Fluoroscopy-free recrossing of the interatrial septum during left atrial ablation procedures.

AIM: The purpose of this is to evaluate the safety and feasibility of recrossing the interatrial septum in case of inadvertent loss of or need for repeated left atrial access using a simple electroanatomical landmark without the use of fluoroscopy.
METHODS: Twenty-five consecutive patients undergoing pulmonary vein isolation (PVI) for paroxysmal (n = 12) or persistent (n = 13) atrial fibrillation ablation were included. All procedures were performed using an electroanatomical mapping system (Carto 3, Biosense Webster, Diamond Bar, USA). After fluoroscopy-guided double transseptal puncture and fast anatomical mapping of the left atrium, a reconstruction of the transseptal access was created by retracting the mapping catheter into the sheath to the level of the inferior vena cava. After completing the left sided ablation, both sheaths and catheters were withdrawn to the inferior vena cava. Recrossing was then attempted by fellows (EF) and experienced operators (EO) using the reconstruction of the transseptal access in a standard right anterior oblique (RAO) and left anterior oblique (LAO) projection without the use of fluoroscopy.
RESULTS: Using the described technique, EP fellows and experienced operators could recross the interatrial septum without fluoroscopy in all patients. Median time needed for recrossing was 14 s (interquartile range (IQR) 7-20). Median recrossing times did not differ significantly between EF and EO (14 (IQR 8-26.5 s) versus 12 (IQR 6.5-17.5 s), p = 0.26). In five (20 %) procedures, recrossing was necessary during the procedure after intermittent mapping of the right atrium or inadvertent catheter dislodgment.
CONCLUSION: Adding a simple and fast anatomical reconstruction of the transseptal access to the standard left atrial mapping procedure allows for easy and fluoroscopy-free recrossing of the interatrial septum during atrial fibrillation ablation and further reduces radiation exposure.