Transcript Leads - VCOMcc

EKG’s
By: Robby Zehrung
Leads

In a 3-lead View there are two types of Leads:

Bipolar


Lead I: Right Arm to Left Arm

Lead II: Right Arm to Left Foot

Lead III: Left Arm to Left Foot
Unipolar

AVF: Left Foot to Heart

AVL: Left Arm to Heart

AVR: Right Arm to Heart
Deflection
Waves and Normal Values
Wave/Segment
P-Wave
PR-Interval
QRS Complex
ST Segment
QT-Segment
Length
Less than 0.12
0.12 to 0.20
0.04 to 0.12
N/A
Less than 0.44 sec
Height
Less than 2.5 mm
N/A
Variable
Isoelectric
N/A
Regularity and Rate


A rhythm can be Regular or Irregular

Regular- There is the same number of boxes between each R to R interval and the
same number of boxes between each P to P interval.

Irregular- The number of boxes between the R to R and P to P intervals varies.
To determine the rate you can use one of three methods:

Rule of 300- Count the number of Big boxes between the R to R interval and divide
it into 300)

Rule of 1500 (Count the number of small boxes between the R to R intervals and
divide it into 1500)

6 Second Rule- Count the number of boxes on a 6 second strip and multiple by 10.
(This is best when the regularity is irregular.)
Sinus Rhythms

Sinus Rhythm

Sinus Tachycardia

Sinus Bradycardia

Sinus Arrhythmia

Sinus Block

Sinus Arrest

Asystole
Sinus Rhythm
Systematic Approach
Regular
Rate
P-Wave
PR-Interval
QRS Complex
Characteristic of this Rhythm
Yes
60 to 100 BPM
Upright/Uniform/One for every QRS
0.12 to 0.20
Less than 0.12
Sinus Tachycardia
Systematic Approach
Regular
Rate
P-Wave
PR-Interval
QRS Complex
Characteristic of this Rhythm
Yes
100 to 150 BPM
Upright/Uniform/One for every QRS
0.12 to 0.20
Less than 0.12
Sinus Bradycardia
Systematic Approach
Regular
Rate
P-Wave
PR-Interval
QRS Complex
Characteristic of this Rhythm
Yes
Less than 60 BPM
Upright/Uniform/One for every QRS
0.12 to 0.20
Less than 0.12
Sinus Arrhythmia
Systematic Approach
Regular
Rate
P-Wave
PR-Interval
QRS Complex
Characteristic of this Rhythm
No
60 to 100 BPM
Upright/Uniform/One for every QRS
0.12 to 0.20
Less than 0.12
Sinus Block
Comes back in at regular interval!
Systematic Approach
Regular
Rate
P-Wave
PR-Interval
QRS Complex
Characteristic of this Rhythm
Regular
Depends on underlying Sinus Rhythm
Upright/Uniform/One for every QRS
0.12 to 0.20
Less than 0.12
Sinus Arrest
Comes back in at irregular interval!
Systematic Approach
Regular
Rate
P-Wave
PR-Interval
QRS Complex
Characteristic of this Rhythm
Regular
Depends on underlying Sinus Rhthm
Upright/Uniform/One for every QRS
0.12 to 0.20
Less than 0.12
Asystole
Systematic Approach
Regular
Rate
P-Wave
PR-Interval
QRS Complex
Characteristic of this Rhythm
N/A
0
N/A
N/A
N/A
Atrial Rythms

Atrial Fibrillation

Atrial Flutter

Supraventricular Tachycardia (PSVT or SVT)
Atrial Fibrillation
Systematic Approach
Regular
Rate
P-Wave
PR-Interval
QRS Complex
Characteristic of this Rhythm
No
Variable
Uncountable/multiple per QRS
N/A
Less than 0.12
Atrial Flutter
Systematic Approach
Regular
Rate
P-Wave
PR-Interval
QRS Complex
Characteristic of this Rhythm
P- Yes QRS-Variable
Variable
“Saw Tooth Pattern”
N/A
Less than 0.12
Supraventricular Tachycardia
PSVT or SVT
Systematic Approach
Regular
Rate
P-Wave
PR-Interval
QRS Complex
Characteristic of this Rhythm
Regular
Greater than 150
Buried in T-Wave
Unreadable
Less than 0.12
Junctional Rhythms

Junctional Rhythm

Accelerated Junctional Rhythm

Junctional Tachycardia
Junctional Rhythm
Systematic Approach
Regular
Rate
P-Wave
PR-Interval
QRS Complex
Characteristic of this Rhythm
Regular
40 to 60
Inverted/Absent/after QRS
If P-Wave Present less than 0.12
Less than 0.12
Accelerated Junctional Rhythm
Systematic Approach
Regular
Rate
P-Wave
PR-Interval
QRS Complex
Characteristic of this Rhythm
Regular
60 to 100
Inverted/Absent/after QRS
If P-Wave Present less than 0.12
Less than 0.12
Junctional Tachycardia
Systematic Approach
Regular
Rate
P-Wave
PR-Interval
QRS Complex
Characteristic of this Rhythm
Regular
Greater than 100
Inverted/Absent/after QRS
If P-Wave Present less than 0.12
Less than 0.12
AV Nodal Blocks

