Exam 2: Calcium Channel Blockers Flashcards
Calcium Channel Blockers (CCB) block “L-Type” calcium channels in 3 areas. What are the 3 area’s?
-Vascular Smooth muslce
-Cardiac Myocytes
-Cardiac Nodal Tissue
CCBs block L-type calcium channels in the cardiac myocytes. What effect does this have?
It lowers the strength of myocardial contractions
CCBs block L-type calcium channels in the Vascular smooth muscle. What 2 locations does it specifically target?
Coronary and Peripheral arteries
Calcium channels allow for Ca+ to enter through them and allow contractions to occur
If these Calcium channels are blocked by a CCB, the Ca+ cannot go through, so instead of a contraction you have what?
Relaxation/Dilation
If a CCB causes a decreased Systemic Vascular Resistance, what effect does this have on Afterload?
It decreases afterload
Vasodilation of the smooth muscles, means vasodilation of what 2 things?
What does this vasodilation cause?
Peripheral and coronary arteries
This causes increased blood flow to the heart muscles, like the myocytes
What diseases are CCBs good for?
HTN and Angina
Cardiac Myocytes are directly involved with the “blank” of heart contractions.
Involved in the strength of heart contractions
How are CCBs beneficial in a patient who needs to decrease the O2 demand of the heart?
CCBs dilate peripheral and coronary arteries which allow easier flow of blood in/out of the heart.
Then, it decreases the overall strength of the heart contractions, which lowers the amount of O2 demand the heart needs to pump blood.
Are CCBs good for heart failure?
NO!!!!!!!!!!!!!!!!!!!!!
Calcium Channel Blockers are NOT GOOD for heart failure patients
Think of CCBs as a constant decrease on heart work. CCBs DECREASE constriction, and they DECREASE heart contractions.
Assuming that CCBs effects are to DECREASE, what would you assume is their effect on the SA/AV nodes? What does this effect do?
CCBs DECREASE the SA/AV node effects.
This lowers the heart rate (SA) and the speed of conduction of the electrical impulses (AV)
Are CCBs helpful in treating dysrhythmias?
Yes!
CCBs lower the strength of contractions and lower the heart rate and electrical impulses sent by the SA/AV nodes, which can fix dysrhythmias
What is an example of a dysrhythmia that a CCB can fix?
Atrial Fibrilation
There are 2 types of CCBs: Dihydropyridines, and Non-dihydropyridines. One is Vascular selective, meaning they only work with vascular smooth muscle, and the other is myocardium selective, meaning they work with the myocardium. Which is which?
Dihydropyridines are vascular selective
Non-dihydropyridines are myocardium selective
Which of these CCBs are Dihydropyridines, and which are Non-dihydropyridines?
-Verapamil
-Amlodipine
-Diltiazem
-Felodipine
-Nifedipine
Dihydropyridines are most common for CCB’s, and end in “pine”
-Amlodipine
-Felodipine
-Nifedipine
Non-dihydropyridines are:
Diltiazem
Verapamil