2011-06-17_belajar ekg (dr.ika spjp)
TRANSCRIPT
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
1/129
ECG RHYTHM INTERPRETATIONECG Basics
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
2/129
Reading 12-Lead ECGs
The best way to read 12-lead ECGs is to develop a step-by-stepapproach (just as we did for analyzing a rhythm strip). In thesemodules we present a 6-step approach:
1. Determine RHYTHM2. Calculate RATE3. Determine QRS AXIS
4. Calculate INTERVALS5. Assess for HYPERTROPHY6. Look for evidence of INFARCTION
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
3/129
Rhythm Rate Axis Intervals HypertrophyInfarct
how to systematically analyze a rhythm bylooking at the rate , regularity, P waves, PR
interval and QRS complexes.
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
4/129
Rhythm Analysis
Step 1: Determine regularity.Step 2: Calculate rateStep 3: Assess the P waves.
Step 4: Determine PR interval.Step 5: Determine QRS duration.
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
5/129
Rhythm Rate Axis Intervals HypertrophyInfarct
Tip: the rhythm strip portion of the 12-lead ECG is a goodplace to look at when trying to determine the rhythm becausethe 12 leads only capture a few beats.
Lead II
Rhythm?
Atrial fibrillation
Rhythm strip
1 of 12 leads
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
6/129
Determine regularity
Look at the R-R distances (using a caliper ormarkings on a pen or paper).Regular (are they equidistant apart)?Occasionally irregular? Regularly irregular?Irregularly irregular?
Interpretation? Regular
R R
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
7/129
Assess the P waves
Are there P waves?Do the P waves all look alike?Do the P waves occur at a regular rate?Is there one P wave before each QRS?
Interpretation? Normal P waves with 1 P wave for every QRS
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
8/129
Arrhythmia Formation
Arrhythmias can arise from problems in the: Sinus node Atrial cells AV junction
Ventricular cells
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
9/129
SA Node Problems
The SA Node can:fire too slow
fire too fast
Sinus Bradycardia
Sinus Tachycardia
Sinus Tachycardia may be an appropriateresponse to stress.
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
10/129
Atrial Cell Problems
Atrial cells can:fire occasionally
from a focus
fire continuously
due to a looping re-entrant circuit
Premature Atrial
Contractions (PACs)
Atrial Flutter
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
11/129
Teaching Moment
A re-entrantpathway occurswhen an impulseloops and results inself-perpetuating
impulse formation.
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
12/129
Atrial Cell Problems
Atrial cells can also: fire continuously
from multiple fociorfire continuously
due to multiplemicro re-entrantwavelets
Atrial Fibrillation
Atrial Fibrillation
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
13/129
Teaching Moment
Multiple micro re-entrant waveletsrefers to wanderingsmall areas ofactivation whichgenerate fine chaoticimpulses. Collidingwavelets can, in turn,generate new foci ofactivation.
Atrial tissue
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
14/129
AV Junctional Problems
The AV junction can:fire continuouslydue to a looping re-entrant circuitblock impulsescoming from the SANode
Paroxysmal Supraventricular Tachycardia
AV Junctional Blocks
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
15/129
Ventricular Cell Problems
Ventricular cells can:fire occasionallyfrom 1 or more focifire continuouslyfrom multiple foci
fire continuouslydue to a looping re-entrant circuit
Premature Ventricular Contractions (PVCs)
Ventricular Fibrillation
Ventricular Tachycardia
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
16/129
Arrhythmias
Sinus Rhythms Premature Beats Supraventricular ArrhythmiasVentricular Arrhythmias
AV Junctional Blocks
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
17/129
Sinus Rhythms
Sinus Bradycardia
Sinus Tachycardia
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
18/129
Rhythm #1
30 bpm Rate? Regularity? regular normal
0.10 s
P waves?
PR interval? 0.12 s QRS duration?
