A treatment catheter system (2) for treatment of a heart valve (4) having a circumferential valve tissue structure (6), comprising an elongate catheter member (8) to be disposed at the interior of the circumferential valve tissue structure (6) and to be removed therefrom after treatment, wherein the catheter member (8) extends along a longitudinal axis (12) and has an inner lumen (14) and proximal (18) and distal (16) end portions, and wherein the catheter member (8) comprises a catching component (20) which is or can be positioned at the distal end portion (16) of the catheter member (8) to be non-separable from the catheter member (8) at least when being positioned at the distal end portion (16) of the catheter member (8) and which at least when being positioned at the distal end portion (16) of the catheter member (8) comprises a lateral groove (22) which extends transverse to the longitudinal axis (12) and which opens to a lateral outer side (24) to form a lateral catching opening (26), an elongate flexible outer member (28) to be disposed at the exterior (30) of the valve structure (6) at a level of the lateral groove (22), wherein the outer member (28) can at least partially extend circumferentially around the catheter member (8) with valve tissue of the circumferential valve tissue structure (6) being correspondingly circumferentially arranged between the catheter member (8) and the outer member (28), and a catching mechanism (32) operable to reduce a radial distance (D1) between the catheter member (8) and the outer member (32) to catch at least part of the valve tissue (6) between the outer member (28) and the catheter member (8) within the lateral groove (22) via the catching opening (26) to thereby immobilize and treat the caught valve tissue on the distal end portion (16) of the catheter member (6).La présente invention concerne un système de cathéter de traitement (2) pour le traitement dune valvule cardiaque (4) ayant une structure circonférentielle de
