CN209220581U - Double layer covered stent - Google Patents

Abstract

The utility model discloses a kind of double-deck overlay film frames, for the tubular structure for being fitted tightly over blood vessel wall inner side, including supporting structure and overlay on the biomembrane on supporting structure, the supporting structure includes inner metallic layer bracket and the metal outer bracket that is set in outside inner metallic layer bracket, and the biomembrane overlays between outer stent and inner stent.The utility model uses the double-layer bracket structure of outer stent and inner stent, and biomembrane is overlayed between outer stent and inner stent, form solid supporting structure, it is unlikely to deform supporting structure, overlay film breach caused by supporting structure deforms is reduced and bracket punctures the intravascular leakage of overlay film formation.

Description

Double layer covered stent

technical field

The utility model relates to the technical field of medical devices, in particular to a double-layer film-covered stent.

Background technique

Stent implantation refers to a technology that uses techniques such as puncture, catheter, balloon catheter expansion and metal stent placement to expand and recanalize narrowed or occluded blood vessels or lumens, and solve traditional surgical blind spots.

Stenosis and occlusion of blood vessels and lumens are the treatment strengths of interventional stent implantation technology. It has the advantages of small trauma, high curative effect, low risk, few complications, and short hospital stay, creating a new way for narrowing and occlusion of blood vessels and lumens. It is the development direction of surgery to obtain the same or even higher curative effect with as little trauma as possible. The successful clinical application of laparoscopy and coronary angioplasty is a typical example.

Covered stents refer to artificial internal grafts in which the inner or outer surfaces of bare metal stents are partially or completely covered with membranous materials. The covered stent not only retains the supporting function of the common stent, but also can effectively improve the abnormal hemodynamics of the diseased blood vessel, so it has been widely used in the treatment of peripheral vascular malformation lesions and acute and chronic vascular injuries and other vascular diseases.

At present, covered stents are generally divided into straight tube type and bifurcated type, and the stent structure is usually a single-layer stent structure, and a covering is added to part or all of the stent structure. When part of the stent structure is covered with a membrane, part of the stent structure is a bare stent, and the bare stent cannot isolate the blood flow, and cannot achieve hemostasis for dissection or blood vessel rupture; when the entire stent structure is covered with a membrane, the single-layer stent During the use of the structure, because the structure is not firm enough, it is easy to cause a membrane crack due to blood vessel deformation or the stent punctures the membrane to form a vascular endoleak.

Utility model content

Aiming at the prior art, the utility model provides a double-layer film-covered stent, which adopts a double-layer stent structure of an outer layer stent and an inner layer stent, and covers the biofilm between the outer layer stent and the inner layer stent to form a solid The stent structure makes the stent structure not easy to deform, and reduces the membrane gap caused by the deformation of the stent structure and the vascular endoleak caused by the stent piercing the membrane.

The utility model is realized through the following technical scheme: the double-layer covered stent is a tubular structure closely attached to the inner side of the blood vessel wall, including a stent structure and a biofilm covering the stent structure, and the stent structure includes a metal inner layer stent and a metal outer stent sheathed outside the metal inner stent, and the biofilm is covered between the outer stent and the inner stent.

The biofilm is covered between the outer metal stent and the inner metal stent and closely adheres to the inner surface of the outer metal stent and the outer surface of the inner metal stent, so that it is closely attached to the inner side of the blood vessel wall to achieve a good Hemostatic effect. The outer diameter of the double-layer stent-graft is slightly larger than the inner diameter of the blood vessel. After the double-layer stent-graft is implanted, the double-layer stent-graft adheres closely to the inner wall of the blood vessel to achieve the effect of hemostasis. Due to the supporting effect of the outer stent and the inner stent, the internal and external forces of the biofilm are uniform, so that the biofilm is not easily deformed, damaged, and ruptured, and the vascular endoleak formed by the membrane crack and the stent piercing the membrane is avoided.

Further, when the double-layer stent-graft is placed on the thoracic aorta where the proximal and distal vessel diameters gradually decrease, the two ends of the double-layer stent-graft are provided with The taper of the extension, that is, the diameter at both ends of the double-layer covered stent gradually decreases with the decrease of the diameter of the proximal and distal vessels of the thoracic aorta, and the diameter at both ends of the double-layer covered stent is from the middle to the two ends. Tapering taper.

Further, the inner metal stent and the outer metal stent are both braided from nickel-titanium alloy wire or laser-engraved from a nickel-titanium alloy thin tube.

Metal materials with excellent mechanical properties, such as nickel-titanium alloy, are often used for the bracket part to provide sufficient support. Nickel-titanium alloy materials also have shape memory properties, which can automatically restore their own plastic deformation to their original shape at a certain temperature, making them elastic and capable of restoring their shape. The metal inner stent and the metal outer stent braided by nickel-titanium alloy wire have a large number of hollow pores. Because the nickel-titanium alloy wire is very thin, the thickness of the braided metal inner stent and metal outer stent is very thin , the outer stent of the double-layer covered stent will be embedded in the blood vessel, and the elastic biofilm will fit closely with the blood vessel to achieve the effect of hemostasis. The metal inner stent and the metal outer stent are laser-engraved to form a predetermined hollow hole, and the elastic biofilm and blood vessels fit closely in the hole to achieve the effect of hemostasis.

