Ischaemic Heart Disease Flashcards
ANTERIOR MI:
- Leads
- Vessels
- Heart part
- Complications
Anterior (V3- 4)
Anteroseptal (V1-4)
Anterolateral (V3-V6)
De Winter pattern
Wellens = impending
________
LAD
Anterior LV wall
IV septum
___________
CX:
- Death. ‘Widow maker’, most fatal
- LV failure/ cardiogenic shock
- Arrhythmia
INFERIOR MI:
- Leads
- Vessels
- Heart part
- Complications
II, III, aVF
Always look for RV extension!! (Apply right sided leads if suspected)
________
RCA\Circumflex
SA node, papillary mm
Inferior LV wall
_________
Bradycardia
AV block
Mitral incompetence
RV INFARCT risk
Posterior extension
LATERAL MI:
- Leads
- Vessels
- Heart part
- Complications
V5, V6
I, avL ‘high lateral’
__________
Circumflex
Lateral LV wall
L atrium
Uncommon in isolation
POSTERIOR MI:
- Leads
- Vessels
- Heart part
- Complications
Can occur in isolation, or as extension of inferior or lateral MI (extensive +, bad)
____________
Won’t see directly
Will see reciprocal STD in V1-V3
If this is seen, add on V7-9 for direct view
—> (only requires 0.5mm STE here!)
___________
Posterior Descending
Posterior LV wall
_________
If see anterior STD, always apply posterior leads
If see inferior or lateral STEMI, always check for evidence of posterior extension.
Wellen’s Syndrome:
Now resolved chest pain
+
Deeply inverted or biphasic, anterior T waves
…critical LAD occlusion.
__________
ECG may pseudonormalise when pain is present
Thought to be transient STEMI –> reperfusion, with risk of reocclusion at any moment.
De Winter pattern:
Tall, symmetrical T waves in praecordials
+
Upsloping ST depression
+
Reciprocal STE in aVR
…Active anterior MI (STEMI equivalent, without STE)
What are the STEMI equivalents?
ie. immediately activate cath lab:
1- De Winter’s
2- Posterior MI
3- Sgarbossa +
4- STE aVR
If:
- >1mm
- Diffuse ST depression
–> TVD, L main or proximal LAD
(Wellen’s is impending, not active MI)
(New LBBB no longer)
What ECG findings raise suspicion of an RV infarct?
Inferior STEMI- always look for RV signs:
STE III > II
STE V1 (or isoelectric) +\ ST depression V2
ECG features of ischaemia:
Q waves (old)
- >1mm wide, 2mm deep
- V1-3
Hyperacute T waves
- Broad, symmetrical
- >5mm (chest), >10mm (limb)
T wave flattening/ inversion or change
Poor R wave progression
Dynamicity
New LBBB
Modified Sgarbossa criteria
Use: LBBB, ventric pacing
- Concordant STE >1mm in >1 lead
- Concordant STD V1-3 >1mm in >1 lead
- Excessively discordant STE (>25% preceding S wave) in >1 lead
…90% sens/spec.
Late complications of MI:
LATE
- Dilated cardiomyopathy/ CCF
- Arrhythmia/ AV block
- Dressler’s
–> 1w to 3m
–> Usual Mx.
- LV aneurysm
–> 2 weeks +
- Mural thrombus
- VSD
- Rupture
–> Death
–> Pericardial effusion
STEMI definition/ when to call Code STEMI:
Typical symptoms >20mins
+
STE 1-2mm, >2 cont. leads, >20mins:
>2.5mm Ant. men <40
>2mm Ant. men >40
>1.5mm Ant. women
>1mm elsewhere
OR
Sgarbossa, STEMI equivalent (De Winter, STE aVR, anterior STD)
LV aneurysm:
2 weeks + after MI
On ECG, looks like anterior STEMI but:
- Nil reciprocal
- Q waves
- Not dynamic
+ clinical picture.
–> Rupture
–> Mural thrombus
–> Arrhythmia
Onset/duration of troponin and CK-MB:
Troponin
–> Onset 3-6 hours
–> Peaks 24 hours
–> Persists 2 WEEKS
CK-MB
Same
…… but gone after 2 DAYS
–> Better for assessing re-infarct
What is a ‘significant’ trop level:
> 99th centile (red)
Within range, but rise >20%
Recommended ‘timeframes’ for care in ACS (as per NHF):
ECG interpreted within 10 mins
_________
STEMI:
- Reperfuse if within 12 hours of onset
- Primary PCI if within 90mins of medical contact (otherwise lysis)
- Primary lysis best within 30mins ‘door to needle’
- After lysis, PCI within 24 hours
_________
NSTEAC: (eg. HEART)
- Very high risk: cath lab by 2 hours
- High risk: cath lab by 24 hours
- Intermediate risk: cath lab by72 hours
- Low risk: Non-invasive provocative strateg (to guide timing of cath)
_________
‘POSSIBLE’ ACS:
-
INITIAL management in NSTEACS:
- ECG seen within 10 mins
- O2 if sats <93%
- Aspirin 300mg
-
Second antiplatelet:
For PCI: Ticagrelor 180mg
For lysis: Clopidogrel 300mg -
Heparin
–> UFH 80units/kg
–> Clexane 1mg/kg SC daily -
GTN
–> Spray 400 x3, PO 400 x3, patch 25mg, infusion - Atorvastatin 80mg
- Morphine PRN
- Manage via validated pathway incl. risk strat
(HEART or ADAPT)
Management of cardiogenic shock (LV dysfunction) during STEMI:
- Optimise: oxygenation, pH, electrolytes, volume
- Norad in first instance
- Inotrope:- no best one
–> Dobutamine
–> Adrenaline (coronary perfusion)
—> Inodilator later - NIV as required for APO
- Urgent REPERFUSION!
