Acute Coronary Syndrome Flashcards
What is acute coronary syndrome?
Any sudden cardiac event suspected or proven to be related to a problem with the coronary arteries
Problems arise due to myocardial ischaemia
e. g.
- Unstable angina
- NSTEMI
- STEMI
What are the risk factors for ACS?
Male Elderly Known heart disease High BP High cholesterol Diabetes Smoker FH of premature heart disease
What can lead to ACS?
Coronary atherosclerosis Coronary vasospasm Coronary dissection Coronary artery embolism Inflammation of coronary arteries Radiotherapy can cause fibrosis/stenosis of coronary arteries
What is the typical diagnosis of an MI?
Detection of cardiac cell death
- myoglobin, troponin, CK-MB
And one of:
- symptoms of ischaemia
- new ECG changes
- evidence of coronary problem on angiography/autopsy
- evidence of cardiac damage from any other test
What type of occlusion may be missed in ACS?
Left circumflex occlusion easily missed - little change on ECG
What investigations might be done in ACS?
Serial ECGs
- consider posterior leads
Blood tests
- check anaemia
- check kidney function, cholesterol, thyroid
Consider angiogram
- ideally within 48 hours
- use risk calculator and common sense
What may be some differential diagnoses in ACS?
Non-cardiac causes of troponin rise
PE
Sepsis
Renal failure
Subarachnoid haemorrhage
How is STEMI/NSTEMI determined and why are they different?
Complete coronary occlusion = ST elevation and pathological Q waves at 3 days
Partial coronary occlusion = No ST elevation and mostly normal Q waves
- can have ST depression, T wave inversion
STEMI vs NSTEMI roughly correlates to transmural vs subendochrondral
What are the different anatomical types of MI?
Depends on area of occlusion
Inferior - RCA
Anterior - LAD
Lateral - Circumflex
Posterior MI - easily missed due to leads
- posterior usually supplied by RCA and so may also see inferior changes
- may be supplied by circumflex
What is the immediate treatment in MI?
STEMI?
- primary PCI
- if over 2 hours from lab, thrombolysis then transfer for PCI
- reperfusion therapy (mechanical (cath) or pharmacological)
NSTEMI
- PCI or CABG
- Antiplatelets
- LMWH/fondaparinux
- GIIb/IIIa receptor blockers
- Statins
- Beta blockers
- IV nitrate
Examples of thrombolytics?
Fibrin specific agents
- alteplase, reteplase, tectenplase
- given as bolus
Non-fibrin specific
- streptokinase
What are the risks associated with thrombolysis?
Bleeding
Don’t give if recent stroke or previous intracranial bleed
Caution if recent surgery, on warfarin, or severe hypertension
Examples of antiplatelets?
ADP recepor antagonists
- ticagrelor
- clopidogrel
- prasugrel
What medications might be given for symptoms? (not disease-modifying)
GTN
- vasodilator
- sublingual or IV
Opiates
- relieves anxiety
- venodilate - may have haemodynamic benefits
What are some complications of ACS?
Arrhythmia Mechanical - cardiogenic shock - myocardial rupture - both lead to death
Other mechanical complications
- valve dysfunction due to papillary dysfunction
- acute ventricular septal defect
