ECG & EKG Julie, Kiley, Megan

The Electrocardiogram Also called EKG or ECG Electrical events of the heart travel through body ECG will reveal abnormal patterns of impulse conduction The appearance will differ due to the placement of monitoring electrodes The Electrocardiogram

Appearance Analyzing an ECG involves measuring the size of the voltage changes and determining the temporal relationships of the various components P wave- accompanies the depolarization of the atria QRS complex- appears as the ventricles depolarize. This signal is relatively strong because of the mass of the ventricular muscle An increase in heart size would increase the size of the complex T wave- indicates the ventricular repolarization

Times between waves are reported as segments and intervals Segments extend from the end of one wave to the start of another Intervals always include at least one entire wave Waves and Segments

P-R interval- extends from the start of atrial depolarization to the start of the QRS complex. Extension of the P-R interval to more than 200 msec can indicate damage to the AV node Q-T interval- indicates the time required for the ventricles to undergo a single cycle of depolarization and repolarization A congenital heart defect can cause sudden death without warning may be detectible as a prolonged Q-T interval Waves and Segments 2.0