SIHD and Angina

Question 1

What is angina (pectoris)?

Answer 1

Cardiac chest pain: a discomfort in the chest and/or adjacent areas associated with myocardial ischaemia but without myocardial necrosis

Question 2

What causes angina?

Answer 2

A mismatch between oxygen supply and metabolites to the myocardium and the demand for them

Question 3

What is the cause for the mismatch between oxygen/metabolite supply and the demand?

Answer 3

A reduction in the coronary blood flow to the myocardium, most commonly caused by obstructive coronary atheroma

Question 4

What are the less common causes of angina@

Answer 4

Anaemia and increased myocardial demand (Left ventricular hypertrophy and thyrotoxicosis)

Question 5

At what times will myocardial oxygen demand increase?

Answer 5

During exercise, anxiety/emotional stress, cold weather and after a large meal

Question 6

What are the characteristics of angina?

Answer 6

Site: retrosternal
Character: tight band/pressure
Radiation: neck, jaw and arms
Exacerbating Factors: exertion, emotional stress etc.
Relieving Factors: rapid improvement with GTN or physical rest

Question 7

What features of the pain make angina unlikely?

Answer 7

Pain that is sharp/stabbing, associated with body movements, very localised, superficial, without pattern, begins some time after exercise or lasts for hours

Question 8

Besides chest pain, what other symptoms may myocardial ischaemia present with on exertion?

Answer 8

Breathlessness, excessive fatigue and near syncope

Question 9

What does stage 1 on the CCS scale of angina severity represent?

Answer 9

Symptoms are only on significant exertion

Question 10

What does stage 2 on the CCS scale of angina severity represent?

Answer 10

Slight limitation of ordinary activity. Symptoms on walking 2 blocks or more than one flight of stairs

Question 11

What does stage 3 on the CCS scale of angina severity represent?

Answer 11

Marked limitation. Symptoms on walking 1-2 blocks or 1 flight of stairs

Question 12

What does stage 4 on the CCS scale of angina severity represent?

Answer 12

Symptoms on any activity - getting washed/dressed causes symptoms

Question 13

What are the non-modifiable risk factors for coronary artery disease

Answer 13

Age, gender, creed, family history and genetic factors

Question 14

What are the modifiable risk factors for coronary artery disease?

Answer 14

Smoking, lifestyle - exercise and diet, diabetes mellitus (control reduces risk), hypertension (control reduces risk) and hyperlipidaemia (lowering reduces risk)

Question 15

What are the signs that help diagnose stable angina?

Answer 15

Tar staining, obesity, xanthalasma, corneal arcus, hypertension, abdominal aortic aneurysm bruits, absent or reduced peripheral pulses, diabetic/hypertensive retinopathy

Question 16

What sign would you expect to see if anaemia was an exacerbating/associated condition?

Answer 16

Pallor

Question 17

What sign would you expect to see if hyperthyroidism was an exacerbating/associated condition?

Answer 17

Tachycardia, tremor and hyper-reflexia

Question 18

What sign would you expect to see if aortic stenosis was an exacerbating/associated condition?

Answer 18

An ejection systolic murmur and plateau pulse

Question 19

What sign would you expect to see if heart failure was an exacerbating/associated condition?

Answer 19

Basal crackles, pansystolic murmur of mitral regurgitation elevated JVP and peripheral oedema

Question 20

What blood tests would be routinely done for someone with suspected angina?

Answer 20

FBC, lipid profile, fasting glucose, electrolytes, liver and thyroid tests

Question 21

Why might a CX-Ray be done?

Answer 21

It often helps show other causes of chest pain and pulmonary oedema

Question 22

What may be seen on the ECG?

Answer 22

Evidence of prior MI e.g. pathological Q waves or evidence of LVH e.g. high voltages, lateral ST segment depression or ‘strain pattern’

Question 23

What investigations can be used to diagnose stable angina?

Answer 23

ECG, exercise tolerance test, CT coronary angiography and myocardial perfusion imaging

Question 24

What comparison does myocardial perfusion imaging allow?

Answer 24

It allows comparison between the images taken at rest and during stress

Question 25

During myocardial perfusion imaging, what does seeing the tracer at rest but not after stress suggest?

Answer 25

Ischaemia

Question 26

What does not seeing the tracer at rest or during stress on myocardial perfusion imaging suggest?

Answer 26

That there are areas of infarction

Question 27

Under what circumstances would an invasive angiography be performed?

Answer 27

If there is an early or strongly positive ETT, angina refractory to medical therapy, the diagnosis is not clear after non-invasive tests, they are a young cardiac patient due to work/life effects or they have a high risk occupation/lifestyle e.g. drivers

Question 28

How is a coronary angiogram performed?

Answer 28

It is mostly done under a local anaesthetic. A cannula is passed into the femoral/radial artery and the coronary catheters are passed to the aortic root. They are then introduced into the ostium of the coronary arteries and radio-opaque contrast is injected down the coronary arteries and visualised on X-Ray

Question 29

What are the treatment strategies for stable angina?

Answer 29

Address the risk factors (BP, cholesterol etc.), medical treatment (drugs to reduce disease progression and symptoms) and revascularisation (PCI and CABG) if the symptoms are not controlled

Question 30

What types of medications are used to reduce the disease progression?

Answer 30

Statins (if cholesterol levels are high), ACE inhibitors (if increased CV risk and atheroma) and aspirin

Question 31

What medications are used to relieve the symptoms of stable angina?

Answer 31

Beta-blockers, CCBs, and Ik channel blockers lower heart rate to <60bpm.
CCBs and nitrates (GTN) produce vasodilation.
Potassium channel blockers helpful in ‘pre-conditioning’

Question 32

How does PCI work?

Answer 32

It uses a balloon and stent to squash the atheromatous plaque into the walls and open the artery

Question 33

What drugs should be prescribed if a stent has been used?

Answer 33

Aspirin and clopidogrel taken together

Question 34

Which patients are more likely to have prognostic benefit from CABG?

Answer 34

Those with: >70% stenosis of the left mains stem artery, significant proximal three vessel coronary artery disease or two vessel coronary artery disease that includes significant stenosis of the proximal left anterior descending coronary artery and who have ejection fraction <50%