Okay, let’s talk about angiotensin II receptor blocking agents,
we call those ARBs for short so let’s run with that from here on out.
How these guys work is they block the vasoconstriction effects of angiotensin II
because they block access to the receptors; so when you give someone an ARB,
you put the drug on that angiotensin II receptor and it blocks it, so even though you have lots of angiotensin II from the RAAS,
it’s all dressed up and no place to go because you have wisely blocked that receptor with an ARB.
Now, these guys have an ending that’s the same too, it’s TAN,
which I love the picture that the Lecturio graphic artist used,
like she’s blocking her face from the sun. So this will help to remind you, this is a blocker and it ends in TAN -
olmesartan, telmisartan, irbesartan, losartan -- it’s all tan, tan, tan.
So while you're in that mode, see if you can pause and recall what is the four letter ending for ACE inhibitors?
Now with ARBs, we’ll talk about the types of patients that we would use these for.
Many of the ARBs have some different applications with cardiovascular health and I’m gonna go over those
but all of them treat hypertension, so each of the ARBs, the angiotensin II receptor blocking agents treat hypertension,
but two of them -- irbesartan, losartan -- are used for diabetic nephropathy.
Losartan is also used for diabetic retinopathy -- challenge to the eyes.
Valsartan is used after a heart attack, a myocardial infarction or MI.
Losartan is also approved to reduce the stroke risk in hypertensive patients with left ventricular hypertrophy.
So left ventricle -- I know you know what that means -- we're talking about the heart.
Hypertrophy means -- hyper means big or elevated, trophy means growth.
So we can use Losartan to reduce the risk of people who have high blood pressure with that left ventricle that’s gotten too big.
Remember the left ventricle gets too big because the SVR,
the systemic vascular resistance is high after the heart probably because the vessels have a narrow diameter,
or they might be narrowed because either of vasoconstriction, right, those arteries has been constricted
or they could have coronary artery disease and those vessels are kind of filling up with plaque
so because that heart has had to work to so hard and it’s the left ventricles job to push blood
throughout the rest of the body when you over work it like that with hypertension it becomes hypertrophy,
hypertrophy that gets bigger to try to overcome that and eventually that’s gonna become a real problem for your heart.
Now for patients who are a little bit older if you’re pretty young you think 55 is like wow,
geriatric, but I promise you, as you get close to that age, it doesn’t seem quite so old;
but we have patients who are 55 plus or they can’t tolerate ACE inhibitors
because remember those three side effects that spell A-C-E?
Write those in the margin of your notes see if you can remember the three side effects of ACE inhibitors that stand for A-C-E.
Now add just a couple more to see what a rock star that you are for ACE inhibitors.
Okay if somebody is 55 and over, somebody who can't tolerate an ACE inhibitor
and they have some cardiovascular risk like they’ve had a heart attack before, they’ve had a stroke -
we’re gonna help reduce those risk so telmisartan is the one that we recommend for that -
if they’ve had some type of other MI or cardiovascular event.
Now what are the side effects?
Well, remember for -- cuz I know you just wrote them down for ACE inhibitors,
you can also have some angioedema, a small risk for this with ARBs.
Now, it has a lower risk of cough than ACE inhibitors do,
but they still might also develop a cough with an ARB, so they may or may not develop that cough.
The cool part is it will not increase the serum potassium.
Remember anytime you see the word serum in front of something that tells you,
"Hey, that’s a blood level." So that tells us what the potassium level is in the blood
it doesn’t tell us what’s going on inside the cell just what’s going on in the blood.
Remember, we don’t use ACE inhibitors for people who are pregnant
and you shouldn’t use ARBs for patients who are pregnant, that’s why it’s in a big red box for you there.