LAUSR

### Learning objectives To learn how to: Transseptal catheterisation was introduced in the late 50s1 and gained popularity with the introduction of the electrophysiological and structural heart interventions.2–10 Here, we shall describe the use of transseptal puncture (TSP) technique in the main transcatheter structural, and especially valve, interventions. ### Indications In current practice, the use of TSP has shifted from a diagnostic procedure, which is now used only exceptionally, to the first step before percutaneous interventions. Transseptal puncture has been used worldwide for percutaneous mitral commissurotomy (PMC). More recently, it is increasingly performed for transcatheter interventions on the mitral valve (MitraClip procedure, annuloplasty or valve implantation: valve in valve, valve in a ring, valve in massive annular calcification), left atrial appendage closure and paravalvular leak closure. Finally, very recently it was also used for the new techniques of transcatheter mitral valve implantation.6 7 Its use for percutaneous aortic valve intervention has been almost entirely abandoned.10 ### Contraindications The main contraindications to be excluded before TSP are as follows: The other following contraindications are relative: If the patient receives vitamin K blockers, there is …