Page 1
ECG InterpretationECG Interpretation
William A. Shapiro, M.D.William A. Shapiro, M.D.
http://anesthesia.ucsf.edu/shapirohttp://anesthesia.ucsf.edu/shapiro
Advanced Cardiac Life SupportAdvanced Cardiac Life Support
Department of Anesthesia and Perioperative Care advancing health worldwide TM
Page 2
Course Objectives & Description:Course Objectives & Description:
• Recognize & initiate early management of peri-arrest conditions that may result in cardiac arrest
• Manage cardiac arrest until return of spontaneous circulation, or transfer of care
• Understanding of arrhythmia interpretation
• Recognize the hemodynamic consequencesof arrhythmias
Page 3
Normal Sinus RhythmNormal Sinus Rhythm
Normal sinus rhythm results from the initiation of an Normal sinus rhythm results from the initiation of an
electrical signal (the cardiac impulse) by cells of the electrical signal (the cardiac impulse) by cells of the
sinus node at a rate appropriate to the age and state of sinus node at a rate appropriate to the age and state of
activity of the individual, and then the propagation of activity of the individual, and then the propagation of
that signal in an orderly manner through the atria, A-that signal in an orderly manner through the atria, A-
V junction, ventricular specialized conducting V junction, ventricular specialized conducting
system and the ventricular myocardiumsystem and the ventricular myocardium
Page 4
Cardiac Conduction System Cardiac Conduction System
Bachmann’s bundle
Left bundle branch
Posterior division
Anterior division
Purkinje fibersRight bundle branch
Bundle of His
AV node
Internodal pathways
Sinus node
Page 5
ArrhythmiaArrhythmia
An arrhythmia reflects either abnormally rapid or An arrhythmia reflects either abnormally rapid or
slow impulse initiation by the sinus node, or slow impulse initiation by the sinus node, or
interruption of the sinus rhythm by impulses interruption of the sinus rhythm by impulses
originating from some other site in the heart, originating from some other site in the heart,
either for short or long periods of timeeither for short or long periods of time
Page 6
Mechanisms of ArrhythmiasMechanisms of Arrhythmias
•Reentry
•Automaticity–Altered normal automaticity–Abnormal automaticity
•Triggered Rhythms due to DAD (delayed after depolarizations
Page 7
Causes of ArrhythmiasCauses of Arrhythmias
• Physiologic and Pathologic Processes–Vagal stimulation, Fever, Hypothermia
–Electrolyte abnormalities, CNS problems
–Hypovolemia, Pain, anaphylaxis, etc.
• Preexisting Cardiac & Pulmonary Disease–Acute coronary syndrome, HTN, AODM
–COPD, hypoxia, hypercarbia
Page 8
The ElectrocardiogramThe Electrocardiogram
QuickTime™ and a decompressor
are needed to see this picture.
Page 9
QuickTime™ and a decompressor
are needed to see this picture.
PR Interval
QRS Interval
The ElectrocardiogramThe Electrocardiogram
Q
R
S
TP U
Page 10
QuickTime™ and a decompressor
are needed to see this picture.
PR Interval
QRS Interval
QT Interval
The ElectrocardiogramThe Electrocardiogram
Page 11
Relationship of ECG to anatomy
Cardiac Conduction System Cardiac Conduction System
Page 12
Relationship of ECG to anatomy
Cardiac Conduction System Cardiac Conduction System
Page 13
THE ACLS THE ACLS
PROVIDER PROVIDER
IS:IS: IN
ACLS
Page 14
Normal Sinus Rhythm Normal Sinus Rhythm
•Rate 60-100 beats per minute
•Rhythm: Regular
•P waves: Upright in Leads: 1, 2, AVF
Page 15
Determining the RateDetermining the Rate
Page 16
Determining the RateDetermining the Rate
QuickTime™ and a decompressor
are needed to see this picture.
Page 17
Determining the RhythmDetermining the Rhythm
Page 18
Sinus Tachycardia Sinus Tachycardia
•Rate: Greater than 100 beats per minute
•Rhythm: Regular
•P waves: Upright in Leads: 1, 2, AVF
Page 19
Sinus Tachycardia Sinus Tachycardia
•Rate: Greater than 100 beats per minute
•Rhythm: Regular
•P waves: Upright in Leads: 1, 2, AVF
QuickTime™ and a decompressor
are needed to see this picture.