- Overdrive pacing
- IABP
- ECMO
- Bypass
Management of RV infarct:
PRESERVE PRELOAD
Fluid bolus 10-20ml/kg
–> Unless overloaded
AVOID NITRATES
Avoid PPV if possible (intrathoracic pressures)
REDUCE RV AFTERLOAD- lungs
- Optimise oxygenation and acidosis
- Nitric
….Urgent REPERFUSION
Indications for thrombolysis in STEMI:
Within 12 hours of symptom onset
PCI not available within 90mins, or contraindicated
Contraindications for thrombolysis:
ABSOLUTE:
ICH ever
AVM or tumour
Stroke (within 3 months)
Dissection
Active bleeding (excluding menses)
GI or GU bleeding (4 weeks)
Trauma or surgery (3 weeks)
Non-compressible puncture (24hours)
RELATIVE:
BP >180/ 110
Anticoagulated
Isch stroke/ trauma/ surgery outside above windows
Pregnancy
Dose of thrombolytic in STEMI:
Alteplase 15mg then weight-based at 30 and 60mins
Reteplase 10mg IV. Repeat in 30mins
What defines ‘successful’ thrombolysis in STEMI:
50% STE resolution at 90mins
Resolved pain
(not stability- can be from infarcted tissue)
Disposition in NSTEACS by risk category:
Extremely high: 65% MACE
- Admit
- Telem
- PCI within 2 hours
High: 50% MACE
- Admit
- Telem
- PCI within 24 hours
Intermediate: 12-15% MACE
- Admit (no telem)
- PCI within 72 hours
OR
- DC
- PCI or non-invasive testing within 7 (max 14) days
Low: 1-2% MACE
- DC home
- Follow up with nil, GP, or chest pain clinic. Non-invasive +-
Features of unstable angina:
At lower levels of exertion
At rest
Persistent/ harder to relieve
Less responsive to GTN or rest
When should troponin be checked?
Different risk-strat pathways suggest different things. Local guidelines.
Initial:
- High/ very high-sens will detect from 3-6 hours
- Low-sens (POC) won’t detect for up to 12 hours
Delta:
2-3 hours
Single trop okay if:
- >12 hours resolved
- > 6 hours onset and high-sens normal
- >3 hours onset, high-sens AND undetectable “<3”
0 and 2 hour trop okay if:
- low risk ADAPT
0 and 3 hours okay if:
- Low risk HEART
ACCELERATED DIAGNOSTIC PROTOCOLS in possible ACS:
DC after single trop if:
- >12 hours (low sens)
- >6 hours (high sens)
- > 3 hours (high sens) AND undetectable (<3)
DC after 0 and TWO hour trops, if:
- ADAPT pathway low risk
DC after 0 and THREE hour trops, if:
- HEART score (pathway) low risk
__________
Any low sens trop needs at LEAST 12 hours
Any intermed/high HEART score should be admitted
Any intermed/high ADAPT score should continue ACS work up
ADAPT chest pain pathway:
Use on: ANY chest pain
Application: Decide who can have ACS ruled out after 2 hours.
Looks at: TIMI (patient factors) then adds on clinical factors (ECG + trop at 0 and 2 hrs)
Gives: 30 day MACE risk
ie. low risk ADAPT –> stop
Intermed/ high ADAPT –> standard ACS pathway
________
HEART score/ pathway
SUPERIOR to TIMI, GRACE.
6 week MACE risk.
Decide who can be discharged at 3 hours vs who needs consult/admission
________
0-3 = LOW 1-2% can be DC if 0 and 3hr trop okay
3-6= MOD 12- 16% -admit
6 or more = HIGH 50-60%- admit
TIMI (NSTEACS) score:
Inferior to HEART. THUMBS DOWN.
14 day MACE risk.
- Doesn’t consider symptoms of current pain episode
- Doesn’t weight any of the factors
- NOT used to assess safety of discharge
CHEST PAIN UNITS: Composition/ function
- Physically next to ED
- Monitoring beds
- Treatment/ diagnostics room
- ECG, biomarkers, CXR available within 30mins
- ACLS/defib available
- PCI available
–> At hospital
–> Predefined transfer plan - Admission criteria predefined by ED + Cardiology
- Risk stratification using validated tool (eg. HEART, ADAPT)
- Overseen by Cardiologist (direct, or in conjunction FACEM)
- Staffed with:
–> At least 1 doctor (can be registrar)
–> 1 nurse per 4 beds - Quality assurance program
Significance of STE in aVR:
If in the presence of widespread ST depression:
= Critical L main occlusion.
—> STEMI equivalent’
DDx:
- Prox LAD, TVD
- RBBB
- Any demand mismatch
Recognising MI in RBBB
NORMAL to have anterior (V1-V3) STD and/or TWI.
Unlike LBBB, can still see and interpret STE in RBBB- why Sgarbossa not used.
Additionally, even ISOELECTRIC ST segments anteriorly can be STE equivalent in RBBB (because STD is expected)
