Offers a guide for a complete understanding of the disease and conditions most frequently revealed in ECGs recorded in the acute, critical, and emergency care settings
Electrocardiogram in Clinical Medicine offers an authoritative guide to ECG interpretation that contains a focus and perspective from each of the three primary areas of medical care: acute care, critical care and emergency care. It can be used as a companion with the book ECGs for the Emergency Physician I & II (by Mattu and Brady) or as a stand-alone text. These three books can be described as a cumulative EGG reference for the medical provider who uses the electrocardiogram on a regular basis.
Electrocardiogram in Clinical Medicine includes sections on all primary areas of ECG interpretation and application as well as sections that highlight use, devices and strategies. The medical content covers acute coronary syndromes and all related issues, other diseases of the myocardium, morphologic syndromes, toxicology and paediatrics; dysrhythmias will also be covered in detail. This important resource:
• Goes beyond pattern recognition in ECGs to offer a real understanding of the clinical syndromes evidenced in ECGs and implications for treatment
• Covers the indications, advantages and pitfalls of the use of ECGs for diagnosis in all acute care settings, from EMS to ED to Critical Care
• Examines the ECG in toxic, metabolic and environmental presentations; critical information for acute care clinicians who need to be able to differentiate ODs, poisoning and other environmental causes from MI or other cardiac events
• Facilitates clinical decision-making
Written for practicing ER, general medicine, family practice, hospitalist and ICU physicians and medical students, Electrocardiogram in Clinical Medicine is an important book for the accurate interpretation of EGG results.
Table of Contents
List of Contributors xxi
Section I The ECG in Clinical Practice 1
1 The ECG in Clinical Medicine 3
Brian Kessen and Kelly Williamson
Introduction 3
The ECG as a Clinical Tool 3
Clinical Presentations and the ECG 4
Chest Pain 4
Dyspnea 5
Syncope 6
Toxicology 7
Electrolyte Abnormalities 7
Pacemakers 10
Conclusion 10
References 10
2 History of the Electrocardiogram 13
Trale Permar and Kelly Williamson
References 17
Section II ECG Changes in Myocardial Ischemia 19
1 The Cardiac Action Potential and Changes in the Setting of Acute Coronary Syndrome: How Ischemia and Infarction Impacts the ECG 21
Kirsti A. Campbell and Michael J. Lipinski
Introduction 21
Basic Electrophysiology 21
Action Potentials in Sodium-Dependent Depolarizers 21
Action Potential in Calcium-Dependent Depolarizers 24
Anatomy of the Electrical Conduction System 24
Biochemical Impact of Ischemia 25
ST-Segment Deviation 25
QRS Complex 30
T Waves 31
P Waves 31
U Waves 34
Myocardial Ischemia: Causes Other than Acute Coronary Syndrome 34
Conclusion 34
References 36
2 Ischemic Electrocardiographic Changes and Correlation with Regions of the Myocardium 37
Thibault Lhermusier and Michael J. Lipinski
Introduction 37
Coronary Anatomy 37
Definitions of STEMI and Non-ST Elevation ACS 38
Left Main Coronary Ischemia 39
Anterior STEMI 40
Wellens Syndrome 40
Inferior STEMI 41
Right Ventricular Infarction 41
Lateral STEMI 44
Posterior STEMI 44
Conduction Abnormalities in the Setting of Ischemia 46
Aneurysm of the Left Ventricle 49
ECG in Pharmacological and Mechanical Reperfusion 49
Conclusion 50
References 50
3 STEMI Mimics 53
Peter M. Pollak
Introduction 53
Myocarditis and Myopericarditis 53
Early Repolarization 55
Left Ventricular Hypertrophy 57
Prior Infarction and Ventricular Aneurysm 58
Vasospasm (Prinzmetal or Variant Angina) 58
Apical Ballooning Syndrome (Takotsubo Cardiomyopathy) 61
Brugada Pattern and Idiopathic Ventricular Fibrillation 62
Hyperkalemia 62
Post-Cardioversion/Shock 62
