ECG Flashcards
Territory distribution on ECG
Inferior: II, III, AVF
Anterior: V1-V4
(septal V1-V2)
Lateral: V5-6, I, AVL
What supplies the SA node?
RCA 90%
LCX 10%
Criteria for emergency revasculation
ST elevation in 2 contiguous leads after NTG
Typical symptoms up to 12 hours
Persistent symptoms to 24 hours
New LBBB with typical symptoms (not really used anymore)
ST segment elevation criteria?
>1 mm above baseline (limb) >2 mm above baseline (chest) 0.08 seconds to right of J point compare to baseline of TP segment Look for 2 contiguous leads
What are ECG findings in RV infarct?
STE III>II
STE in V1
STE in V4R
5 findings of Posterior MI on 12 lead ECG?
Leads V1-V3: ST depression Prominent R wave R>S in V2 Prominent upright T wave Co-existing acute inferior and/or lateral MI
DDx of tall R wave in V1
RBBB Posterior MI RVH RV strain Pediatric WPW Muscular dystrophy
What criteria define pathologic Q waves?
Duration >40 ms (1 small box)
>25% of QRS complex amplitude
2 contiguous leads
age indeterminate MI
What are criteria for low voltage ECG?
< 5 mm QRS complex in all limb leads
ECG findings of left main occlusion?
Widespread ST depression (inferior, anterior, lateral)
STE in AVR >/= 1 mm
STE in V1 >/= 1 mm
What is the DDx of left axis deviation?
LVH
LAFB
Inferior ischemia/Q waves
What are Sgarbossa’s Criteria?
high specificity, low sensitivity
Concordant ST elevation of 1 mm = 5 mm
Concordant ST depression of 1 mm V1-V3 = 3 points
Excessive discordant ST segment elevation of >5 mm = 2 points
Score >/=3 has 90% specificity for diagnosing MI
DDx of inverted T waves (6)
Ischemia RV strain (PE, COPD, pulm HTN) Persistent juvenile T waves Intracranial pathology Hyperventilation Electrolytes (K)
4 causes of acute RBBB that can kill you
Ischemia
PE
TCA/Na channel blockade
Hyperkalemia
DDx ST elevation (10)
STEMI vasospasm aortic dissection BER Pericarditis takotsubo LBBB RBBB LV aneurysm Brugada Osborne wave Epsilon wave Post cardioversion PE
Ddx of Wide QRS
Acidosis
HyperK
Sodium channel blockade
BBB
Ddx of long QT
Congenital Metabolic - hypoK, hypoMg, hypoCa Medications Antiarrhythmics, anti emetics, antibiotics, analgesics, antipsychotics Chemotherapy agents Ischemia Post cardiac arrest Hypothermia
DDx of irregularly irregular rhythm?
Atrial fibrillation
Atrial flutter with variable conduction
Multi focal atrial tachycardia
(>/= 3 P wave morphological with distinct PR intervals and HR >100)
A fib with slow ventricular response? DDx
Digoxin toxicity Beta blocker toxicity CCB toxicity Adenosine toxicity Amiodarone toxicity AV nodal conduction disease Ischemia Hyperkemia
Where is the source of a complex that is R>R1?
Ventricle
What vessel perfumes the AV node?
RCA in 90%
DDx of R>S in V1-2
Posterior MI RBBB Pediatric Lead reversal RVH VTach WPW
What is the initial setting of a transvenous pacer? After placement?
- V00 - low sensitivity
2. VVI - senses beats
