Acute Coronary Syndrome Flashcards
What is acute coronary syndrome?
It is a term used to refer to conditions in which a thrombus from an atherosclerotic plaque blocking a coronary artery
What are the three types of acute coronary syndromes?
Unstable angina
ST elevation myocardial infarction (STEMI)
Non-ST elevation myocardial infarction (NSTEMI)
What is the pathological difference between a STEMI and NSTEMI?
STEMI - complete occlusion of the coronary artery
NSTEMI - partial occlusion of the coronary artery
Which is considered more severe - STEMI or NSTEMI?
STEMI
What two arteries does the left coronary artery divide into?
Circumflex
Left anterior descending (LAD)
What is the route of the circumflex artery?
It curves around the top, left and back of the heart
What two areas does the circumflex artery supply?
Left atrium
Posterior aspect of the left ventricle
What is the route of the left anterior descending artery?
It travels down the middle of the heart
What two areas of the heart does the left anterior descending artery supply?
Anterior aspect of the left ventricle
Anterior aspect of the septum
What is the route of the right coronary artery?
It curves around the right side and under the heart
What four areas does the right coronary artery supply?
Right atrium
Right ventricle
Inferior aspect of the left ventricle
Posterior septal area
What is the main clinical feature of acute coronary syndromes?
Central, constricting chest pain
How long should the chest pain be present for before acute coronary syndromes can be diagnosed?
20 minutes
What six other clinical features are associated with acute coronary syndrome?
Nausea and vomiting
Sweating
Impending doom feeling
S.O.B
Palpitations
Pain radiating to the jaw/arm
Which group of patients tend not to experience chest pain during acute coronary syndromes? What is this known as?
Diabetic
Silent MI
What five investigations are used to diagnose acute coronary syndrome?
ECG scan
Blood tests
CXR
ECHO
CT coronary angiogram
What is the first line investigation used to diagnose acute coronary syndrome?
ECG scan
What two ECG scan features indicate a STEMI diagnosis?
ST elevation
Left bundle branch block
On an ECG, what ST elevation length is required in the chest leads for a diagnosis of STEMI?
> 2mm
On an ECG, what ST elevation length is required in the limb leads for a diagnosis of STEMI?
> 1mm
What three ECG scan features indicate a NSTEMI diagnosis?
ST depression
T wave inversion
Pathological Q waves
What do Q waves indicate on an ECG?
A deep infarct
It is a late sign and demonstrates that the infarct has been present for three days
What area of the heart does the left coronary artery supply?
Anterolateral
What ECG leads would show abnormalities when acute coronary syndrome affects the left coronary artery?
I
aVL
V1 - V6
What area of the heart does the left anterior descending artery supply?
Anterior
What ECG leads would show abnormalities when acute coronary syndrome affects the left anterior descending artery?
V1 - V4
What area of the heart does the circumflex artery supply?
Lateral
What ECG leads would show abnormalities when acute coronary syndrome affects the circumflex artery?
I
aVL
V5 - V6
What area of the heart does the right coronary artery supply?
Inferior
What ECG leads would show abnormalities when acute coronary syndrome affects the right coronary artery?
II
III
aVF
What investigation is conducted when no ST elevation is present on the ECG scan?
Troponin blood tests
What are troponins?
They are proteins which are released when cardiac muscle becomes damaged
How long following cardiac muscle damage are troponin released?
10-12 hrs
What diagnosis is indicated when troponin blood tests are normal?
Unstable angina
What diagnosis is indicated when troponin blood tests are elevated?
NSTEMI
STEMI
What is the main investigation used to differentiate between unstable angina and myocardial infarctions?
Troponin blood test
What seven other conditions cause elevated troponin levels?
Sepsis
Myocarditis
Aortic dissection
Pulmonary embolism
Acute heart failure
Arrhythmias
Chronic kidney failure
What seven other blood tests should be conducted to investigate acute coronary syndrome?
FBC
LFTs
U&Es
TFTs
ESR/CRP
Cholesterol
Glucose
In which arm should we collect blood samples from in suspected acute coronary syndrome cases? Why?
Left
This is due to the fact that the right radial artery is used for PCI
What are the four immediate management options of acute coronary syndrome?
MONA
Morphine
Oxygen
Nitrates
Aspirin
What administration route is used to administer morphine to MI patients? Which dose is used? Which medication is administered with morphine?
IV
5-10mg
Metoclopramide 10mg IV
When do we administer oxygen to patients suffering from acute coronary syndrome?
When the patient’s saturation levels are below 94%
How do we maintain oxygen saturation levels in acute coronary syndrome patients?
High flow 10-15L via Hudson mask
What nitrate is administered to acute coronary syndrome patients?
IV GTN
What dose of aspirin is administered to manage acute coronary syndrome patients?
300mg
How do we manage acute STEMIs that present within 12 hours of onset?
