Cardiovascular Therapeutics

Question 1

What is typically prescribed for chronic heart failure?

Answer 1

ACEIs, diuretics, β blockers

digoxin?

Question 2

What is typically prescribed for hypertension?

Answer 2

ACEIs, calcium channel inhibitors

Question 3

Give two examples of ischaemic heart disease

Answer 3

Angina

MI

Question 4

What to prescribe for LV dysfunction when there are persistent symptoms after use of ACEI/β blockers?

Answer 4

cough - ATRA

aldosterone antagonist or hydralazine plus nitrate

Question 5

What to prescribe for LV dysfunction when there are persistent symptoms after use of aldosterone antagonist/hydralazine plus nitrate?

Answer 5

AF - digoxin

sinus - ivabradine

Question 6

What is IHD an important cause of?

How?

Answer 6

congestive heart failure
MI - destroyed part of the heart
or change in ischaemia decreases function of myocytes

Question 7

What causes IHD?

Answer 7

associated with atherosclerosis within coronary artery - impaired blood flow or thromboembolic occlusion
coronary blood flow does not match demand of the muscle

Question 8

When do symptoms begin to occur?

Answer 8

stenosis of the coronary artery due to atheroma

Question 9

Risk factors of IHD

Answer 9

male (female hormones protect)
family history (<55 m, <65 f)
smoking
diabetes
hypercholesterolaemia - high LDL:HDL
hypertension
sedentary lifestyle
obesity
dental hygiene

Question 10

Major varities of angina

Answer 10

stable

unstable

Question 11

What is stable angina?

Answer 11

atherosclerotic disease which limits heart’s ability to respond to increased demand
symptoms on exertion, relieved by rest

Question 12

What is unstable angina?

Answer 12

plaque rupture and the formation of a non-occlusive thromboembolism OR vasospasm
symptoms at rest

Question 13

How to diagnose stable angina?

Answer 13

History - chest pains on exertion
stable angina: pain induced by exercise and relieved by rest
GTN - nitrate spray, rapid relief
ECG - ST segment depression - below baseline
Angiography of coronary arteries - catheter, squirt radioactive dye

Question 14

Management of stable angina

Answer 14

lifestyle - stop smoking, exercise, diet (fruit, veg, oily fish), weight
coronary artery bypass grafting
angioplasty and stenting

Question 15

What is PTCA

Answer 15

percutaneous transluminal coronary angioplasty

treatment for IHD

Question 16

Procedure for PTCA

Answer 16

catheter into coronary artery, while taking x-rays
inflate balloon to open vessels
stent inserted, some have drug eluting chemicals which inhibit vascular growth

Question 17

What are ps undergoing PTCA given beforehand?

and why?

Answer 17

anti-platelets and heparin

inflation of balloon is thrombogenic - prevent further coagulation

Question 18

Pharmalogical management of stable angina

Answer 18

nitrates - glyceryl trinitrate (GTN) via release of NO, spray under the tongue - rapid relief
causes venodilatation (main point) and coronary vasodilatation

Question 19

What happens if angioplasty occurs without a stent?

Answer 19

restenosis - blocked again by more plaque due to damage to the blood vessel and therefore further coagulation

Question 20

What does venodilatation do?

Answer 20

decreases preload and reduces cardiac work

Question 21

Action of GTN

Answer 21

glyceryl trinitrate donates NO into circulation

activates guanylyl cyclase and leads to release of cGMP, causes venodilatation

Question 22

What type of nitrates can cause problematic nitrate tolerance?

Answer 22

oral nitrates

Question 23

How to prevent nitrate tolerance?

Answer 23

aim for nitrate free period

2 doses, rather than 3 per day eg. at night

Question 24

What is the first choice drug for prevention against IHD?

Answer 24

β-blocker - atenolol

Question 25

How is atenolol anti-anginal? Why does this work?

Answer 25

negative inotropic and chronotropic effects coronary flow is only during diastole, so slowing the heart will increase diastolic period, including the time for coronary blood flow therefore it reduces cardiac work and prevents symptoms

Question 26

How does atenolol reduce the risk of MI?

Answer 26

anti-arrhythmic effects reduce risk of MI

Question 27

What dose of atenolol is used for angina?

Answer 27

high dose atenolol

Question 28

Problems of atenolol

Answer 28

p with angina can develop chronic heart failure which is worsened by high dose atenolol - reduces contractility (-ve inotrope) therefore use bisoprolol

Question 29

Alternative to beta blockers

Answer 29

calcium channel blockers | eg. amlodipine

Question 30

Types of calcium channel blockers

Answer 30

rate limiting agents (diltiazem and verapamil) | dihydropyridines (amlodipine)

Question 31

Rate limiting agents specific action

Answer 31

``` block calcium channels on heart and smooth muscle - myocardial depressant and bradycardic actions, reduce cardiac work verapamil - also exerts class IV anti-arrhythmic activity ```

Question 32

Dihydropyridines specific action

Answer 32

act just on smooth muscle

Question 33

Effect of calcium channel blockers

Answer 33

vasodilatation, improve coronary blood flow | prevents symptoms

Question 34

What are calcium channel blockers used for?

Answer 34

IHD | AF

Question 35

Advantages and disadvantages of rate limiting agents

Answer 35

does not cause reflex tachycardia | but worsens heart failure

Question 36

What else may ps with IHD be prescribed?

Answer 36

ACEIs potassium channel activators - nicorandil Ivabradine antiplatelet drugs - low dose aspirin and clopidogrel statins

Question 37

How does nicorandil work?

Answer 37

combined NO donor and activator of ATP-sensitive K channels | causes hyperpolarisation and vasodilatation

Question 38

How does ivabradine work?

Answer 38

inhibits funny current channels (pacemaker current in SAN) | reduces heart rate

Question 39

How do statins work?

Answer 39

prevents synthesis of cholesterol HMG-CoA reductase inhibitors (first step of synthesis) therefore causes secondary response: up-regulation of hepatic LDL receptors - promotes LDL uptake

Question 40

Example of statin

Answer 40

atorvastatin

Question 41

Problems of statins

Answer 41

rarely causes muscle damage interactions with macrolides (blocks metabolism of simvastatin), grapefruit juice and some calcium channel blockers - interact, use lower dose statin

Question 42

When are statins used?

Answer 42

primary prevention - risk | secondary prevention - already exhibited problem

Question 43

Steps of managing stable angina

Answer 43

GTN assess CV risk - aspirin/clopidogrel, statin, lifestyle, BP, ACEI prevention - beta/calcium channel blocker +/- oral nitrate refractory - dihydropyrimidine, (nicorandil, ivabradine)

Question 44

What combination is fatal?

Answer 44

``` rate-limiting CCB and beta-blocker causes asystole (death) ```