Data regarding transseptal catheterization in the Centers involved will be retrospectively collected over the past 10 years.~Will be collected:~1) patients characteristics~type of procedure requiring transseptal catheterization~success rate~adverse events~use of tools for transseptal catheterization:~intracardiac echocardiography (ICE) guidance~simplified transseptal puncture~pig tail catheter~safe sept guidewire~powered radiofrequency transseptal needle
The goal of this observational study is to learn about the changing over the time of transseptal (TSP) catheterization for catheter ablation of arrhythmias in the left heart. This study aims to investigate if auxiliary tools for TSP catheterization improved the safety and efficacy.