Figure 4.
AOD from CS 1-2 advanced the tachycardia with an A-H-A response. AOD was delivered just after the slow pathway refractory so that it anterogradely captured and advanced the tachycardia via the slow pathway. Note that the PPI at the proximal CS electrograms (CS 9,10) as a proxy for septal activation had a PPI-TCL of 30 or 40 ms depending on how one measures the TCL. This value confirmed that the atrial septum near the tricuspid annulus was part of the reentrant circuit.