ECG : An Introductory Course A Practical Introduction to Clinical Electrocardiography

Since 1955, we have conducted an annual one-week ECG course at Innsbruck. This book represents a summary of our didactic experience. This English translation follows the enlarged sixth German edition. It contains many diagrams and new examples of tracings, such as the orthogonal leads system of Frank, explanation of extreme axis devia­ tion by the hemiblock concept, atrioventricular conduction disorders (His bundle electrogram), re-entry mechanisms, and the exercise ECG. The limits and dangers of ECG interpretations that, in our opinion, should be emphasized in an introductory presentation, are summarized in a final chapter. Our main aim was to make indigestible material palatable to the beginner; to provide him with a red thread through the labyrinth of ECG patterns by adopting a uniform approach, namely vectorial interpretation, in order to understand especially difficult areas (e. g. the differential diagnosis of infarction) by means of simplified diagrams; and to prepare him for the study of systematic textbooks. We believe that many such books should be read in order to comprehend a subject that is generally considered difficult by physicians and at the same time to promote critical understanding when called upon to evaluate an ECG in practice. The following publications to which we ourselves owe valuable suggestions, even if they are not explicitly mentioned in our text, are recommended: BELZ, G. G., STAUCH, M.: Notfall-EKG-Fibel, 2nd ed. Berlin, Heidel­ berg, New York: Springer 1977 BUCHNER, C. H., DRAGERT, W.: Schrittmachertherapie des Herzens.

1. Vectorcardiography.- 2. Usual ECG Leads and Their Interrelation.- 3. Interpretation of the “Electric” Axis of the Heart.- 4. The Normal ECG.- 4.1 The P Wave.- 4.2 The AV Interval (PQ or PR).- 4.3 The QRS Complex.- 4.3.1 QRS Amplitude.- 4.3.2 QRS Duration.- 4.3.3 QR Interval (Intrinsicoid Deflection).- 4.4 The ST-T Segment.- 4.5 The T Wave.- 4.6 The QT Interval.- 4.7 The U Wave.- 5. Memory Aid to Systematic ECG Description and Evaluation.- 6. Ventricular Conduction Disorder ― Bundle Branch Block.- 6.1 Unifascicular Block.- 6.1.1 Right Bundle Branch Block (RBBB).- 6.1.1.1 Wilson Block.- 6.1.1.2 “Classic” Right Bundle Branch Block with right axis deviation.- 6.1.1.3 “Classic” Right Bundle Branch Block with sagittal axis deviation.- 6.1.1.4 Incomplete Right Bundle Branch Block.- 6.1.2 Left Anterior Hemiblock (LAH).- 6.1.3 Left Posterior Hemiblock (LPH).- 6.2 Bifascicular Bundle Branch Block.- 6.2.1 Left Bundle Branch Block (LBBB).- 6.2.2 Left Anterior Hemiblock and Right Bundle Branch Block.- 6.2.3 Left Posterior Hemiblock and Right Bundle Branch Block.- 6.3 Trifascicular Blocks.- 7. The WPW Syndrome.- 8. ECG in Hypertrophy of Individual Chambers of the Heart.- 8.1 ECG in Hypertrophy of the Atria.- 8.2 ECG in Hypertrophy of the Ventricles.- 8.2.1 Depolarization.- 8.2.2 Repolarization.- 8.2.3 Position of the Cardiac Axis.- 9. ECG in Myocardial Infarction.- 9.1 Hypotheses of Necrosis, Injury, Ischemia.- 9.1.1 ECG in Necrosis (Q in Infarction).- 9.1.2 ECG in Injury (Changes in Outer Layers ― ST Elevation).- 9.1.3 ECG in Local Ischemia (Negative Terminal T)…..