Stable Angina

Question 1

What causes angina?

Answer 1

A narrowing of the coronary arteries reduces blood flow to the myocardium (heart muscle).

During times of high demand such as exercise there is insufficient supply of blood to meet demand.

This causes symptoms the symptoms of angina, typically constricting chest pain with or without radiation to jaw or arms.

Question 2

When is angina considered stable?

Answer 2

Symptoms are always relieved by rest or glyceryl trinitrate (GTN)

Question 3

When is angina considered unstable?

Answer 3

Symptoms come on randomly whilst at rest, and this is considered as an Acute Coronary Syndrome

Question 4

What is the gold standard diagnostic investigation in the diagnosis of angina?

Answer 4

CT coronary angiography

Involves injecting contrast and taking CT images timed with the heart beat to give a detailed view of the coronary arteries, highlighting any arteries.

Question 5

What investigations should be carried out?

Baseline
1st line
Second line

Answer 5

Bloods and ECG

1st line - CT coronary angiography is indicated for atypical or typical angina pain or if ECG shows ischaemic changes in chest pain with <2 angina features.

2nd line - Myocardial perfusion SPECT
Stress ECHO
MRI for regional wall motion abnormalities

Question 6

What is the management plan for angina?

Answer 6

R – Refer to cardiology (urgently if unstable)
A – Advise them about the diagnosis, management and when to call an ambulance
M – Medical treatment
P – Procedural or surgical interventions

Question 7

What are the three aims of medical management in angina?

Answer 7

Immediate Symptomatic Relief
Long Term Symptomatic Relief
Secondary prevention of cardiovascular disease

Question 8

What is given for immediate symptomatic relief in angina?

Answer 8

Glyceryl trinitrate- GTN - spray

Question 9

How should GTN spray be used?

Answer 9

As needed for relief during episode
Take GTN, repeat after 5 mins - if patient is still in pain after repeat dose, call an ambulance

GTN causes vasodilation and helps relieves the symptoms

Question 10

What is used for long term relief of angina?

Answer 10

Beta blocker (e.g. bisoprolol 5mg once daily) or;
Calcium channel blocker (e.g. amlodipine 5mg once daily)

Can be taken in combination if do not work alone

Question 11

What is used for secondary prevention of angina?

Answer 11

Aspirin (i.e. 75mg once daily)
Atorvastatin 80mg once daily
ACE inhibitor
Already on a beta-blocker for symptomatic relief.

Question 12

What procedures can be used for the treatment in angina?

Answer 12

Percutaneous Coronary Intervention (PCI) with coronary angioplasty

Coronary Artery Bypass Graft (CABG)

Question 13

What happens in PCI?

Answer 13

Dilating the blood vessel with a balloon and/or inserting a stent)

Question 14

Who is PCI offered to?

Answer 14

Patients with “proximal or extensive disease” on CT coronary angiography.

This involves putting a catheter into the patient’s brachial or femoral artery, feeding that up to the coronary arteries under xray guidance and injecting contrast so that the coronary arteries and any areas of stenosis are highlighted on the xray images.

Question 15

Who is CABG offered to?

Answer 15

Patients with severe stenosis

Question 16

What does CABG involve and how does the recovery and complications compare to that of PCI?

Answer 16

Open chest along the sternum, taking a graft vein from the patient’s leg (usually the great saphenous vein) and sewing it on to the affected coronary artery to bypass the stenosis.

The recovery is slower and the complication rate is higher than PCI.

Question 17

First line medical treatment

Answer 17

Conservative management - lifestyle measures and secondary prevention medication i.e. aspirin, statin

GTN AND beta-blocker or rate-limiting calcium channel blocker

If the patient is unable to tolerate a beta blocker, a calcium channel blocker should be tried and vice versa.

Question 18

Second line medical treatment

Answer 18

Second line management is to combine a beta blocker and long-acting dihydropyridine calcium channel blocker.

Question 19

3rd line medical treatment

Answer 19

A 3rd medication should only be added if the patient is symptomatic despite 2 anti-anginal drugs

. Coronary angiography should be arranged unless contraindicated as PCI may be required.

ACE-inhibitors for patients with diabetes and hypertension should be considered.

Question 20

Who should beta blockers be avoided in?

Answer 20

Patients with asthma as can cause bronchoconstriction

Question 21

Pathophysiology of angina

Answer 21

Imbalance between oxygen supply (decreased coronary blood flow) and oxygen demand (increased myocardial oxygen consumption), which leads to a decrease in the oxygen supply/demand ratio and myocardial hypoxia.

The decreased flow can result from a blood clot (thrombus) that occludes a coronary artery.

Question 22

What is verapamil an example of?

Answer 22

Rate limiting calcium channel blocker

RLCCBs cannot be used with beta blockers due to the risk of brachycardia and heart block

If stable angina not managed with verapamil, add isosorbide mononitrate which is Nitrate

Question 23

What are beta blockers contraindicated with?

Question 24

What combo of beta blockers and CCB is best?

Answer 24

Bisoprolol and Felodipine

When giving a combination of beta-blockers and calcium-channel blockers, it is vital that the latter is a dihyropyridine calcium channel blocker (e.g. Amlodipine or Felodipine). Beta-blockers and non-dihydropyridine should not be given together as they are both negatively inotropic and their effects are additive. This can lead to marked bradycardia and increase the risk of atrioventricular block.