The invention relates to a catheter, provided with an elongated body with an electrically conductive first end, wherein through said body at least one live wire extends which is connected to said first end and a channel for feeding a cooling fluid through said body, which channel is provided, in or near said first end, with at least one outlet opening and wherein, in said first end, a temperature sensor has been arranged, while said channel is thermally insulated from said first end.Linvention concerne un cathéter doté dun corps allongé avec une première extrémité électroconductrice, dans lequel sétend au moins un fil sous tension traversant ledit corps, qui est relié à la première extrémité et un canal dalimentation en fluide de refroidissement traversant ledit corps. Ce canal comporte, dans la première extrémité, ou à proximité de celle-ci, au moins une extrémité de sortie. Un capteur de température est disposé dans la première extrémité, et ledit canal est thermiquement isolé de la première extrémité.The invention relates to a catheter, provided with an elongated body with an electrically conductive first end, wherein through said body at least one live wire extends which is connected to said first end and a channel for feeding a cooling fluid through said body, which channel is provided, in or near said first end, with at least one outlet opening and wherein, in said first end, a temperature sensor has been arranged, while said channel is thermally insulated from said first end.