nodal cells to spontaneously generate action potentials (when the depolarization eventually reaches threshold) without neural input. When ivabradine blocks these channels, there is a decrease in “funny” current and a slower rate of depolarization, which translates to a slower heart rate.

Question 25

The following would be observed in a patient in hypovolemic shock except:
a. Sweating (increased sympathetic innervation)
b. Decreased urine output (ADH / aldosterone)
c. Higher central venous pressure
d. Increased plasma aldosterone concentration
e. Increased total peripheral resistance

Answer 25

Option C: Central venous pressure is a reflection of the preload and venous return. Since the patient is hypovolemic, central venous pressure is expected to be low.

Question 26

10. If there is a blockage between the AV node and the AV bundle, how will this affect the appearance of the EKG?
    a. PR interval would be smaller
    b. QRS interval would be shorter
    c. There would be more P waves than QRS complexes
    d. There would be more QRS complexes than P waves
    e. The T wave would be absent

Answer 26

Option C: P waves are due to atrial depolarization as a result of sinuatrial node firing. However, since impulses from the sinuatrial node cannot get to the ventricles, ventricular depolarization depends on pacemaker activity of the Purkinje fibres, which fire at a much slower rate than sinuatrial node. Hence, QRS complexes will appear less frequently than P waves.

Question 27

According to the Frank-Starling Law of the heart, CO is directly related to:
a. Ventricular muscle mass
b. Heart rate
c. Amount of blood returning to the heart
d. ESV
e. Cardiac reserve

Answer 27

Option C: According to the Frank-Starling law, the volume of blood ejected by the ventricle depends on the volume present in the ventricle at the end of diastole (venous return).

Question 28

13. The T wave on an ECG represents:
    a. Ventricular depolarization
    b. Ventricular repolarization
    c. Atrial depolarization
    d. Atrial repolarization
    e. Ventricular systole

Answer 28

Option B.

Question 29

Do blood vessels have d. Parasympathetic stimulation?

Answer 29

No

Question 30

Which of the following depolarizes next after the AV node:
a. Atrial myocardium
b. Ventricular myocardium
c. Bundle branches
d. Purkinje fibers

Answer 30

Option C: The electrical impulse from the AV node spreads to the bundle of His, then right and left bundle branches, then Purkinje fibres before the ventricular myocardium.

Question 31

The statement “strength of contraction increases intrinsically due to increased stretching of the heart wall” is best attributed to:
a. Poiusseille’s law
b. Bainbridge reflex
c. Frank-Starling law
d. Faraday’s law
e. Henry’s law

Answer 31

C

Question 32

Which of the following descriptions of ECG leads V1 to V6 is true?
a. They are unipolar leads measuring electric potential in the frontal plane
b. They are unipolar leads measuring electric potential in the horizontal plane
c. They are bipolar leads measuring electric potential in the frontal plane
d. They are bipolar leads measuring electric potential in the horizontal plane
e. They are bipolar leads measuring electric potential in both frontal and horizontal planes

Answer 32

Option B: Precordial leads (V1 to V6) are unipolar leads. They measure electric potential in the horizontal (transverse) plane. They are the only leads used to measure the heart’s electrical axis in the transverse plane.

Question 33

During the cardiac cycle,
a. Heart sounds are caused by the opening of valves
b. The 4th heart sound is caused by atrial filling
c. The pressures in the LV and aorta are equal
d. Ventricular ejection of blood occurs during the entire duration of systole
e. Closure of the mitral valve marks the beginning of systole

Answer 33

E.
Option D: Systole has two components, isovolumetric contraction and the actual ejection of blood. In isovolumetric contraction, the ventricle contracts when heart valves are closed, building up pressure.
Option E: The closure of the mitral valve (atrioventricular valve) marks the start of systole, specifically the start of isovolumetric contraction.

Question 34

A young man complains of cold and pain in his fingers in an air-conditioned room. Which of the following most likely accounts for the increased sensitivity to cold?
a. Low concentrations of circulating epinephrine
b. Low concentrations of circulating norepinephrine
c. High sensitivity of arterioles to norepinephrine
d. High sensitivity of arterioles to nitric oxide
e. Decreased parasympathetic stimulation to arterioles in the skin

Answer 34

C.

Option C: High sensitivity of arterioles to norepinephrine would result in vasoconstriction that decreases blood flow to his fingers, causing pain and cold.

