A treatment catheter system for treatment of a heart valve includes a circumferential valve tissue structure and an elongate catheter member, and has an inner lumen, proximal and distal end portions. The system includes a catching component which can be positioned at the distal end portion of the catheter member to be non-separable from the catheter member. An outer member extends circumferentially around the catheter member. The circumferential valve tissue structure is correspondingly arranged between the catheter member and the outer member. A catching mechanism reduces a radial distance between the catheter member and the outer member to catch the valve tissue between the outer member and the catheter member via a catching opening to immobilize and treat the caught valve tissue on the distal end portion of the catheter member.