Interpretation? Sinus Bradycardia
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
19/129
Sinus Bradycardia
Deviation from NSR
- Rate < 60 bpm
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
20/129
Sinus Bradycardia
Etiology: SA node is depolarizing slower than
normal, impulse is conducted normally (i.e.normal PR and QRS interval).
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
21/129
Rhythm #2
130 bpm Rate? Regularity? regular normal
0.08 s
P waves?
PR interval? 0.16 s QRS duration?
Interpretation? Sinus Tachycardia
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
22/129
Sinus Tachycardia
Deviation from NSR
- Rate > 100 bpm
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
23/129
Sinus Tachycardia
Etiology: SA node is depolarizing faster thannormal, impulse is conducted normally.Remember: sinus tachycardia is a response tophysical or psychological stress, not a primary
arrhythmia.
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
24/129
Premature Beats
Premature Atrial Contractions (PACs)
Premature Ventricular Contractions (PVCs)
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
25/129
Rhythm #3
70 bpm Rate? Regularity? occasionally irreg. 2/7 different contour
0.08 s
P waves?
PR interval? 0.14 s (except 2/7) QRS duration?
Interpretation? NSR with Premature Atrial
Contractions
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
26/129
Premature AtrialContractions
Deviation from NSRThese ectopic beats originate in the atria(but not in the SA node), therefore thecontour of the P wave, the PR interval,and the timing are different than anormally generated pulse from the SAnode.
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
27/129
Premature Atrial
Contractions
Etiology: Excitation of an atrial cell forms animpulse that is then conducted normallythrough the AV node and ventricles.
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
28/129
Teaching Moment
When an impulse originates anywhere in theatria (SA node, atrial cells, AV node, Bundle of
His) and then is conducted normally throughthe ventricles, the QRS will be narrow (0.04 -0.12 s).
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
29/129
Rhythm #4
60 bpm
Rate? Regularity? occasionally irreg.
none for 7 th QRS
0.08 s (7th wide)
P waves?
PR interval? 0.14 s QRS duration?
Interpretation? Sinus Rhythm with 1 PVC
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
30/129
PVCs
Deviation from NSR Ectopic beats originate in the ventricles resulting inwide and bizarre QRS complexes.When there are more than 1 premature beats andlook alike, they are called uniform. When theylook different, they are called multiform.
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
31/129
PVCs
Etiology: One or more ventricular cells aredepolarizing and the impulses are abnormallyconducting through the ventricles.
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
32/129
Teaching Moment
When an impulse originates in a ventricle,conduction through the ventricles will beinefficient and the QRS will be wide andbizarre.
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
33/129
Ventricular Conduction
Normal Signal moves rapidlythrough the ventricles
Abnormal Signal moves slowlythrough the ventricles
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
34/129
Arrhythmias
Sinus RhythmsPremature Beats
Supraventricular ArrhythmiasVentricular Arrhythmias
AV Junctional Blocks
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
35/129
Supraventricular Arrhythmias
Atrial Fibrillation
Atrial Flutter
Paroxysmal Supraventricular Tachycardia
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
36/129
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
37/129
Atrial Fibrillation
Deviation from NSR No organized atrial depolarization, so nonormal P waves (impulses are notoriginating from the sinus node).Atrial activity is chaotic (resulting in an
irregularly irregular rate).Common, affects 2-4%, up to 5-10% if > 80years old
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
38/129
Atrial Fibrillation
Etiology: Recent theories suggest that it isdue to multiple re-entrant waveletsconducted between the R & L atria. Eitherway, impulses are formed in a totallyunpredictable fashion. The AV node allows
some of the impulses to pass through atvariable intervals (so rhythm is irregularlyirregular).
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
39/129
Rhythm #6
70 bpm Rate? Regularity? regular
flutter waves
0.06 s
P waves?
PR interval? none QRS duration?