- 9.1.4 ECG in Acute Hypoxia (“Asphyxia T”).- 9.1.5 ECG in Chronic Coronary Insufficiency (Subendocardial Injury).- 9.2 Sites of Myocardial Infarction.- 9.2.1 Extensive Anterior Infarct.- 9.2.2 Anteroseptal Infarct.- 9.2.3 Anterolateral Infarct.- 9.2.4 Lateral Infarct.- 9.2.5 Posterior Wall Infarct.- 9.2.6 Posteroseptal Infarct.- 9.2.7 Posterolateral Infarct.- 9.2.8 Multiple Infarcts.- 9.2.9 Apical Infarct.- 9.2.10 Posteroinferior Infarct.- 9.2.11 High Infarcts.- 9.2.12 Subendocardial Infarct (Inner Layer Infarct).- 9.3 Course and Classification of Infarcts.- 9.4 Differential Diagnosis of the ECG in Myocardial Infarction.- 9.4.1 Differential Diagnosis of QRS Changes Suspected to be Due to Infarction.- 9.4.1.1 Differential Diagnosis of Posterior Wall Infarct.- 9.4.1.2 Differential Diagnosis of Anterior Wall Infarct.- 9.4.2 Differential Diagnosis of Infarct-Suggestive ST Elevation.- 9.4.3 Differential Diagnosis of Infarct-Suggestive (Terminal Negative) T.- 9.5 Infarct and Bundle Branch Block.- 10. Changes in the ST-T Segment.- 10.1 Causes of ST-T Changes.- 10.1.1 Primary ST-T Changes of Cardiac Origin.- 10.1.1.1 Absolute or Relative Coronary Insufficiency in Degenerative Heart Disease.- 10.1.1.2 Imflammatory Heart Disease.- 10.1.2 Primary ST-T Changes of Extracardiac Origin.- 10.1.2.1 Autonomic Nervous System Disorders.- 10.1.2.2 Electrolyte Disturbance.- 10.1.2.3 Digitalis.- 10.1.2.4 Simulated ST Depression.- 11. Exercise ECG.- 11.1 Changes in the Exercise ECG Suggestive of Coronary Disease.- 11.2 Doubtful and Prognostically Unreliable Changes in the Exercise ECG.- 11.3 Absolute Contraindications to the Exercise Tolerance Test or Bicycle Dynamometry.- 11.4 Relative Contraindications.- 11.5 Criteria for Discontinuance.- 12. ECG Diagnosis of Arrhythmias.- 12.1 Are (normal) P Waves Present?.- 12.2 What is the Distance Between Individual P Waves?.- 12.3 What is the Shape of the P waves?.- 12.4 What is the Distance of P Waves from the Following QRS Complex?.- 12.5 What is the Distance Between Apparently Identical Ventricular Complexes?.- 12.6 What is the Time Relation of Differently Shaped Ventricular Complexes to Each Other or to the Basic Rhythm?.- 12.6.1 Extrasystoles.- 12.6.2 Escape Beats.- 12.6.3 Escape Rhythms.- 12.6.4 Parasystoles (Para-arrhythmia).- 12.7 Incidence of Different Types of Arrhythmia.- 13. Pacemaker ECG.- 13.1 Fixed-Rate Pacemakers.- 13.2 Demand Pacemakers.- 13.2.1 R-Wave Inhibited.- 13.2.2 R-Wave Triggered.- 13.3 Atrial-Triggered Pacemakers.- 13.4 Bifocal Demand Pacemakers.- 13.5 Complications After Pacemaker Implantation.- 13.5.1 Complete Failure of Pacemaker Impulses.- 13.5.2 Normal Pacemaker Impulses Without Stimulus Response.- 13.5.3 Racing Pacemaker.- 14. ECG in Children.- 14.1 Normal Development of ECG as a Whole.- 14.1.1 Newborns.- 14.1.2 Infants.- 14.1.3 Young children.- 14.1.4 School-Aged Children.- 14.2 Characteristic Patterns of Childhood Tracings.- 14.3 Effects of Extracardiac Factors.- 14.4 Technical Difficulties.- 15. Technique of ECG Recording.- 16. Concluding Cautionary Remarks on ECG Interpretation.- 16.1 Cardiac Arrhythmias.- 16.2 Diagnosis of Infarction.- 16.3 Suspected Hypertrophy of Individual Parts of the Heart.