EKG Flashcards
Regular P waves are positive in what leads and negative in what lead to be normal sinus?
I, II
AvR
The normal sinus atrial rate ranges from 40-180, what rates distinguish brady, tacky and normal?
<60 brady, 60-100 normal, 100-180 tachy
A sinus p wave is never negative in what leads?
AvF and II
What is the rate of ectopic supra ventricular tacky?
130-220
What is the atrial rate of flutter?
220-360
If atrial analysis cannot be determined, and there are narrow QRS waves, war are the 3 possibilities and their rates?
- VR < 140 → Sinus or A. flutter with 2:1 AV block
- VR > 180 → PVST
- VR 140-180 → any of the previous possibilities
If atrail analysis cannot be determined, and their are wide QRS, what should happen?
Go to ventricular analysis
In the atrioventricular analysis, what do we look at if the P:QRS ratio is 1:1?
PR interval length
- if greater than .2–> 1st degree AV block
In the atrioventricular analysis, what do we look at if the P:QRS ratio is not 1:1?
If AR>VR or vice versa
If AR>VR what types of blocks do we think about?
2nd and 3rd degree AV blocks
What type of block has PR intervals that vary?
How do we distinguish the difference?
Mobitz I and 3rd AV blocks
Does RR vary too?–if it does its Mobitz 1 or wenckebach
What type of block has AR>VR and the PR does not vary?
2nd degree mobitzII or 2:1 or advanced block
If AR<VR what is it?
Interference AV Dissasociation
When do we do a ventricular analysis?
Use when unable to find P waves or AV dissociation is present (3rd Degree AV block or interference)
What is the first think we look for in ventricular analysis?
is QRS >.12
If we have a wide QRS in ventricular dysrrhthymia , what are the 3 diagnosis and their rates?
< 40 → Ventricular escape rhythm
55-110 → Accelerated idioventricular rhythm
Often seen in the first few hours following a STEMI with Q waves
120-200+ → V. tach (monomorphic or Torsades) All regular and wide QRS tachycardias are V. tach until proven otherwise
If we are in the dysrrhthymia ventricular analysis and we have a normal QRS, what are the 3 diagnosis and their rates?
≤ 60 → Junctional escape rhythm
70-130 → Accelerated junctional escape rhythm
140-220 → PSVT
In ventricular analysis, we check the QRS first and then what next?
What are we looking for?
R-R intervals- unexpected QRS occurring early?
APCs or VPCs
What do we need to look at if their are unexpected long R-R intervals?
Whether or not a P wave is in the pause
If there is a long R-R and a p wave is in the pause in a premature fashion, what is the diagnosis? Ontime?
non-conducted APC
Mobitz I or II
If there is a long R-R and a p wave is absent in the pause, what is the diagnosis?
sinoatrial arrest
A normal QRS should be how big?
<.12
If the QRS is big and the PR is under .12, what should we immediately look for, and if we find it, what is the diagnosis?
Delta waves- WPW
DIAGNOSIS STOPS HERE
If QRS is big and the PR is normal, what are the 3 possible diagnosis?
RBBB, LBBB, and non-specific IVCD
If the QRS is big and the PR is normal. What do we see in RBBB?
RsR’ pattern or terminar R in the V1 or V2 leads
GO ON TO EVALUATE AXIS and Q waves
If the QRS is big and the PR is normal. What do we see in LBBB?
If there is mid-QRS notching or a deep negative Q or S wave V5 or V6
DIAGNOSIS STOPS HERE
AvL is at what degrees?
-30
lead I is at what degrees?
0
Lead AvR is at what degrees?
-150
LEAD II is at what degrees?
60
Lead III is at what degrees?
120
LEAD AvF is at what degrees?
90
What is the axis if lead I and II are positive?
-30 to 90= Normal
What is the axis if positive in I and negative in II?
-30 to -90= LAD
What is the axis if negative in I and positive in II?
90-180= RAD
What is exclusively from -45 to -90?
left anterior hemiblock
What can be the two possible diagnosis for an axis of -31 to -45?
Inferior MI or LVH
What 3 diagnosis do we need to think of if there is an RAD?
RVH (and or COPD), high lateral MI, left posterior hemlock
With RAD, what should we look for to diagnose RVH?
Huge R waves in V1
With RAD, what should we look for to diagnose high lateral MI?
weird Qs in lead I
What do we think if we don’t se large V1 R waves or Qs in lead I in RAD?
LPHB-(inferior MI signs might also be present and more confirmatory)
to evaluate QRS, what leads do we look for abnormal Qs in?
Leads I, II, aVF, and V2-V6
An abnormal Q is how big?
≥ 0.04 sec (≥ 1 small square in width), or 1/3 of the total QRS amplitude
Any q wave in what lead is always pathogenic regardless of the size?
V2
Abnormal Q waves in V2 or V3 suggest an infarct where?
anterior
Abnormal Q waves in V5 or V6 suggest an infarct where?
Lateral
Abnormal Q waves in V1 suggest an infarct where?
High lateral wall
Abnormal Q waves in AvF suggest an infarct where? What else should we look for?
Inferior
Relation of the QRS axis in the presence of definite inferior MI
- If the axis is -35 to -40 → LAD and inferior MI
- If the axis is -45 or beyond → LAHB and inferior MI
What should happen to R and S waves moving from V1 to V6?
R waves should become greater in magnitude while S waves become lesser in magnitude over the progression from Lead V1 to V6
If there are large R waves >5mm in V1 and normal QRS width, what 2 things should we think? how do we distinguish them?
True posterior infarct or RVH
- RAD?–>RVH
- path Q in AvF–>true posterior infarct (same artery to get an inferior infarct as posterior)
what is the Diagnosis If large R waves in Lead V5 or V6 and large Q or S waves in Lead V1 or V2
LVH needs to be >35mm
What is the last thing we need to check for in EKg?
T waves and ST abnormalities
If there are fairly localized ST elevations paired with ST depressions in the reciprocal leads, what does this suggest?
MI
If there are diffuse ST elevations in all leads except Leads V1 and aVL, what does this suggest? what lead may have a reciprocal ST depression?
Pericarditis
aVR
T_F–any ST depression is abnormal?
True
If ST depression is straight and oriented horizontally or down-sloping, is suggestive of what?
subendocardial ischemia, injury or infarction (NSTEMI)
What do we do after a 3rd degree AV block is determined?
QRS VENTRICULAR ANALYSIS
