Stent delivering system and back releasing assembly thereof

Abstract

The inversion provides a stent delivering system and a back releasing assembly thereof. Constraint of a near end of a stent is achieved through a plurality of back releasing rods; during installation, the near end of the stent is hanged on all the back releasing rods, the back releasing rods are pushed into fixing holes of a conical head through a back releasing back end so as to constrain the near end of the stent; during releasing of the near end of the stent, a back releasing guide wire is pulled to drive the back releasing back end and the back releasing rods fixed on the back releasing back end to move axially, and then the back releasing rods depart from the fixing holes of the conical head, the near end of the stent is disengaged with the back releasing rods, and the near end of the stent is released. The back releasing assembly can effectively constrain the near end of the stent through a back releasing fixing member of the back releasing assembly; the reliability of axial movement of the back releasing rods can be improved; resistance is less during releasing due to small contact areas between the back releasing rods and the fixing holes; and the accuracy of the whole releasing process can be improved.

Description

technical field [0001] The invention relates to the field of medical operation equipment design, in particular to a stent delivery system and a post-release assembly. Background technique [0002] A stent graft is an implantable device consisting of a tubular surgical graft sheath and a self-expanding frame. The covered stent is placed in the blood vessel, which can block the aneurysm and rebuild the blood flow path, so that the hemodynamic pressure cannot reach the vascular lesion. [0003] When the stent graft is released in the segment of the blood vessel that needs to be repaired, it needs the cooperation of the delivery system. During the implantation of the covered stent, due to the impact of the blood flow, the covered stent often shifts and folds, so it is particularly critical to accurately locate the position of the covered stent. Therefore, during the operation, it is necessary to release the stent body of the stent-graft first, restrain the bare stent section a...

AI Technical Summary

Problems solved by technology

[0005] 1. The stent-graft without a post-release system, that is, the stent-graft is released directly, and the stent-graft is released by the retraction of the outer tube. The disadvantage is that the released stent-graft will migrate under the action of blood flow and impact. resulting in inaccurate final stent graft position;

[0006] 2. For the banded stent graft, the banded stent graft is also released by withdrawing the outer tube, and the binding wire is untied by controlling the twitch of the guide wire to release the stent graft. The disadvantage is that the stent graft may be shortened. Shrinkage causes displacement of the covered stent;

The disadvantage of this structure is that: when the bare section of the bracket is installed on the fixing groove, it is unstable, which causes inconvenience to the installation of the fixing pin; the cross section of the fixing pin is rectangular, and the resistance when installing and releasing is large; The control mechanism of the pin is that the movement of the coaxial tube drives the movement of the fixed pin. This movement mechanism involves the friction of the coaxial tube. The friction area is large and the release resistance is large.

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