Skip to main content
. Author manuscript; available in PMC: 2013 Apr 1.
Published in final edited form as: Circ Arrhythm Electrophysiol. 2012 Mar 9;5(2):371–379. doi: 10.1161/CIRCEP.111.969493

Figure 2.

Figure 2

Effect of pacing at various cycle lengths on phase 4 depolarization in 2 superior vena cava (SVC) sleeve preparations. A: The upper panel displays action potentials (APs) elicited at basic cycle lengths (BCLs) of 1000 to 100 ms followed by pauses. The lower panel is an expanded view of the same sequence of APs. B: The upper panel displays APs elicited at BCLs of 300 to 100 ms followed by pacing at BCL of 2000 ms. The lower panel is an expanded view of the same sequence of APs. In both SVC preparations, faster pacing induces marked hyperpolarization and a steeper phase 4.