ECG Study Guide Exam 1

P wave to beginning of QRS complex. Normal is 0.12 to .20 sec (3-4boxes)

End of PR Interval to end of S wave. Normal is .08 to .12 sec (2-3boxes) Ventricular Depolarization

Fist negative deflcetion. Abnormal if greater than 1 small box.Greater than 1/3 the amplitude of the QRS complex. Greater than 1/4th of R wave

Repolarization of ventricles.

Represents time of ventricular activity including both repolarization and depolarization. Measured from beginning of QRS complex to end of T wave. Normal is .36 to .44 (9-11 small boxes)

Begins at the end of S point and ends at the beginning of the T wave. Represents early part of vent repolarization

Contraction of the heart- blood is propelled into pulmonary artery; aorta

Phase of cardiac cycle atria and ventricles relax blood fills chambers

Force exerted by the blood on the walls of ventricles at the end of distole

Pressure or resistance against which the ventricles must pump to eject blood

Cardiac cells can not be stimulated to conduct an electrical impulse

Corresponds with the downslope of the T wave cardiac cells can be stimulated to depolarize if the stiumulus is strong enough

Movement of Ions across a cell membrane electrical event expected to result in a contraction

Less than 20 bpm dying heart

Dysrythmia originating in the Ventricle with a rate between 41 and 100