Angina pectoris Flashcards
How does NICE define anginal pain?
NICE defines anginal pain as the following:
- constricting discomfort in the front of the chest, or in the neck, shoulders, jaw or arms
- precipitated by physical exertion
- relieved by rest or GTN in about 5 minutes
=> patients with all 3 features have typical angina
=> patients with 2 of the above features have atypical angina
=> patients with 1 or none of the above features have non-anginal chest pain
What features present in a patient’s history would make angina a less likely diagnosis?
- Pain that is continuous, pleuritic or worse with swallowing
- Pain that is associated with palpitations, dizziness or tingling
What are the causes of angina?
1. Atheroma - most common Rarely: 2. Anaemia 3. Coronary artery spasms 4. Aortic stenosis 5. Tachyarrhythmias 6. Hypertrophic cardiomyopathy 7. Arteritis/ small vessel disease
What are the different types of angina?
- Stable angina => Induced by effort, relieved by rest. Good prognosis
- Unstable angina => Angina of increasing frequency or severity. Occurs on minimal exertion or at rest. Associated with a higher risk of MI
- Decubitus angina => Precipitated by lying flat
- Variant/ prinzmetal angina => Caused by coronary artery spasm
What investigations would you carry out in a patient who has symptoms consistent with typical/ atypical angina OR ECG changes in whom stable angina cannot be excluded by clinical assessment alone?
- CT Coronary angiography - first line
- Non-invasive functional imaging (look for reversible myocardial ischaemia) - 2nd line
- Invasive coronary angiography
What are some examples of non-invasive functional imaging?
- Myocardial perfusion scintigraphy with single photon emission computed tomography (MPS with SPECT)
- Stress echocardiography
- First pass contrast enhanced magnetic resonance (MR) perfusion
- MR imaging for stress induced wall motion abnormalities
What investigations would you carry out in a patient with typical angina with previously proven IHD?
Treat as stable angina
For further confirmation, use non invasive testing like exercise ECG
What TESTS would you carry out in a patient with angina?
- ECG - usually normal but may show ST depression; flat or inverted T waves; signs of past MI
- Blood tests - FBC, U&Es, TFTs, lipids, HbA1c
- Consider echo and CXR
- Further Ix needed to confirm diagnosis of IHD
What investigations would you do to confirm the diagnosis of IHD?
- Exercise ECG - to assess ischaemic ECG changes
- Angiography - either using cardiac CT with contrast or transcatheter angiography
- Functional imaging
How would you go about investigating non-anginal chest pain?
Does patient have ischaemic changes on 12 lead ECG?
Yes - investigate as per typical and atypical angina
No - no further Ix for IHD at this point. Ensure alt diagnoses are adequately explored
What are the broad principles in the management of angina?
- Address exacerbating factors - anaemia, tachycardia (eg fast AF), thyrotoxicosis
- Secondary prevention of cardiovascular disease
a. Stop smoking; exercise; diet; optimise HTN and diabetes control
b. 75mg aspirin daily
c. Address hyperlipidaemia
d. Consider ACEi eg if diabetic - PRN symptom relief - GTN spray or sublingual tabs.
- Anti-anginal medication
- Revascularisation - considered when optimal medical therapy proves inadequate
a. PCI
b. CABG
What are the NICE guidelines regarding anginal drugs?
- All patients should receive aspirin and a statin in the absence of any contraindication
- Sublingual glyceryl trinitrate to abort angina attacks
- Either a beta-blocker or a calcium channel blocker first-line
=> If a calcium channel blocker is used as monotherapy a rate-limiting one such as verapamil or diltiazem should be used. If used in combination with a beta-blocker then use a long-acting dihydropyridine calcium-channel blocker (e.g. modified-release nifedipine).
=> Remember that beta-blockers should not be prescribed concurrently with verapamil (risk of complete heart block)
- If there is a poor response to initial treatment, then medication should be increased to the maximum tolerated dose (e.g. for atenolol 100mg od)
- If a patient is still symptomatic after monotherapy with a beta-blocker add a calcium channel blocker and vice versa
- If a patient is on monotherapy and cannot tolerate the addition of a calcium channel blocker or a beta-blocker then consider one of the following drugs: a long-acting nitrate, ivabradine, nicorandil or ranolazine
- If a patient is taking both a beta-blocker and a calcium-channel blocker then only add a third drug whilst a patient is awaiting assessment for PCI or CABG
MoA of Ivabradine?
- A new class of anti-anginal drug which works by reducing the heart rate with minimal impact on BP
- Acts on the If (‘funny’) ion current which is highly expressed in the sinoatrial node, reducing cardiac pacemaker activity
- Patients must be in sinus rhythm
- Adverse effects: visual effects, particular luminous phenomena, are common. Headache. Bradycardia, due to the mechanism of action, may also be seen
There is no evidence currently of superiority over existing treatments of stable angina
MoA of Ranolazine?
- Inhibits late Na+ current
2. Caution if HF, elderly, weight <60kg or prolonged QT interval
MoA of Nicorandil?
- A K+ channel activator
2. CI: acute pulmonary oedema, severe HTN, hypovolaemia, LV failure