Interpretation? Atrial Flutter
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
40/129
Atrial Flutter
Deviation from NSRNo P waves. Instead flutter waves (notesawtooth pattern) are formed at a rateof 250 - 350 bpm.
Only some impulses conduct through theAV node (usually every other impulse).
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
41/129
Atrial Flutter
Etiology: Reentrant pathway in the rightatrium with every 2nd, 3rd or 4th impulsegenerating a QRS (others are blocked in theAV node as the node repolarizes).
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
42/129
Rhythm #7
74 148 bpm Rate? Regularity? Regular regular
Normal none
0.08 s
P waves?
PR interval? 0.16 s none QRS duration?
Interpretation? Paroxysmal Supraventricular
Tachycardia (PSVT)
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
43/129
PSVT
Deviation from NSRThe heart rate suddenly speeds up, oftentriggered by a PAC (not seen here) and theP waves are lost.
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
44/129
PSVT
Etiology: There are several types of PSVT butall originate above the ventricles (therefore theQRS is narrow).
Most common: abnormal conduction in the AVnode (reentrant circuit looping in the AV node).
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
45/129
Ventricular Arrhythmias
Ventricular Tachycardia
Ventricular Fibrillation
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
46/129
Rhythm #8
160 bpm Rate? Regularity? regular
none
wide (> 0.12 sec)
P waves?
PR interval? none QRS duration?
Interpretation? Ventricular Tachycardia
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
47/129
Ventricular Tachycardia
Deviation from NSR Impulse is originating in the ventricles (noP waves, wide QRS).
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
48/129
Ventricular Tachycardia
Etiology: There is a re-entrant pathwaylooping in a ventricle (most common cause).
Ventricular tachycardia can sometimes
generate enough cardiac output to produce apulse; at other times no pulse can be felt.
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
49/129
Rhythm #9
none Rate? Regularity? irregularly irreg.
none
wide, if recognizable
P waves?
PR interval? none QRS duration?
Interpretation? Ventricular Fibrillation
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
50/129
Ventricular Fibrillation
Deviation from NSR Completely abnormal.
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
51/129
Ventricular Fibrillation
Etiology: The ventricular cells are excitableand depolarizing randomly.
Rapid drop in cardiac output and deathoccurs if not quickly reversed
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
52/129
Arrhythmias
Sinus RhythmsPremature Beats
Supraventricular ArrhythmiasVentricular ArrhythmiasAV Junctional Blocks
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
53/129
AV Nodal Blocks
1st Degree AV Block
2nd Degree AV Block, Type I
2nd Degree AV Block, Type II
3rd Degree AV Block
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
54/129
Rhythm #10
60 bpm Rate? Regularity? regular
normal
0.08 s
P waves?
PR interval? 0.36 s QRS duration?
Interpretation? 1st Degree AV Block
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
55/129
1st Degree AV Block
Deviation from NSR PR Interval > 0.20 s
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
56/129
1st Degree AV Block
Etiology: Prolonged conduction delay in theAV node or Bundle of His.
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
57/129
Rhythm #11
50 bpm Rate? Regularity? regularly irregular
nl, but 4th no QRS
0.08 s
P waves?
PR interval? lengthens QRS duration?
Interpretation? 2nd Degree AV Block, Type I
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
58/129
2nd Degree AV Block, Type I
Deviation from NSRPR interval progressively lengthens, thenthe impulse is completely blocked (P wavenot followed by QRS).
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
59/129
2nd Degree AV Block, Type I
Etiology: Each successive atrial impulseencounters a longer and longer delay in theAV node until one impulse (usually the 3rd or4th) fails to make it through the AV node.
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
60/129
Rhythm #12
40 bpm Rate? Regularity? regular
nl, 2 of 3 no QRS
0.08 s
P waves?
PR interval? 0.14 s QRS duration?
Interpretation? 2nd Degree AV Block, Type II
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
61/129
2nd Degree AV Block, Type II
Deviation from NSR Occasional P waves are completelyblocked (P wave not followed by QRS).
