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Flashcards in Antihypertensives Deck (31):
1

what are the ACE (angiotensin converting enzyme) inhibitors

captopril, enalapril, lisinopril

2

clinical uses of ACE inhibitors

hypertension (first line for primary)
heart failure
myocardial infarction
albuminuria in non pregnant patients

3

why aren't ACE inhibitors first line agents for blacks and elderly

because the RAAS system is less active in them

4

how does ACE inhibitors work?

- it blocks conversion of angiotensin I to angiotensin II hence reducing its vasoconstrictive activity and release of aldosterone
- blocks degradation of bradykinin and stimulates release of vasodilators such as prostacyclin and prostaglandin E2
- increase in renin since no neg feedback from angiotensin II
- slight increase in serum creatinine
- rise in K+ levels in blood if renal insufficiency

5

how do you dose the ACE inhibitors

enalapril and lisinopril given once a day while captopril given two to three times daily

6

adverse effects of ACE inhibitors

CATCHH
Cough (due to bradykinin)
Angioedema
Teratogen (fetal renal malformation; renal failure in those with bilateral renal artery stenosis)
Creatinine (increased due to decreased GFR)
Hypotension
Hyperkalemia (due to reduction in aldosterone)

7

ACE inhibitors are contraindicated in who

bilateral renal artery stenosis (no vasoconstriction by angiotensin II on the efferent arteriole to help maintain glomerular capillary pressure and filtration)
hyperkalemia (due to reduction in aldosterone release hence less sodium absorption so less K excretion)
pregnancy (teratogen -- fetal renal malformation)

8

what are the angiotensin II receptor blockers (ARBs)

Losartan
Valsartan

9

clinical use of ARBs (angiotensin II receptor blockers)

hypertension and heart failure

10

when do you switch from an ACE inhibitor to an ARB if they both work almost the same way

when the patient is experiencing the bradykinin mediated dry ass cough

11

when do ARBs work equally effective in black/oldies as it does in whites/youngings

when combined with calcium channel blockers

12

mechanism of ARBs

- they block the receptor that mediates the effects of angiotensin II hence no vasoconstriction or release of aldosterone
- don't block the breakdown of bradykinin so no dry ass cough or angioedema (as seen in ACE Inhibitors)
- since angiotensin II not activating its receptor, no negative feedback on renin release so renin still high

13

what are the adverse effects of ARBs?

hypotension
hyperkalemia (due to less aldosterone secretion hence less Na absorption so less K excretion)
angioedema
diarrhea
acute renal failure (no vasoconstriction on efferent arterioles from angiotensin II if bilateral renal artery stenosis so reduced glomerular capillary pressure and filtration)

14

contraindication of ARBs

pregnancy (fetal renal malformation)
bilateral renal artery stenosis
hyperkalemia

15

what are the calcium channel blockers (CCB)

VAND
Verapamil (diphenalkylamine)
Amlodipine (dihydropyridine)
Nifedipine (dihydropyridine)
Diltiazem (benzothiazepine)

16

clinical use of CCBs

hypertension, angina, arrhythmias

17

why would you combine CCBs with ARBs or ACE Inhibitors

because it is considered the first line drug treatment for hypertension for blacks/elderly

18

which one of the CCBs can you safely combine with beta blockers and why?

the dihydropyridines (amlodipine and nifedipine) because of their cardio depressant effects

19

mechanism of CCBs

- block voltage gated L type calcium channels on vascular smooth muscle, cardiac myocytes, and cardiac nodal tissue thereby stopping calcium from entering these cells
- this leads to smooth muscle relaxation, decreased myocardial force, decreased HR
- the dihydropyridines (in comparison to the non-dihydropyridines) only act on vascular smooth muscle hence evoke a reflex tachycardia

20

knowing that dihydropyridines only act on vascular smooth muscle while the other work on both vascular SM and cardiac tissue, what do you use each type to treat

dihydropyridines - hypertension
verapamil - angina and cardiac arrhythmias (could be used for hypertension)
diltiazem - hypertension, angina, arrhythmias

21

adverse effects of CCBs

dihydropyridines - reflex tachycardia, peripheral edema, dizziness, flushing, headache, gingival hyperplasia

non-hydropyridines (verapamil and diltiazem) - cardiac conduction abnormalities, constipation (v), anorexia, nausea, peripheral edema, hypotension

22

contraindications for CCBs

bradycardia, conduction defects, heart failure

esp don't give verapamil and diltiazem

23

alpha 1 antagonists increase the risk for CHF, so what conditions would you save alpha 1 antagonist as the treatment for hypertension

in men with BPH because drugs like tamsulosin are used to treat both BPH and hypertension

24

why should you give a small first dose to those on alpha 1 antagonist for tx for hypertension

some patients have precipitous (dangerously high) drop in BP after first dose

25

adverse effects of alpha 1 antagonist

sodium and water retention hence why a diuretic should be given in combination

26

what are the direct vasodilators

hydralazine
minoxidil

27

clinical uses of direct vasodilators

hydralazine - moderate to severe hypertension, heart failure, pregnant women with preeclampsia

minoxidil - severe hypertension and alopecia androgenetica

28

adverse effects of direct vasodilators

hydralazine - hypotension, reflex tachycardia and sodium and H2O retention, reversible lupus like syndrome,

minoxidil - hypotension, reflex tachycardia and sodium and H20 retention

29

when are beta blocker considered first line as an anti hypertensive

in patients with coronary heart disease, heart failure, or post MI

30

adverse effects of beta blockers

- drug withdrawal (abrupt cessation of beta blocker causes unstable angina, MI, tachycardia and etc because of upregulation of beta receptors)
- CV effects (bradycardia etc)
- disturbed lipid metabolism
- hypoglycemia
- bronchoconstriction
- CNS effect (reduced sexual function and fatigue)

31

contraindications for beta blockers

reactive airway disease (asthma and COPD)
pts with sinus bradycardia and partial AV block

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