Primary PCI
OR
Thrombolysis
How do we determine whether to conduct primary PCI or thrombolysis?
Primary PCI is the first line treatment option however can only be selected if it is available within 2 hours of presentation
What is PCI?
It involves putting a catheter into the patient’s radial or femoral artery, feeding that up to the coronary arteries under x-ray guidance and injecting contrast to identify the area of blockage
This can then be treated using balloons to dilate the vessels or devices to remove the blockage
A stent is put in to keep the artery open
Which artery is preferred for primary PCI insertion - femoral or radial?
Radial artery
What are the two types of stents that can be used in PCIs?
Drug eluting
Bare metal
What is the first line stent used in PCIs?
Drug eluting
What is thrombolysis?
It involves injecting a fibrinolytic medication that rapidly dissolves the clots
Name three fibronylitic medications
Streptokinase
Altepase
Teneteplase
What is the treatment option selected in NSTEMI patients with a low risk GRACE score?
Percutaneous coronary intervention will be performed at a later date
How do we determine the acute treatment option for stable NSTEMI’s?
We conduct the GRACE score
What is the GRACE score?
This is a scoring system used to estimate the six month risk of death or repeat MI
What are the seven poor prognostic factors of acute coronary syndrome?
Heart failure
Peripheral vascular disease
Reduced systolic blood pressure
Elevated initial cardiac markers
Cardiac arrest on admission
ST segment deviation
Cardiogenic shock
What are the is the most significant poor prognostic factor of acute coronary syndrome?
Cardiogenic shock
What is the treatment option selected in NSTEMI patients with a medium to high risk GRACE score?
Percutaneous coronary intervention will be performed within four days of admission
What is the treatment option selected in unstable NSTEMI?
Immediate coronary angiography with PCI
What lifestyle advice is used to prevent secondary acute coronary syndrome?
Stop smoking
Reduce alcohol consumption
Mediterranean diet
Cardiac rehabilitation
Optimise treatment of other conditions
What is cardiac rehabilitation?
It is a specific exercise regime for patients post MI
What are the six pharmacological management options used to prevent secondary acute coronary syndrome?
6As
Aspirin (75mg once daily)
Antiplatelet (clopidogrel, tricragrelor for 12 months)
Atorvastatin (80mg once daily)
ACEI (ramipril 10mg once daily)
Atenolol
Aldosterone antagonist (eplenerone 50mg once daily)
What are the five complications of MI?
DREAD
Death
Rupture of the heart septum/papillary muscle
eOedema (heart failure)
Arrhythmias/Aneurysms
Dressler’s syndrome
Which arrhythmia is associated with MI’s?
Ventricular fibrillation
How do we manage ventricular fibrillation, which has resulted in cardiac arrest?
We deliver DC shock 150V
In what two ways do we manage ventricular fibrillation, once spontaneous circulation has resumed?
Order ECG scan
Maintain saturations 94 - 96%
What is another term for Dressler’s syndrome?
Post myocardial infarction syndrome
When does Dressler’s syndrome occur?
2-3 weeks after an MI
What is Dressler’s syndrome?
It is caused by a localised immune response leading to pericarditis
What are the three clinical features of Dressler’s syndrome?
Pleuritic chest pain
Fever
Pericardial rub
What three investigations are used to diagnose Dressler’s syndrome?
Blood tests
ECG scan
ECHO
What blood tests are conducted to diagnose Dressler’s syndrome?
Inflammatory markers - such as CRP and ESR
What inflammatory marker blood result indicates Dressler’s syndrome?
Increased
What are the two features of Dressler’s syndrome on ECG?
Global ST elevation
T wave inversion
What is the features of Dressler’s syndrome on ECHO?
Pericardial effusion
What is the first line pharmacological management option for Dressler’s syndrome?
NSAIDs (aspirin/ibruprofen)
What is the second line pharmacological management option for Dressler’s syndrome?
Steroids (prednisolone)
What surgery is used to treat Dressler’s syndrome? What is the purpose of this procedure?
Pericardiocentesis
This is a procedure that removes fluid from around the heart
What is another complication of myocardial infarction?
Acute mitral regurgitation
How long after MIs does acute mitral regurgitation take to develop?
A few hours
What are the three clinical features of acute mitral regurgitation?
Flash pulmonary oedema
Breathlessness
Coarse bilateral lung crackles
What is flash pulmonary oedema?
It is when blood is directed back towards the pulmonary veins causing congestion in the lungs
What is a clinical feature of flash pulmonary oedema?
White frothy sputum production
What is another complication of myocardial infarction?
Ventricular septal defect
When does ventricular septal defect tend to present following myocardial infarction?
Within the first week
How does myocardial infarction lead to ventricular septal defects?
It can lead to ischaemic damage to the inter-ventricular septum
What are the two clinical features of ventricular septal defects?
Acute heart failure
Pan-systolic murmur
What investigation should be used to diagnose ventricular septal defects?
ECHO
