Stable Ischaemic Heart Disease and Angina Presentation and Investigation Flashcards
What is angina?
Discomfort/pain in the chest and/or adjacent areas associated with myocardial ischaemia but without myocardial necrosis
What is angina a result of?
Mismatch between supply of oxygen and metabolites to the myocardium and the myocardial demand for them
What is angina most commonly due to?
Reduction in coronary blood flow to the myocardium caused by;
obstructive coronary atheroma
coronary artery spasm
coronary inflammation/arteritis
What might cause angina, other than reduction in coronary blood flow to the myocardium?
Reduced oxygen transport e.g. anaemia of any cause
Pathologically increased myocardial oxygen demand e.g. left ventricular hypertrophy or thyrotoxicosis
What is the most common cause of angina?
Coronary atheroma
When does myocardial oxygen demand increase?
In situations where heart rate and blood pressure rise e.g. exercise, anxiety, emotional stress etc.
What is necessary in order for ischaemia to occur?
Lumen has to be reduced by more than 70%
What are the non-modifiable risk factors of stable angina?
Age Gender Creed Family history Genetics
What are the modifiable risk factors of stable angina?
Smoking Lifestyle e.g. diet and exercise Diabetes mellitus Hypertension Hyperlipidaemia
Good control of diabetes, hypertension and hyperlipidaemia reduce the risk
What are the typical characteristics of angina?
Retrosternal site
Described as tight band/pressure/heaviness
May radiate to neck, jaw or down arms
Aggravated by exertion and emotional stress
Relieved by GTN and physical rest
Give some characteristics of pain that make the diagnosis of angina less likely
Sharp/stabbing pain Associated with normal body movements or respiration Very localised Superficial No pattern to pain Begins some time after exercise Lasts for hours
What are some cardiovascular differential diagnoses of chest pain?
Angina
Aortic dissection
Pericarditis
What are some respiratory differential diagnoses of chest pain?
Pneumonia
Pleurisy
Peripheral pulmonary emboli
What are some musculoskeletal differential diagnoses of chest pain?
Cervical disease
Costochondritis
Muscle spasm or strain
What are some gastrointestinal differential diagnoses of chest pain?
Gastro-oesophageal reflux Oesophageal spasm Peptic ulceration Biliary colic Cholecystitis Pancreatitis
If myocardial ischaemia occurs without chest pain, what other symptoms might be present on exercise? Who is this more common in?
Breathlessness
Excessive fatigue for the activity undertaken
Near syncope on exertion
More common in the elderly or those with diabetes mellitus
What is the Canadian Classification of Angina Severity (CCS) grading?
I – ordinary physical activity does not cause angina, symptoms only on significant exertion
II – slight limitation of ordinary activity, symptoms on walking 2 blocks or > 1 flight of stairs
III – marked limitation, symptoms on walking only 1-2 blocks or 1 flight of stairs
IV – symptoms on any activity, getting washed/dressed causes symptoms
What signs might be seen on examination of a patient with angina?
Tar staining Obesity (centripetal) Xanthalasma Hypertension Abdominal aortic aneurysm bruits Absent or reduced peripheral pulses Diabetic retinopathy or hypertensive retinopathy
What signs of exacerbating/associated conditions might be seen on examination of a patient with angina?
Pallor of anaemia
Tachycardia, tremor, hyper-reflexia or hyperthyroidism
Ejection systolic murmur, plateau pulse of aortic stenosis
Pansystolic murmur of mitral regurgitation
Signs of heart failure e.g. basal crackles, elevated JVP, peripheral oedema
What blood tests are relevant in the investigation of stable angina?
FBC Lipid profile Fasting glucose Electrolytes Liver function tests Thyroid function tests
What investigations (other than blood tests) are relevant in the investigation of stable angina?
CXR Electrocardiogram Exercise tolerance test Myocardial perfusion imaging Cardiac catheterisation/coronary angiography
In what percentage of cases of angina will the electrocardiogram be normal?
Over 50%
What might an electrocardiogram show evidence of?
Previous MI e.g. pathological Q waves
Left ventricular hypertrophy e.g. high voltages, lateral ST-segment depression