Hypothermia and Osborn Waves 62
Pulmonary Embolism 63
Other Causes of ST Elevation 63
Conclusion 65
References 65
4 Confounders of ST‐Elevation Myocardial Infarction 69
Amy West Pollak
Introduction 69
Left Bundle Branch Block 69
LBBB and Ischemic Heart Disease 69
Left Ventricular Hypertrophy 71
Ventricular Paced Rhythm 71
Right Bundle Branch Block (RBBB) 73
References 73
5 The Prognostic Value of the Electrocardiogram in Acute Coronary Syndromes 75
Benjamin Shepple and Robert Gibson
Introduction 75
The ECG in Acute Coronary Syndromes 75
ST Elevation Myocardial Infarction (STEMI) 75
The ECG during Myocardial Injury 76
The ECG in Response to Therapy 80
ECG after Completion of Infarction 81
UA/NSTEMI 83
ST-Segment Depression 83
T-Wave Inversions 84
Initial Normal ECG 86
Arrhythmia and Conduction Disease 86
Ventricular Arrhythmias 86
Premature Ventricular Contractions 87
Ventricular Tachycardia 87
Ventricular Fibrillation 87
Supraventricular Tachycardia 89
AV Conduction Delay and Heart Block 90
Prolonged QTc Interval 91
Conclusion 92
References 92
6 ECG Tools: Alternate Lead Placement, Serial ECGs, and ECG Monitoring 97
Augustus E. Mealor, Yasir Akhtar, and Michael Ragosta
Introduction 97
Right-Sided Leads 97
Posterior ECG 99
Serial ECG Monitoring 101
STM-ECG 101
Serial ECG Monitoring 101
References 105
7 Electrocardiographic Changes of Ischemia during Stress Testing 107
Michael J. Lipinski and Victor F. Froelicher
Introduction 107
Exercise Physiology 108
Normal ECG Changes with Exercise 108
ECG Changes with Ischemia 109
Women 114
Diagnostic Scores 114
Termination of Exercise Testing 114
Exercise Testing and Acute Coronary Syndromes 117
Exercise Testing after Myocardial Infarction 117
Recommended Reading 120
Conclusions 120
References 120
Section III The Dysrhythmic ECG 123
1 Bradycardia 125
Andrew E. Darby
Introduction 125
Abnormalities of Sinus Node Function 125
Abnormalities of Atrioventricular Nodal Conduction 126
Indications for Cardiac Pacing 131
Conclusions 131
References 132
2 Atrioventricular (AV) Block 133
Mark Marinescu and Andrew E. Darby
First-Degree AV Block 133
Second-Degree AV Block 133
Third-Degree AV Block 137
Indications for Permanent Pacing 137
Conclusions 138
References 138
3 The Dysrhythmic ECG: Intraventricular Block 141
Andrew E. Darby
Introduction 141
Anatomy and Electrophysiology 141
Right Bundle Branch Block 141
Left Bundle Branch Block 143
Nonspecific Intraventricular Conduction Delay 145
Fascicular Block 145
References 146
4 Narrow QRS Complex Tachycardia 149
Augustus E. Mealor and Andrew E. Darby
Introduction 149
Approach to the ECG Diagnosis of NCT 150
The Regular Narrow Complex Tachycardias 151
Paroxysmal Supraventricular Tachycardia 154
The Irregular Narrow Complex Tachycardias 158
References 160
5 Wide QRS Complex Tachycardia 161
Andrew E. Darby
Ventricular Tachycardia 161
Ventricular Paced Rhythm 164
Diagnosis of Wide QRS Complex Tachycardia by Electrocardiogram 166
Conclusions 167
References 167
6 Non-Sinus Rhythms with Normal Rates 169
Will Dresen and Andrew E. Darby
Introduction 169
Ectopic Atrial Rhythm 169
Accelerated Idioventricular Rhythm (AIVR) 172
Conclusions 172
References 172
7 Rhythms of Cardiac Arrest 173
Erich Kiehl and Andrew E. Darby
Introduction 173
Torsade de Pointes 174
Preexcited Atrial Fibrillation 174
Pulseless Electrical Activity 177
Conclusions 179
References 179
8 Premature Atrial and Ventricular Complexes 181
Adrián I. Löffler and Andrew E. Darby
Premature Atrial Contractions 181
Premature Ventricular Contractions 184
References 186
9 Nontraditional Rhythm Disorders: Dysrhythmias Related to Metabolic and Toxicologic Conditions 187
Andrew E. Darby
Introduction 187
Antiarrhythmic Drug Toxicity 188
Tricyclic Antidepressant Toxicity 190
Conclusions 191
References 192
10 Dysrhythmia-Related Syndromes 193
Michele Murphy and Andrew E. Darby