Question 35

42. Total peripheral resistance decreases during exercise because of the effect of:
    A. parasympathetic stimulation to skeletal muscles
    B. local metabolites on skeletal muscle arterioles
    C. increase in cardiac output
    D. increase in blood pressure
    E. histamine on skeletal muscle arterioles

Answer 35

B. When blood flow is insufficient relative to metabolic demand, metabolites such as adenosine and hydrogen ions accumulate in the myocardial tissues, leading to the release of NO, which causes vasodilation.

Question 36

In myocardial infarction:
a) The infarcted area is visible to the naked eye (macroscopically) immediately after the onset of infarction
b) Microscopic changes appear after 12 hours
c) The infarcted area is soft after 4 weeks
d) Neutrophilic infiltration in an infarct occurs immediately within 1 hour
e) The infarcted area is replaced by scar tissue in one week

Answer 36

B

Question 37

Mitral stenosis is associated with all of the following, EXCEPT:
a) Rheumatic fever
b) Atrial fibrillation
c) Pulmonary hypertension
d) Mitral valves prolapse
e) Failure of the mitral valve to open completely

Answer 37

D. Mitral valves prolapse = ballooning of valvular cusps, affected leaflets thickened & rubbery, myxoid degeneration of leaflet, rupture of chordinae tendinae results in mitral regurgitation. Risk factors: Young women, Marfan’s syndrome.

Question 38

Which of the following is true about a dissecting aneurysm of the aorta?
a) It is usually clinically silent
b) The common site of tear is at the abdominal aorta above the bifurcation
c) It is due to atherosclerosis
d) It is associated with medial degeneration of elastic tissue and mucopolysaccharide deposition
e) It resolves spontaneously

Answer 38

d. separation between intima and media

Question 39

A patient presented with fever, chills, malaise, and blood in the urine. He was found to have a cardiac murmur and nail-bed hemorrhages; ECG revealed valvular vegetations. The most likely diagnosis is:
a) Rheumatic Heart Disease
b) MV prolapse
c) MI
d) Infective endocarditis
e) Myocardial hypertrophy

Answer 39

D

Question 40

Which of the following statements is false about dissecting aneurysm?
a) It is not characteristic of hypertension
b) Blood enters the arterial wall and forms a haematoma
c) it is commonly seen in young patients with marfan’s syndrome
d) there is weakening of smooth muscle and elastic tissue in the tunica media
e) Death due to rupture

Answer 40

A

Question 41

RV failure leads to:
a) Pulmonary hypertension
b) Peritoneal effusion
c) Pulmonary oedema
d) Lowered CVP
e) RV infarction

Answer 41

B

Question 42

A patient has been taking digitalis as treatment for heart failure. Digitalis can cause AV nodal delay and shortens ventricular repolarization. Which of the following changes may be observed in the patient’s ECG?
A. Shortened PR interval
B. Shortened QT interval
C. Increased heart rate
D. Prolonged QRS interval
E. Prominent T waves

Answer 42

B. QT interval is the time between the start of the Q wave and end of the T wave. It represents ventricular depolarization and repolarisation. Since ventricular repolarisation is shortened, T wave is shorted and QT interval would be shortened

Question 43

Oedema may occur in all of the following EXCEPT
A. decreased plasma protein concentration
B. increased capillary permeability
C. decreased venous pressure
D. increased capillary pressure
E. obstruction to lymph flow

Answer 43

C. Decreased plasma protein concentration would decrease capillary oncotic pressure and reduce absorption. Hence, fluid movement favours filtration and edema can develop if the lymphatic system is not able to remove the excess fluid.

Decreased venous pressure reduces capillary hydrostatic pressure, reducing net filtration. Edema is not likely to occur in such cases.

Question 44

Too fast heart rates can influence blood supply to the heart. Which of the following may occur under these circumstances?
A. Perfusion of LV greater than LA
B. Perfusion of LV greater than RV
C. Perfusion of RV greater than LV
D. No difference in perfusion between LV and RV
E. Perfusion of RA less than LA

Answer 44

Option C: Blood flows through the left coronary artery during diastole while blood flows through the right coronary artery during both diastole and systole. When heart rate increases, in the time taken for one heartbeat, the length of systole remains approximately constant while diastole time decreases significantly in comparison. Hence, left coronary blood flow is compromised and perfusion of left ventricle decreases more as compared to that for the right ventricle.