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
62/129
2nd Degree AV Block, Type II
Etiology: Conduction is all or nothing (noprolongation of PR interval); typically blockoccurs in the Bundle of His.
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
63/129
Rhythm #13
40 bpm Rate? Regularity? regular
no relation to QRS
wide (> 0.12 s)
P waves?
PR interval? none QRS duration?
Interpretation? 3rd Degree AV Block
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
64/129
3rd Degree AV Block
Deviation from NSR The P waves are completely blocked in theAV junction; QRS complexes originateindependently from below the junction.
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
65/129
3rd Degree AV Block
Etiology: There is complete block of conduction in the AV junction, so the atriaand ventricles form impulses independentlyof each other. Without impulses from the
atria, the ventricles own intrinsic pacemakerkicks in at around 30 - 45 beats/minute.
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
66/129
Remember
When an impulse originates in a ventricle,conduction through the ventricles will beinefficient and the QRS will be wide and bizarre.
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
67/129
Rhythm Rate Axis Intervals HypertrophyInfarct
If you use the rhythmstrip portion of the 12-lead ECG the total
length of it is always 10seconds long. So youcan count the numberof R waves in therhythm strip and
multiply by 6 todetermine the beatsper minute. Rate? 12 (R waves) x 6 = 72 bpm
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
68/129
Calculate Rate
Option 1Count the # of R waves in a 6 second rhythm strip,then multiply by 10.Reminder: all rhythm strips in the Modules are 6
seconds in length.Interpretation?
9 x 10 = 90 bpm
3 sec 3 sec
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
69/129
Calculate Rate
Option 2Find a R wave that lands on a bold line.Count the # of large boxes to the next R wave. If the second R wave is 1 large box away the rate is300, 2 boxes - 150, 3 boxes - 100, 4 boxes - 75, etc.(cont)
R wave
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
70/129
Calculate Rate
Option 2 (cont)1500 : ( small boxes R-R )300 : ( medium boxes R-R )
Interpretation?
3
00
1
50
1
00 75 60 50
1500 : 15 = 100 300 : 3 = 100
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
71/129
Normal Sinus Rhythm (NSR)
Etiology: the electrical impulse is formed inthe SA node and conducted normally.
This is the normal rhythm of the heart; otherrhythms that do not conduct via the typical
pathway are called arrhythmias.
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
72/129
NSR Parameters
Rate 60 - 100 bpm Regularity regular P waves normal PR interval 0.12 - 0.20 s QRS duration 0.04 - 0.12 s
Any deviation from above is sinus tachycardia,sinus bradycardia or an arrhythmia
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
73/129
Rhythm Rate Axis Intervals HypertrophyInfarct
Axisrefers to the mean QRS axis (or vector) during ventriculardepolarization. As you recall when the ventricles depolarize (in a normalheart) the direction of current flows leftward and downward because mostof the ventricular mass is in the left ventricle. We like to know the QRS axis
because an abnormal axis can suggest disease such as pulmonaryhypertension from a pulmonary embolism.
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
74/129
Rhythm Rate Axis Intervals HypertrophyInfarct
The QRS axis is determined by overlying a circle, in the frontal plane.By convention, the degrees of the circle are as shown.
The normal QRS axis lies between -30 o and +90 o.
0o
30 o
-30 o
60 o
-60 o-90 o
-120 o
90 o 120o
150 o
180 o
-150 o
A QRS axis that falls between -30 o and -90 o is abnormal and called leftaxis deviation.
A QRS axis that falls between +90 o and +150 o is abnormal and calledright axis deviation .
A QRS axis that falls between +150 o and -90 o is abnormal and calledsuperior right axis deviation .
A i
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
75/129
Rhythm Rate Axis Intervals HypertrophyInfarct
We can quickly determine whether the QRS axis is normal bylooking at leads I and II.
If the QRS complex isoverall positive (R > Q+S) in leads I and II, the QRSaxis is normal .