Introduction 193
Dysrhythmia-Related Syndromes - Primary Electrical Abnormalities 193
Wolff-Parkinson-White Syndrome 193
Dysrhythmia-Related Syndromes - Primary Cardiac Structural Conditions 197
Conclusions 199
References 200
Section IV The ECG in Cardinal Presentations and Scenarios 201
1 The Patient with Cardiac Arrest 203
Michael Cirone, Mitchell Lorenz, and Karis Tekwani
Introduction 203
Ventricular Fibrillation 203
Pulseless Ventricular Tachycardia 203
Asystole 205
Pulseless Electrical Activity 205
Conclusion 206
References 206
2 The Patient with Chest Pain 207
Paul Basel, Lane Thaut, and Nathan Olson
Introduction 207
Acute Coronary Syndrome 207
Pericarditis 213
References 215
3 The Patient with Dyspnea 219
Adriana Segura Olson, Anders Messersmith, and Matthew Robinson
Introduction 219
Pulmonary Embolism 219
Cor Pulmonale 220
Cardiomyopathy 220
Congestive Heart Failure 223
Pneumothorax 223
ASTHMA/COPD 224
Anaphylaxis/Kounis Syndrome 225
Metabolic 226
Summary 227
References 227
4 The Patient with Palpitations/Syncope 229
Natasha Wheaton, Emma Nash, and Jeffrey Brown
Supraventricular Tachycardia 229
Atrial Fibrillation 229
Multifocal Atrial Tachycardia 230
Conduction Blocks 232
Brugada Syndrome 233
Hypertrophic Cardiomyopathy 234
Wolf-Parkinson-White Syndrome 234
Long QT Syndrome 236
Arrhythmogenic Right Ventricular Dysplasia 237
References 237
5 The Patient with Preoperative Evaluation 239
Sarah Chuzi, Jane Wilcox, and Lisa B. Van Wagner
Introduction 239
Indications 239
Common ECG Abnormalities 239
Nonspecific ST-T Changes 244
Pathologic Q Waves 244
QT/QTc Prolongation 245
Conclusion 245
References 246
6 The Patient in Shock 249
Meagan R. Hunt and Nicholas D. Hartman
Introduction 249
Cardiogenic Shock 249
Obstructive Shock 252
Distributive Shock 252
Hypovolemic Shock 262
Summary 262
References 263
7 The Patient with Overdose 265
Ashley Pastore and Andrea Carlson
Introduction 265
Approach to the ECG in the Poisoned Patient 265
Classic Toxicology ECGs 267
Drug-Induced SVT 268
Brugada Pattern 268
Tricyclics Antidepressants 268
Calcium Channel Blockers 272
Conclusion 273
References 274
Section V The ECG in Poison, Electrolyte, Metabolic and Environmental Emergencies 275
1 ECG Diagnosis and Management of the Poisoned Patient 277
William F. Rushton and Christopher P. Holstege
Introduction 277
Cardiac Action Potential 277
Tachycardia in the Poisoned Patient 277
Bradycardia 278
QRS Prolongation 279
QT Prolongation 282
Conclusion 283
References 284
2 The Use of the ECG in the Poisoned Patient: The “Rule-out Ingestion” Strategy 287
Heather A. Borek and Lewis S. Hardison
Introduction 287
Background 287
Rate 287
Rhythm 289
Morphology of the Cardiac Action Potential and the ECG 290
QRS Interval Prolongation 290
QTc Interval Prolongation 292
Timing 293
The Undifferentiated Patient 294
Conclusion 294
References 295
3 The ECG and Electrolyte Abnormalities 297
Justin Rizer, Joshua D. King, and Nathan P. Charlton
Introduction 297
Calcium 297
Hypocalcemia 297
Hypercalcemia 298
Magnesium 298
Hypomagnesemia 299
Potassium 300
Hyperkalemia 300
Hypokalemia 303
References 305
4 The ECG and Metabolic Abnormalities 307
George F. Glass, Amita Sudhir, and Amit Anil Kumar Pandit
Introduction Metabolic Disturbances and the ECG 307
ECG Findings During Acute Complications of Diabetes Mellitus 307
Disturbances Due to Alterations of pH 309
Other Metabolic Conditions 311
References 311
5 The ECG in Environmental Urgencies and Emergencies 315
Heather T. Lounsbury and Seth O. Althoff
Introduction 315
Hypothermia 315
Lightning Strikes 319
Underwater Submersion 321
Heat Stroke 322
Conclusion 324
References 324
Section VI The ECG in Special Inpatient Groups 327
1 The ECG-Monitored Patient 329
Feras Khan
Introduction 329
Clinical Scenarios Requiring Telemetry/Electrocardiographic Monitoring 329
Conclusion 332
References 334
