Angina

Question 1

Angina: Definition

Answer 1

• A major symptom of IHD/ CHD, characterised by chest pain
• AKA angina pectoris
• Stable: occurs predictably; it happens when you exert yourself physically or feel considerable stress
• Unstable: chest pain that occurs at rest (or with exertion or stress)

Question 2

Angina: Aetiology

Answer 2

• Stable:
  
  • narrowing of the coronary artery from plaque
  • symptoms felt at >70% occlusion
• Unstable:
  
  • likely due to the development of a thrombus from plaque rupture

Question 3

Angina: Risk factors

Answer 3

• Tobacco use
• Diabetes
• High blood pressure
• High blood cholesterol or triglyceride levels
• Family history of heart disease
• Older age
• Lack of exercise
• Obesity

Question 4

Angina: Pathophysiology

Answer 4

• General atherosclerotic pathophysiology
• endothelial damage
  
  • hypertension
  • smoking
  • hyperglycaemia
  • high [blood LDL]
• LDLs (previously just minding their own buisness, floating through the blood and joing their job) enter the tunica intima via damaged site
• damaged endothelial cells express adhesion molecules that capture passing WBCs
• monocytes (previously just moving freely through the blood) are ‘captured’ by damaged endothelium adhesion molecules and enter the tunica intima via damaged site
• monocyte, now macrophage, prod free radicals which oxidise LDLs on contact
• oxidised LDLs attract more WBC to area of tunica intima
• new WBCs consume oxidised LDLs, this stimulates them to prod even more O2 radicals
• This pos feedback loop leads to accumilation of modified LDLs and WBCs
• foam cells are formed (just when WBCs consume loads of LDLs, the lipid content makes them look foamy)
• foam cells die, release their lipid content, other WBCs consume this, become foam cells, cycle continues
• myocytes from tunica media migrate to intima and join the party
• myocyte-foam cell plaque accumilation gains calcium salts and dead cells, hardening it
• endothelium forms over plaque & forms a capsule
• rupture of capsule causes thrombus and maybe embolism

Question 5

Angina: Cinical manifestations: key presentations, other symptoms and signs

Answer 5

• Stable
  
  • central chest pain on exersion/ stress
  • pretty consistent pain (doesn’t get worse)
  • relieved by GTN spray
• Unstable
  
  • new onset chest pain w/o exertion, gets worse quickly
  • GTN doesn’t releive symptoms

Question 6

Angina: Investigations (diagnosis): 1st line, gold standard & other

Answer 6

• resting ECG
• lipid profile (usually raised LDLs)
• CT
• coronary angiography
• cardiac biomarkers (troponin not usually raised as there’s no acute myocardial damage)
• perfusion MRI

Question 7

Angina: DDx

Answer 7

• pericarditis/ myocarditis
• pulmonary embolism
• Pleurisy
• inflammation of pulmonary pleura
• chest infection
• dissection of aorta
• GORD
• MSK cause
• psychological

Question 8

Angina: Management

Answer 8

• Stable (aim to prevent it becoming unstable)
  
  • education about lifestyle factors
  • antiplatelet therapy
    
    • clopidogrel (or another P2Y12 receptor blockers)
    • aspirin
  • medication used to treat high blood cholesterol
    
    • (eg Ezetimibe/ Statins (HMG-CoA reductase inhibitors))
  • antihypertensives
    
    • beta-blockers (slows heart)
    • ACE inhibitors
    • angiotensin-II receptor inhibitors
    • Ca2+ channel blocker
    • diuretics
  • blood sugar control (if needed)
  • Percutaneous Coronary Intervention (PCI, aka angioplasty with stent)
• unstable (for ongoing confirmed unstable angina)
  
  • may have already had percutaneous coronary intervention
  • antiplatelet therapy
  • medication used to treat high blood cholesterol
    
    • (eg Ezetimibe/ Statins (HMG-CoA reductase inhibitors))
  • antihypertensives
    
    • beta-blockers (slows heart)
    • ACE inhibitors
    • angiotensin-II receptor inhibitors
    • Ca2+ channel blocker
    • diuretics
  • medication used to treat high blood cholesterol
    
    • (eg Ezetimibe/ Statins (HMG-CoA reductase inhibitors)