Pharmacology Cardiovascular System Drugs Questions and Answers 1 — Questions and Answers
Question 1: A patient being treated for hypertension with lisinopril presents with a persistent, non-productive cough. This adverse effect is primarily attributed to the accumulation of which substance?
- Angiotensin II
- Bradykinin (Correct answer)
- Aldosterone
- Norepinephrine
Correct answer: Bradykinin
Angiotensin-converting enzyme (ACE) is responsible for the breakdown of bradykinin. By inhibiting ACE, lisinopril causes an accumulation of bradykinin in the respiratory tract, which can lead to bronchial irritation and a characteristic dry cough.
Question 2: A 65-year-old male on long-term atorvastatin therapy for hypercholesterolemia presents with severe muscle pain, tenderness, and weakness. Which laboratory value is most critical to assess for potential rhabdomyolysis?
- Alanine Aminotransferase (ALT)
- Serum Creatinine
- Creatine Kinase (CK) (Correct answer)
- Alkaline Phosphatase (ALP)
Correct answer: Creatine Kinase (CK)
Statin-induced myopathy is a serious adverse effect that can progress to rhabdomyolysis. Creatine kinase (CK) is an enzyme released from damaged muscle tissue. Markedly elevated CK levels (typically >10 times the upper limit of normal) are the hallmark laboratory finding for rhabdomyolysis.
Question 3: The use of a non-selective beta-blocker, such as propranolol, is contraindicated in which of the following patient populations due to the high risk of acute exacerbation?
- Patients with essential tremor
- Patients with migraine headaches
- Patients with hyperthyroidism
- Patients with asthma (Correct answer)
Correct answer: Patients with asthma
Non-selective beta-blockers block both beta-1 and beta-2 adrenergic receptors. Blocking beta-2 receptors in the bronchial smooth muscle prevents bronchodilation and can lead to severe bronchoconstriction, which is particularly dangerous for patients with asthma.
Question 4: An elderly patient with chronic heart failure and renal impairment is taking digoxin. The patient develops nausea, vomiting, and visual disturbances. Which electrolyte abnormality significantly increases the risk of digoxin toxicity?
- Hypokalemia (Correct answer)
- Hypernatremia
- Hyperkalemia
- Hypocalcemia
Correct answer: Hypokalemia
Digoxin exerts its effect by inhibiting the Na+/K+-ATPase pump. Potassium and digoxin compete for the same binding site on this pump. When potassium levels are low (hypokalemia), more binding sites are available for digoxin, leading to an enhanced effect and increased risk of toxicity, even at therapeutic serum drug levels.
Question 5: What is the primary mechanism by which sublingual nitroglycerin provides rapid relief from an acute anginal attack?
- Increasing myocardial contractility (positive inotropy)
- Venodilation leading to a decrease in myocardial preload (Correct answer)
- Arterial vasoconstriction to improve coronary perfusion pressure
- Directly dissolving atherosclerotic plaques
Correct answer: Venodilation leading to a decrease in myocardial preload
Nitroglycerin is converted to nitric oxide, a potent vasodilator. Its primary effect is on the systemic veins, causing venodilation. This reduces the volume of blood returning to the heart (preload), which in turn decreases ventricular wall tension and myocardial oxygen demand, thus relieving anginal pain.
Question 6: A patient who is stable on a long-term warfarin regimen for atrial fibrillation requires treatment for a fungal infection. Co-administration of which of the following medications would most likely lead to a dangerously high INR and increased risk of bleeding?
- Nystatin
- Amphotericin B
- Fluconazole (Correct answer)
- Rifampin
Correct answer: Fluconazole
Warfarin is primarily metabolized by the hepatic enzyme CYP2C9. Fluconazole is a potent inhibitor of CYP2C9. By inhibiting this enzyme, fluconazole decreases the metabolism and clearance of warfarin, leading to elevated plasma concentrations, a significantly increased INR, and a high risk of major bleeding.
Pharmacology Cardiovascular System Drugs Questions and Answers 1
A patient being treated for hypertension with lisinopril presents with a persistent, non-productive cough.
This adverse effect is primarily attributed to the accumulation of which substance?