Pharmacology Cardiovascular System Drugs 2 — Questions and Answers
Question 1: Which adverse effect is most associated with ACE inhibitors and results from bradykinin accumulation?
- Hyperkalemia
- Dry persistent cough (Correct answer)
- Angioedema of the tongue
- First-dose hypotension
Correct answer: Dry persistent cough
ACE inhibitors block the breakdown of bradykinin, causing a characteristic dry, persistent cough in up to 20% of patients.
Question 2: A patient on warfarin begins taking amiodarone. What INR adjustment is expected?
- INR will decrease; increase warfarin dose
- INR will increase; reduce warfarin dose (Correct answer)
- No change; amiodarone does not interact with warfarin
- INR will decrease; switch to a DOAC
Correct answer: INR will increase; reduce warfarin dose
Amiodarone inhibits CYP2C9, reducing warfarin metabolism and raising INR, so the warfarin dose must be reduced.
Question 3: Which calcium channel blocker subclass has the greatest selectivity for cardiac conduction tissue and is used to slow ventricular rate in atrial fibrillation?
- Dihydropyridines (e.g., amlodipine)
- Phenylalkylamines (e.g., verapamil) (Correct answer)
- Benzothiazepines (e.g., diltiazem)
- Dihydropyridines (e.g., nifedipine)
Correct answer: Phenylalkylamines (e.g., verapamil)
Verapamil (phenylalkylamine) has the highest cardiac selectivity among calcium channel blockers and effectively slows AV nodal conduction.
Question 4: Hydralazine exerts its antihypertensive effect primarily by:
- Blocking beta-1 adrenergic receptors
- Inhibiting angiotensin-converting enzyme
- Directly relaxing arteriolar smooth muscle (Correct answer)
- Blocking aldosterone receptors in the kidney
Correct answer: Directly relaxing arteriolar smooth muscle
Hydralazine is a direct-acting arteriolar vasodilator that reduces systemic vascular resistance without significant venodilation.
Question 5: Which antiarrhythmic drug prolongs the QT interval by blocking potassium channels and carries a risk of torsades de pointes?
- Lidocaine
- Metoprolol
- Sotalol (Correct answer)
- Adenosine
Correct answer: Sotalol
Sotalol (Class III antiarrhythmic) blocks IKr potassium channels, prolonging repolarization and QT interval, predisposing to torsades de pointes.
Question 6: Ezetimibe lowers LDL cholesterol by which mechanism?
- Inhibiting HMG-CoA reductase in the liver
- Inhibiting cholesterol absorption in the small intestine brush border (Correct answer)
- Activating PPAR-alpha to increase LDL clearance
- Binding bile acids in the GI lumen
Correct answer: Inhibiting cholesterol absorption in the small intestine brush border
Ezetimibe inhibits the NPC1L1 transporter at the intestinal brush border, reducing dietary and biliary cholesterol absorption.
Question 7: A patient with heart failure is started on carvedilol. Unlike metoprolol, carvedilol also blocks which receptor type, contributing to afterload reduction?
- Alpha-1 adrenergic receptors (Correct answer)
- Alpha-2 adrenergic receptors
- Dopamine D1 receptors
- Muscarinic M2 receptors
Correct answer: Alpha-1 adrenergic receptors
Carvedilol is a non-selective beta-blocker that also blocks alpha-1 receptors, causing vasodilation and reducing afterload in heart failure.
Pharmacology Cardiovascular System Drugs 2
Which adverse effect is most associated with ACE inhibitors and results from bradykinin accumulation?