QRS negative (R < Q+S)
In this ECG what leadshave QRS complexesthat are negative?equivocal?
QRS equivocal (R = Q+S)
A i
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
76/129
0o
30 o
-30 o
60 o
-60 o-90 o
-120 o
90 o 120o
150 o
180 o
-150 o
Rhythm Rate Axis Intervals HypertrophyInfarct
if the QRS is negative in lead I and negative in lead II what is the QRS axis?(normal, left, right or right superior axis deviation)
QRS Complexes
I
AxisI II+ ++ -
- +
- -
normalleft axis deviationright axis deviation
right superioraxis deviation
0o
30 o
-30 o
60 o
-60 o-90 o
-120 o
90 o 120o
150 o
180 o
-150 o
II
A i
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
77/129
Rate Rhythm Axis Intervals HypertrophyInfarct
Is the QRS axis normal in this ECG? No, there is left axis deviation.
The QRS is positive in I and negative in II.
A i
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
78/129
Rhythm Rate Axis Intervals HypertrophyInfarct
To summarize:The normal QRS axis falls between -30 o and +90 o because ventriculardepolarization is leftward and downward.Left axis deviation occurs when the axis falls between -30 o and -90 o.Right axis deviation occurs when the axis falls between +90 o and +150o.Right superior axis deviation occurs when the axis falls between between +150 o and -90 o.
QRS Complexes
AxisI II
+ ++ -
- +
- -
normalleft axis deviationright axis deviation
right superioraxis deviation
A quick way to determinethe QRS axis is to look at theQRS complexes in leads Iand II.
I l
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
79/129
PR interval
< 0.12 s 0.12-0.20 s > 0.20 s
High catecholaminestates
Wolff-Parkinson-WhiteNormal AV nodal blocks
Wolff-Parkinson-White 1st Degree AV Block
Rhythm Rate Axis Intervals HypertrophyInfarct
I t l
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
80/129
QRS complex
< 0.10 s 0.10-0.12 s > 0.12 s
Normal Incomplete bundlebranch block
Bundle branch blockPVC
Ventricular rhythm
Remember: If you have a BBB determine if it is a right or left BBB. If you need a refresher see Module VI .
3 rd degree AV block withventricular escape rhythm
Incomplete bundle branch block
Rhythm Rate Axis Intervals HypertrophyInfarct
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
81/129
QT interval
The duration of the QT interval isproportionate to the heart rate. The fasterthe heart beats, the faster the ventriclesrepolarize so the shorter the QT interval.Therefore what is a normal QT varieswith the heart rate. For each heart rate youneed to calculate an adjusted QT interval,called the corrected QT (QTc):
QTc = QT / square root of RR interval
Rhythm Rate Axis Intervals HypertrophyInfarct
I t l
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
82/129
Rate Rhythm Axis Intervals HypertrophyInfarct
QTc interval
< 0.44 s > 0.44 s
Normal Long QT
A prolonged QT can be very dangerous. It may predispose an individual to a type of ventricular tachycardia called Torsades de Pointes. Causes include drugs, electrolyte abnormalities, CNS disease, post-MI, and congenital heart disease.
Torsades de Pointes
Long QT
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
83/129
Rate Rhythm Axis Intervals HypertrophyInfarct
PR interval? QRS width? QTc interval?0.08 seconds 0.16 seconds 0.49 seconds
QT = 0.40 s
RR = 0.68 s
Square root of
RR = 0.82 QTc = 0.40/0.82 = 0.49 s
Interpretation of intervals? Normal PR and QRS, long QT
I t l
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
84/129
Tip: Instead of calculating the QTc, a quick way to estimate if theQT interval long is to use the following rule:
A QT > half of the RR interval is probably long.
Normal QT Long QT
QT
RR
10 boxes
23 boxes 17 boxes
13 boxes
Rhythm Rate Axis Intervals HypertrophyInfarct
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
85/129
Right atrial enlargement Take a look at this ECG. What do you notice about the P waves?
