Week 126 Chronic Stable Angina Flashcards
Name some non-ischaemic cardiovascular Ddx for someone with chest pain
Aortic dissection
Pericarditis
What is the definition of stable angina?
What is it’s cause?
Chest pain/discomfort which is caused by reversible ischaemia to the myocardium, brought on by increased work load and relieved by rest. Reversible ischaemia is usually due to CAD
Name some pulmonary causes of chest pain (4)
PE
PneumoTx
Pneumonia
Pleuritis
Name some GIT causes of chest pain (9 listed)
Oesophagitis Oesophageal spasm Reflux Biliary colic Cholecystitis Choledocholithiasis Cholangitis Peptic ulcer Pancreatitis
Name some chest wall causes of chest pain (5 listed)
Costochondritis Fibrositis Rib fracture SC arthritis Herpes zoster
Name 4 life threatening causes of chest pain
MI
PE
Tension pneumoTx
Dissecting aortic aneurism
What is a fatty streak in an artery composed of?
Lipid (cholesterol)
Macrophages
T lymphocytes
What makes up the fibrous cap of an atherosclerotic plaque?
SM cells
Elastin
Collagen
Proteoglycans
What is the outcome of an imbalance of demand/supply in the myocardium?
Metabolic changes
Diastolic and contractile dysfunction
Electrophysiological abnormalities
Symptoms…angina
What are most MIs caused by?
Plaque rupture rather than occlusion of the coronary arteries
How can anaemia lead to angina?
Not enough oxygen to the myocardium
Name some non-atherosclerotic causes of CAD (note - very uncommon, 6 listed)
Congenital- anomalous origin of the coronary arteries
Arteritis - associated with autoimmune diseases like SLE
Coronary etasia
Radiotherapy
Syndrome X
Prinzmental’s angina
How many classes of angina are there?
4
What is Class 1 angina?
Angina caused by strenuous/protracted excercise
What is Class 2 angina?
Slight limitation with vigorous physical activity eg walking up a hill
What is Class 3 angina?
Marked limitation with symptoms during activities of daily living
What is Class 4 angina?
Inability to perform ADL with angina at rest
Why is there a problem with pre-testing asymptomatic individuals?
There’s a high rate of false positives
If the chest pain is well localised, what is the most likely cause?
Pleuritic in origin
Which feature on an ECG is an important predictor of acute coronary syndrome?
New Q waves
What feature may be seen on an ECG of a pt with angina?
ST elevation/depression
Why would a CXR be useful to do in a pt with angina?
To rule out any other causes eg pulmonary
What is the target heart rate when doing an ETT?
220- age in years
When is an ETT stopped?
If marked ST depression or sustained arrythmias present on ECG
What are the absolute contraindications for ETT? (7 listed)
MI Unstable angina Uncontrolled arrhythmias Symptomatic heart failure/aortic stenosis Acute PE Acute myocarditis Acute dissection
Which drug is used in a stress ECHO?
Dobutamine
Which stress agent is used when performing myocardial perfusion testing?
Adeosine
Which scan has better spatial resolution than myocardial perfusion testing?
PET scan
Which anatomical test/investigation is useful to visualise plaques?
CT coronary angiography
Which test is useful to determine the histology of atherosclerotic plaques in the coronary arteries?
Intravascular ultrasound
What is the medical treatment for angina? (Name 4 of 10 listed)
Beta blockers Anti platelets Statins ACE inhibitors Nondihydropyridine calcium channel blocker Ivabradine Dihydropyridine ca agonists Nitrates Nicorandil Ranolazine ....ect
Which channels does the drug Ivabradine inhibit? What is the effect of this?
‘Funny’ channels which are associated with the SA and AV nodes - slows HR
How does hypertrophic cardio myopathy lead to angina?
Myocardium is thicker and therefore requires a higher supply of oxygen
What is the term to describe: lack of oxygen resulting in decrease of aerobic oxidative respiration resulting in cell injury?
Hypoxia
What is the term used to describe: Lack of blood supply from a stenotic/occluded artery or reduced venous drainage resulting in lack of oxygen and essential metabolites?
Ischaemia
Which causes cell injury more rapidly:
Hypoxia or ischaemia?
Ischaemia
Which term describes:
irreversible cell damage due to ischaemia and hypoxia?
Infarction
Name some causes of cell injury (7 listed)
Hypoxia Infections Metabolic/nutritional Trauma Drugs/chemicals Autoimmune Genetic causes
What are the 4 features in the pathophysiology of cell injury?
- Decreased ATP
- Membrane damage
- Increased intracellular calcium
- Increased oxygen derived free radicals
What is the result of decreased Na/K pump in cell injury?
Influx of calcium and water. Efflux of potassium leading to ER swelling and cell swelling -> loss of microvilli etc
What is the result of increased anaerobic glycolysis in cell injury?
Decreased glycogen and decreased pH leading to clumping of chromatin
Decrease in synthesis of what leads to membrane damage?
Phospholipid synthesis1
What is the result of an increase in intracellular calcium?
Activation of phospholipases, proteases and ATPase which breaks down the cell membrane and cytoskeleton and decreases ATP
What is ischaemia-reperfusion injury?
When blood is restored to ischaemic tissues resulting in an inflammatory response and damage of cellular proteins, DNA and the plasma membrane by the re-introduction of oxygen intracellularly
What are the complications of atherosclerosis? (4 listed)
Gradual narrowing of arteries
Ulceration of the plaques
Rupture/fissuring of the plaques
Superimposed thrombosis
What are the main differences between a stable and an unstable plaque?
Stable: concentric narrowing; rich in stroma and SM
Unstable: Eccentric narrowing; rich in lipids, SM with inflammation + endothelial cell injury
What are the major risk factors for atherosclerosis?
Smoking
HTN
Hyperlipidaemia
Diabetes
Name some complications of MIs (7 listed)
Sudden cardiac death Arrhythmias Left ventricular failure Ventricular hypertrophy Papillary muscle fibrosis Mural thrombosis Ventricular aneurism
