Week 5: Coronary disease Flashcards
Which GI conditions presents very similarly to MI
Reflux oesophagitis
Why do NSAIDs reduce the anti-platelet effects of aspirin
They are competitive inhibitors at the same binding site on COX-1.
But ibuprofen binds reversibly so has shortlived effects.
Aspirin binds irreversibly.
What are the 3 features of typical angina
- Tight chest pain, may radiate to neck, shoulders, jaw, arms
- Precipitated by exercise
- Relieved by rest/ GTN in 5min
Diagnostic features of myocardial infarction
Troponin >99th percentile +
- Ischaemia symptoms
- ECG indicating ischaemia
- ECG indicating necrosis
- New myocardium loss/ regional wall abnormalities in imaging
When should troponin be measured in hospital
- On admission
2. 6-9h later
What troponin levels indicate an MI
Troponin >99th percentile +
Rise/ fall of >20% on second blood test
Describe the pathophysiology of atherosclerosis
- Lipid is deposited in vascular wall
- Macrophages enter vascular wall and take up lipid, turn into foam cells
- Break down of foam cells releases lipids into vascular wall
- Fibrin, platelets, RBC attracted to site
- Fibroblasts and smooth muscle cells wall off the lipid core
- Plaque grows bigger
How would a cardiac event involving an OCCLUSIVE thrombus show on ECG
- pathological Q waves
- ST elevation
How would a cardiac event involving a SUB-OCCLUSIVE thrombus show on ECG
-ST depression
1st line test used to diagnose angina
CT coronary angiography
How does CT coronary angiography pick up plaques in vessels
Detects the calcium content in the plaques
1st line drugs used to manage angina
Beta blocker or CCB
+GTN spray for episodes of angina
CABG and PCI have pros and cons in different situations. In which situations is CABG preferred?
CABG better for:
- diabetics
- > 60yo
- complex 3 vessel disease
How should a STEMI be managed in the cath lab
- PCI (if eligible)
2. Fibrinolytic drug if PCI cannot be done within 2h
Name some examples of fibrinolytic drugs
Streptokinase/
Alteplase
When not to give a patient a fibrinolytic drug
- If planned PCI
2. If they already had 1 previous dose of fibrinolytic
When to do coronary angiography (with follow on PCI if indicated)
- Presenting after >12h of continuing myocardial ischaemia
- intermediate/high risk of CVD found on GRACE score
How quickly should coronary angiography be done within admission to hospital
Within 96h
What changes on an ECG can indicate ischaemia
New ST changes/
New LBBB
What changes on an ECG can indicate necrosis (death of heart tissue)
Pathological Q waves
Causes of a raised troponin apart from MI
- PE
- Sepsis
- AF
- LV hypertrophy
- Post-operation
What drugs are given within hospital for unstable angina/ NSTEMI
- Aspirin
- Fondaparinux (similar to LMWH)
- Clopidogrel
What does the GRACE score predict
6 month mortality + risk of future CVS events
What is considered a low risk on the GRACE score
less than 3%
What does the CHADVASC score predict
Ischaemic stroke risk
What does the HASBLED score predict
Bleeding risk
What 4 types drugs should a patient be discharged with after an MI
- ACE inhibitor
- Antiplatelets (aspirin + something else)
- Beta blocker
- Statin
Complications post MI
DARTH VADER
Death Arrhythmia Rupture (ventricular free wall/ septum/ papillary muscles) Tamponade Heart failure Valve disease Aneurysm of ventricle Dressler's syndrome (pericarditis) Embolism Regurgitation of mitral valve
What does it mean if:
Troponin on admission <99th percentile + pain >6h
Not an ACS
What does it mean if:
Troponin on admission <99th percentile + pain <6h
Uncertain
Do another troponin after 3h
What does it mean if:
Troponin on admission >99th percentile +
second troponin shows change <3ng/L
Not an ACS
What does it mean if:
Troponin on admission >99th percentile +
second troponin shows change 3-10ng/L or <20%
Uncertain
Do another troponin after 6h
What does it mean if:
Troponin on admission >99th percentile +
second troponin shows change >10ng/L and >20%
ACS
