Inhaltsverzeichnis

Vorwort

Preface

Ten years have passed since Twelve Lead Electrocardiography for ACLS Providers was written in response to a need for a clear, concise, introductory level text on the morphologic interpretation of electrocardiograms. This need has grown more compelling in the last decade, as a multiplicity of efficacious therapeutic interventions has made the early recognition of acute coronary syndromes ever more important. The text was developed primarily for physicians, physicians' assistants, nurses, and paramedics who are advanced cardiac life support (ACLS) certified and are already familiar with cardiac dysrhythmias. Therefore, the text deals solely with morphology and does not discuss dysrhythmias.

The need for the first edition was initially spurred by the revolutionary development in the 1980s of thrombolytic therapy for acute myocardial infarction (AMI), and, subsequently, the evolution of percutaneous coronary intervention. The availability of these tools, and their time dependency, has magnified the critical role of first responders and primary care providers in the early recognition and treatment of AMI.

The clinical chapters in this second edition have been extensively rewritten to reflect new concepts in the clinical classification of patients with chest pain, including acute coronary syndrome, and ST and non-ST-segment elevation myocardial infarction. Sections have been added on the diagnosis of AMI in patients with bundle branch block (BBB), and the case presentations have been expanded and updated to better reflect contemporary practice. Additional illustrations and new references have been incorporated.

I have tried to include all of the pertinent information that ACLS providers working in EMS systems, primary care centers, emergency departments, and critical care units will need to know to implement chest pain evaluation protocols and, hopefully, to speed coronary intervention.

In reality, however, the text has proven to be equally valuable to medical students and non-critical care physicians who need a working knowledge of the important fundamentals of morphologic electrocardiography, but who need not become professional electrocardiographers. Thus, the text emphasizes simplicity, clinically useful concepts, and common clinical parlance. It is written in a conversational tone, and is not intended to serve as a reference text for serious postgraduate students of electrocardiography.

Nevertheless, fundamental electrophysiologic principles are emphasized to the extent that students have the opportunity to deduce patterns created by both physiologic and pathologic processes, rather than relying on memorizing electrocardiographic (ECG) patterns of disease. I have tried to communicate the sense of joy that comes from deduction and understanding, as opposed to the drudgery of memorization.

There are many people who played an important role in the writing of this text, primary among whom are the many students who have instructed me in what works and what doesn't over 15 years of teaching electrocardiography. This second edition is my thanks for the joy they have shared with me in learning.

And finally, special thanks go, again, to Lauren Datcher, R.N., whose eagle eyes never fail to defect virtually every one of my ubiquitous manuscript errors.

D. Bruce Foster, DO

Klappentext

Foster

Twelve-Lead
Electrocardiography
Theory and Interpretation
Second Edition

There are two components to the complete interpretation of an electrocardiogram (ECG): analysis of the rhythm of the ECG waveforms that are the electrical manifestation of cardiac activity and analysis of the shape (morphology) of the waveforms in order to diagnose many conditions not related to rhythm. Twelve-Lead Electrocardiography: Theory and Interpretation deals solely with this second component, and it is aimed at medical practitioners and students who already have a familiarity with the analysis of heart rhythms.

Twelve-Lead Electrocardiography: Theory and Interpretation describes a set of discrete building blocks of easily understood electrophysiologic principals, and then allows the reader to deduce what the twelve-lead electrocardiogram will look like under various circumstances. There is no memorizing of patterns. Instead, emphasis is on understanding and deduction. Retention is greatly enhanced, and more importantly, the reader becomes a more competent interpreter of twelve-lead ECGs.

The ultimate objective of the text is to enable both cardiologists and noncardiologists to utilize the twelve-lead ECG in daily clinical practice in a competent manner. Cardiology residents, students, emergency physicians and internists, as well as paramedics, physician assistants, and nurse practitioners who are called upon to make initial clinical judgments, particularly regarding the evaluation of patients with chest pain, will all benefit from the information contained within these pages.

