Acute Coronary Syndrome Flashcards
How is ACS classified?
- Unstable angina -
- symptoms of prolonged angina
- Normal ECG and troponin levels
- Non ST elevation ACS
- Symptoms of MI
- Raised troponin levels
- ECG: NO St elevation BUT might have St depression/Twave inversion/no changes
- ST elevation ACS
- Symptoms of MI
- Raised Troponin levels
- ECG: ST elevation
What are the risk factors for ACS?
- NON-MODIFIABLE FOR ATHEROSCLEROSIS
* increase age / male / FHx premature ACS / premature menopause - MODIFIABLE ATHEROSCLEROSIS
* smoking / DM / HTN / dyslipidaemia / obesity / lack of exercise - NON ATHEROSCLEROSIS
* Cocaine use / infected valve / severe anaemia / coronary occlusion / thyrotoxicosis
What are the clinical features of ACS?
- Central crushing chest pain radiating to neck and left arm 2. SOB / pallor / palpitations / nausea & vomiting / sweating / fatigue
What are the DDx of chest pain?
- CARDIOVASCULAR
* acute pericarditis / myocarditis / PE / aortic stenosis / aortic dissection - RESPIRATORY
Pneumonia / pneumothorax
- GASTROLOGY
oesophageal spasm / oesophagitis / GORD / cholecystitis / acute pancreatitis
4. Musculoskeletal chest pain
What are the main investigations for ACS?
1. ECG 12 Lead
ST Elevation, ST depression T wave inversion
2. Cardiac Troponin I & T
Detectable 3 to 6 hours after infarction & peak at 12-24
3. Bloods
CRP (marker acute inflammation), FBC (suspected anaemia), Blood glucose (high incidence ACS w/ hyperglycaemia)
4. Imaging
Echo, CXR, CMR (structural abnormalities for Ddx)
5. Coronary angiography*
(severity on coronary artery disease)
What is the initial treatment for unstable angina and NSTEMI?
1. Aspirin 300mg
- Clopidegrel if aspirin sensitive
2. Fondaparinux if no bleeding risk and coronary angioplasty not planned in next 24h
OR
Heparin if coronary angioplasty likely within 24h or creatinine >256umol
3. Nitrates and morphine for chest pain
NB: NO Oxygen unless desaturated
What is the risk assessment score for unstable angina and NSTEMI?
GRACE score
What is management of low risk patient from GRACE score?
Aspirin 75mg indefinitely
What other emdication should be given to NSTEMi patients?
- Clopidegrel 300mg (continue for 12 months)
2. IV glycoprotein receptor antagonists (e.g. EPTIFIBATIDE or TIROFIBAN) if scheduled for angiography within 96h
What is the MOA of aspirin?
Antiplatelet - inhibits production thrombaxane
What is MOA of clopidegrel?
Antiplatelet - inhibits ADP biding to its platelet receptor
What is MOA of fondaparinux?
Activates antithrombin III ==> potentiates inhibition of coagulation factors Xa
Which vessel and area of heart is involved in V1-V4 ST elevation?
LEFT ANTERIOR DESCENDING
ANTERIOR AREA
Which vessel and area of heart is involved in II, III, aVF ST elevation?
RIGHT CORONARY ARTERY
Inferior area
Which vessel and area of heart is involved in I, V5-6 ST elevation?
LEFT CIRCUMFLEX BRANCH
Lateral Area
What is initial management of STEMI?
- Aspirin 300mg
- GTN spray
- Morphine
- Metaclopramide (anti emetic)
NB: ONLY OXYGEN IF SATS <94%
What is the standard managment of STEMI?
- PCI FIRST LINE TREATMENT
Management before PCI includes
- Clopidegrel (or other antiplatelet)
- Bivalirudin (direct thrombin inhibitor)
- Heparin
What is given if PCI cannot be offered in STEMI?
- Fibronolysis
IF
- Onset within 12h
- PCI no offered w/i 120 mins
What fibronolysis drugs are used and how do they work?
Drugs: ALTEPLASE, TENECTEPLASE, STREPTOKINASE
MOA: Thrombolytic drugs activate plasminogen to form plasmin ==> degrades fibrin ==> breaks up thrombi
What are the contraindications to fibrinolysis?
- Active internal bleeding
- Recent haemorrhage, trauma, surgery
- Coagulation & bleeding disorders
- Stroke < 3 months
- Pregnancy
- Recent head injury
- Severe HTN
What are the side effects of fibrinolysis?
- Haemorrhage
- Hypotension (esp streptokinase)
- Allergic reaction
Other causes of raised troponin?
- Heart failure
- Myocarditis
- Pulmonary Embolism
- Renal fialure
- Severe sepsis
- Supraventricular tachycardia
