Exam 1 Review

Question 1

Phase 2 is characterized by competition between ________ and __________.

Answer 1

I (CaL); I(Kr) + I(Ks)

Question 2

Giving class III antiarrhythmics (such as amiodarone) increases risk of _________.

Answer 2

torsades

Question 3

Class III drugs are used to ____________.

Answer 3

slow conduction through the AV node

Question 4

How does adenosine work?

Answer 4

It increases outflow of potassium, thereby hyperpolarizing cells and slowing conduction

Question 5

Why is lidocaine an arrhythmogenic agent?

Answer 5

Because it slows the conduction of the heart, and slowing of the heart decreases likelihood of torsades

Question 6

For patients with atrial fibrillation, ________ does not control heart rate during exercise, but _______ do.

Answer 6

digoxin; ß-blockers and caclcium-channel blockers

Question 7

What can cause late after depolarizations?

Answer 7

Ischemia, adrenergic stress (sympathetic tone), and digoxin toxicity

Question 8

What are the three kinds of HF drugs that can lead to hyperkalemia?

Answer 8

ACEI, ARBs, and ARAs