ECG Cardiac Pharmacology 3

Question 1

Atropine is administered to a patient in symptomatic bradycardia. What is its mechanism of action on the heart?

Accepted Answer

Blocks muscarinic receptors, increasing heart rate

Answer

Stimulates beta-1 receptors, increasing contractility

Answer

Blocks alpha receptors, reducing afterload

Answer

Inhibits sodium channels, stabilizing membranes

Question 2

Which medication used in ACLS for ventricular fibrillation works by blocking both sodium and potassium channels?

Accepted Answer

Amiodarone

Answer

Epinephrine

Answer

Magnesium sulfate

Answer

Vasopressin

Question 3

A patient in torsades de pointes should receive which treatment to stabilize cardiac membranes?

Accepted Answer

IV magnesium sulfate

Answer

Amiodarone infusion

Answer

Digoxin loading dose

Answer

Oral flecainide

Question 4

Propranolol's cardiac effects are primarily due to blockade of which receptor?

Accepted Answer

Beta-1 adrenergic receptors

Answer

Alpha-1 adrenergic receptors

Answer

Muscarinic M2 receptors

Answer

Dopamine D1 receptors

Question 5

Which drug is given during CPR primarily to increase systemic vascular resistance and improve coronary perfusion pressure?

Accepted Answer

Epinephrine

Answer

Amiodarone

Answer

Lidocaine

Answer

Atropine

Question 6

Procainamide belongs to which antiarrhythmic class and produces which metabolite that also has antiarrhythmic properties?

Accepted Answer

Class IA; N-acetylprocainamide (NAPA)

Answer

Class IB; lidocaine metabolite

Answer

Class IC; moricizine

Answer

Class III; dofetilide metabolite

Question 7

Which ECG finding would indicate that a patient's beta-blocker is producing therapeutic effects?

Accepted Answer

Decreased resting heart rate and prolonged PR interval

Answer

Shortened QTc and narrow QRS

Answer

ST segment elevation

Answer

Development of delta waves