Angina Flashcards
What is angina?
When there is a mismatch between blood supply and demand in stable coronary artery disease = myocardial ischaemia = pain (angina).
Ischaemic metabolites i.e. adenosine stimulate pain.
What are the risk factors for angina?
Hypertension Diabetes Hyperlipidaemia Sedentary lifestyle Obesity Smoking Family hx Age
The diagnosis of angina is based on clinical hx. Angina symptoms can be defined into 3 categories: classical angina, atypical angina and non-angina chest pain.
Describe the 3 categories above.
Classical angina characterised by chest pain:
=> Heavy, tight or gripping central or retrosternal pain, may radiate to jaw and/or arms
=> Pain occurs with exercise or emotional stress
=> Pain eases with rest or with GTN
Atypical angina described as chest pain with 2/3 symptoms above.
Non-angina chest pain described as chest pain with 1/3 symptoms above.
Angina can be classified into 4 types. Describe the classification of stable angina.
- Stable angina can be classified into 4 categories:
Class I : Angina with strenuous activity only
Class II : Angina during normal activity i.e. walking up the hill & mild limitation of activities
Class III : Angina with low level of activity e.g. walking 50-100m & marked limitation of activities
Class IV : Angina at rest or with any level of exercise
What is unstable angina?
Angina of recent onset (<24h) or rapid deterioration of previous stable angina with symptoms occurring at rest => acute coronary syndrome
What is refractory angina?
Chronic condition (>3months) in patients with severe coronary artery disease who cannot undergo revascularisation and angina is not controlled by medical therapy.
Reversible myocardial ischaemia = cause of symptoms
What is vasospastic or variant (Prinzmetal’s) angina?
Angina that occurs without any stimulation, usually at rest as a result of coronary artery spasm.
More common in women.
Characteristically, ST elevation on ECG during pain
What is microvascular angina?
Exercise induced angina but normal or unobstructed coronary arteries seen on coronary angiogram.
Intracoronary acetylcholine may cause coronary spasm - highly symptomatic and difficult to treat.
But good prognosis
How do you examine for angina?
No abnormal findings in angina but signs which suggest anaemia, thyrotoxicosis or hyperlipidaemia i.e. corneal arcus, xanthelasma or tendon xanthoma should be noted.
Important to exclude aortic stenosis i.e. slow-rising carotid impulse and ejection systolic murmur radiating to the neck) as cause of angina.
BP measured to identify co-existant hypertension
BMI or waist circumference measured
Which investigations should be carried out in patients with suspected angina?
Lab tests: FBC Thyroid function test Fasting glucose & HbA1c Fasting lipid profile GFR Troponin if unstable
12 lead ECG:
Exclude coronary syndrome, pathological Q waves, left ventricular hypertrophy, left bundle branch block
Echocardiography: Regional wall abnormalities Left ventricular ejection fraction Diastolic function Alternative causes of chest pain
Ambulatory ECG:
Paroxysmal arrhythmia
Vasospastic angina
Chest x-ray:
Atypical presentation
Pulmonary disease
Heart failure
Patients without known coronary artery disease presenting with chest pain can be categorised as having typical angina, atypical angina or non-angina chest pain.
How are these patients investigated?
Patients with typical, atypical or non-angina chest pain but with ST changes or Q waves referred for 64-slice CT coronary angiography (CTCA).
If results from CTCA inconclusive, patient referred to non-invasive functional tests (SPECT, stress ECHO, stress MRI)
If stable angina cannot be diagnosed in patients with known coronary artery disease, patient should be referred for non-invasive functional tests
Patient with non-angina chest pain (i.e. continuous pain, unrelated to exertion, worsened by respiration or assoc. with dizziness, palpitations or difficulty swallowing) and a normal ECG => consider alternative diagnosis
What is the initial (medical therapy) management of stable angina?
Lifestyle modifications
Short-acting nitrates (GTN spray)
Secondary prevention:
Beta-blocker or calcium-channel blocker
What is the alternative if beta blocker and calcium channel blocker is not tolerated or contraindicated in the patient?
Long acting nitrate i.e. Ivabradine, Nocorandil, Ranolazine
How do you manage a patient that is still symptomatic on beta-blockers?
Either switch to calcium-channel blocker or add a calcium channel blocker on top of beta-blocker.
What is the next step in management if the patient still has symptomatic angina on two anti-anginas drugs?
Consider for revascularisation
PCI: single vessel disease ; multi-vessel <65 years ; suitable anatomy
CABG: Unsuitable anatomy ; multi-vessel disease >65 years ; diabetes
