Cardio: Drugs affecting BP

Question 1

What effect does nitric oxide have on blood vessels?

Answer 1

Vasodilation

Question 2

Organic nitrates mimic the effect of nitric oxide produced by endothelial cells. What is their effect at low dose?

Answer 2

Venorelaxation
Decrease preload
Decrease SV
No change in BP

Question 3

What is the effect of organic nitrates at high dose?

Answer 3

Arteriolar dilation
Decrease arterial pressure
Reduce after load

Question 4

Give an example of a short acting nitrate

Answer 4

GTN

Question 5

How is GTN administered?

Answer 5

Sublingually or IV infusion to avoid first pass metabolism

Question 6

Give an example of a long acting nitrate

Answer 6

Isosorbide mononitrate

Question 7

How is isosorbide mononitrate administered?

Answer 7

Orally- resistant to first pass metabolism

Question 8

What might repeated administration of nitrates result in?

Answer 8

Tolerance (decrease in effectiveness)

Question 9

What are some of the side effects of nitrates?

Answer 9

Headaches

Postural hypotension

Question 10

Why are nitrates useful in angina?

Answer 10

They redirect blood towards the ischaemic zone

Question 11

Which drugs can be used in the treatment of pulmonary hypertension?

Answer 11

Endothelin antagonists 
(Endothelin released from endothelial cells in response to excess vasodilation causes vasoconstriction of pulmonary arteries)

Question 12

Give examples of endothelin antagonists

Answer 12

Bosentan

Ambrisentan

Question 13

What do ACE inhibitors block?

Answer 13

The conversion of angiotensin I to angiotensin II

Question 14

ACEi’s inactivate bradykinin metabolism, causing it to build up. What is the adverse effect of this?

Answer 14

Dry cough

Question 15

What do ACEi’s end in?

Answer 15

‘pril’

e.g. lisinopril

Question 16

ACEi’s are first line in the treatment of what condition in caucasian patients under 55?

Answer 16

hypertension

Question 17

In which condition is use of ACEi’s contraindicated?

Answer 17

Renal artery stenosis

Question 18

What effects do ACEi’s have on the heart?

Answer 18

Decrease preload and after load - decrease BP

Question 19

What conditions are ACEi’s used to treat?

Answer 19

Hypertension
Heart failure
Post MI prophylaxis

Question 20

What do ARBs block?

Answer 20

Block the agonist action of angiotensin II at angiotensin I receptors in a competitive manner

Question 21

What do ARBs end in?

Answer 21

‘Sartan’

e.g losartan

Question 22

When might an ARB be used instead of an ACEi?

Answer 22

If a patient has a dry cough

ARBs do not inhibit bradykinin metabolism

Question 23

Which drug acts as a potassium channel openers?

Answer 23

Nicorandil

Question 24

What is nicorandil used to treat?

Answer 24

Angina

Last resort for hypertension

Question 25

What is the main side effect of nicorandil?

Answer 25

Mouth ulcers

Question 26

How do alpha1 adrenoceptor antagonists lower MABP?

Answer 26

Cause vasodilation by blocking vascular alpha1 receptors- reduced sympathetic transmission results in decreased MABP

Question 27

What to alpha1 adrenoceptor antagonists end in?

Answer 27

'Zosin' | e.g. prazosin, doxazosin

Question 28

Alpha1 adrenoceptor antagonists are particularly useful in patients with hypertension and what other condition?

Answer 28

Benign prostatic hyperplasia

Question 29

What is the main adverse effect of alpha1 adrenoceptor antagonists?

Answer 29

Postural hypotension

Question 30

How do diuretics work to lower BP?

Answer 30

They promote salt (NaCl) + water excretion by inhibiting reabsorption

Question 31

Where in the kidney do thiazide diuretics act on? Give an example of a thiazide diuretic

Answer 31

Distal tubule | Bendroflumethiazide

Question 32

Where in the kidney do loop diuretics act on? Give an example of a loop diuretic

Answer 32

Loop of Henle | Furosemide

Question 33

What are the clinical uses of diuretics?

Answer 33

Thiazide- Hypertension + mild HF | Loop- acute pulmonary oedema + Chronic HF

Question 34

What are the 4 main side effects of diuretics?

Answer 34

Hypokalaemia Hyperglycaemia Increased uric acid (gout) Impotence

Question 35

Which drug is known as a 'potassium sparing diuretic'

Answer 35

Spironolactone

Question 36

Which receptor does spironolactone block?

Answer 36

Aldosterone receptor (antagonist)

Question 37

When is spironolactone used?

Answer 37

Moderate- severe heart failure

Question 38

What is the main side effect of spironolactone?

Answer 38

Gynaecomastia

Question 39

Which drug acts as a renin inhibitor?

Answer 39

Aliskiren

Question 40

What is aliskiren used to treat?

Answer 40

Hypertension