L18- drugs to treat angina and cardiac failure

Question 1

What is the basic problem in angina and heart attack?

Answer 1

Heart is deprived of oxygen. cells die

Question 2

What is heart failure?

Answer 2

A condition in which th heart can;t pump efficiently enough to supply the body;s oxygen needs.

Question 3

What can angina, heart attacks and heart failure lead to?

Answer 3

dysrhythmias

Question 4

What is coronary artery disease?

Answer 4

When fatty deposits clog up the coronary blood supply. (atherosclerosis). This restricts blood flow and hence oxygen to the heart.

Question 5

How can you prevent coronary artery disease?

Answer 5

Lifestyle interventions

Reduce blood pressure

statins to reduce cholesterol

Question 6

What’s a stenosis?

Answer 6

a narrowing of a coronary artery by fatty plaque

Question 7

What is a heart attack?

Answer 7

When the cardiac muscle becomes ischaemic for so long that some dies

Question 8

What can heart attack cause in the heart?

Answer 8

lead to scarring and set the scene for dysrhythmias. Also has lost pumping ability.. could be leading to heart failure

Question 9

How do you treat a heart attack?

Answer 9

• Glyceryl trinitrate, propranolol. - reduces workload and improve blood flow through coronary arteries, reduce pain.
• Tissue plasminogen activator- clot buster. only works if given within a few hours of MI
• Angioplasty- stent and balloon to open vessel

Question 10

Which drug can reduce workload and oxygen demand to trat an MI?

Answer 10

Glyceryl trinitrate

Propranolol

Question 11

What can bust clots to treat an MI?

Answer 11

Tissue plasminogen activator

Question 12

What are 2 non-pharmacological interventions for angina?

Answer 12

angioplasty- balloon and stent

Bypass surgery- taking blood vessel from another pat of the body and grafting it into the heart

Question 13

What risk does bypass surgery have?

Answer 13

cognitive decline after surgery, perhaps due to embolism travelling to brain

Question 14

When cardiac muscle cells become ischameic what dot hey release?

Answer 14

Pain mediators such as adenosine, bradykinin and potassium

Question 15

What are the 3 types of angina?

Answer 15

1. stable angina (angina of effort)
2. Unstable brittle angina
3. Variant Pririzmetal’s angina

Question 16

What causes stable angina?

Answer 16

Atherosclerosis of coronary arteries. Triggered by exercise and excitement

Question 17

WHat causes unstable angina?

Answer 17

Disruption of a pre-exisiting atherosclerotic plaque. Causing thrombus

Question 18

What causes variatna angina and how common is it?

Answer 18

Rare. Caused by vasospasm. Coronary blood vessels clamp down

Question 19

What are the two ways to treat angina?

Answer 19

1. Reduce O2 demand
2. Increase O2 supply

Question 20

Name 6 treatments of angina, including those to treat the causes of the disease?

Answer 20

1. Aspirin- to prevent clotting
2. Statins- lower lipids in blood
3. Organic nitrates
4. Antagonist at B adrenoceptors
5. Ca channel blocker
6. K channel activator– vasodilation

Question 21

Give an example of a K channel activator?

Answer 21

Nicorandil

Question 22

What happens once a drug has been absorbed by the gut?

Answer 22

Enter the hepatic portal vein

The enzymes of the liver break down some of the drug into metabolites

The rest will enter the body

Question 23

What is the bioavailability of the drug?

Answer 23

The amount of drug that reaches the body (and doesn’t get chewed up into metabolites).

The more that can get past the liver, the better

Question 24

What are these methods of delivery?

Buccal

Parenteral

Enteral

Answer 24

buccal- mouth cavity

parenteral- injected

enteral- through GI tract. sometimes wastes a lot by digestion in liver

Question 25

What;s the oldest group of drugs used to treat angina?

Answer 25

The nitrovasodilators. activators of soluble gunaylate cyclase.

Question 26

How was the vasodilator action of nitroglycerine discovered?

Answer 26

Workers producing dynamite suffered terrible headaches on monday mornings, which faded by midweek. They experienced vasodilation in the brain caused by nitroglycerine

Question 27

What is GTN?

Answer 27

Glyceryl trinitrate (nitroglycerin)

Question 28

How is GTN administered? Why?

Answer 28

GTN is actually the prodrug. NO is the active part. It has to be broken down to NO next to the tissue to work. Can’t be swallowed. Would be broken down by the liver and not reach the target tissue.

Sublingually or buccal.

Question 29

What does NO nitric oxide do?

Answer 29

It’s derived from organic nitrates like nitroglycerine. Activated CGMP, activates PKG, leads to vasodilation

Question 30

What are the main methods that organic nitrates releive angina?

Answer 30

1. reduce cardiac workload
2. dilate collateral vessels in the heart

Question 31

How does GTN reduce cardiac workload?

Answer 31

Dilates peripheral vessels. Heart doesn’t have to pump as hard.

Less blood returned to the heart- lower force of contraction. (less resistance.)

Question 32

What is the Frank- Starling law of the heart?

Answer 32

More blood going into the heart, the harder it has to contract

Question 33

What’s a nnitrate that can be swallowed?

Answer 33

Isosorbide dinitrate

Question 34

What does the activity of isosorbide dinitrate depend on?

Answer 34

Depends on metabolism by the liver to break it down to mononitrates.

Question 35

What’s the con of isosorbide dinitrate?

Answer 35

Tolerance development is likely

Question 36

What are the unwanted effects of nitrates?

Answer 36

Mostly linked to vasodilation

flushing of skin

tachycardia

headache

orthostatic hypotension (fainting)

Question 37

What drug activates K channels and is also an NO donor?

Answer 37

Nicorandil

Question 38

What are the unwanted effects of nicorandil?

Answer 38

fushing, headache, hypotension, similar to GTN -

usually caused by vasodilation