BIOC63H3 Lecture Notes - Lecture 6: Pr Interval, Qrs Complex, Qt Interval
Document Summary
Electrical impulses originating in the sa node produce various waves on the ecg as they spread throughout the heart. The first wave in the cardiac cycle is known as the p wave, which represents depolarization of the right and left atria prior to their contraction. The beginning of the p wave is recognized as the first abrupt or gradual deviation from the baseline and its end is the point at which the waveform returns to the baseline. The pr segment is part of the pr interval and is that area noted from the end of the p wave to the beginning of the qrs complex. It represents atrial depolarization and conduction through the. There is a delay in conduction through the av node, allowing time for the contents of the atria to empty into the ventricles before ventricular contraction begins. The impulse then spreads to the bundle of his, bundle branches, and purkinje fibers.
