CCS CCS Pharmacology & Cardiovascular Medications 1 — Questions and Answers
Question 1: Which class of antiarrhythmic drug works by blocking sodium channels and is classified as a Class I agent?
- Lidocaine (Correct answer)
- Amiodarone
- Metoprolol
- Verapamil
Correct answer: Lidocaine
Lidocaine is a Class IB antiarrhythmic that blocks sodium channels, slowing conduction in depolarized tissue.
Question 2: A patient on warfarin therapy should have their INR maintained in what therapeutic range for atrial fibrillation?
- 1.0–1.5
- 2.0–3.0 (Correct answer)
- 3.5–4.5
- 4.5–5.5
Correct answer: 2.0–3.0
For atrial fibrillation, the therapeutic INR range for warfarin anticoagulation is 2.0–3.0 to balance stroke prevention and bleeding risk.
Question 3: Which medication is the first-line treatment for acute anaphylaxis that can cause cardiovascular collapse?
- Diphenhydramine
- Epinephrine (Correct answer)
- Methylprednisolone
- Albuterol
Correct answer: Epinephrine
Epinephrine (1:1000, 0.3–0.5 mg IM) is the first-line treatment for anaphylaxis due to its vasoconstrictive and bronchodilatory effects.
Question 4: Beta-blockers such as metoprolol reduce heart rate primarily by which mechanism?
- Blocking calcium channels in the SA node
- Antagonizing beta-1 adrenergic receptors in the heart (Correct answer)
- Inhibiting the sodium-potassium ATPase pump
- Stimulating muscarinic receptors in cardiac tissue
Correct answer: Antagonizing beta-1 adrenergic receptors in the heart
Beta-blockers antagonize beta-1 adrenergic receptors in the heart, reducing the chronotropic and inotropic effects of catecholamines.
Question 5: Which antiplatelet medication inhibits ADP-mediated platelet aggregation and is commonly prescribed after coronary stent placement?
- Aspirin
- Clopidogrel (Correct answer)
- Heparin
- Warfarin
Correct answer: Clopidogrel
Clopidogrel is a P2Y12 receptor antagonist that inhibits ADP-mediated platelet aggregation and is used for dual antiplatelet therapy after stenting.
Question 6: Nitroglycerin relieves angina primarily by which action?
- Increasing myocardial oxygen demand
- Causing coronary and peripheral vasodilation (Correct answer)
- Reducing heart rate by blocking beta receptors
- Inhibiting platelet aggregation
Correct answer: Causing coronary and peripheral vasodilation
Nitroglycerin is converted to nitric oxide, causing smooth muscle relaxation and vasodilation of coronary and peripheral vessels, reducing preload and myocardial oxygen demand.
CCS CCS Pharmacology & Cardiovascular Medications 1
Which class of antiarrhythmic drug works by blocking sodium channels and is classified as a Class I agent?