PowerPoint Presentation

ABCs of ECGsBasic ECG Analysis and Interpretation Skills

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What is an ECG?

An ECG (electrocardiogram) is a tracing of the electrical impulses as they travel through the heart.

Why Do We Perform ECGs?Documenting type of arrhythmia a patient may haveBaseline for evaluating cardiac size and rhythm characteristicsAnesthetic monitoringPre and Post surgical monitoringMonitoring a patients response to antiarrhythmic therapy

Questions to Ask Yourself When Evaluating an ECGIs the heart rate and rhythm normal Are all the complexes similar in appearance Is there a P wave present for each QRS complexIs there a QRS for each P waveIs the ECG tracing free from artifacts and have a clean baseline

Conduction System

Lead Placement

Lead I RA and LA

Lead II RA and LL

Lead III LA and LL

Movement Artifact

Poor Contact

Heart Rate CalculationPaper speed set at 50mm/secCount number of complexes in a 3 second time frame and multiply by 20Count number of small boxes from one R wave to the next consecutive R wave and divide into 3000Paper speed set at 25mm/secCount number of complexes in a 6 second time frame and multiply by 10Count number of small boxes from one R wave to the next consecutive R wave and divide into 1500

Ventricular Premature BeatsPremature beats that arise within the ventricle Can be caused from cardiac or systemic disease, splenic tumors, post surgical procedures such GDV and splenectomy Stress and excitement may cause increase in frequency

Usually have a wide bizarre pattern to the QRS complexP waves may or may not be visibleCan have a negative or positive deflectionMay occur as single beat, couplet, triplet, or sustained run

Couplet vs. Triplet

Couplet

Triplet

Ventricular Tachycardia

Ventricular arrhythmia that has more than 3 VPCs in a rowMedical intervention is appropriate for rates >160beats/minLidocaine is drug of choice to terminate rhythmPatients with runs of V-Tach may experience episodes of syncope or sudden death

Ventricular Escape Rhythm

Idioventricular rhythm

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Atrial Premature BeatsPremature beats that arise above the ventricle with in the atria Can be caused from progression of cardiac disease with increased atrial size, inflammatory and systemic disease, tumors and cancer that involve atrial tissue Stress and excitement may cause increase in frequency

Usually they have a similar appearance to other QRS complexes, just happen at an earlier intervalP waves may or may not be visibleP waves can have a negative or positive deflectionMay occur as single beat, couplet, triplet, or sustained run

Atrial Bigeminy

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Supraventricular Tachycardia

Runs of atrial tachycardia either intermittent or sustained Usually sustained SVT occurs at high heart rates and should be encouraged to break with IV drugs Sustained SVT can cause the heart muscle to become weak and mimic DCM but effects can be reversed with arrhythmia control

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Supraventricular Tachycardia

Starts and stops abruptly 26

SVT vs. Sinus TachycardiaSVT (supraventricular tachycardia)

Sinus Tachycardia

Atrial Fibrillation

Classified as an irregularly irregular rhythmHigh ventricular rate of supraventricular originNo P waves presentLone primary atrial fibrillation or can be secondary to structural heart diseaseGoal is to get patients heart rate