System for stent-graft implantation in cases of injury to major vessels

Abstract

FIELD: cardiovascular surgery.SUBSTANCE: restoration of the integrity of major arteries when they are injured by doctors without vascular surgery skills in the shortest possible time and without the use of expensive equipment. A modern alternative method for restoring the integrity of the main vessel is proposed, which has the following advantages: the possibility of surgery in anatomically difficult to access areas, an objective reduction in the area of operative access and, as a result, trauma to the patient, a significant reduction in surgical intervention (5-10 minutes for complete restoration of the integrity of the vessel), simplification of the surgical intervention for restoring the integrity of the vessel with the possibility of performing the intervention by inexperienced doctors, performing the operation in a regular operating room without expensive equipment in an advanced medical unit with the final restoration of the main vessel. The solution to this problem is achieved by a stent-graft implantation system for major vessel injuries, which includes a nitinol stent coated with synthetic fabric. The stent-graft is folded at low temperatures and inserted into a vascular prosthesis. The prosthesis is impregnated with anticoagulants and antibiotics, and a tearable outer polymer coating is used in the distal and proximal sections of the stent-graft.EFFECT: possibility of surgery in anatomically difficult to access areas, an objective reduction in the area of operative access, simplification of the surgical intervention.1 cl, 4 dwg

Description

[0001] The invention relates to medicine, namely to cardiovascular surgery, and allows for the restoration of the integrity of major arteries when they are injured by doctors without vascular surgery skills in the shortest possible time and without the use of expensive equipment.

[0002] In cases of major vessel integrity damage, the primary method for stopping bleeding and restoring blood flow to dependent organs is open surgical suturing and replacement of the target vessel using autogenous, synthetic, and xenografts, using vascular sutures. Mandatory conditions for these interventions include: extended access to the proximal and distal edges of the damaged vessel, anatomical accessibility of the vessel, and the timeframe and skill of the vascular surgeon. Endovascular stent graft implantation is an alternative to open surgery. Disadvantages of this method include the availability of angiographic equipment, the wide range of consumables, and the skill of the endovascular surgeon.

[0003] Currently, only one similar design exists (Application: 2018139231, Russian Patent No. 189307, November 6, 2018), but it has several drawbacks. First and foremost, preparing the prosthesis for implantation is difficult, requiring cold water to alter the profile of the nitinol stent at the proximal and distal ends of the prosthesis. Furthermore, aligning the artery and prosthesis is challenging (this is not required in the present invention), which impacts the quality of surgical correction and the incidence of postoperative complications. Other stent grafts require expensive equipment and consumables for implantation, which are typically unavailable in peripheral medical facilities or under extreme medical conditions.

[0004] A modern alternative method for restoring the integrity of the main vessel is proposed, which has the following advantages:

[0005] 1. Possibility of surgery in anatomically difficult to access areas.

[0006] 2. Objective reduction of the surgical access area and, as a consequence, patient trauma.

[0007] 3. Significant reduction in surgical time (5-10 minutes for complete restoration of vessel integrity).

[0008] 4. Simplification of the surgical procedure for restoring the integrity of the vessel when the intervention can be performed by inexperienced doctors.

[0009] 5. Performing the operation in a regular operating room without expensive equipment in an advanced medical unit with final restoration of the main vessel.

[0010] The solution to the problem is ensured by the fact that the system for implanting a stent graft in case of injury to the main vessels includes a nitinol stent folded at a low temperature and installed inside a PTFE vascular prosthesis impregnated with anticoagulants and antibiotics, while at the ends of the stent graft not covered by the vascular prosthesis there are stent crowns for fixing the stent graft in the lumen of the vessel, and on the distal and proximal sections of the stent graft a tearable outer coating made of polymer is used to fix the stent graft in the folded state.

[0011] The invention is illustrated in Fig. 1, which shows the external appearance of the stent graft in its expanded form. Fig. 2 shows the external appearance of the stent graft in its folded form. Fig. 3 shows the stage of stent graft placement within the vessel (the moment of removal of the tear-off coating and the deployment and fixation of the stent graft in the lumen of the damaged vessel). Fig. 4 shows the external appearance of the stent graft after implantation in the damaged artery.

[0012] The system contains: 1 – synthetic coating; 2 – nitinol stent; 3 – stent crown for fixing the prosthesis in the lumen of the vessel; 4 – tearable coating of the stent graft; 5 – parts of the damaged vessel.

[0013] The device consists of:

[0014] 1. Self-expanding peripheral nitinol stent (2) (metal with memory at human body temperature).

[0015] 2. Vascular prosthesis made of PTFE and other synthetic material used for open vascular prosthetics, impregnated with anticoagulants and antibiotics (1).

[0016] 3. A tearable outer polymer coating on the distal and proximal portions of the stent graft (the material of the tearable introducer) for fixation of the stent graft in the folded state. This solution differs in the stent graft design (the presence of a polymer coating similar to the tearable introducer), allowing for its implantation not using the classic endovascular technique, but directly into the wound, without the use of additional consumables or angiographic equipment. Furthermore, this procedure does not require specialized endovascular surgical skills and can be performed by a general surgeon (4).

[0017] Assembled: a flexible nitinol stent, folded at low temperature, is installed inside the vascular prosthesis; this structure is compressed and packed inside a burst shell (Fig. 2). It is planned to develop a range of stent graft sizes with a diameter of 5, 6, 7, 8, 10, 12 mm; lengths of 40, 60, 80 mm.

[0018] Installation Method

[0019] 1. Inspection of the site of the vessel's integrity violation, stopping the bleeding, taking the ends of the vessel with vascular clamps or holders, cleaning the wound, preparing the distal and proximal sections of the vessel (assessment of antegrade and retrograde blood flow, use of a Fogarty catheter), excision of non-viable tissue.

[0020] 2. Selection of a stent graft based on the size of the damaged vessel, introduction of heparin into the vascular bed.

[0021] 3. Installation of the proximal and distal sections of the stent graft into the corresponding ends of the damaged vessel.

[0022] 4. Removing the rupture membranes (Fig. 3).

[0023] 5. Restoring the integrity of the vessel, monitoring the operation of the stent graft (for thrombosis, tightness), peripheral pulse (Fig. 4).

[0024] The system is designed like a classic nitinol stent graft and consists of a nitinol stent covered with synthetic fabric. When unfolded, the stent graft has a tubular shape. However, at the manufacturing plant, it is shipped folded and equipped with a delivery system, allowing it to be advanced from the puncture site into the target vessel and implanted. The difference with this device is that it does not have a delivery system, and the stent graft is advanced directly into the affected vessel. Consequently, angiographic imaging and contrast agent administration are not required for visualization and guidance of the stent graft. Implantation and deployment of the stent graft are performed under direct visual control by the surgeon directly in the wound.

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