Clinical Pharmacology Chapter 7 Cardiac Glycoside Digoxin Q&A ( 1 OF 20 ) Sample Questions

1. What is the primary action of digitalis therapy in Congestive Heart Failure (CHF)?
  1. A. Decreasing conduction velocity in atrial muscle, predominating over vagal tonic effect.
  2. B. Enhancing the availability of calcium to contractile proteins.
  3. C. Decrease morbidity.
  4. D. All of the above
  5. E. A and C only.
Ans: D
Tips: Digoxin’s mechanism of action in CHF:
At AV node, it decreases conduction velocity.
It increases intracellular sodium concentration.
It reduces calcium transport from the cell by sodium calcium exchanger.
It facilitates calcium entry via voltage gated membrane channel.
It increases release of calcium from sarcoplasmic reticulum.