Acute coronary syndrome (Complete) Flashcards
What is acute coronary syndrome?
Umbrella term of acute presentations of ischaemic heart disease
What are the 3 subtypes of ACS?
STEMI
NSTEMI
Unstable angina
What are the main clinical features of ACS?
Chest pain
* Retrosternal
* ‘Crushing’/’pressure’
* Radiation to jaw/arms
Dyspnoea
Palpitations
Sweating
Nausea and vomitting
What are the main characteristics of ACS chest pain?
Central crushing chest pain
Radiation to jaw or arms
What types of patients present with atypical presentations of ACS?
Elderly
Diabetics
Females
What are atypical presentations of ACS?
Absence of chest pain and instead:
Epigastric pain
Syncope
Acute confusion
Acute breathlessness
Diabetic hyperglycaemic crises
What are the main investigations to consider in patients suspected of ACS?
Bedside:
Basic obs: Check for haemodynamic instability
ECG: Check for any changes suggestive of STEMI or NSTEMI
Bloods:
Troponin: Elevated in STEMI and NSTEMI
FBC: Check for anaemia/infection
CRP: Check for infection
Creatinine U&Es: Check for baseline kidney functions (needs to be good for PCI which uses contrast) and eGFR which is needed in GRACE score.
LFTs: Assess bleeding risk before anticoagulation
HbA1c: check for risk factor
Lipid profile: check for risk factors
Imaging:
CXR: Rule out other differentials of chest pain
What investigation findings are suggestive of unstable angina?
No troponin elevation
ECG findings:
* New ST deppresion
* New T-wave inversion (due to delays in repolarisation of inner layers of heart)
* No ECG changes
What investigation findings are suggestive of NSTEMI?
Elevated troponin
ECG changes:
* New ST-depression
* New T wave inversion
* Normal (1/3rd of patients)
What investigation findings are suggestive of STEMI?
Elevated troponin
ECG changes:
* New ST elevation
* New Left bundle branch block (LBBB)
What findings on ECG are suggestive of a posterior MI?
ST deppresion in the anterior and septal leads (V1-V4)
Peaked R waves in V1 and V2 (cell death posteriorly causes more positive depolarisation towards chest leads)
RCA or LCx commonly affected arteries in this case
What ECG findings must be present to diagnose a patient with STEMI?
Must show ST elevation in 2 or more continguous leads and:
ST elevation > 1mm in limb leads
ST elevation >2 mm in precordial leads (chest leads)
What findings must be shown to diagnose a patient with NSTEMI?
Patient must have signs/symptoms suggestive of ACS (N.B. Diabetics and elderly may be assymptomatic)
Elevated troponin
No ST elevation on ECG
ST elevation in which leads is suggestive of an inferior MI?
Which artery is affected?
Lead II
Lead III
Lead aVF
Artery affected: RCA
ST elevation in which leads is suggestive of an septal MI?
Which artery is affected?
V1
V2
Artery affected: Proximal LAD
ST elevation in which leads is suggestive of an anterior MI?
Which artery is affected?
V3-V4
Artery affected: LAD
ST elevation in which leads is suggestive of an MI in the apex?
Which artery is affected?
V5-V6
Potential arteries affected: Distal LAD, LCx, RCA
ST elevation in which leads is suggestive of an MI in the lateral aspect of the heart?
Which artery is affected?
Lead I
Lead aVL
Artery affected: Left circumflex (Lcx)
What is the common management for all types of ACS?
MONA:
Morphine
Oxygen (if sats below 94%)
Nitrates (IV or sublingual)
Aspirin (300mg)
Administration of nitrates in management of ACS should be considered with caution in which group of patients?
Hypotensive patients
What is the management plan for patients with STEMI?
When is percutaneous intervention indicated in patients with STEMI?
Within 12 hours of onset of symptoms
PCI can be done within 120 minutes of medical contact.
PCI can be considered if still showing signs of ongoing ischaemia after 12 hours
What mediation should be given before a PCI procedure in treatment of STEMI?
Dual antiplatelet therapy:
Aspirin
Prasugrel (or ticagrelor if bleeding risk)
What medication is given during a PCI procedure with radial access?
Unfractioned heparin
Glycoprotein inhibitor (GPI): for bailout
What medications are given during fibrinolysis (aka thrombolysis) of patient with STEMI?
Fibrinolytic drugs: Ateplase or tenecteplase
Parenteral anticoagulation: (e.g. Unfractioned heparin, fondaparinux, enoxaparin)
P12Y2 inhibitors: e.g.Ticagrelor (Clopidogrel if bleeding risk or on DOAC)
What medication should be swapped in patients in need of PCI who are already on antocoagulant?
