Ischaemic Heart Disease

Question 1

What is the first line investigation for angina?

Answer 1

CT coronary angiography

Question 1

How would you council a patient on Angina?

Answer 1

Angina
This is the term which is used to describe symptomatic chest pain which occurs due to myocardial ischaemia.

In the heart, the coronary circulation fills during diastole. Due to atherosclerosis, over time, the coronary arteries become occluded impeding blood flow to the muscle.

It means areas of myocardium become ischaemic, especially in times of greater oxygen demand, which leads to chest pain.

To counteract this, the body increases sympathetic stimulation which aims to increase cardiac output. But this worsens the issue as it increases O2 demand further.

Hence, when treating angina, the main goals are increasing coronary filling by vasodilation, increasing diastolic time and reducing myocardial oxygen demand.

Question 2

What is 2nd line investigations for angina?

Answer 2

2nd line is non-invasive functional imaging to look for reversible myocardial ischaemia

Question 3

What is the investigation for unstable angina?

Answer 3

In unstable angina, generally invasive angiography is performed, although performing a CTCA is reasonable

Question 4

What is the management for stable angina?

Answer 4

1) Prognostic medications to reduce risk of MI – aspirin and a statin

2) Initial symptom relief – glyceryl trinitrate spray

3) Longer term – 1st line is B-blocker or Ca2+ channel blocker (verapamil or diltiazem)

If still symptomatic, give dual therapy with beta-blocker and dihydropyridine

If dual therapy not tolerated, add nicorandil or ivabradine or long-acting nitrate

Question 5

What is prinzmetal angina due to?

Answer 5

coronary artery vasospasm

Question 6

What is the management of angina?

Answer 6

Calcium channel blockers (dyhydropyridine) with optional long-acting nitrates

PRN Glyceryl trinitrate spray to relieve symptom

Question 7

What is ischaemic heart disease?

Answer 7

a complex process that develops over a long time called ATHEROSCLEROSIS resulting in myocardial ischaemia

• AKA coronary artery disease

Question 8

What is the process of atherosclerosis?

Answer 8

1. Initial endothelial dysfunction is triggered by factors eg smoking, HTN and hyperglycaemia
2. This causes changes in the endothelium due to pro-oxidants and proliferation as well as decreased NO bioavailability
3. Fat infiltrates into the subendothelial space via LDL particles
4. monocytes migrate and differentiate into macrophages which phagocytose LDL forming foam cells
   5.- smooth muscle proliferates and migrates from the tunica media into the tunica intima > fibrous plaque covering the fatty plaque

Question 9

What are the 2 complications of ischaemic heart disease?

Answer 9

1. gradual narrowing of arteries > decreased blood flow + oxygen supplying the myocardium at times of increased demand > ANGINA
2. sudden plaque rupture from the endothelium > sudden total occlusion of an artery > no blood + oxygen supplying the myocardium > MI

Question 10

What are the 2 components of IHD?

Answer 10

1. Stable angina
2. Acute coronary syndrome

Question 11

Name 9 modifiable risk factors of IHD?

Answer 11

1. Smoking
2. Cholesterol (elevated LDL, low HDL)
3. Arterial hypertension
4. Diabetes
5. Physical inactivity
6. Diet
7. Stress
8. Fibrinogen and factor VII

Question 12

What are non-modifiable risk factors of IHD?

Answer 12

Family history of premature CAD
<55 yrs for male
<65 yrs for female
Age and gender:
Male ≥ 45 years
Female ≥ 55 years
Genetic factors: operate in hyperlipidemia, plasma fibrinogen concentration and other coagulation factors, some of which are modifiable by lifestyle changes