QuickTime™ and a decompressor
are needed to see this picture.
Page 20
Sinus Bradycardia Sinus Bradycardia
•Rate: Less than 60 beats per minute
•Rhythm: Regular
•P waves: Upright in Leads: 1, 2, AVF
Page 21
Sinus Bradycardia Sinus Bradycardia
•Rate: Less than 60 beats per minute
•Rhythm: Regular
•P waves: Upright in Leads: 1, 2, AVF
Page 22
Premature Atrial Complexes Premature Atrial Complexes
QuickTime™ and a decompressor
are needed to see this picture.
QuickTime™ and a decompressor
are needed to see this picture.
•P wave Rhythm: Irregular
•P waves: Premature, often in the T-wave
•QRS complex: Normal or widened
P-wave
Page 23
Premature Atrial Complexes Premature Atrial Complexes
•P wave Rhythm: Irregular
•P waves: Premature, often in the T-wave
•QRS complex: Normal or widened
QuickTime™ and a decompressor
are needed to see this picture.
Page 24
Premature Atrial Complexes Premature Atrial Complexes
•P wave Rhythm: Irregular
•P waves: Premature, often in the T-wave
•QRS complex: (Normal or widened) or blocked
QuickTime™ and a decompressor
are needed to see this picture.
Non conducted P-wave
Page 25
Atrial TachycardiaAtrial Tachycardia
• Rate: Atrial- 140-240 bpm, p-waves hard to see
• Rhythm: – P-wave- regular
– QRS- 1-1 conduction with atrial rates < 200 bpm
– With atrial rates > 200 bpm, A-V conduction block common (less than 1-1 conduction)
• PR interval- depends on the origin of the p-wave
• QRS- usually normal
Page 26
Atrial TachycardiaAtrial Tachycardia
QuickTime™ and a decompressor
are needed to see this picture.
QuickTime™ and a decompressor
are needed to see this picture.
P-Wave
QuickTime™ and a decompressor
are needed to see this picture.
P-Wave
Page 27
Atrial TachycardiaAtrial Tachycardia
Atrial Tachycardia with variable block
QuickTime™ and a decompressor
are needed to see this picture.
P-Waves are regular at 160 bpm
Page 28
Atrial FlutterAtrial Flutter
• Rate: Atrial- 300 bpm (260-320)
• Rhythm: – P-waves- regular
– QRS- 2-1 conduction - 150 bpm, variable AV conduction with constant AV conduction ratio
• P-waves: F-waves (Flutter), sawtooth pattern
• QRS- usually normal, obviously sometimes wide
Page 29
Atrial FlutterAtrial Flutter
QuickTime™ and a decompressor
are needed to see this picture.
QuickTime™ and a decompressor
are needed to see this picture.
QuickTime™ and a decompressor
are needed to see this picture.
QuickTime™ and a decompressor
are needed to see this picture.
F-waves
Page 30
Atrial FlutterAtrial Flutter
Atrial Flutter with variable conduction (block)
Page 31
Atrial FibrillationAtrial Fibrillation
• Rate: Atrial- rapid, Ventricular- Depends
• Rhythm: – P-waves- irregular
– QRS- beat to beat variability, Irregularly irregular
• P-waves: From F-waves (Flutter) to absent
• QRS duration- normal or wide
Page 32
Atrial FibrillationAtrial Fibrillation
QuickTime™ and a decompressor
are needed to see this picture.
QuickTime™ and a decompressor
are needed to see this picture.
Page 33
Atrial FibrillationAtrial Fibrillation
QuickTime™ and a decompressor
are needed to see this picture.
QuickTime™ and a decompressor
are needed to see this picture.
Page 34
Atrial FibrillationAtrial Fibrillation
Page 35
Premature Junctional ComplexesPremature Junctional Complexes
•Rhythm: Irregular
•P waves: Retrograde
•PR interval: < .12 sec or nonexistent
•QRS complex: Normal or widened
QuickTime™ and a decompressor
are needed to see this picture.