ISBN 978-1-84628-592-9

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Index

A

ACLS (advanced cardiac life support) provider, therapeutic interventions in AMI and, 101-115
ACS (acute coronary syndrome), 98, 126
Acute coronary syndrome. See ACS Alteplase (t-PA), 106
AMI (acute myocardial infarction), 9, 10, 16, 38, 90. See also Infarctions chest pain relating to, 96-98
- diagnosis of, 78-81
- early treatment of, 105
- electrocardiographic categories of NSTEMI, 65, 74-76, 98, 99, 113
- STEMI, 65-67, 68, 69, 98, 99, 100
- localization of, 67-68
- necrosis relating to, 101-102
- pathogenesis of, 101-102
- pathophysiology of, 64-65
- practice tracings relating to, 82-83
- scars relating to, 72-73, 95
- St segment elevation relating to, 65, 66, 68-70, 94, 122
- therapeutic interventions in, 101-115
Angina
- Prinzmetal's, 85
- recumbent or nocturnal, 96
- stable, 95
- unstable, 85, 95-96
- variant, 85
Anginal syndromes, ischemia and, 84-85, 95
Angina pectoris, exertional, 84, 95
Angioplasty, balloon, 103
Antacids, 126, 155
Anterior wall STEMI, 99-100
Antiarrhythmics, 106
Antithrombin drugs, 106
Aspirin, 106
Atria, 2, 3, 5, 6, 13
Atrioventricular node. See AV node Augmented limb leads, 15
AV (atrioventricular) node, 1, 2, 6, 7, 64
Axis. See Electrical axis; LAD;RAD

B

Balloon angioplasty, 103
BBBs (bundle branch block), 90, 123. See also LBBB; RBBB anatomy and pathophysiology of, 42
bifascicular and trifascicular blocks, 52-54
- complete, 42-43
- incomplete, 43
- nonspecific intraventricular conduction delays and, 48-49
- intermittent, supraventricular aberrancy and, 50-51
- LBBB, complete, 8, 40, 45-47
- in V leads, looking for, 44
- practice tracings of, 54-56
- PVCs and paced beats, patterns of, 51-52
- RBBB, complete, 8, 29, 44-45
- ST segments, T waves, and, 47
Beta blockers, 106
Bifascicular blocks, 52-54
Blocks. See also BBBs; Hemiblocks bifascicular, 52-54

- first-degree AV, 7

- trifascicular, 52-54
Bundle branch, 1, 2, 13, 29, 34. See also BBBs

C

Calcium channel antagonists, 106
Cardiac anatomy and physiology, 12-lead ECG relating to, 1-4, 7, 12
Cardiac chambers, muscle mass of, 2-3
Cardiac conduction system, specialized, 1-2, 7
Cardiac vectors 1, 2, 3, 4, 13-14
- depolarization, sequences of, 12-14

- force, 12
- lead systems, 14-16
Chamber enlargement, 90

- force vectors in, 12, 57
- LVH, 58-60

- pathophysiology of, 57

- practice tracings of, 62-63
- RVH, 30, 60-62
Chest pain, 94-100
Coagulation cascade, 103
Coronary arterial circulation, 65
Coronary arteries, anatomy of, 64
Coronary artery spasm, 85
- transmural ischemia and, 86, 96

D

Delta wave, 7, 123
Depolarization, 6, 47
- recording wave of, 2, 3-4, 12
- sequences of, 12-14
- vectors of, 71
- of ventricles, 8, 9, 24, 34
Diffuse low voltage, 122
Digitalis effect, 119-120
Digoxin, 135
Drug-induced ECG changes, 119 12-lead ECG (electrocardiogram), 14.
See also Lead systems cardiac anatomy and

E

- physiology relating to, 1-4, 7, 12
- clinical evaluation of chest pain and acute coronary syndrome relating to, 98
- anterior wall STEMI relating to, 99-100
- history taking relating to, 94-95, 98-99
- inferior wall STEMI relating to, 100
- ischemic heart disease relating to, 95-98
- physical examination relating to, 99
- STEMI, clinical patterns of, relating to, 99
- drug-induced changes to, 119
- grid relating to, 5, 6
- left ventricular pressure curve and, 2 role of, continuous ST segment monitoring and, 100
ECG, normal
- important principles of, 17-18
- lead systems for, 19-22
- three-channel tracings, layout of, 22-23 12-lead

ECG waveforms, 5-11 12-lead ECG grid relating to, 5, 6
- nonspecific St and T wave
- changes, 11
- PR interval relating to, 6-7
- P wave, 5-6, 7, 31
- QRS, 8-9
- QT interval, 11, 116, 117, 119, 120, 121
- ST segment, 9-10
Electrical axis
- axis of P and T waves, 31
- definition of, 24
- determination of 90
- degrees from equally biphasic QRS, 25-27, 28, 30, 36
- deepest S wave, 25
- tallest R wave, 24-25, 26
- two equally tallest R waves, midway between, 27-28
- deviation, significance of, 24, 28-29
- heart, position of, changes to, 30
- indeterminate axis, 30-31
- LAD, major causes of, 30
- practice tracings, 31-33
- RAD, major causes of, 30
- ventricular activation, sequences of, 29
- ventricular muscle mass, changes in, 30
Electrocardiogram. See 12-lead
ECG Electrolyte disturbances, 116
Exercise stress testing, 88-89
Exertional angina pectoris, 84, 95

