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 bookECGs 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.

William J. Brady, MD, is Professor of Emergency Medicine and Medicine, University of Virginia, Charlottesville, VA, USA.

Michael J. Lipinski, MD, PhD, is Cardiovascular Associates of Charlottesville, Charlottesville, VA, USA.

Andrew E. Darby, MD, FHRS, is Associate Professor of Cardiovascular Medicine, University of Virginia Health System, Charlottesville, VA, USA.

Michael C. Bond, MD, FACEP, FAAEM, is Associate Professor of Emergency Medicine, University of Maryland School of Medicine, Baltimore, MD, USA.

Nathan P. Charlton, MD, is Associate Professor of Emergency Medicine, Division of Medical Toxicology, University of Virginia, Charlottesville, VA, USA.

Korin Hudson, MD, is Associate Professor of Emergency Medicine, MedStar Georgetown University Hospital, Georgetown University School of Medicine, Washington, DC, USA.

Kelly Williamson, MD, is Assistant Residency Program Director, Advocate Christ Medical Center Emergency Medicine Residency; and is Clinical Associate Professor of Emergency Medicine, University of Illinois at Chicago, Chicago, IL, USA.

List of Contributors xxi

Section I The ECG in Clinical Practice1

1 The ECG in Clinical Medicine3
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 Electrocardiogram13
Trale Permar and Kelly Williamson

References 17

Section II ECG Changes in Myocardial Ischemia19

1 The Cardiac Action Potential and Changes in the Setting of Acute Coronary Syndrome: How Ischemia and Infarction Impacts the ECG21
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 Myocardium37
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 Mimics53
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 STElevation 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 Syndromes75
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 Monitoring97
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 Testing107
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 ECG123

1 Bradycardia125
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) Block133
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 Block141
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 Tachycardia149
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 Tachycardia161
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 Rates169
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 Arrest173
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 Complexes181
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 Conditions187
Andrew E. Darby

Introduction 187

Antiarrhythmic Drug Toxicity 188

Tricyclic Antidepressant Toxicity 190

Conclusions 191

References 192

10 Dysrhythmia-Related Syndromes193
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 Scenarios201

1 The Patient with Cardiac Arrest203
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 Pain207
Paul Basel, Lane Thaut, and Nathan Olson

Introduction 207

Acute Coronary Syndrome 207

Pericarditis 213

References 215

3 The Patient with Dyspnea219
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/Syncope229
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 Evaluation239
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 Shock249
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 Overdose265
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 Emergencies275

1 ECG Diagnosis and Management of the Poisoned Patient277
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 Strategy287
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 Abnormalities297
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 Abnormalities307
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 Emergencies315
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 Groups327

1 The ECG-Monitored Patient329
Feras Khan

Introduction 329

Clinical Scenarios Requiring Telemetry/Electrocardiographic Monitoring 329

Conclusion 332

References 334

2 Electrocardiography in the Operating Room335
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 Unit345
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 Devices359
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 Transplantation377
Semhar Tewelde

Introduction 377

Cardiac Transplantation 377

Conclusion 80

Key Points 380

References 380

Section VII Electrocardiographic Differential Diagnosis383

1 Abnormalities of the P Wave and PR Interval385
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 Abnormalities397
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 Changes407
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 Abnormalities421
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 Bradycardia433
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 Rate441
Robert Katzer and Janet Smereck

Definitions and Clinical Considerations 441

Regular Rhythms 441

Irregular Rhythms 442

References 447

7 Narrow Complex Tachycardia449
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 Tachycardia461
Scott Young and Rachel Villacorta Lyew

Introduction to Wide Complex Tachycardia 461

Monomorphic WCT 461

Polymorphic WCTs 468

References 470

Index 473