Calcium Channel Blockers

Question 1

MOA

Answer 1

1) Action on cardiac muscles:
Decreases force of contraction (-inotropic)

1) Action on cardiac conduction:
Decrease automaticity in SA node
Decrease conduction in AV junction (-dromotropic)
Results in:
Decrease HR, a -chronotropic effect

1) Action on vascular smooth muscle:
Vasodilation of coronary artery (reduction in BP)

Question 2

Dihydropyridines

Answer 2

Only actions 1 & 3:

Decrease contractility
Vasodilation

-ipine

Question 3

Non-Dihydropyridines

Answer 3

All three MOA:

Decrease contractility and HR
Vasodilation

Diltiazem
Verapamil

Question 4

Calcium channel blockers

Clinical indications

Answer 4

Afib/flutter

HTN

Angina pectoris

Supraventricular tachycardias

Question 5

Calcium channel blockers
SE/AR

Answer 5

Vasodilation
HA
**ankle edema

Flushing
Fatigue
Sinus bradycardia (atropine to reverse)
AV blocks
Palpitation

Question 6

Calcium channel blockers
Nursing considerations
When to be cautious
What to do if
Pt education

Answer 6

Administer cautiously to pts with:
Hypotension
CHF
Sick sinus sydrome
AV delays
Renal failure

Hold dose and notify provider if:
HR<60 SBP<90

Pt education on SE: Orthostatic hypotension, VS

Question 7

Calcium channel blockers overview

Answer 7

Cause:
Decrease contractility
Decrease conductivity of the heart