fig4

Figure 4. Transseptal puncture under fluoroscopic (A) and TEE (B) guidance. A puncture 4 to 4.5 cm above the MV plane in a posterosuperior position allows good maneuverability of the delivery system. After the transseptal puncture, a guidewire is introduced in the left atrium and then in the left superior pulmonary vein (C)