Properties of antianginal agents

Question 1

What is the MOA of nitrates?

Answer 1

1. Converted to NO by endothelial cells
2. This increase cGMP
3. this causes vasodilation of venous capacitance
4. This decreases preload
5. this decreases O2 demand

Question 2

What is the MOA of calcium channel blockers?

Answer 2

1. They block L-type calcium channels in vascular smooth muscle
2. this causes vasodilation
3. thus decreases preload
4. decreased preload helps the heart work less so that decreases O2 demand

They also dilate coronary vessels allowing more O2 to be delivered to heart

Question 3

what is the MOA of Beta blockers assuming they are cardiac specific?

Answer 3

they block cardiac B1 receptors which causes

1. decreased HR
2. decreased BP
3. decreased contractility

the decrease in these three things cause a decrease in O2 demand

Question 4

What type of drug needs a 8-14 hr drug free interval to decrease tolerance?

Answer 4

Nitrates

Question 5

How are nitrates eliminated?

Answer 5

High 1st pass metabolism- need a large oral dose

Question 6

How are CCBs metabolized?

Answer 6

by CYP450 which can be a source of DDI

Question 7

How is metoprolol eliminated?

Answer 7

primarily by metabolism

Question 8

how is atenolol eliminated?

Answer 8

primarily renal T1/2= 6-9 hours

Question 9

Adverse effect of nitrates?

Answer 9

Death if taken with ED drugs

but mainly therapeutic vasodilation causing HA, hypotension, syncope, reflex tachy, flushing

Question 10

Adverse effect of CCB’s

Answer 10

1. Negative chronotropic effect = decreased HR, AV block (V>D)
2. negative inotropic effect= heart failure block (V>D)
3. hypotension
4. peripheral edema (A>V>D) amlodipine, verapamil, dilt
5. constipation mostly with verapamil

Question 11

Adverse effects of beta blockers?

Answer 11

1. B1 = decreased contractility= acute heart failure
2. B2: worsen preexisting astha-bronchospasm
3. increase blood lipids, decrease peripheral circulation
4. increased lipid solubility means increased CNS adverse reactions like sedation, sleep disturbances and fatigue
5. Avoid if Pt has severe brady, PVD, asthma

Question 12

DDI for nitrates

Answer 12

welp that would be PDE-inhibitors (sildenafil)

Question 13

DDI for CCB’s

Answer 13

1. cP levels are increased with grapefruit juice

2. cP levels decreased by cyp450 inducers

Question 14

DDI for beta blockers

Answer 14

concomitant use of negative inotropic or chronotropic agents

Question 15

What is the drug of choice for acute anginal episode?

Answer 15

SL nitroglycerine

can be used for vairant angina but not first line

nitrates can also be added on to beta-blockers if better control is needed

Question 16

What is the drug of choice for variant angina?

Answer 16

these would be CCB

amlodipine
Verapamil
diltiazem

They can used for stable angina if beta-blockers are not well tolerated

Question 17

So what is the drug of choice for stable angina?

Answer 17

Beta-blockers

Metoprolol and atenolol