Prosthetic implant of the type comprising: a tubular support (12) of axis X, which can be deformed between a compressed state with a small diameter and a dilated state with a larger diameter, the tubular support comprising a lattice comprising rhombus-shaped meshes (26), each mesh having a first diagonal (28) parallel to the axis X and a second diagonal (32) perpendicular to the axis X and at least one resilient membrane (14A, 14B) arranged inside the tubular support. The membrane comprises a fixing portion (48, 52), the fixing portion being fixed to a fixing section (65, 66) delimited by a strand (20A, 20B) of the tubular support, the fixing section being oriented substantially parallel to the axis X.