Page 36
Premature Ventricular ComplexesPremature Ventricular Complexes
•Rhythm: Irregular
•P waves: Usually not seen
•QRS complex: Wide > .12 sec
•Compensatory pause
QuickTime™ and a decompressor
are needed to see this picture.
Page 37
Premature Ventricular ComplexesPremature Ventricular Complexes
Compensatory pause
QuickTime™ and a decompressor
are needed to see this picture.
This distanceis double the
sinus distance
This is the sinus and the QRSdistance
Page 38
Premature Ventricular ComplexesPremature Ventricular Complexes
QuickTime™ and a decompressor
are needed to see this picture.
QuickTime™ and a decompressor
are needed to see this picture.
•Unifocal PVCs
•Multifocal PVCs
Page 39
Premature Ventricular ComplexesPremature Ventricular Complexes
Compensatory pause
QuickTime™ and a decompressor
are needed to see this picture.
This distanceis double the
sinus distance
This is the sinus and the QRSdistance
Interpolated PVC
QuickTime™ and a decompressor
are needed to see this picture.
Page 40
Premature Ventricular ComplexesPremature Ventricular Complexes
Ventricular Bigeminy
Pairs of PVCs
QuickTime™ and a decompressor
are needed to see this picture.
QuickTime™ and a decompressor
are needed to see this picture.
Page 41
Premature Ventricular ComplexesPremature Ventricular Complexes
QuickTime™ and a decompressor
are needed to see this picture.
PVC on T-wave precipitating Ventricular Tachycardia
Page 42
Ventricular TachycardiaVentricular Tachycardia
•Rate: Approx 100-230 bpm
•Rhythm: Usually regular
•P waves: Usually not seen
– Independent A and V activity
– A-V dissociation
•QRS complex: Wide > .12 sec
•Capture beats, fusion beats
Page 43
QuickTime™ and a decompressor
are needed to see this picture.
QuickTime™ and a decompressor
are needed to see this picture.
Ventricular TachycardiaVentricular Tachycardia
Page 44
Ventricular TachycardiaVentricular Tachycardia
Polymorphic Ventricular Tachycardia
Page 45
Ventricular FibrillationVentricular Fibrillation
•Rate: Rapid- no effective cardiac rhythm
•Rhythm: Irregular
•P, QRS, T- waves: Absent
•No blood pressure!
Page 46
Ventricular FibrillationVentricular Fibrillation
Course VF
Fine VF
Page 47
Ventricular FibrillationVentricular Fibrillation
Page 48
Ventricular AsystoleVentricular Asystole
•P, QRS, T- waves: Complete absent of cardiac electrical activity
•Complete absent of effective cardiac pumping function
Page 49
QuickTime™ and a decompressor
are needed to see this picture.
Acute Coronary SyndromesAcute Coronary Syndromes
Page 50
Acute Coronary SyndromesAcute Coronary Syndromes
Page 51
Acute Coronary SyndromesAcute Coronary Syndromes
Page 53
ReviewReview
Atrial Fibrillation
Page 54
ReviewReview
Atrial Fibrillation
Sinus Rhythm
Page 55
ReviewReview
Atrial Fibrillation
Sinus Rhythm
Acute Coronary Syndrome
Page 57
ReviewReview
Asystole
Page 58
ReviewReview
Asystole
Fine Ventricular Fibrillation
Page 59
ReviewReview
Asystole
Fine Ventricular Fibrillation
Coarse Ventricular Fibrillation
Page 61
ReviewReview
Ventricular Tachycardia- ?
Page 62
ReviewReview
Premature Ventricular Complex (PVC)
Ventricular Tachycardia- ?
Page 63
ReviewReview
Premature Ventricular Complex (PVC)
Ventricular Tachycardia
Ventricular Tachycardia- ?
Page 65
ReviewReview
Ventricular Tachycardia
Page 66
ReviewReview
Ventricular Tachycardia
Ventricular Tachycardia
Page 67
ReviewReview
Ventricular Tachycardia
Ventricular Tachycardia
(Paroxsymal) Atrial Tachycardia (SVT)
Page 69
ReviewReview
Paroxsymal Atrial Tachycardia (SVT)
Page 70
ReviewReview
Paroxsymal Atrial Tachycardia (SVT)
Atrial Flutter
Page 71
Treatment of All Cardiac Arrhythmias
Treatment of All Cardiac Arrhythmias
All arrhythmias that are
hemodynamically significant
require immediate
cardioversion, defibrillation,
or cardiac pacing
Page 73
AV BlockAV Block
•Why is it important?