The P waves are tall, especially in leads II, III and avF.Ouch! They would hurt to sit on!!
Rhythm Rate Axis Intervals Hypertrophy Infarct
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
86/129
Right atrial enlargement To diagnose RAE you can use the following criteria:
II P > 2.5 mm, or
V1 or V2 P > 1.5 mm
Remember 1 small box in height = 1 mm
A cause of RAE is RVH from pulmonary hypertension.
> 2 boxes (in height)
> 1 boxes (in height)
Rhythm Rate Axis Intervals Hypertrophy Infarct
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
87/129
Left atrial enlargement Take a look at this ECG. What do you notice about the P waves?
The P waves in lead II are notched and in lead V1 they have a deep and wide negative component.
Notched
Negative deflection
Rhythm Rate Axis Intervals Hypertrophy Infarct
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
88/129
Left atrial enlargement To diagnose LAE you can use the following criteria:
II > 0.04 s (1 box) between notched peaks , or
V1 Neg. deflection > 1 box wide x 1 box deep
Normal LAE
A common cause of LAE is LVH from hypertension.
Rhythm Rate Axis Intervals Hypertrophy Infarct
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
89/129
Right ventricular hypertrophy Take a look at this ECG. What do you notice about the axis and QRScomplexes over the right ventricle (V1, V2)?
There is right axis deviation (negative in I, positive in II) and there are tall R waves in V1, V2.
Rhythm Rate Axis Intervals Hypertrophy Infarct
h
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
90/129
Right ventricular hypertrophy Compare the R waves in V1, V2 from a normal ECG and one from aperson with RVH.Notice the R wave is normally small in V1, V2 because the right ventricledoes not have a lot of muscle mass.But in the hypertrophied right ventricle the R wave is tall in V1, V2.
Normal RVH
Rhythm Rate Axis Intervals Hypertrophy Infarct
h
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
91/129
Right ventricular hypertrophy To diagnose RVH you can use the following criteria:
Right axis deviation , and
V1 R wave > 7mm tall
A commoncause of RVHis left heart
failure.
Rhythm Rate Axis Intervals Hypertrophy Infarct
h
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
92/129
Left ventricular hypertrophy Take a look at this ECG. What do you notice about the axis and QRScomplexes over the left ventricle (V5, V6) and right ventricle (V1, V2)?
There is left axis deviation (positive in I, negative in II) and there are tall R waves in V5, V6 and deep S waves in V1, V2.
The deep S wavesseen in the leads overthe right ventricle arecreated because theheart is depolarizingleft, superior andposterior (away fromleads V1, V2).
Rhythm Rate Axis Intervals Hypertrophy Infarct
H h
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
93/129
Left ventricular hypertrophy To diagnose LVH you can use the following criteria*:
R in V5 (or V6) + S in V1 (or V2) > 35 mm, oravL R > 13 mm
A common cause of LVHis hypertension.
* There are several other criteria for the diagnosis of LVH.
S = 13 mm
R = 25 mm
Rhythm Rate Axis Intervals Hypertrophy Infarct
H h
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
94/129
A 63 yo man has longstanding, uncontrolled hypertension. Is there evidence of heart disease from his hypertension? (Hint: There a 3 abnormalities.)
Yes, there is left axis deviation (positive in I, negative in II), left atrial enlargement (> 1 x 1 boxes in V1) and LVH (R in V5 = 27 + S in V2 = 10 > 35 mm).
Rhythm Rate Axis Intervals Hypertrophy Infarct
B dl B h Bl k
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
95/129
Bundle Branch Blocks
With Bundle Branch Blocks you will see two changes on theECG.
1. QRS complex widens (> 0.12 sec).2. QRS morphology changes (varies depending on ECG lead, and if
it is a right vs. left bundle branch block).
