Introduction: Transseptal puncture is currently used in various procedures performed at the level of left atrium: Mitraclip insertion, left auricullum closure, or pulmonary vein electrical isolation.

Objective: The purpose of this study was to compare the transesophageal ultrasound with intracardiac ultra-sound to guide transseptal puncture.

Methods: Of the total number of patients who un-derwent atrial fibrillation ablation we selected only those in which we used intracardiac echography or transesophageal echography to guide transseptal punc-ture. The septum was viewed in its lower and posterior portions.

Results: In 29 patients the transeptal guiding was per-formed using intracardiac ultrasound and in 7 by tran-sesophageal echography. Of the 29, in 26 patients we were able to advance with the ICE probe in the middle of the right atrium due to the particular venous ana-tomy. For the ICE group, local anesthesia was used with Xiline and for the ETE group deep sedation and gene-ral anesthesia with orotracheal intubation. Interatrial septal visualization was performed with the ICE pro-be located in the middle of the atrium bended towards the lateral wall in the 26 patients. For the ETE group we used the bicaval incidence and the short axis 30-60 degrees for the 7 patients. The posterior and inferior side of the septum were better visible using ICE. One patient in the ICE group developed pericardial effusion during the procedure.

Conclusions: Intracardiac ultrasound is superior to transesophageal ultrasound for interatrial septum vi-sualization in the posterior and inferior region. Intra-cardiac probe placement was possible in only 89% of patients. Transesophageal ultrasound requires general anesthesia and orotracheal intubation.