Figure legend
Fig 1: A: Induction of typical AVNRT (tachy1, with APD). B: successful entrainment with VOP and long cPPI-TCL and StimA- VA.
Fig 2A: After initial slow pathway modification for tachy1, this one and half beat of long VA (septal VA 164 ms) echo was noted reproducibly at baseline.
2B: With isoprenaline, sustained tachy2 was induced with long VA ( VA= 144 ms) similar to the above-mentioned echo beat.
2C: One of the attempted VOP. During initial few beats the tachy2 (AA= 340 ms) continued at its own rate (TCL=340ms) as seen in first 2 beats in Fig 2C. In the 8th beat of the drive train (3rd beat in fig 2C) of VOP @320 ms, the AA interval suddenly prolongs by 23ms as compare to TCL (340 ms), suggesting termination of the tachy2. After termination AA interval was same as RV pacing CL @320 ms. Noted the change in CS78-CS56 A-EGM relation during tachycardia (first 2 beats) and VA conduction (last 2 beats). The polarity reversal was noted in A – EGM of CS 78.
(TCL- tachycardia cycle length, CL- cycle length)
CS- coronary sinus catheter, CS78- proximal CS, CS 12- distal CS, His D- His catheter distal pole, His P- His catheter proximal pole, Map – Mapping catheter in right ventricle, STIM- Stimulation.)