1st Degree Heart Block

2nd Degree Heart Block Type I

2nd Degree Heart Block Type II

3rd Degree Heart Block
1st Degree Block
Systematic Approach
Regular
Rate
P-Wave
PR-Interval
QRS Complex
Characteristic of this Rhythm
Regular
Depends on Underlying Rhythm (usually 60
to 100 BPM)
Uniform/Upright/One for every QRS
Greater than 0.20/Constant
Less than 0.12
2nd Degree Type I
Systematic Approach
Regular
Rate
P-Wave
PR-Interval
QRS Complex
Characteristic of this Rhythm
Regular w/Occasional Dropped QRS
Depends on Underlying Rhythm (usually 60
to 100 BPM)
Uniform/Upright/One for every QRS
Gradual Lengthening with each beat
Less than 0.12 (Occasional Dropped QRS)
2nd Degree Type II
Systematic Approach
Regular
Rate
P-Wave
PR-Interval
QRS Complex
Characteristic of this Rhythm
Regular w/Occasional Dropped QRS
Depends on Underlying Rhythm (usually 60
to 100 BPM)
Uniform/Upright/One for every QRS
0.12 to 0.2 w/Consistent with each beat
Less than 0.12 (Occasional Dropped QRS)
3rd Degree Block
Systematic Approach
Regular
Rate
P-Wave
PR-Interval
QRS Complex
Characteristic of this Rhythm
Regular P Waves/Regular QRS
Depends on Underlying Rhythm (usually 60
to 100 BPM)
Uniform/Upright/Out of Sync with QRS
Unmeasurable
Wider than 0.12
Ventricular Rhythms

Ventricular Tachycardia

Ventricular Fibrillation

Torsades De Pointes
Ventricular Tachycardia
Systematic Approach
Regular
Rate
P-Wave
PR-Interval
QRS Complex
Characteristic of this Rhythm
Regular QRS
Greater than 150
None
None
Wider than 0.12
Ventricular Fibrillation
Systematic Approach
Regular
Rate
P-Wave
PR-Interval
QRS Complex
Characteristic of this Rhythm
Irregular QRS
Unmeasurable
None
None
Unmesurable
Torsades De Pointes
Systematic Approach
Regular
Rate
P-Wave
PR-Interval
QRS Complex
Characteristic of this Rhythm
Irregular QRS
Greater than 150
None
None
Greater than 0.12
Random Escape Rhythms

PAC

PJC

PVC

Unifocal

Multifocal

Couplets

Bigeminal PVC
Premature Atrial Contraction
Systematic Approach
Regular
Rate
P-Wave
PR-Interval
QRS Complex
Characteristic of this Rhythm
Regular depending on underlying rhythm
Depends on underlying rhythm
Upright/uniform/one for every QRS
0.12 to 0.20
0.04 to 0.12
Premature Junctional Contraction
Systematic Approach
Regular
Rate
P-Wave
PR-Interval
QRS Complex
Characteristic of this Rhythm
Regular depending on underlying rhythm
Depends on underlying rhythm
Upright/uniform/one for every QRS
0.12 to 0.20
0.04 to 0.12
Premature Ventricular Contraction:
Unifocal
Systematic Approach
Characteristic of this Rhythm
Regular
Regular depending on underlying rhythm
Rate
Depends on underlying rhythm
P-Wave
Upright/uniform/one for every QRS
PR-Interval
0.12 to 0.20
QRS Complex
0.04 to 0.12
Premature Ventricular Contraction:
Multifocal
Systematic Approach
Characteristic of this Rhythm
Regular
Regular depending on underlying rhythm
Rate
Depends on underlying rhythm
P-Wave
Upright/uniform/one for every QRS
PR-Interval
0.12 to 0.20
QRS Complex
0.04 to 0.12
Premature Ventricular Contraction:
Couplets
Systematic Approach
Characteristic of this Rhythm
Regular
Regular depending on underlying rhythm
Rate
Depends on underlying rhythm
P-Wave
Upright/uniform/one for every QRS
PR-Interval
0.12 to 0.20
QRS Complex
0.04 to 0.12
Premature Ventricular Contraction:
Bigeminal
Systematic Approach
Characteristic of this Rhythm
Regular
Regular depending on underlying rhythm
Rate
Depends on underlying rhythm
P-Wave
Upright/uniform/one for every QRS
PR-Interval
0.12 to 0.20
QRS Complex
0.04 to 0.12
12-Leads

Chest Leads

Hypertrophy and Enlargement

Axis Deviation

Bundle Branch Block

Ischemia

Q-Wave

ST-Segment Elevation

Posterior MI
Unipolar Chest Leads

V1 though V6
Ventricular Hypertrophy

Left Ventricular
Hypertrophy


Greatest R Wave in Leads
V5 or V6 added to the
Deepest S-Wave in either
V1 or V2
If Greater than 35 mm =
positive for LVH
R in Lead I and S in Lead
III is greater than 25 mm =
LVH
OR

