Arrhythmias and Clinical EP

A429JACC March 17, 2015Volume 65, Issue 10S

ElECtrophysiologiCal obsErVations during lEft atrial sEptal linEar ablation: Validation of bidirECtional ConduCtion bloCk

Poster ContributionsPoster Hall B1Sunday, March 15, 2015, 3:45 p.m.-4:30 p.m.

Session Title: Ablation for Atrial Fibrillation and It’s Many FacesAbstract Category: 4. Arrhythmias and Clinical EP: AF/SVTPresentation Number: 1219-254

Authors: Pugazhendhi Vijayaraman, Gopi Dandamudi, Kenneth Ellenbogen, Geisinger Heart Institute, Wilkes-Barre, PA, USA, Virginia Commonwealth University Health Center, Richmond, VA, USAbackground: Mitral isthmus (MI) flutters are common macro reentrant atrial tachycardias (MRAT). Ablation of MI is challenging, requires high power (40-50 W) and ablation in the coronary sinus (CS) with low success rates. We describe a novel left atrial septal linear (LASL) ablation.Methods and results: LASL ablation was performed in 8 pts ( Male 50%, Age 68±8 yrs, prior ablation 75%) undergoing ablation for atrial fibrillation (AF) and/or MRAT. Ablation was performed during MI flutter in 6 pts and septal MRAT in 2 pts. Lateral MI ablation was unsuccessful in 5 pts. Ablation was performed from septal mitral annulus (10 O’ clock) to RSPV (30W). Significant prolongation of tachycardia cycle length (TCL) from 340 ± 97 ms to 456 ± 153 ms was noted before termination in all pts. Fluroscopy and ablation duration were 4 ± 2 minutes and 12 ± 5 minutes. Bidirectional conduction block (BDB) was confirmed in all pts by pacing both sides of the line (conduction time 266 ± 96 ms, Range 170-400 ms) and differential pacing. Pacing lateral to the line resulted in reversal of activation from ant LA-CSd-CSp->septal LA. RA to LA appendage (LAA) time was long at 210±65 ms in sinus rhythm. One pt developed LAA isolation. At mean f/u of 16 ± 5 months, 1 pt developed AT.Conclusion: LASL ablation was easier to perform, safe and successful (8 of 8) in achieving BDB without complications. Significant prolongation of TCL (116±56 ms) was noted prior to termination of flutter. Significant RA-LA conduction delay was noted post ablation.