F

Fascicles, 35
- block of, 40
failure of, 34
Fibrinolysis, prehospital, 112
Fibrinolytics, 106
First-degree AV block, 7
- Force vectors, 12, 57

G

Glycoprotein IIb/IIIa platelet
- aggregation inhibitors, 106

H

Heart, changes to position of, 30
Heart disease. See Ischemic heart disease
Heart failure, classification of, 112
Hemiblocks. See also LAH; LPH

- anatomy of, 34

- fascicles, 34, 35, 40

- practice tracings of, 40-41
Hemibundles, 1, 29
Heparin, 106
Hexaxial reference system, 15-16, 24, 25, 67
Hypercalcemia, 119
Hyperkalemia, 117-119
Hypertrophy, 57
Hypocalcemia, 119
Hypokalemia, 116
Hypothermia, 123-124

I

Infarctions. See also AMI inferior wall myocardial, 38-39
- non-Q wave, 74
- right ventricular AMI, 78
- true posterior AMI, 78
Inferior wall myocardial infarction, 38-39
Inferior wall STEMI, 100
In-hospital protocols, 112-113
Intracranial hemorrhage, 121
Intraventricular conduction delays. See BBBs; Hemiblocks

Ischemia, 146
- anginal syndromes and, 84-85, 95
- electrophysiologic changes during, 85-86
- pathophysiology of, 84
- practice tracings of, 91-93
- silent, 84, 95
- ST abnormalities, differential diagnosis of, 90-91
- ST segment depression, 86-89
- transmural, 86, 96
- T wave inversion relating to, 90
Ischemic heart disease 12-lead ECG relating to, 95-98
- syndromes of AMI, 96-98
- coronary artery spasm and transmural ischemia, 86, 96
- stable angina, 95
- unstable angina, 85, 95-96

J

J point, 9, 123-124
J point depression, 87, 88

L

LAD (left axis deviation), 24, 29, 30, 35, 39, 44, 53, 58
LAH (left anterior hemiblock), 34-36, 37, 38-39, 53, 81
LBBB (left bundle branch block), 8, 40, 45-47, 79-81, 109
Leads, 67-70, 73-83. See also Augmented limb leads;
- Standard limb leads; V leads

Lead systems, 14-16, 19-22. See also Augmented limb

leads; Standard limb leads; V

leads augmented limbs, 15
- hexaxial reference system relating to, 15-16
- standard limbs, 15
Left anterior hemiblock. See LAH

Left axis deviation. See

LAD Left bundle branch block. See LBBB

Left posterior hemiblock. See LPH

Left ventricular hypertrophy. See LVH

Left ventricular pressure curve, 12-lead ECG and, 2
Limb leads. See Augmented limb
leads; Standard limb leads LPH (left posterior hemiblock), 34, 36-38, 54
LVH (left ventricular hypertrophy), 58-60, 62, 87

M

Mean vectors, 13
Myocardial infarction, acute. See AMI

N

Necrosis, 101-102
Nitroglycerin, 106
Nocturnal angina, 96
Non-Q wave infarctions, 74
Nonspecific intraventricular conduction delays, 48-49
Nonspecific ST and T wave changes, 11, 90
NSTEMI, 65, 74-76, 98, 99, 113

O

Osborn waves, 123-124

P

Pathogenesis, of AMI, 101-102
Pathophysiology of AMI, 64-65
- anatomy and, of BBBs, 42
- of chamber enlargement, 57
- of ischemia, 84
PCI (percutaneous coronary intervention), 101, 103-104, 106, 110-111
Percutaneous coronary
- intervention. See PCI

Pericarditis, 122
Pharmacologic reperfusion, 103-110
Plasminogen activators, 106
Potassium, 116-119
Prehospital fibrinolysis, 112
Premature ventricular
- contraction. See PVC

Prinzmetal's angina, 85
Procaineamide, 119
Procaineamide effect, 121
Purkinje fibers, 1, 7, 37
PVC (premature ventricular contraction), 51
P wave, 5, 31

Q

QRS complex
- deflection of, 13, 14
- duration of, 43, 44, 48-49, 57, 61, 121
- equally biphasic, 25-27, 28, 30, 36
- largest on ECG, 8-9
- T wave relating to, 10, 11
Quinidine, 119
Quinidine effect, 120-121
Q wave formation, 65-66, 71-73, 122