Ri ht B dl B h Bl k
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
96/129
Right Bundle Branch Blocks
What QRS morphology is characteristic?
V1
For RBBB the wide QRS complex assumes aunique, virtually diagnostic shape in thoseleads overlying the right ventricle (V 1 and V 2).
Rabbit Ears
L ft B dl B h Bl k
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
97/129
Left Bundle Branch Blocks
What QRS morphology is characteristic?
For LBBB the wide QRS complex assumes acharacteristic change in shape in those leadsopposite the left ventricle (right ventricularleads - V 1 and V 2).
Broad,deep Swaves
Normal
Rhythm Rate Axis Intervals Hypertrophy
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
98/129
To diagnose a myocardial infarction you need togo beyond looking at a rhythm strip and obtaina 12-Lead ECG.
RhythmStrip
12-LeadECG
Rhythm Rate Axis Intervals Hypertrophy Infarct
ST El ti
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
99/129
ST Elevation
One way todiagnose an
acute MI is tolook forelevation of theST segment.
ST Ele ation (cont)
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
100/129
ST Elevation (cont)
Elevation of the STsegment (greater
than 1 small box) in2 leads is consistentwith a myocardialinfarction.
Anterior View of the Heart
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
101/129
Anterior View of the Heart
The anterior portion of the heart is best viewedusing leads V 1- V4.
Putting it all Together
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
102/129
Putting it all Together
Do you think this person is having a myocardialinfarction. If so, where?
Other MI Locations
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
103/129
Other MI Locations
Second, remember that the 12-leads of the ECG look at differentportions of the heart. The limb and augmented leads seeelectrical activity moving inferiorly (II, III and aVF), to the left (I,aVL) and to the right (aVR). Whereas, the precordial leads seeelectrical activity in the posterior to anterior direction.
Limb Leads Augmented Leads Precordial Leads
Other MI Locations
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
104/129
Other MI Locations
Now, using these 3 diagrams lets figure where tolook for a lateral wall and inferior wall MI.
Limb Leads Augmented Leads Precordial Leads
Anterior MI
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
105/129
Anterior MI
Remember the anterior portion of the heart is bestviewed using leads V 1- V4.
Limb Leads Augmented Leads Precordial Leads
Lateral MI
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
106/129
Lateral MI
So what leads do you thinkthe lateral portion of theheart is best viewed?
Limb Leads Augmented Leads Precordial Leads
Leads I, aVL, and V 5- V6
Inferior MI
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
107/129
Inferior MI
Now how about the inferiorportion of the heart?
Limb Leads Augmented Leads Precordial Leads
Leads II, III and aVF
Putting it all Together
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
108/129
Putting it all Together
Now, where do you think this person is having amyocardial infarction?
Inferior Wall MI
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
109/129
Inferior Wall MI
This is an inferior MI. Note the ST elevation inleads II, III and aVF.
Putting it all Together
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
110/129
Putting it all Together
How about now?
Anterolateral MI
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
111/129
Anterolateral MI
This persons MI involves both the anterior wall (V 2-V4) and the lateral wall (V 5-V6, I, and aVL)!
ECG Changes
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
112/129
ECG Changes
Ways the ECG can change include:
Appearanceof pathologicQ-waves
T-waves
peaked flattened inverted
ST elevation &depression
ECG Changes & the Evolving
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
113/129
ECG Changes & the EvolvingMI
There are twodistinct patterns
of ECG changedepending if theinfarction is:
ST Elevation (Transmural or Q-wave), or Non-ST Elevation (Subendocardial or non-Q-wave)
Non-ST Elevation
ST Elevation
ST Elevation Infarction
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
114/129
ST Elevation Infarction
ST elevation, peaked T-waves, then T-wave inversion
The ECG changes seen with a ST elevation infarction are:
Before injury Normal ECG
ST elevation & appearance ofQ-wavesST segments and T-waves return tonormal, but Q-waves persist
injury
Infarction
Fibrosis
ST Elevation Infarction
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
115/129
Heres a diagram depicting an evolving infarction: A. Normal ECG prior to MI
B.Injury from coronary artery occlusion results inST depression (not shown) and peaked T-waves
C. Infarction from ongoing ischemia results inmarked ST elevation
D/E. Ongoing infarction with appearance of pathologic Q-waves and T-wave inversion
F. Fibrosis (months later) with persistent Q-waves, but normal ST segment and T- waves
ST Elevation Infarction
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
116/129
Heres an ECG of an inferior MI:
Look at theinferior leads (II,III, aVF).
