A catheter (4) comprising a connector (8) with a guide wire channel (12) and an inflation channel (16), a shaft (20) extending from a proximal end (24) to a distal end (28) and having a guide wire lumen (32) and an inflation lumen (36), the shaft (20) being connected, at its proximal end (24), to the connector (8) so that said guidewire lumen (32) and inflation lumen (36) are mechanically and fluidically connected with said guide wire channel (12) and inflation channel (16) respectively. The connection is realised in correspondence of a kink portion (44). The catheter (4) comprises a protective sheath (52) placed around an external wall (56) of the shaft (20) and extending from a first sheath end (60), axially placed at a first distance (L1) from the proximal end (24) of the shaft (20) so as to allow a direct contact and a fixing between the external wall (56) of the shaft (20) and the internal wall (64) of the kink portion (44), to a second sheath end (68), axially extending at least in correspondence of a second kink end (42) of the kink portion (44), so as to avoid a direct contact and a fixing between the external wall (56) of the shaft (20) and the internal wall (64) of the kink portion (44).Linvention concerne une sonde (4) comprenant un raccord (8) doté dun conduit (12) pour fil de guidage et dun conduit (16) de gonflage, une tige (20) sétendant dune extrémité proximale (24) à une extrémité distale (28) et comprenant une lumière (32) pour fil de guidage et une lumière (36) de gonflage, la tige (20) étant reliée, à son extrémité proximale (24), au raccord (8) de telle façon que ladite lumière (32) pour fil de guidage et ladite lumière (36) de gonflage soient reliées mécaniquement et fluidiquement audit conduit (12) pour fil de guidage et audit conduit (16) de gonflage, respectivement. Le raccordement est réalisé de façon à correspondre à une partie (44) de pliure. La sonde (4) comporte une gaine protectrice (52) placée autour dune paroi extérieure (56) de la t