R

RAD (right axis deviation), 24, 29, 30, 37, 44, 53, 62
RBBB (right bundle branch block), 8, 29, 44-45, 61, 81
Recording wave, of
- depolarization, 2, 3-4, 12
Recumbent or nocturnal angina, 96
Reperfusion strategies in-hospital protocols for, 112-113
- PCI, 101, 103-104, 106, 110-111, 125
- pharmacologic reperfusion, 103-110
- adjunctive therapy, 106
- thrombolytic agents, 104, 106
- reducing times to, 111-113
- thrombolytic therapy complications of, 107
- contraindications or, 107
- tracing relating to, 108
Repolarization, of ventricles, 10, 11, 14, 47
Reteplase, 106
Right axis deviation. See RAD

Right bundle branch block. See RBBB

Right ventricular AMI, 78
Right ventricular hypertrophy. See RVH

RVH (right ventricular hypertrophy), 30, 60-62, 158
R wave, 24-25, 26, 27-28

S

SA (sinoatrial) node, 1, 2
Scars, AMI relating to, 82-83
Silent ischemia, 84, 95
Sinoatrial node.
See SA node Stable angina, 95
Standard limb leads, 15 I, 20-21, 28, 36-38, 53, 58-63, 6719, 25-28, 38, 39, 59-63, 6720, 22, 23, 25, 26, 35, 37-39, 53, 54, 59-63, 67
Standard limbs, 15
STEMI (ST-segment elevation myocardial infarction), 68, 69, 98, 100, 109.
See also
- AMI; Anterior wall STEMI;
- Infarctions; Inferior wall
STEMI; NSTEMI clinical patterns of, 99
- electrocardiographic hallmarks of, 65-67
Streptokinase, 106
Strip chart recording, 3, 4, 5, 15
ST segment depression, 86-89, 91
ST segment elevation, 65, 66, 68-70, 94, 122.
See also STEMI differential diagnosis of, 70, 76-77
ST segment monitoring, 100
ST segments, 9, 10, 100
- T waves, BBBS and, 47
Summation vectors, 12, 13, 14
S wave, 25

T

Therapeutic interventions, in AMI, 101-115
Three-channel tracings, layout of, 22-23
Thrombolysis, 125
- candidates for, 109-110
Thrombolytic agents, 104, 106
Thrombolytic protocol,
- prehospital, 125
Thrombolytic therapy complications of, 107
- contraindications or, 107
Thrombus formation, 103
Transmural ischemia, 86, 96
Trifascicular blocks, 52-54
True posterior AMI, 78
Turns, 151
T wave inversion, 65, 70, 90, 110
T waves, 10, 11, 31, 47, 90

U

Unstable angina, 85, 95-96

V

Variant angina, 85
Vector 3, 24-25, 34
Vectors. See also Cardiac

vectors 3, 24-25, 34
- depolarization, 71
- force, 12, 57
- mean, 13
- summation, 12, 13, 14
Ventricles
- depolarization of, 8, 9, 24, 34
- repolarization of, 10, 11, 14, 47
Ventricular aneurysm, 78-79, 95
V leads, 15-16, 21-22, 44-50, 58-63, 67, 71, 78, 109

W

Waves, 39
- delta, 7, 123
- Osborn, 123-124
- P, 5, 31
- R, 24-25, 26, 27-28
- S, 25
- T, 10, 11, 31, 47, 90
Wolff-Parkinson-White syndrome. See WPW syndrome

WPW (Wolff-Parkinson-White) syndrome, 123

Autoren

Dr D. Bruce Foster has been teaching electrocardiography for years to various audiences including interns, residents, nurses, paramedics, and in recent years, physician's assistants. In large measure because of ACLS classes, most of them already had a pretty good understanding of dysrhythmias, so his teaching was primarily focused on the morphologic interpretation of ECGs. Absent a text on the market with which he was happy, he created his own course, and ultimately committed it to paper in the form of the first edition.

Reviews

From the reviews: "Acute cardiac syndromes are a major cause of morbidity and mortality, and successful therapy depends upon timely diagnosis which is often made by the ECG. This book is a welcome addition to the body of literature which examines the role of electrocardiography in ACS. It provides first responders with a concise reference for using the ECG to diagnose ACS and choose appropriate therapies in acute care settings." (Scott W. Ard, MD, BS(Ochsner Clinic Foundation), Doody's, June 2007)