ACS Flashcards
What does ACS encompass?
Unstable angina
NSTEMI
STEMI
What is the process of atherosclerotic plaue formation?
- Accumulation of LDL cholesterol in inner layers of blood vessels
- Leukocytes adhere to the endothelium and enter the intima, where they combine with lipids to become foam cells
- Artery remodelling, calcification and foam cells cause plaques to form
- Rupture of a plaque causes platelet activation, thrombus formation and coronary artery occlusion
What is a type 1 MI?
MI due to artheromatous plaque formation
What is a type 2 MI?
MI due to hypoxia (increased oxygen demand or decreased supply)
What ECG changes can be seen in unstable angina?
Can be normal
ST depression
T wave inversion
What ECG changes can be seen in NSTEMI?
May be normal
ST depression
T wave inversion
What are the non-modifiable risk factors for ACS?
Age
Male
Family history
South Asian or Afro-Carribean ethnicity
What are the modifiable risk factors for ACS?
Smoking
Diabetes
Hypertension
Hyperlipidaemia
Obesity
Sedentary lifestyle
Recreational drug use
What is the presentation of ACS?
Central, crushing chest pain
Radiation to left arm or neck
Shortness of breath
Sweating
Nausea and vomiting
Palpitations
Anxiety
What are the primary investigations for ACS?
ECG
Troponin - troponin is measured at baseline and 4 hours
What are alternative causes of raised troponin?
CKD
Sepsis
Myocarditis
Aortic dissection
Pulmonary embolism
Where does the left coronary artery correspond to on ECG?
I, aVL, V3-V6
Where does the LAD correspond to on ECG?
V1-V4
Where does the circumflex artery correspond to on ECG?
I, aVL, V5-V6
Where does the right coronary artery correspond to on ECG?
II, III, aVF
Where does the circumflex artery supply?
Left atrium
Posterior aspect of left ventricle
Where does the LAD supply?
Anterior aspect of left ventricle
Anterior aspect of septum
Where does the right coronary artery supply?
Right atium
Right ventricle
Inferior aspect of left ventricle
Posterior septal area
What ECG changes can be seen in a STEMI?
ST segment elevation
New left bundle branch block
What other investigations may be useful in the diagnosis of ACS?
FBC, U&E, LFT, lipids, glucose
CXR to exclude other causes of chest pain
Echocardiogram once stable
What is the initial mangement of ACS?
Oxygen if sats < 94
Morphine
GTN
Aspirin 300mg
What is the GRACE score?
A score that gives the 6 month probability of death after an NSTEMI
- Patients with above 3% are considered for early angiography with PCI
What is the diagnostic investigation for ACS?
Coronary angiography
What is the management of STEMI within 120 minutes?
PCI
What is the management of STEMI after 120 minutes?
Thrombolysis with alteplase/tenecteplase
Unfractionated heparin
What are the early complications of ACS?
Post-MI pericarditis
Ventricular fibrillation (cardiac arrest)
Cardiogenic shock
Mitral regurgitation (secondary to papillary muscle rupture)
Left ventricular wall rupture
What are the late complications of ACS?
Dressler’s syndrome - presents similar to post-MI pericarditis
Heart failure
Left ventricular aneurysm
What is the presentation of Dressler’s syndrome?
Pleuritic chest pain
Low-grade fever
Pericardial rub on auscultation
What is the management of Dressler’s syndrome?
NSAIDs
Prednisolone in severe cases
What is the presentation of left ventricular aneurysm post-MI?
Persistent ST elevation and left ventricular failure
What is seen on ECG in a posterior STEMI?
ST depression in leads V1-V3
Tall R waves in leads V1-V3
Upright T waves in V1-V3
Inverted T wave in lead aVR
What is the secondary prevention offered after an MI?
Dual antiplatelet therapy (aspirin + another agent)
ACE inhibitor
Beta-blocker
Statin
What are the second antiplatelets of choice after MI?
Post MI (medically managed) - ticagrelor
Post PCI - prasugrel or ticagrelor