Question: What ECGchanges doyou see?
ST elevationand Q-wavesExtra credit: What is therhythm? Atrial fibrillation (irregularly irregular with narrow QRS)!
Non-ST Elevation Infarction
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
117/129
Heres an ECG of an inferior MI later in time:
Now what doyou see in theinferior leads?
ST elevation,Q-waves andT-waveinversion
Non-ST Elevation Infarction
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
118/129
ST depression & T-wave inversion
The ECG changes seen with a non-ST elevation infarction are:
Before injury Normal ECG
ST depression & T-wave inversion
ST returns to baseline, but T-waveinversion persists
Ischemia
Infarction
Fibrosis
SUMMARY Rate Rhythm Axis Intervals Hypertrophy Infarct
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
119/129
A 16 yo young man ran into a guardrail while riding a motorcycle.In the ED he is comatose and dyspneic. This is his ECG.
SUMMARY Rate Rhythm Axis Intervals Hypertrophy Infarct
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
120/129
What is the rate? Approx. 132 bpm (22 R waves x 6)
SUMMARY Rate Rhythm Axis Intervals Hypertrophy Infarct
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
121/129
What is the rhythm? Sinus tachycardia
SUMMARY Rate Rhythm Axis Intervals Hypertrophy Infarct
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
122/129
What is the QRS axis? Right axis deviation (- in I, + in II)
SUMMARY Rate Rhythm Axis Intervals Hypertrophy Infarct
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
123/129
What are the PR, QRSand QT intervals?
PR = 0.12 s, QRS = 0.08 s, QTc = 0.482 s
SUMMARY Rate Rhythm Axis Intervals Hypertrophy Infarct
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
124/129
Is there evidence ofatrial enlargement?
No (no peaked, notched or negatively deflected P waves)
SUMMARY Rate Rhythm Axis Intervals Hypertrophy Infarct
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
125/129
Is there evidence ofventricular hypertrophy?
No (no tall R waves in V1/V2 or V5/V6)
SUMMARY Rate Rhythm Axis Intervals Hypertrophy Infarct
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
126/129
Infarct: Are there abnormalQ waves?
Yes! In leads V1-V6 and I, avL
Any
Any
Any
20
30
30
30
3030
30
R40
R50
SUMMARY Rate Rhythm Axis Intervals Hypertrophy Infarct
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
127/129
Infarct: Is the ST elevationor depression?
Yes! Elevation in V2-V6, I and avL.Depression in II, III and avF.
SUMMARY Rate Rhythm Axis Intervals Hypertrophy Infarct
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
128/129
Infarct: Are there T wavechanges?
No
SUMMARY Rate Rhythm Axis Intervals Hypertrophy Infarct
-
8/3/2019 2011-06-17_Belajar EKG (dr.Ika SpJP)
129/129
ECG analysis: Sinus tachycardia at 132 bpm, right axis deviation,long QT, and evidence of ST elevation infarction in the anterolateral leads (V1-V6, I, avL) with reciprocal changes (the ST depression) in the inferior leads (II, III, avF).
This young man suffered anacute myocardial infarction afterblunt trauma. Anechocardiogram showedanteroseptal akinesia in the leftventricle with severely
depressed LV function(EF=28%). An angiogramshowed total occlusion in the