10. Vasodilators and Diuretics

Question 1

Why is vasoconstriction important during HF?

Answer 1

redistributes blood flow to the brain and heart

Question 2

Peripheral vasoconstriction increases ________.

Answer 2

afterload

Question 3

What other tissues are compromised when blood is shunted away from periphery?

Answer 3

• kidney
• skeletal muscle
• liver

Question 4

What class of vasodilators produces the most venous dilation?

Answer 4

nitrovasodilators

Question 5

What class of vasodilators produces the least venous dilation?

Answer 5

hydralazine

Question 6

What class of vasodilators produces the most arterial dilation?

Answer 6

hydralazine

Question 7

What class of vasodilators produces the least arterial dilation?

Answer 7

nitrovasodilators

Question 8

What is the MOA of organic nitrates in HF?

Answer 8

• biotransformation to NO
• activates guanyl cyclase to ↑ cGMP
• produces SMC relaxation

Question 9

The smooth muscle relaxation produced by organic nitrates mainly has what action on the heart?

Answer 9

reduces preload

Question 10

Organic nitrates are not approved as monotherapy for HF. (T/F)

Answer 10

True

Question 11

What are organic nitrates often combined with to treat HF?

Answer 11

hydralazine

Question 12

What is the only organic nitrate approved for HF?

Answer 12

isosorbide dinitrate

Question 13

Isosorbide dinitrate is approved for what class of HF?

Answer 13

HFrEF Class III-IV

Question 14

What is nitroprusside approved for?

Answer 14

acute decompensated HF

Question 15

Nitroprusside is spontaneously converted to ____.

Answer 15

NO

Question 16

What is the route of administration of nitroprusside?

Answer 16

IV

Question 17

What is the boxed warning of nitroprusside?

Answer 17

prolonged infusions = high potential for cyanide toxicity

Question 18

What is the infusion duration maximum of nitroprusside?

Answer 18

≤ 10 minutes

Question 19

What is the MOA of hydralazine?

Answer 19

unknown

Question 20

Hydralazine reduces afterload in HFrEF patients by doing what?

Answer 20

relaxing arterial smooth muscle

Question 21

Hydralazine has the most significant effect on preload. (T/F)

Answer 21

False: minimal effect on preload

Question 22

Hydralazine is often combined with _______ to decrease preload.

Answer 22

isosorbide dinitrate

Question 23

What class of vasodilator is the most effective at reducing renal vascular resistance/ ↑ renal blood flow?

Answer 23

hydralazine

Question 24

What drug can be used to counteract the renal dysfunction created by ACE inhibitors or ARBs?

Answer 24

hydralazine

Question 25

What other vasodilators are rarely used in HF and have questionable efficacy?

Answer 25

- Prazosin | - CCBs

Question 26

What CCBs are not recommended in systolic dysfunction and why?

Answer 26

- verapamil - diltiazem - negative inotropic effect

Question 27

The treatment guidelines now recommend what with the treatment of CCBs?

Answer 27

avoid use of all CCBs in HF

Question 28

What 2 processes contribute to extracellular fluid volume expansion?

Answer 28

- adrenergic stimulation | - RAAS

Question 29

What is the adrenergic effect on fluid volume?

Answer 29

β receptor mediated release of ADH (vasopressin) from pituitary gland

Question 30

What is the effect of the RAAS on fluid volume?

Answer 30

Ang II increases aldosterone and stimulation of thirst

Question 31

What is the primary goals of diuretic therapy?

Answer 31

- reduce edema and pulmonary congestion by reducing preload | - reduce ventricular filling pressure

Question 32

Diuretic therapy causes clinically important reduction in CO. (T/F)

Answer 32

False: only when there is a rapid decline in intravascular volume

Question 33

In HF patients, reduction in preload decreases CO. (T/F)

Answer 33

False: this happens in healthy patients

Question 34

How do loop diuretic produce significant diuresis?

Answer 34

increased urinary excretion of Na, K, Cl

Question 35

What is the most widely used class of diuretics?

Answer 35

loop

Question 36

Loop diuretics can be used as a single agent in moderate and advanced HF. (T/F)

Answer 36

True

Question 37

What is the most significant problem with loop diuretics?

Answer 37

hypokalemia can precipitate life-threatening ventricular arrhythmias

Question 38

What other HF drug, when combined with diuretics, can enhance arrhythmias?

Answer 38

digoxin

Question 39

What class of diuretics can be used as monotherapy in the beginning stages of HF?

Answer 39

thiazide

Question 40

What is the site of action of thiazide diuretics?

Answer 40

distal tubule

Question 41

What are the potential complications of thiazide diuretics?

Answer 41

- ↑ excretion of K (contribute to arrhythmias) | - effectiveness reduced in patients with renal failure

Question 42

What are the Na channel inhibiting K sparing diuretic agents?

Answer 42

amiloride and triamterene

Question 43

What are the aldosterone receptor antagonist K sparing diuretics?

Answer 43

- spironolactone | - eplerenone

Question 44

What is nesiritide?

Answer 44

a purified preparation of human B-type natriuretic peptide

Question 45

What is nesiritide approved for?

Answer 45

acute decompensated HF

Question 46

What is the route of administration for nesiritide?

Answer 46

IV

Question 47

What is the mechanism of action for Ivabradine?

Answer 47

Blocks the iNa (slow) in the SA node to slow HR

Question 48

What class of HF is Ivabradine recommended for?

Answer 48

class II and III with EF ≤ 35%

Question 49

What are contraindications for Ivabradine?

Answer 49

- acute decompensated HF - rhythm disturbances - AV block

Question 50

What 2 drugs make up Entresto?

Answer 50

sacubitril and valsartan

Question 51

What class of HF is Entresto recommended for?

Answer 51

Class II – IV

Question 52

Sacubitril is a prodrug that is metabolized into what?

Answer 52

neprilysin

Question 53

What is neprilysin?

Answer 53

peptidase that degrades multiple endogenous peptides, including natriuretic peptides and bradykinin