Vasodilators

Question 1

AT1 Receptors

Answer 1

• Angiotensin II binds to AT1 receptors
• Present on vascular smooth muscle and adrenal gland
• Stimulate constriction and aldosterone secretion, respectively

Question 2

DRI

Answer 2

• EX: Aliskiren
• Direct Renin Inhibitor
• Competitively inhibits angiotensinogen from binding to renin
• Decreases Ang II synthesis
• Reduces vasoconstriction and aldosterone secretion

Question 3

ACE-I

Answer 3

• Competitively inhibits ACE from converting Ang I to Ang II
• Reduces vasoconstriction and aldosterone secretion
• ALSO, inhibits degradation of bradykinin which increases vasodilation

Question 4

ARBs

Answer 4

• Antagonists of AT1 receptors

- Reduces vasoconstriction and aldosterone secretion

Question 5

DRI, ACE-I, and ARBsare used to treat….

Answer 5

Uncomplicated hypertension

Question 6

Examples of ACE-Is

Answer 6

• Quinapril (Accupril)
• Benazepril (Lotensin)
• Enalapril (Vasotec)
• Ramipril (Altace)
• Lisinopril (Prinivil)
• Fosinopril (Monopril)

Question 7

Examples of ARBs

Answer 7

• Olmesartan (Benicar)
• Irbesartan (Avapro)
• Valsartan (Diovan)
• Losartan (Cozaar)
• Candesartan (Atacand)

Question 8

1st Line therapy for CKD/Type II DM

Answer 8

ACE-I and ARBs

Question 9

ACE-Is + Hepatic Excretion

Answer 9

• Benazepril (Lotensin)
• Ramipril (Altace)
• Fosinopril (Monopril)
• Trandolapril

Preferred for those with CKD

Question 10

RAS-I SE

Answer 10

• Hyperkalemia (K > 5 mEq/L) - from reduced aldosterone synthesis
• Mild Elevation of Serum Creatinine - dilation of flomerular efferent arteriole, reduces filtration pressure and thus GFR
• *30% increase in SCr -= acceptable**

Question 11

RAS-I + Pregnancy

Answer 11

• DO NOT USE

- D/C if preggo or planning on becoming preggo

Question 12

ACE-I SE

Answer 12

• Dry cough - develops in about 1-10% of patients, believed to be due to increased bradykinin
• Angioedema - NOT an allergic response, also due to increased bradykinin (Can be fatal, is rare, most common with ACE-I)

Question 13

24-H BP Goal

Answer 13

• Trough/Peak > 50%
• Want to meet this above criteria when picking ACE-I or ARB for once a day use
• Allows for less exaggerated peak response
• More uniform 24 hour control

Question 14

ACE-I not good for 24-H Use

Answer 14

• QUinapril (50%)
• Benazepril (50%)
• Enalapril (50%)
• Captopril (25%)

QuBEC

Question 15

CCBs

Answer 15

• Stop the efflux of Ca which activates vasoconstrictors

- By blocking these influxes you block their downstream vasoconstrictive actions

Question 16

Dihydropyridine

Answer 16

• Type of CCB
• Blocks calcium efflux in arterioles
• Reduces PVR by dilating arterioles
• “dipine”

Question 17

Non-dihydropyridines

Answer 17

• Type of CCB
• Blocks calcium efflux in SA node and ventricular cardiac myocytes
• Slow HR
• Reduce cardiac contractile force

EX: Verapamil, Diltiazem

Question 18

CCBs used to treat…

Answer 18

Uncomplicated HTN

Question 19

CCB SE

Answer 19

• ALL: hypotension, flushing, dizziness
• Dihydropyridine: peripheral edema (from dilation of arterioles increasing capillary pressure and drawing fluid out)
• Non-dihydropyridine: bradycardia

Question 20

CCBs + Preggo

Answer 20

• Limited clinical evidence

- Nifedipine is one of the three agents okay to use

Question 21

Other Antihypertensives for Preggo

Answer 21

• Methyldopa

- Labetalol

Question 22

Minoxidil

Answer 22

-Activate K+ efflux directly
-Prevent Ca+2 channel opening
-Target: Arterioles
-Use: Resistant HTN
SE: Fluid rentention (+diuretic) and Tachycardia (+B-blocker)

Question 23

Hydralazine

Answer 23

• Activate K+ efflux directly
• Prevent Ca+2 channel opening
• Target: Arterioles
• Uses: Resistant HTN (oral), HTN crisis (IV), preeclampsia, eclampsia
• SE: tachycardia
• CI: CAD

Question 24

Nitroprusside

Answer 24

• Metabolized to release NO
• Target: arteries and veins
• Use: HTN Crisis (IV)
• SE: Cyanide toxicity

Question 25

Nitroglycerin

Answer 25

• Metabolized to release NO
• Target: arteries and veins
• Use: HTN Crisis (IV)
• SE: Headache, tachycardia

Question 26

Fenoldopam

Answer 26

• Activate dopamine receptor D1 and K+ efflux
• Target: Arterioles
• Use: HTN Crisis (IV)
• SE: Headache and nausea