Advanced 12 Lead ECG Interpretation

Course overview

Objectives Explain ECG arrhythmia identification Discuss complex issues twelve lead ECGs can help providers identify in the field Describe cardiac anatomy and physiology Content 1 Lead systems and heart surfaces 1 ECG rhythm analysis 1 Value 2 Limitations 2 Heart surfaces 1 Inferior 2 Left lateral 3 Precordial 1 Acute signs of ischemia injury and necrosis possible early identification of patients with acute myocardial infarction for intervention thrombolysis PTCA 2 The role of out of hospital twelve lead ECG is not universally available but is appropriate in most EMS settings with proper medical oversight 4 Advantages and disadvantages 5 ST segment elevation 1 Height depth and contour 2 ST acute changes 1 Anterior wall significant ST elevation in V1 V4 may indicate anterior involvement 2 Inferior wall significant ST elevation in II III and aVF may indicate inferior involvement 3 ST segment depression in eight or more leads 4 ST segment elevation in aVR and V1 6 Q waves 1 Depth duration and significance 1 Greater than five millimeters greater than zero point zero four seconds 2 May indicate necrosis 3 May indicate extensive transient ischemia 2 Cardiac arrhythmias 1 Approach to analysis 1 P wave 1 Configuration 2 Duration 3 Atrial rate and rhythm 2 PR interval 3 QRS complex 1 Configuration 2 Duration 3 Ventricular rate and rhythm 4 ST segment 1 Contour 2 Elevation 3 Depression 5 QT interval 1 Duration 2 Implication of prolongation Relationship of P waves to QRS complexes 1 Consistent 2 Progressive prolongation 3 No relationship 7 T waves 8 U waves 2 Interpretation of the ECG 1 Origin of complex 2 Rate 3 Rhythm 4 Clinical significance Arrhythmias originating in the sinus node 1 Sinus bradycardia 2 Sinus tachycardia 3 Sinus arrhythmia 4 Sinus arrest Arrhythmias originating in the atria 1 Premature atrial complex 2 Atrial ectopic tachycardia 3 Re entrant tachycardia 4 Multifocal atrial tachycardia 5 Atrial flutter 6 Atrial fibrillation 7 Atrial flutter or atrial fibrillation with junctional rhythm 8 Atrial flutter or atrial fibrillation with pre excitation syndromes Arrhythmias originating within the AV junction 1 First degree AV block 2 Second degree AV block 1 Type one Wenkebach 2 Type two infranodal classical 3 Complete AV block third degree block Arrhythmias sustained or originating in the AV junction 1 AV nodal re entrant tachycardia 2 AV reciprocating tachycardia 1 Narrow 2 Wide 3 Junctional escape rhythm 4 Premature junctional complex 5 Accelerated junctional rhythm 6 Junctional tachycardia Arrhythmias originating in the ventricles 1 Idioventricular rhythm 2 Accelerated idioventricular rhythm 3 Premature ventricular complex ventricular ectopic 1 R on T phenomenon 2 Paired couplets 3 Multiformed 4 Frequent uniform 4 Rule of bigeminy pertaining to precipitating ventricular arrhythmias 5 Ventricular tachycardia 1 Monomorphic and polymorphic 1 Ventricular fibrillation 2 Ventricular standstill 3 Asystole 4 Abnormalities originating within the bundle branch system 1 Incomplete or complete 2 Right bundle branch block 3 Left bundle branch block 5 Differentiation of wide QRS complex tachycardia 1 Potential causes 1 Supraventricular tachycardia with bundle branch block 2 Accessory pathways 2 Differentiation 1 Physical evaluation 1 Cannon A waves 2 Vary intensity of first heart tone 3 Beat to beat changes in blood pressure 2 ECG differences 1 Aberration as a result of premature atrial complex 1 Identify PAC in previous ST segment or T wave 2 Sudden change in rate with bundle branch aberration 3 Concealed retrograde conduction 4 Right bundle branch refractoriness may be time dependent 5 Compare with previous ECG when available 2 RBBB aberration V1 positive 1 Biphasic lead one with a broad terminal S wave 2 Triphasic QRS in V4 3 LBBB aberration V1 negative 1 Monophasic notched lead one 2 Slurred notched or RSr in lead V4 V5 or V6 4 Concordant precordial pattern