Swap prasugrel for clopidogrel instead
(If patient is high bleeding risk but not on anticoagulant then swap for ticagrelor instead)
If patient still experiencing signs of ischaemia after fibrinolysis, what is next management for patient?
Percutaneous intervention
AKA Primary angioplasty
What is the management plan for patient with NSTEMI/Unstable angina?
What is the post MI management plan for patients?
Medicine:Should be started on 5 following drugs:
Aspirin 75mg (anti-platelet)
Clopidogrel 75mg or ticagrelor 90mg (second antiplatelet)
Beta-blocker (Bispropolol)
ACE-inhibitor
High dose statin (e.g. Atorvastatin 80mg)
Post MI investigations:
ECHO: All patients should have one done to check for any HF
Cardiac rehabilitation referral: All patients
Ischaemia testing: Consider for patients who havent have an angiography to check for inducible ischaemia.
What are some complications of MI?
Ventricular arrhythmia
2nd, 3rd degree heart block
Recurrent ischaemia/infarction/angina
Acute mitral regurgitation
Congestive heart failure
Cardiogenic shock
Cardiac tamponade
Ventricular septal defects
Left ventricular thrombus/aneurysm
Left/right ventricular free wall rupture
Dressler’s Syndrome
Acute pericarditis
How do ventricular arrythmias tend to present in patients with MI?
Tend to occur post MI, during cardiac catheterisation or during reperfusion.
Tend to be short-lived and self resolve
If they do persist however, they should be treated in accordance with advance life support protocols
How does recuurent ischaemia/infarction/angina tend to present in patients with MI?
Can re-occur due to thrombosing of inserted stents. (Requires re-intervention)
New infarcts can occur in new vascular territories
Angina and chest pain can last for a while after an MI, especially in patients with NSTEMI
Why are MI patients at risk of congestive heart failure?
Can occur as a consequence of impairment heart muscle function secondary to ischaemia.
Ventricular function may improve over months as heart muscle recovers
Hence why all patients require an ECHO
Heart block most commonly occcurs in which types of MI?
Inferior MI
This is because RCA supplies the SA node
How is heart block post-MI managed?
Observation as many resolve
Transcutaenous/venous pacing if symptomatic
Permament pacing if failure to resolve
How does left ventricular thrombus/aneurysm present?
Presents mainly in patients with anterior MI (this is because myocardium is suscpetible to stress and at risk of rupture)
May present silently, cause arrythymias or embolic events (e.g. stroke, acute limb ischaemia ect).
Persistent ST-elevation and signs of left ventricular failure
How is left ventricular aneurysm/thrombosis diagnosed?
ECHO
ECG may show persistent ST elevation
How does left ventricular wall rupture present and how is it managed?
Rapid tamponade as blood fills into pericardial space.
Tamponade followed by cardiac arrest/death within seconds
Managed by pericardiocentesis and surgery but prognosis extremely poor
Why can acute mitral regurgitation present in patients post MI?
Occurs because of papillary muscle rupture secondary to MI.
How does acute mitral regurgitation present in patients with MI?
Pansystolic murmur heard best at the apex
Severe and sudden heart failure
Diagnosed on ECHO and requires surgical intervention
What is ventricular septal defect?
Rupture in septum which seperates ventricles
How does ventricular septal defect tend to present in patients post MI?
Tends to present within first week post MI
Anterior MI tends to cause apical and simple ruptures
Inferior MI tends to cause basal and more complex ruptures
Presents with following symptoms:
Shortness of breath
Chest pain
Heart failure
Hypotension
Harsh, loud pan-systolic murmur along the left sternal border.
Palpable parasternal thrill.
How is ventricular septal defect post MI managed?
Emergency cardiac surgery
What is Dressler’s syndrome
Post-infaction pericarditis
When does Dressler’s syndrome typically present post MI?
2-3 week to a few months after MI (Patients that get pericarditis immediately after MI is NOT considered Dresslers syndrome)
N.B. Caused due to inflammatory response from ischaemic/necrotic tissue
How is Dressler’s syndrome managed?
High dose aspirin
What are contraindictions to fibrinloysis/thrombolysis?
Active internal bleeding
Recent haemorrhage, trauma or surgery (including dental extraction)
Coagulation and bleeding disorders
Intracranial neoplasm
Stroke < 3 months
Aortic dissection
Recent head injury
Severe hypertension
What biochemical marker is useful in identifying possible re-infarct of a patient who had a recent MI?
Creatinin kinase MB as it has quicker clearance than troponin
Most specific for myocardium and typically rasied 3 times above upper limit.
(Troponin wont be helpful as it can be raised up to 2 weeks post MI)
