Stable Ischaemic Heart Disease and Angina

Question 1

Causes of myocardial Ischaemia

Answer 1

1. Obstructive coronary atheroma (very common)
2. Coronary artery spasm (uncommon)
3. Coronary artery inflammation/arteritis (very rare)
   Uncommonly due to
4. Reduced O2 transport due to anaemia of any cause
5. Pathologically increased myocardial O2 demand

Question 2

Modifiable risk factors for coronary artery disease

Answer 2

Smoking
Lifestyle (exercise/diet)
Diabetes Mellitus 
Hypertension
Hyperlipidaemia

Question 3

Non-modifiable risk factors for coronary artery disease

Answer 3

Age
Gender (Male > female)
Creed
Family history/genetics

Question 4

Exacerbating factors for stable angina

Answer 4

Excess myocardial demand

1. Exertion/Exercise
2. Cold Weather
3. Emotional stress
4. Heavy meal

Question 5

Investigations for stable angina

Answer 5

Bloods
CXR
ECG 
ETT
Myocardial Perfusion Imaging
Invasive angiography (most invasive)
Cardiac catheterisation/coronary angiography

Question 6

Characteristics of angina pain

Answer 6

SITE: retrosternal
CHARACTER: tight band/pressure/heaviness
RADIATION: neck and/or into jaw
AGGREVATING FACTORS: exertional/emotional stress
RELIEVING FACTORS: rapid improvement with GTN or physical rest
Other symptoms include:
- Breathlessness on exertion
- Excessive fatigue on exertion for activity undertaken
- Near syncope on exertion

Question 7

Treatment measures for stable angina

Answer 7

General measures: address risk factors: BP, DM, Cholesterol, lifestyle
Drugs: 
-INFLUENCING DISEASE PROGRESSION
1. Statins
2. ACE inhibitors
3. Aspirin
- FOR RELIEF OF SYMPTOMS
1. Beta-blockers
2. IK channel blockers
3. Nitrates (GTN)
4. Ca2+ channel blockers
5. K+ channel activators
Revascularisation:
- Percutaneous Coronary Intervention (PCI)
- Coronary artery bypass grafting (CABG)

Question 8

Acute coronary syndromes

Answer 8

Myocardial Infarction (STEMI/NSTEMI)
Unstable angina pectoris

Question 9

Chronic stable ischemia syndromes

Answer 9

Angina pectoris

Silent ischaemia

Question 10

Two types of myocardial ischaemia

Answer 10

1. Demand Ischaemia (on exertion)

2. Supply ischaemia (at rest)

Question 11

Determinants of myocardial demand

Answer 11

Heart rate
Systolic blood pressure
Myocardial wall stress
Myocardial contractility

Question 12

Determinants of myocardial supply

Answer 12

Coronary artery diameter and tone
Collateral blood flow
Perfusion pressure
Heart rate (duration of diastole)

Question 13

Purpose of drug treatment

Answer 13

Relieve symptoms
Halt disease progress
Regression of disease process
Prevent MI
Prevent death

Question 14

3 major determinants of myocardial oxygen demand (which beta-blockers decrease) are…

Answer 14

Heart rate
Contractility
Systolic wall tension

Question 15

Contraindications for beta blockers

Answer 15

Asthma
Peripheral vascular disease
Raynaud's syndrome
Heart failure (due to dependence on sympathetic drive)
Bradycardia/Heart Block

Question 16

Adverse drug reactions from beta blockers

Answer 16

Tiredness/fatigue
Lethargy
Impotence
Bradycardia
Bronchospasm

Question 17

Contraindications for calcium channel blockers

Answer 17

Never use nifedipine immediate release
Evidence that rapidly acting CCBs (nifedipine) may precipitate acute MI or stroke
Post MI
Unstable angina

Question 18

Adverse drug reactions for (calcium channel blockers)

Answer 18

Ankle oedema (15-20% of patients affected and does not respond to diuretics)
Headache
Flushing
Palpitation

Question 19

Nitro-vasodilators

Answer 19

Glyceryl trinitrate (GTN)
Isosorbide mononitrate
Isosorbide dinitrate

Question 20

Overcome tolerance of nitrates by

Answer 20

1. Giving asymmetric doses of nitrates 8am and 2pm

2. Using sustained release preparation which incorporates a “free nitrate period”

Question 21

Adverse drug reactions of nitrates

Answer 21

Headache - increase dose slowly

Hypotension - GTN syncope

Question 22

Potassium channel openers

Answer 22

Nicorandil

Ivabradine

Question 23

Antiplatelet tablets

Answer 23

Low dose aspirin (75-100mg)
Clopidogrel
Newer agents: prasugrel and ticagrelor

Question 24

Cholesterol lowering agents

Answer 24

Simvastatin
Pravastatin
Atorvastatin

Question 25

New approaches to myocardial ischaemia

Answer 25

Metabolic modulation
Sinus node inhibition
Late Na current inhibition
Preconditioning