Stable Angina Flashcards
What is angina?
A discomfort in the chest and/or adjacent areas associated with myocardial ischaemia but without myocardial necrosis.
What is the pathophysiology of myocardial ischaemia?
Myocardial supply and demand mismatch.
A reduction in coronary artery blood flow to the myocardium (obstructive atheroma).
What is the most common cause of angina?
Coronary atheroma.
Increased myocardial O2 demand (due to rising HR and BP - exercise, stress, after a large meal) causes an increase in coronary blood flow.
Obstruction leads to myocardial ischaemia and angina symptoms.
What features of pain are used to diagnose angina?
Site - retrosternal (watch for gestures).
Character - tight, pressurised, heavy.
Radiation - neck, jaw, arms.
Aggravation - exertion, stress.
Relief - GTN or rest.
What features do patients present with that make angina less likely?
Sharp pleuritic/pericardial pain.
Associated with movement or respiration.
Localised, no pattern, after exercise, long.
Superficial.
When would myocardial ischaemia present with no chest pain?
More often in the elderly and diabetic.
Reduced pain sensation.
Accompanied with SOB, fatigue, near syncope.
What are differential diagnoses for angina?
CVS - aortic dissection, pericarditis.
Respiratory - pneumonia, pleurisy, peripheral pulmonary emboli.
Muscle spasms, peptic ulcers, pancreatitis.
How is the severity of angina measured?
I - Symptoms only on significant exertion.
II - Slightly limitation of ordinary activity, symptoms on walking >1 flight of stairs.
III - Marked limitation, symptoms on walking 1 flight of stairs.
IV - Symptoms on any activity.
What are the risk factors of angina?
Age, male, family history, post-menopausal females, arterial disease, smoking, exercise, diet.
Diabetes, hypertension, hyperlipidaemia (control reduces CV risk).
What are the cardiovascular signs of angina?
Xanthelasma and corneal arcus - hypercholesterolaemia.
AAA, arterial bruits, reduced or absent pulses.
Tachycardia and tremors - hyperthyroidism.
Ejection systolic murmur - aortic stenosis.
Pansystolic murmur - mitral regurgitation.
Basal crackles, high JVP - heart failure.
What are the investigations of angina?
Bloods - FBC, lipids, glucose, electrolytes, LFTs.
CXR - can show other causes of chest pain.
ECG - most are normal; can show Q waves (prior MI) or ST depression (LVH).
ETT - can confirm diagnosis.
Myocardial perfusion imaging.
CT, coronary/invasive angiography.
Cardiac catheterisation.
What is an ETT?
Exercise Tolerance Test - relies on the ability to walk long enough to produce CV stress.
Positive test - typical symptoms, ST-segment depression.
Negative test - doesn’t exclude significant coronary atheroma, but a good prognosis.
What is myocardial perfusion imaging?
Radionuclide tracer injected at peak stress on one occasion and at rest on another, images obtained from both. Compare.
Tracer only seen at rest - ischaemia.
Tracer not seen on either - infarction.
Expensive, involves radioactivity, used when ETT is not available.
When would you use an invasive angiography?
Early or strongly positive ETT - suggests multi-vessel disease.
Angina refractory to medical therapy.
Diagnosis not clear after non-invasive tests.
Young cardiac patients, due to work/life effects.
Occupation or lifestyle with risk.
What is cardiac catheterisation?
Defines coronary anatomy; distribution and nature of atheromatous disease.
Enables decision for treatment options - medication, PCI, angioplasty, CABG.