Question 45

Elderly patients with atherosclerosis of blood vessels, where elasticity is lost may be expected to have diastolic pressures
A. higher than normal
B. Same as systolic pressure
C. Less than normal
D. That are normal

Answer 45

Option C: Elderly patients with atherosclerosis of blood vessels usually have isolated systolic hypertension, where systolic blood pressure is above 140 while diastolic pressure stays below 90. This is due to loss of elasticity and increased stiffness of arteries.

Question 46

A first year medical student is given an ECG tracing for the first time. He tries to determine a point on the tracing where the ventricles are completely depolarized. He thinks it would be at the start of the P wave. His answer is obviously wrong. What do you think is the right answer?
A. Q
B. P-R
C. R
D. S-T
E. T

Answer 46

D. Ventricular depolarization occurs during QRS complex. Hence, the ventricles are completely depolarized immediately after the QRS complex and before the T wave (start of ventricular repolarisation).

Question 47

Afterload is defined as the resistance against which the heart pumps blood into the systemic circulation. In the working ventricle, a sudden increase in afterload, with no change in contractility, preload, or heart rate would result in
A. An increase in end-systolic ventricular volume
B. Greater shortening of ventricular muscle fibers during ejection
C. No change in intraventricular pressure during ejection
D. A decrease in end-diastolic ventricular volume
E. A decrease in end-systolic ventricular volume

Answer 47

Option A: An increase in end-systolic ventricular volume means that stroke volume (assuming end-diastolic volume remains constant) has decreased. This is because more work is needed to increase ventricular pressure rather than eject blood from the heart.

Question 48

The percentage of the end-diastolic ventricular volume ejected with each stroke (ejection fraction) is
A. 10%
B. 20%
C. 50%
D. 65%
E. 90%

Answer 48

Option D: The typical range for ejection fraction is 55 – 70%.

Question 49

A cardiac function curve represents the relationship between cardiac output to mean right atrial pressure. Such a curve can be shifted upward or downward by changes in other variables. Which of the following would shift the curve upward (increase cardiac output at a given right atrial pressure)?
A. An increase in venous return
B. An increase in preload
C. An increase in afterload
D. An increase in heart rate

Answer 49

Option D: An increase heart rate would increase cardiac output (CO = HR x SV).

Question 50

Plasma renin activity is most likely to be lower than normal
A. In congestive heart failure
B. In hemorrhagic shock
C. In shock due to infection with gram-negative bacteria
D. In essential hypertension
E. During quiet standing

Answer 50

Option D: Since the renin-angiotensin-aldosterone system is activated in response to lowered arterial blood pressure and renal perfusion pressure, in essential hypertension where arterial blood pressure is elevated, RAAS will not be activated.

Question 51

In which of the following does heart rate vary 5% during respiratory cycle and up to 30% during deep respiration?
A. Sinus arrhythmia
B. SA node block
C. First-degree AV block
D. Second-degree AV block
E. Complete heart block

Answer 51

Option A: This is the only “physiological arrhythmia” – the respiratory sinua arrhythmia. It is caused by the spill-over of signals from the respiratory centre to the cardiac centre due to their proximity in the medulla. On the ECG, this is seen as a subtle change in the R-R interval synchronised with respiration. The R-R interval on an ECG is shortened during inspiration and prolonged during expiration. Meditation and relaxed breathing techniques can temporarily alter respiratory sinus arrhythmia.

Question 52

A 50-year-old man experiences a sudden fluttering in his chest and throat, and quickly consults his physician. The attending doctor notices his general weak health condition. The physical examination reveals regular cardiac (130 beats / min, BP (80/70 mm of Hg). The doctor applies massage on the carotid sinus area of the patient’s neck. This results in the sudden decrease of the heart rate to 80 beats/min and an increase of the BP to 110/80 mm of Hg. This change in heart rate and blood pressure in the patient may be attributed to
A. Stimulation of the vasomotor center
B. Stimulation of the cardio-inhibitory center
C. Stimulation of both the vasomotor and the cardio-inhibitory centers
D. Inhibition of the vasomotor and stimulation of the cardio-inhibitory centers
E. Inhibition of the cardio-inhibitory center

Answer 52

Option D: Carotid sinus massage stimulates baroreceptors in the carotid sinus. Afferent nervous impulses travel up the glossopharyngeal nerve to the vasomotor centre and cardio-inhibitory centre. The vasomotor centre is inhibited while the cardio-inhibitory (cardiac decelerator) centre is stimulated to decrease heart rate. The decrease in heart rate means longer filling time, increased preload, increased stroke volume, increased cardiac output and higher blood pressure.