A double-layer film-covered stent provided by the utility model adopts a double-layer stent structure of an outer layer stent and an inner layer stent, and covers the biofilm between the outer layer stent and the inner layer stent to form a solid stent structure, so that The stent structure is not easy to deform, reducing the membrane gap caused by the deformation of the stent structure and the vascular endoleak caused by the stent piercing the membrane.

Description of drawings

Fig. 1 is the structural representation of the utility model;

In the figure: 1—metal outer stent, 2—metal inner stent, 3—biofilm.

Detailed ways

The utility model will be further described in detail below in conjunction with the examples, but the implementation of the utility model is not limited thereto.

Example 1

As shown in Figure 1, the double-layer covered stent is a tubular structure closely attached to the inside of the blood vessel wall, including a stent structure and a biofilm 3 covering the stent structure, and the stent structure includes a metal inner layer stent 2 and the outer metal stent 1 sheathed outside the inner metal stent 2 , the biofilm 3 is covered between the outer metal stent 1 and the inner metal stent 2 .

The biofilm 3 is covered between the outer metal stent 1 and the inner metal stent 2 and closely adheres to the inner surface of the outer metal stent 1 and the outer surface of the inner metal stent 2, so that it is closely attached to the blood vessel wall Medial, to achieve a good hemostatic effect. The outer diameter of the double-layer stent-graft is slightly larger than the inner diameter of the blood vessel. After the double-layer stent-graft is implanted, the double-layer stent-graft adheres closely to the inner wall of the blood vessel to achieve the effect of hemostasis. Due to the supporting effect of the outer stent and the inner stent, the internal and external force of the biofilm 3 is uniform, so that the biofilm 3 is not easily deformed, damaged, and ruptured, and the endoleak caused by the membrane gap and the stent piercing the membrane is avoided.

Example 2

This embodiment is improved on the basis of Embodiment 1. The improvement is that: when the double-layer covered stent-graft is placed on the thoracic aorta where the proximal and distal vessel diameters gradually decrease, the double-layer The two ends of the stent-graft are provided with tapers extending toward the two ends of the double-layer stent-graft, that is, the diameters of the two ends of the double-layer stent-graft gradually decrease with the diameter of the blood vessels at the proximal and distal ends of the thoracic aorta. Small, double-layered stent-grafts form a taper at both ends that tapers in diameter from the middle to the ends.

Other parts in this embodiment are basically the same as those in Embodiment 1, so details will not be repeated one by one.

Example 3

This embodiment is improved on the basis of Embodiment 1 or 2, and the improvement is that: the inner metal stent 2 and the outer metal stent 1 are braided with nickel-titanium alloy wires.

Metal materials with excellent mechanical properties, such as nickel-titanium alloy, are often used for the bracket part to provide sufficient support. Nickel-titanium alloy materials also have shape memory properties, which can automatically restore their own plastic deformation to their original shape at a certain temperature, making them elastic and capable of restoring their shape. The metal inner stent 2 and the metal outer stent 1 braided by nickel-titanium alloy wire have a large number of hollow pores. Since the nickel-titanium alloy wire is very thin, the braided metal inner stent 2 and metal outer stent 1 The thickness of the double-layer stent graft is very thin, and the outer stent of the double-layer covered stent will be embedded in the blood vessel, and the elastic biofilm 3 fits closely with the blood vessel to achieve the effect of hemostasis.

Both the metal outer stent 1 and the technical inner stent can also be formed by laser engraving of nickel-titanium alloy thin tubes.

The above is only a preferred embodiment of the utility model, and does not limit the utility model in any form. Any simple modification or equivalent change made to the above embodiments according to the technical essence of the utility model falls within the scope of the present utility model. Within the protection scope of the present utility model.

Claims (4)

1. the double-deck overlay film frame, for the tubular structure for being fitted tightly over blood vessel wall inner side, including supporting structure and bracket knot is overlayed on Biomembrane (3) on structure, it is characterised in that: the supporting structure includes inner metallic layer bracket (2) and is set in inner metallic layer branch The metal outer bracket (1) of frame (2) outside, the biomembrane (3) overlay on metal outer bracket (1) and inner metallic layer bracket (2) it Between.

2. bilayer overlay film frame according to claim 1, it is characterised in that: when the double-deck overlay film frame is arranged in proximal end When the aorta pectoralis being gradually reduced with distal vessels diameter, the bilayer overlay film frame both ends are provided with to the double-deck overlay film frame The taper that both ends end extends.

3. bilayer overlay film frame according to claim 1, it is characterised in that: outside the inner metallic layer bracket (2) and metal Layer bracket (1) is that nitinol alloy wire weaves.

4. bilayer overlay film frame according to claim 1, it is characterised in that: outside the inner metallic layer bracket (2) and metal Layer bracket (1) is that Nitinol light wall pipe laser engraving forms.