, Question 1
A patient with heart failure and reduced ejection fraction (HFrEF) is started on
sacubitril/valsartan. Which mechanism best explains the combined therapeutic
effect?
A. Inhibition of neprilysin increases natriuretic peptides, while valsartan
blocks angiotensin II AT1 receptors.
B. Sacubitril inhibits ACE, and valsartan blocks angiotensin II receptors,
reducing afterload.
C. Sacubitril increases bradykinin, and valsartan reduces aldosterone
secretion.
D. Sacubitril blocks the angiotensin II receptor, and valsartan inhibits
neprilysin.
Correct Answer: A - Inhibition of neprilysin increases natriuretic
peptides, while valsartan blocks angiotensin II AT1 receptors.
RATIONALE
Sacubitril inhibits neprilysin, increasing natriuretic peptides (ANP,
BNP) which promote vasodilation and natriuresis. Valsartan blocks
AT1 receptors, reducing vasoconstriction and aldosterone. Together
they reduce afterload and improve outcomes in HFrEF.
Question 2
Which pathophysiologic mechanism is most directly responsible for the
development of diabetic ketoacidosis (DKA) in a patient with absolute insulin
deficiency?
A. Increased counterregulatory hormones (glucagon, cortisol) leading to
unchecked lipolysis and ketogenesis.
B. Excessive insulin secretion causing hypoglycemia and subsequent
ketone body production.
C. Impaired renal excretion of ketone bodies due to dehydration.
D. Autoimmune destruction of pancreatic beta cells resulting in
Page 2
, hyperglycemia and ketosis.
Correct Answer: A - Increased counterregulatory hormones
(glucagon, cortisol) leading to unchecked lipolysis and
ketogenesis.
RATIONALE
In DKA, absolute insulin deficiency plus elevated counterregulatory
hormones (glucagon, catecholamines, cortisol, growth hormone) drive
lipolysis and hepatic ketogenesis, producing ketone bodies and
metabolic acidosis. This is the primary mechanism, not merely
hyperglycemia.
Question 3
A patient presents with sudden onset of severe, tearing chest pain radiating to
the back, with a blood pressure differential of 20 mm Hg between arms. Which
assessment finding is most critical to obtain next?
A. Immediate ECG to rule out myocardial infarction.
B. Bilateral arm blood pressures and pulse deficits.
C. Aortic regurgitation murmur and neurological deficits.
D. Serum troponin and D-dimer levels.
Correct Answer: C - Aortic regurgitation murmur and
neurological deficits.
RATIONALE
The presentation is classic for aortic dissection. While ECG and
troponin help rule out MI, the most critical next assessment is to
evaluate for aortic regurgitation and neurological deficits, which
indicate extension into the aortic valve or carotid arteries, guiding
emergent surgical intervention.
Page 3
, Question 4
A patient with major depressive disorder is prescribed phenelzine. Which
dietary restriction is essential to prevent a hypertensive crisis?
A. Avoiding foods high in potassium, such as bananas and oranges.
B. Avoiding tyramine-rich foods, such as aged cheese and cured meats.
C. Avoiding foods containing vitamin K, such as leafy greens.
D. Avoiding foods high in calcium, such as dairy products.
Correct Answer: B - Avoiding tyramine-rich foods, such as aged
cheese and cured meats.
RATIONALE
Phenelzine is a monoamine oxidase inhibitor (MAOI). Tyramine,
found in aged cheese, cured meats, and fermented products, can cause
a hypertensive crisis due to inhibited MAO in the gut. Patients must
adhere to a low-tyramine diet.
Question 5
Which of the following best explains why a patient with cirrhosis requires a
reduced dose of a drug that is primarily metabolized by CYP3A4?
A. Cirrhosis increases hepatic blood flow, enhancing first-pass
metabolism.
B. Cirrhosis decreases hepatic enzyme activity and portal blood flow,
reducing clearance.
C. Cirrhosis increases renal excretion of the drug, compensating for
hepatic impairment.
D. Cirrhosis induces CYP3A4 activity, leading to increased metabolism.
Correct Answer: B - Cirrhosis decreases hepatic enzyme activity
and portal blood flow, reducing clearance.
