Angina

Curriculum Homepage

Video by the author

Unstable Angina

Defined as chest pain on minimal/no exertion, or pain progressing rapidly despite medications.

Urgently refer to cardiology, or admit if pain is severe, at rest, or lasting >10m despite GTN.

15% of people with unstable angina will suffer an MI within a month

Stable Angina

Definition

Three main features

1. Constricting discomfort in the front of the chest, or in the neck, shoulders, jaw or arms
2. Precipitated by physical exertion
3. Relieved by rest or GTN in about 5 minutes

3/3 = typical angina
2/3 = atypical angina
≤1 or none = non-anginal chest pain

LOOK FOR RISK FACTORS. The more the risk factors for CVD, the more the chance of atypical chest pain being angina.

Investigations

Three main reasons to investigate stable angina:

1. To establish the diagnosis
2. Look for risk factors
3. Look for other complications of risk factors

In Primary Care

Examination — BMI, waist circumference, heart sounds

Bloods — FBC, U&Es, TFTs, glucose/HbA1c, lipids

ECG — resting ECG

Thinking they might have angina based on the history and investigations so far? Refer to cardiology.

In Secondary Care

First-line: CT coronary angiography (CTCA)
Second line: ETT, MP SPECT, stress echo/MRI
Third line: invasive angiography

Note ETT is no longer first line due to variable diagnostic accuracy. Invasive angiography is now very much a third-line investigation.

SCOT-HEART trial 2018 — compared usual care vs CTCA with subsequent management — latter led to 40% RRR in death/MIs at 5y
https://www.nejm.org/doi/full/10.1056/NEJMoa1805971

Management

Refer all patients to the chest pain clinic or cardiology.

Drug management has two main aims: symptom reduction and CVD risk reduction.

Symptom reduction

GTN spray PRN — all patients

First line: beta blockers (BBs). Aim HR <60 with BBs. Can give in patients with COPD (beware asthma though)
Second line: calcium channel blockers (e.g diltiazem) if BBs not working
Third line: BB + CCBs (e.g amlodipine)

If BBs/CCBs contraindicated or not effective, start one of the following along with whichever one of BB/CCB the patient is able to take:
• ISMN
• Nicorandil
• Ivabradine
• Ranolazine

If ongoing symptoms despite max doses of 2 drugs, refer for PCI/CABG.

Clinical Correlate

Q. Mr X has stable angina and is on maximum-dose beta blockers. Despite this he continues to get symptoms. You decide to add a second medication to his regime. Which of the following will you start?
A. Ranolazine
B. Aspirin
C. Felodipine
D. Ramipril
E. Diltiazem

A. This is a symptomatic patient on max BBs. The next step for symptom reduction would be a CCB. But which one? Remember, beta blockers and rate-limiting CCBs both reduce conduction through the node. Non rate-limiting CCBs are fine to give with BBs however, so the answer is C — felodipine.

Beta blockers + rate-limiting CCBs (like diltiazem) = heart block. Avoid combination.

Risk reduction

Lifestyle advice: the backbone of CVD disease prevention, this will constitute advice on stopping smoking, reducing alcohol to <14U/week, exercising more, and eating healthy.

Medications
Aspirin — unless on clopidogrel for other reasons.

• Add rivaroxaban to aspirin if stable coronary artery disease at high recurrence of risk and low risk of bleeding.

Atorvastatin 80mg.
ACEi if diabetic, CKD, MI, or heart failure with left ventricular systolic dysfunction.

Remember the dose for atorvastatin in primary prevention? 20mg OD instead of 80mg.

Remember the ABC aNd D of angina — everyone needs GTN spray along with
Aspirin, ACEi, Atorvastatin
Beta blockers
CCBs
Nitrates, Nicorandil
DOAC