Right Ventricular
Hypertrophy

In V1

R to S ratio greater than
1
And

Inverted T-Wave
Or
OR



R Greater than 6 mm

S less than 2 mm
Or

R in Leads aVR Greater
than 12 mm = LVH
rSR’ with R greater than
10 mm
Atrial Enlargement

Left Atrial Enlargement

Lead II greater than
0.04 sec between two
notched peaks on a pwave
OR


Right Atrial
Enlargement

Lead II P-wave
greater than 2.5 mm
tall
OR
V1 negative
deflection greater of
biphasic P-Wave
greater than 1 little
box wide and 1 little
box deep

Lead V1 or V2 P wave
greater than 1.5 mm
tall
Axis Deviation

Axis Deviation is the net direction
that the electrical activity of the
heart is flowing and is measured in
degrees.

Normal Axis: 0 to 90 degrees

Right Axis: 90 to 180 degrees

Left Axis: Physiologic 0 to -40

Left Axis: Pathologic -40 to -90

Extreme Right Axis Deviation: -90
to -180
Axis Deviation

Equiphasic Approach

Quadrant Approach
Equiphasic Approach

Rules

Step 1: Fine the most Equiphasic QRS in
LEAds I, II, III, aVF, aVR, or aVL

Step 2: Look at Hexaxial wheel and find
the lead that corresponds with step one.

Step 3: Fine the lead 90 degrees to the
lead identified in step two.

Step 4: Identify the lead from step three
on the 12-lead and determine if it is
upright or negative.

Step 5: If upright, find it on the hexaxial
wheel and it’s degree is the axis
deviation.
Or

Step 5: If negative find it on the hexaxial
wheel and it’s degree minus 180 degrees
is the axis deviation.
Equiphasic Approach

Step 1: Find the
most Equiphasic
QRS complex in
LEAds I, II, III, aVF,
aVR, or aVL

For this 12-Lead it
is aVR
Equiphasic Approach

Step 2: Look at Hexaxial wheel
and find the lead that
corresponds with step one.

aVR was the lead and if you
look at the hexaxial wheel it’s
aVR is at -150 degrees
Equiphasic Approach

Step 3: Find the lead 90 degrees to the lead
identified in step two.

In this case the lead that is 90 degrees to aVR on
the Hexaxial Reference System is Lead III.

Lead III is noted to be at 120 degrees.
Equiphasic Approach

Step 4: Identify
the lead from
step three on
the 12-lead and
determine if it is
upright or
negative.

Lead III is noted
to be
predominantly
positive
Equiphasic Approach

Step 5:

If upright, find it on the hexaxial wheel and it’s degree is the axis deviation.
OR

If negative find it on the hexaxial wheel and it’s degree minus 180 degrees is the axis
deviation.

Lead III was upright so the axis deviation for this 12-lead EKG would be 120
degrees.

If lead III was negative the axis deviation for this 12-lead EKG would be 120
degrees minus 180 which equals -60.
Quadrant Approach

Determine
deflection in Lead I
and aVF

Upright I/ Upright
aVF = Normal Axis
Deviation

Upright I/Negative
aVF = Left Axis
Devation

Negative I /
Upright aVF = Right
Axis Deviation

Negative I /
Negative aVF =
Extreme Right Axis
Deviation or “No
Mans Land”
Quadrant Approach: left axis deviation

If axis deviation is determined to be LAD do the following:

Look at lead II

If positive or equiphasic then it is physiologic Left Axis Deviation
OR

If negative then it is pathologic Left Axis Deviation
Bundle Branch Block

LBBB

RBBB
Left Bundle Branch Block

Rules

QRS is greater than
0.12

Look at V1 and
determine if the
terminal portion of
the QRS is positive or
negative

If negative = LBBB
Right Bundle Branch Block

Rules

QRS greater than 0.12

Look at V1 and
determine if the
terminal portion of the
QRS is positive or
negative

If Positive= RBBB
“Contiguous Leads”

I (Inferior)

See (Septal)

All (Anterior)

Leads (Lateral)
Inferior (II, III, aVF)
Septal (V1,V2)
Anterior (V3,V4)
Lateral (V5, V6, Lead I, and aVL)
Q-Wave Importance

If a significant QWave is present this
indicates prior injury
to the heart
Myocardial Ischemia

ST Segment
Depression of 1 mm
or more in
contiguous leads =
Ischemia to the
heart

Here II, III, aVF, and
V3 through V6 shows
ST Segment
Depression.

So this would be
InferoSeptoLateral
ischemia.
Myocardial Infarction

ST- Segment
Elevation of 1 mm
in two contiguous
leads.
Anterior MI
Lateral MI
Inferior MI

Commonly has
Right sided
involvement
Septal MI
Posterior MI

Suspect Posterior MI if
you have an Inferior

Look at Leads V1/V2

No ST Segment
Elevation is Present

V1/V2 have significant
ST Depression

Flip the Paper upside
down

After flipping the
paper upside down, if
Elevation is present in
V1 and V2 w/q-wave
this is likely a Posterior
MI