2 Electrocardiography in the Operating Room 335
Feras Khan
Introduction 335
Types of Monitoring 335
Risks for Arrhythmias in the OR 335
Postoperative Electrocardiographic Abnormalities 335
Initial Management and ECG Evaluation 335
Types of Arrhythmias 336
Specific Clinical Conditions 341
Conclusion 342
References 343
3 ECG in the ICU Patient: Identification and Treatment of Arrhythmias in the Intensive Care Unit 345
Feras Khan
Introduction 345
Common Dysrhythmias in the ICU 345
Other Common Electrocardiographic Findings 352
The Effect of Vasopressors on Cardiac Conduction 352
Consequences of Anti-Arrhythmic Medications 353
Arrhythmias Induced by Central Line Placement 354
Specific Clinical Conditions 354
Conclusion 357
References 357
4 The ECG in Patients with Implanted Cardiac Devices 359
Ali Farzad, Benjamin J. Lawner, and Tu Carol Nguyen
Basics of Pacemakers 359
Electrocardiographic Findings in Normally Functioning Pacemakers 360
Electrocardiographic Findings in Abnormally Functioning Pacemakers 361
Key Points: Electrocardiographic Clues to Pacemaker Malfunction 368
Electrocardiographic Diagnosis of Acute Myocardial Infarction in the Presence of a Paced Rhythm 368
Basics of the Implantable Cardioverter Defibrillator 370
Electrocardiographic Findings after Defibrillation 370
Basics of Left Ventricular Assist Devices 371
References 375
5 Electrocardiographic Manifestations of Cardiac Transplantation 377
Semhar Tewelde
Introduction 377
Cardiac Transplantation 377
Conclusion 80
Key Points 380
References 380
Section VII Electrocardiographic Differential Diagnosis 383
1 Abnormalities of the P Wave and PR Interval 385
Matthew Borloz
The Normal P Wave 385
The Abnormal P Wave 385
The Normal PR Interval 387
The Abnormal PR Interval 387
Conclusion 395
References 395
2 Differential Diagnosis of QRS Complex Abnormalities 397
Matthew Wilson, Michael Ybarra, and Munish Goyal
QRS Complex Abnormalities 397
The Large QRS Complex 397
The Small QRS Complex 398
The Wide QRS Complex 399
References 405
3 Differential Diagnosis of ST Segment Changes 407
Korin Hudson and Norine McGrath
Introduction 407
Describing ST-Segment Changes 407
Acute Coronary Syndrome and Related ST Segment Deviation 408
Nonischemic Causes of ST-Segment Changes 412
Benign Early Repolarization 414
Acute Myocarditis/Pericarditis 415
Ventricular Aneurysm 416
Digitalis 416
Hypothermia 417
Hyperkalemia 417
Brugada Syndrome 417
Tachycardia-Related STD 418
CNS Injury 418
Other Causes 418
References 419
4 ECG Differential Diagnosis of T Wave and QT Interval Abnormalities 421
Sanjay Shewakramani and Kari Gorder
The T Wave 421
Prominent T Waves 421
Benign Early Repolarization 422
T-Wave Inversions 422
The QT Interval 427
QT Prolongation 428
Congenital Long QT Syndrome 429
Short QT Interval 429
Congenital Short QT Syndrome 429
References 429
5 Bradycardia 433
B. Elizabeth Delasobera and Tress Goodwin
Bradycardia Basics 433
Bradycardia Rhythms 433
Rhythms That Can Be Slow 434
Slow Atrial Fibrillation 435
Slow Atrial Flutter 437
AV Blocks 437
First-Degree AV Block 438
Second-Degree AV Block: Mobitz Type 1 (Wenckebach) 438
Second-Degree AV Block: Mobitz Type 2 438
Third-Degree or Complete Heart Block 439
Conclusion 439
6 Rhythms Presenting with Normal Rate 441
Robert Katzer and Janet Smereck
Definitions and Clinical Considerations 441
Regular Rhythms 441
Irregular Rhythms 442
References 447
7 Narrow Complex Tachycardia 449
David J. Carlberg and Rahul Bhat
Introduction 449
Mechanisms for NCTs 449
Approach to NCT 450
Sinus Node Tachycardias 453
Atrial Tachycardias 453
Reentrant Tachycardia Involving the AV Node 457
Junctional Tachycardia 459
Conclusions 459
References 460
8 Wide Complex Tachycardia 461
Scott Young and Rachel Villacorta Lyew
Introduction to Wide Complex Tachycardia 461
Monomorphic WCT 461
Polymorphic WCTs 468
References 470
Index 473