Page 4
A patient with heart failure and reduced ejection fraction (HFrEF) is started on
sacubitril/valsartan. Which mechanism best explains the combined therapeutic
effect?
A. Inhibition of neprilysin increases natriuretic peptides, while valsartan
blocks angiotensin II AT1 receptors.
B. Sacubitril inhibits ACE, and valsartan blocks angiotensin II receptors,
reducing afterload.
C. Sacubitril increases bradykinin, and valsartan reduces aldosterone
secretion.
D. Sacubitril blocks the angiotensin II receptor, and valsartan inhibits
neprilysin.
Correct Answer: A - Inhibition of neprilysin increases natriuretic
peptides, while valsartan blocks angiotensin II AT1 receptors.
RATIONALE
Sacubitril inhibits neprilysin, increasing natriuretic peptides (ANP,
BNP) which promote vasodilation and natriuresis. Valsartan blocks
AT1 receptors, reducing vasoconstriction and aldosterone. Together
they reduce afterload and improve outcomes in HFrEF.
Question 2
Which pathophysiologic mechanism is most directly responsible for the
development of diabetic ketoacidosis (DKA) in a patient with absolute insulin
deficiency?
A. Increased counterregulatory hormones (glucagon, cortisol) leading to
unchecked lipolysis and ketogenesis.
B. Excessive insulin secretion causing hypoglycemia and subsequent
ketone body production.
C. Impaired renal excretion of ketone bodies due to dehydration.
D. Autoimmune destruction of pancreatic beta cells resulting in
Page 2
, hyperglycemia and ketosis.
Correct Answer: A - Increased counterregulatory hormones
(glucagon, cortisol) leading to unchecked lipolysis and
ketogenesis.
RATIONALE
In DKA, absolute insulin deficiency plus elevated counterregulatory
hormones (glucagon, catecholamines, cortisol, growth hormone) drive
lipolysis and hepatic ketogenesis, producing ketone bodies and
metabolic acidosis. This is the primary mechanism, not merely
hyperglycemia.
Question 3
A patient presents with sudden onset of severe, tearing chest pain radiating to
the back, with a blood pressure differential of 20 mm Hg between arms. Which
assessment finding is most critical to obtain next?
A. Immediate ECG to rule out myocardial infarction.
B. Bilateral arm blood pressures and pulse deficits.
C. Aortic regurgitation murmur and neurological deficits.
D. Serum troponin and D-dimer levels.
Correct Answer: C - Aortic regurgitation murmur and
neurological deficits.
RATIONALE
The presentation is classic for aortic dissection. While ECG and
troponin help rule out MI, the most critical next assessment is to
evaluate for aortic regurgitation and neurological deficits, which
indicate extension into the aortic valve or carotid arteries, guiding
emergent surgical intervention.
Page 3
, Question 4
A patient with major depressive disorder is prescribed phenelzine. Which
dietary restriction is essential to prevent a hypertensive crisis?
A. Avoiding foods high in potassium, such as bananas and oranges.
B. Avoiding tyramine-rich foods, such as aged cheese and cured meats.
C. Avoiding foods containing vitamin K, such as leafy greens.
D. Avoiding foods high in calcium, such as dairy products.
Correct Answer: B - Avoiding tyramine-rich foods, such as aged
cheese and cured meats.
RATIONALE
Phenelzine is a monoamine oxidase inhibitor (MAOI). Tyramine,
found in aged cheese, cured meats, and fermented products, can cause
a hypertensive crisis due to inhibited MAO in the gut. Patients must
adhere to a low-tyramine diet.
Question 5
Which of the following best explains why a patient with cirrhosis requires a
reduced dose of a drug that is primarily metabolized by CYP3A4?
A. Cirrhosis increases hepatic blood flow, enhancing first-pass
metabolism.
B. Cirrhosis decreases hepatic enzyme activity and portal blood flow,
reducing clearance.
C. Cirrhosis increases renal excretion of the drug, compensating for
hepatic impairment.
D. Cirrhosis induces CYP3A4 activity, leading to increased metabolism.
Correct Answer: B - Cirrhosis decreases hepatic enzyme activity
and portal blood flow, reducing clearance.
Page 4