•Where is the block?
•What’s a pacemaker anyway?
Page 74
Rates of Intrinsic Cardiac Pacemakers
Rates of Intrinsic Cardiac Pacemakers
•Primary pacemaker
–Sinus node (60-100 bpm)
•Escape pacemakers
–AV junction (40-60 bpm)
–Ventricular (< 40 bpm)
Page 75
Escape PatternsEscape Patterns
Page 76
Junctional Escape ComplexesJunctional Escape Complexes
•Rate: Junctional escape rate 40-60 bpm
•Rhythm: Junctional
•P-waves: Retrograde, inverted in 2,3, avf
–Before, during, or after QRS
•QRS: Normal or wide
Page 77
Junctional Escape ComplexesJunctional Escape Complexes
QuickTime™ and a decompressor
are needed to see this picture.
Page 78
Junctional Escape ComplexesJunctional Escape Complexes
Junctional Rhythm
QuickTime™ and a decompressor
are needed to see this picture.
Page 79
Ventricular Escape ComplexesVentricular Escape Complexes
QuickTime™ and a decompressor
are needed to see this picture.
QuickTime™ and a decompressor
are needed to see this picture.
QuickTime™ and a decompressor
are needed to see this picture.
Page 80
Classification of AV BlockClassification of AV Block
•Partial– First-degree AV block– Second-degree AV block,
Types I (Wenckebach) and Type II
•Complete AV block– Third-degree AV Block
“You should know the major AV blocks because important treatment decisions are based on the type of block present.” Page 79
Page 81
First-Degree AV BlockFirst-Degree AV Block
•Rhythm: Regular
•1:1 Conduction: Each P-wave is followed by a QRS complex
•PR Interval: > .20 secs
•QRS Complex: Generally normal
•Hemodynamic implications: None
Page 82
First-Degree AV BlockFirst-Degree AV Block
Page 83
Second-Degree AV Block, Type ISecond-Degree AV Block, Type I
• Rate: – Atrial- regular– Ventricular- less than the atrial rate
• Rhythm: – Atrial- regular– Ventricular- progressive shortening of
the R-R interval before pause• PR: progressive increase until P blocked
• Why is knowing this important
Page 84
Second-Degree AV Block, Type ISecond-Degree AV Block, Type I
QuickTime™ and a decompressor
are needed to see this picture.
Page 85
Second-Degree AV Block, Type IISecond-Degree AV Block, Type II
• Rate: – Atrial- regular– Ventricular- less than the atrial rate
• Rhythm: – Atrial- regular– Ventricular- usually irregular
• PR: constant when present• Why is knowing this important
Page 86
Second-Degree AV Block, Type IISecond-Degree AV Block, Type II
QuickTime™ and a decompressor
are needed to see this picture.