Question 53

A 50-year old man had a blood pressure of 140/80 when supine and a blood pressure of 100/60 when standing up. What was the cause of his presentation?
A. Anaemia
B. Blood loss
C. Tachycardia
D. Hypoxia
E. Vasoconstriction

Answer 53

Option B: Blood loss results in loss of blood volume and reduced venous return. When a person stands up, the venous return falls due to the effects of gravity. With blood loss, this reduction in venous return (that ultimately leads to a drop in blood pressure) is even more significant.

Question 54

If there is an oesophageal tumor pressing anteriorly into the middle mediastinum, which of the following structures will initially be compressed?
A. Right ventricle
B. Left ventricle
C. Superior vena cava
D. Right atrium
E. Left atrium

Answer 54

E. LA makes the posterior surface of the heart

Question 55

During surgical repeat of a patent ductus arteriosus, the surgeon must be careful not to injure the:
A. Right recurrent laryngeal nerve
B. Left phrenic nerve
C. Left recurrent laryngeal nerve
D. Left vagus nerve
E. Right phrenic nerve

Question 56

In a needle biopsy penetrating the manubrium sterni, which of the following structures is least likely to be penetrated?
a. thymus
b. arch of aorta
c. pulmonary trunk
d. left brachiocephalic vein
e. left innominate brachiocephalic artery

Answer 56

C

Question 57

The following statements regarding myocarditis are true, EXCEPT:

A) Aetiologic factors include protozoa and helminths
B) It is a common complication of pericarditis
C) The histological features are variable depending on the aetiology
D) Gross pathological features include dilated heart chambers and flabby myocardium
E) Complete resolution can occur

Answer 57

b. While myocarditis and pericarditis can have overlapping symptoms, they are distinct conditions with different underlying causes and treatments.

Question 58

Total peripheral resistance is
A) Determined by myocardial contractility
B) Increased when parasympathetic activity is enhanced
C) Increased when arterioles develop low compliance
D) Increased when baroreceptors are stimulated
E) Increased during venous constriction

Answer 58

C. Total peripheral resistance describes the resistance to blood flow within the systemic circulation, and the main determinant of total peripheral resistance is the arterioles because they have small radii. Arterioles are thus used as a method of regulation of total peripheral resistance, through the sympathetic nervous system. Compliance is the measure of the change in volume for every change in unit pressure, and you can understand this by relating this to a rubber band, where circumference and force exerted on the rubber band are proxies for volume and pressure respectively: The compliant rubber band is a lax one, changing its circumference easily without much force exerted on it. When arterioles develop low compliance, they are like a tight rubber band, and thus will have smaller radii and thus greater resistance than before, causing total peripheral resistance to increase.

Question 59

Physiological splitting of the second heart sound is
A) Best heard with stethoscope over aortic area
B) Caused by the slower closure of the pulmonary valve
C) Heard during expiration
D) Heard only in children
E) Heard only in disease

Answer 59

B. The second heart sound is caused by the closure of the aortic and pulmonary valves. Splitting of the second heart sounds occurs when these valves close at different times, and this is caused by differences in the filling of the left and right ventricles, and this specifically happens during inspiration. During inspiration, the intrathoracic pressure decreases, and this increases venous return from the systemic circulation, increasing the filling of the right atrium, but at the same time it retains blood within the pulmonary circulation, decreasing venous return and filling of the left atrium. Hence there will be an increase in blood volume in the right ventricle and decrease in the left ventricle, and the increase in ventricular emptying time for the right ventricle will cause the aortic valve to close before the pulmonic valve.

Question 60

The adult right ventricle is a derivative of
A) Sinus venous
B) Ventricle
C) Bulbus cordis
D) Truncus arteriosus
E) Atrioventricular endocardial cushion

Answer 60

C. The bulbus cordis has three parts, the proximal third, the conus cordis and the truncus arteriosus. The proximal third develops to form the right ventricle. The conus cordis develops to form the infundibulum of the right ventricle and the vestibule of the left ventricle, and the truncus arteriosus develops to form the pulmonary trunk and the aorta.

