Peter Spector, M.D.; Nicole Habel, M.D. iii Shorthand convention meaning "advances the timing of the subsequent atrial activation." iv Delivered during His refractoriness v The conclusions that we are ...

In tracing "a" of Figure 1, there seems to be only one P wave in front of each QRS complex, suggesting sinus rhythm. However, during the compensatory pauses after the PVCs (↑) in tracing "b," there ...