Antanginals Based On Review Flashcards
What is a risk of all vasodilators?
Risk of decreasing coronary flow
Shortened diastole, lowered perfusion pressure during diastole
What is the MOA of nitrates/nitrites?
It increases the release of NO
No stimulates Guanylyl Cycylase= lots of cGMP
Lots of cGMP=Myosin LC RELAXATION
Which does nitroglycerin dilate more: veins or arteries
Large Veins
Uneven vasodilation
Why do nitrites help in angina?
Decreasing myocardial O2 requirement!
(They decrease preload (venous dilation)
Decrease afterload (some arteriole dilation))
Do nitrates cause reflex tachycardia
Oh yeah ⏱
Why is nitroglycerin taken sublingually?
Because if you give it orally, the liver will destroy almost all of it on the “first pass”
This allows for rapid absorption and immediate angina relief
How long does it take for nitrates to kick in
1-3 min
What are the adverse effects of nitroglycerin
Throbbing headaches (big diff b/w diastolic and systolic pressure)
Orthosstatic hypotension
Tachycardia
Can patients use nitroglycerin long term?
No, they will build up tolerance fast
What is “Monday disease”
Guys who make explosives would get headaches and dizziness on Monday and Tuesday, and then by Friday, their symptoms would disappear due to developing tolerance to nitro over the week.
Then by the following Monday, sensitivity is restored and their headaches are back.
What is the IV form of nitro?
Nitroprusside
What is the MOA of calcium channel blockers?
Block calcium channel on membrane of muscle cells
=no ca/calmoduliun to activate myosin LC Kinase
=muscle contraction impossible
What are the 3 main calcium channel blockers discussed in this lecture
Nifedipine (and other dihydropyridines -dipines)
Verapamil
Diltiazem
Which CCB has the MOST effect on vascular smooth muscle
Nifedipine (and other -dipines)
Which CCB has the LEAST effect on vascular smooth muscle
Verapamil