Question 61

Which of the following structures DOES NOT help form the left border of the mediastinum in an anterior-posterior X-ray image of the chest?
A) Left auricle
B) Aortic arch
C) Pulmonary trunk
D) Left ventricle
E) Trachea

Answer 61

E. The trachea is pretty sad, it’s occluded by the aortic arch in the superior mediastinum.

Question 62

The oesophagus is
A) Behind the right bronchus
B) Closely related to the arch of the aorta
C) Touching the left ventricle
D) Located in the middle mediastinum
E) Is surrounded by a plexus derived mainly from the sympathetic trunk

Answer 62

B. The arch of the aorta arches over the pulmonary trunk and left bronchus to go posteriorly to the esophagus. It is here that the esophagus is constricted (it is also constricted as it passes the left bronchus and diaphragm).

The oesophagus is behind the trachea and left bronchus (bifurcates at the sternal angle of Louis). Recall that the stomach is at the left side, so the oesophagus will naturally deviate to the left side as well.

Question 63

Answer 63

A.

Heart failure is a condition where the heart is unable to pump blood effectively to meet the body’s needs. The body responds to heart failure through various compensatory mechanisms to maintain blood flow and oxygen delivery to vital organs. While these responses initially help, they can become detrimental over time. Some of the compensatory responses for heart failure include:

1. Activation of the Sympathetic Nervous System:
   
   • The sympathetic nervous system is activated to release norepinephrine, which increases heart rate and contractility.
   • This helps to maintain cardiac output, albeit at the cost of increased workload on the heart.
2. Activation of the Renin-Angiotensin-Aldosterone System (RAAS):
   
   • Reduced blood flow to the kidneys triggers the release of renin, leading to the formation of angiotensin II.
   • Angiotensin II causes vasoconstriction, stimulates the release of aldosterone (increasing sodium and water retention), and promotes the release of antidiuretic hormone (ADH), leading to fluid retention.
3. Myocardial Hypertrophy:
   
   • The heart undergoes hypertrophy (enlargement of heart muscle cells) in an attempt to increase contractility.
   • Long-term, this hypertrophy can contribute to further cardiac dysfunction.
4. Frank-Starling Mechanism:
   
   • The Frank-Starling mechanism refers to the heart’s ability to increase its force of contraction in response to an increase in blood volume.
   • This helps to maintain stroke volume and cardiac output.
5. Ventricular Remodeling:
   
   • Over time, the heart may undergo structural changes, including changes in size and shape (ventricular remodeling).
   • While initially compensatory, remodeling can lead to further dysfunction and heart failure progression.

Despite these compensatory responses, chronic activation of these mechanisms can contribute to the progression of heart failure and exacerbate symptoms. Management of heart failure often involves medications targeting these pathways, such as beta-blockers, angiotensin-converting enzyme (ACE) inhibitors, angiotensin II receptor blockers (ARBs), and diuretics, to alleviate symptoms and improve outcomes.

Question 64

Diffuse alveolar damage typically leads to which one of the following:
a. Obstructive lung disease
b. Restrictive lung disease
c. Emphysema
d. Asthma
e. Bronchiectasis”

Answer 64

B

Question 65

Which of the following does not cause acute nterstitial nephritis?
A) Drugs
B) Toxins
C) Eosinophilia in blood and urine
D) Immune complex mediated glomerulonephritis
E)Acute renal failure”

Answer 65

E.

Question 66

A 50-year old man presents with chronic cough, fever and loss of weight over the past 3 months. He has enlarged cervical lymph nodes. Lymph node biopsy reveals irregular tubules with enlarged hyperchromatic nuclei. Which of the following is the most unlikely primary tumour? A) Lung carcinoma
B) Colorectal carcinoma
C) Gastric carcinoma
D) Pancreatic carcinoma
E) Nasopharyngeal carcinoma

Answer 66

E. “Tubules” suggest that the cancer has arisen from glandular epithelium (recall that microtubules transport vesicles to the cell surface membrane for exocytosis). Since nasopharyngeal carcinoma arises from stratified squamous epithelium instead, E is likely the answer.

Question 67

Montelukast is
A. Bronchodilator
B. 5-LOX inhibitor
C. COX-2 inhibitor
D. Used as required
E. Administered orally

Answer 67

E

Question 68

Anti IgE mAb
A. Is used in the case of transplant rejection
B. Inhibit IgE production from B cell
C. Can decrease plasma IgE
D. Can decrease FcεRI receptor on mast cells
E.Can be given intravenously

Answer 68

C/D