Page 87
Third-Degree AV Block Third-Degree AV Block
• Rate: – Atrial- regular– Ventricular- less than the atrial rate
• Rhythm: – Atrial- regular– Ventricular- regular
• PR: varies with every beat• QRS: normal or wide• Hemodynamics: No atrial contribution
Page 88
Third-Degree AV Block Third-Degree AV Block
Page 89
Third-Degree AV Block Third-Degree AV Block
Page 90
All arrhythmias that are
hemodynamically significant
require immediate
cardioversion, defibrillation,
or cardiac pacing
Electrical TherapyElectrical Therapy
Page 91
• Understand when cardioversion or defibrillation is indicated
• Know the difference between unsynchronized and synchronized shocks
• Energy doses for specific rhythms
• Challenges of delivering shocks safely and effectively- may include iv sedation
Electrical TherapyElectrical Therapy
Page 92
Cardioversion and DefibrillationCardioversion and Defibrillation
• Understand when cardioversion or
defibrillation is indicated
SYMPTOMS
SYMPTOMS
SYMPTOMS
Page 93
Hemodynamically SignificantHemodynamically Significant
Tachycardia or Bradycardia
• Hypotension (Systolic BP < 80 mmHg)
• Altered mental status
• Congestive heart failure
• Angina
• Does not respond promptly to medical
management, if tried
Page 94
Cardioversion and DefibrillationCardioversion and Defibrillation
Defibrillation
The electric shock depolarizes all
excitable myocardium, interrupts
reentrant circuits, discharges
foci, and establishes electrical
homogeneity
Page 95
Cardioversion and DefibrillationCardioversion and Defibrillation
Defibrillation
• AED: Learn the one in your setting
• Biphasic: 200 watt-seconds (joules)
• Monophasic: 360 watt-seconds (joules)
“The interval from collapse to defibrillation is
one of the most important determinants of
survival from cardiac arrest.” Page 35
Page 96
Cardioversion and DefibrillationCardioversion and Defibrillation
Page 97
Cardioversion and DefibrillationCardioversion and Defibrillation
• Power on
• Apply pads
• Analyze the rhythm
• Select the energy level
• Clear the area
• Discharge the device
Procedure for Defibrillation
Page 98
Cardioversion and DefibrillationCardioversion and Defibrillation
Cardioversion
• Know when cardioversion is indicated
• Synchronized vs unsynchronized shock
• What energy level for what arrhythmias
• Establish iv and consider sedation
Page 99
Cardioversion and DefibrillationCardioversion and Defibrillation
Cardioversion
A physician skilled in airway management
(ie., an anesthesiologist) should be in
attendance, and all necessary equipment
for emergency resuscitation should be
immediately available
Anesthetic (amnestic) Agents
Page 100
Cardioversion and DefibrillationCardioversion and Defibrillation
Cardioversion
The electric shock depolarizes all
excitable myocardium, interrupts
reentrant circuits, discharges
foci, and establishes electrical
homogeneity
Page 101
Cardioversion and DefibrillationCardioversion and Defibrillation
Synchronization
Synchronized cardioversion (defibrillation) uses
a sensor to deliver the shock with the peak of the
QRS complex. The goal is to avoid the shock on
the T-wave, “R-on-T”, which is known to induce
ventricular fibrillation in unstable hearts
Page 102
QuickTime™ and a decompressor
are needed to see this picture.
PR Interval
QRS Interval
QT Interval
The ElectrocardiogramThe Electrocardiogram
Page 103
• Atrial flutter & SVT: 50-100 J (monphasic)
• Atrial fibrillation: 100-200 J (monophasic)
• Ventricular tachycardia: 100-200 J
Cardioversion and DefibrillationCardioversion and Defibrillation
Synchronization
Energy Selection
Page 104
Cardioversion and DefibrillationCardioversion and Defibrillation
• Power on
• Apply pads
• Turn on the SYNC control
• Analyze the rhythm
• Select the energy level
• Clear the area
• Discharge the device
Procedure for Cardioversion
Page 105
Cardioversion and DefibrillationCardioversion and Defibrillation
• Ventricular fibrillation occurs
• Turn off the SYNC control
• Charge to 200 J (or more)
• Clear the area
• Discharge the device
Complications of Cardioversion
Page 107
ReviewReview
3rd Degree Heart Block
Page 108
ReviewReview
3rd Degree Heart Block
2nd Degree Type II Block
Page 109
ReviewReview
3rd Degree Heart Block
2nd Degree Type II Block
2nd Degree Type I Block
Page 111
ReviewReview
1st Degree Heart Block
Page 112
ReviewReview
Junctional Escape Rhythm
1st Degree Heart Block
Page 113
ReviewReview
Junctional Escape RhythmJunctional Escape Rhythm
Sinus Bradycardia
1st Degree Heart Block
Page 114
QuickTime™ and a decompressor
are needed to see this picture.
ReviewReview
Ventricular Tachycardia- ?
Page 116
ECG InterpretationECG Interpretation
William A. Shapiro, M.D.William A. Shapiro, M.D.http://anesthesia.ucsf.edu/shapirohttp://anesthesia.ucsf.edu/shapiro
Advanced Cardiac Life SupportAdvanced Cardiac Life Support
Department of Anesthesia and Perioperative Care advancing health worldwide TM
That’s it- Now go forthThat’s it- Now go forthand save lives-and save lives-
Make us all proud you’re from UCSFMake us all proud you’re from UCSF