RU196616U1 - VASCULAR ENDOPROTHESIS "SOFT ELEPHANT TRUNK" FOR HYBRID TREATMENT OF BREAST AORTIC DECOMPOSITION - Google Patents

Abstract

We propose a vascular endoprosthesis "soft elephant trunk" for hybrid treatment of thoracic aortic dissection, which is a tube made of dacron with a diameter of 20-32 mm, characterized in that the tube is 200 mm long, while the tube is supported by nitinol wires with sinusoidal "crowns" repeating two times around the perimeter 50 mm below the proximal end of the vascular endoprosthesis, arranged in parallel with six rows in length at intervals of 20 mm, in addition, contains an additional lower nitinol wire "crown" in the form of nosoids, repeated around the perimeter 16 times, the diameter of all nitinol wires of the "crown" decreases distally: the top three nitinol wires of the "crown" - 0.5 mm, the three lower ones - 0.4 mm, the additional lower nitinol wire "crown" - 0, 25 mm is located 15 mm above the distal end of the vascular endoprosthesis. The proposed vascular endoprosthesis "soft elephant trunk" for hybrid treatment of thoracic aortic dissection differs from the existing E-Vita Open PLUS practice in the absence of the part represented by a vascular prosthesis for simultaneous rivers structures of the arch and ascending aorta. To replace the ascending and the aortic arch, any diameter-optimal linear or multi-jaw prosthesis that connects to the vascular endoprosthesis with a soft elephant trunk for hybrid treatment of thoracic aortic dissection using the proximal end, represented by a 50 mm vascular prosthesis fragment, can be used. The vascular endoprosthesis "soft elephant trunk" for the hybrid treatment of stratification of the thoracic aorta provides stabilization in the true canal of the stratified aorta, makes it possible to reduce the load and traumatic effect on the stratified intima due to a downward decrease in the diameter and elasticity of nitinol wires.

Description

The invention relates to the field of cardiovascular surgery, in particular to a device for hybrid surgical treatment of dissection of the thoracic and thoracoabdominal aorta. It can be used in specialized departments of cardiovascular surgery.

Vascular surgery can not do without the use of vascular prostheses. Vascular prostheses are mainly used in the reconstruction of arteries of different diameters. Currently, with the progress of surgical technique, anesthesiology and perfusion therapy, complex interventions are being performed to replace both individual parts and the entire aorta with artificial aortic prostheses. Hybrid technologies that can significantly reduce the invasiveness of surgical interventions on the aorta without reducing radicalism imply a partial replacement of the aorta in the surgical wound with a vascular prosthesis to remove the affected area and strengthen the adjacent part of the aorta by introducing an endoprosthesis-stent into the lumen of the affected vessel. Currently, hybrid techniques are increasingly being introduced into practice in the treatment of thoracic, thoracoabdominal aneurysms and aortic dissections. This is due to the desire to reduce trauma in the surgical treatment of this severe group of patients. The most progressive at present is the one-stage hybrid approach, combining open surgical techniques for reconstruction of the aortic root, its ascending section, arch and endovascular intervention in the proximal section of the descending thoracic aorta, which suggests the restoration of normal functional aortic anatomy over a significant period during one operation.

To perform this surgical procedure, the most popular special hybrid prosthesis E-Vita Open PLUS (Jotec GmbH) has been constructed. This prosthesis is designed specifically for the treatment of type I dissection and diffuse aortic aneurysms from sternotomic access. (Quinones-Baldrich W, Jimenez JC, DeRubertis B, Moore WS. Combined endovascular and surgical approach (CESA) to thoracoabdominal aortic pathology: a 10-year experience // J Vase Surg. - 2009. - Vol. 49. - P. 1125-1134 Koullias, GJ State-of-the-art of hybrid procedures for the aortic arch: A meta-analysis / Koullias GJ, Wheatly GH // Ann. Thorac. Surg. - 2010. - Vol. 90. P. 689- 697;)

The hybrid vascular prosthesis E-Vita Open PLUS (Jotec GmbH) is a dacron tube. The proximal corrugated segment, the same as the standard vascular prosthesis, is intended for reconstruction on the ascending and aortic arch. The distal part of the same length, represented by a vascular stent graft, allows reconstruction of the descending aorta during one operation, avoiding the second stage of surgical intervention. The tube along this extent is straightened and fixed inside the aorta by nitinol wires "crowns" sewn to the tube located along seven rows in a mirror arrangement and repeating transverse 5 times around the perimeter. At the end, the proximal part of the prosthesis is screwed into the distal one, it is in a compressed state until it is introduced retrogradely into the descending aorta by a special conductor and after the conductor is removed, it straightens. At the stage of reconstruction of the ascending aorta and its arch, the proximal part of the prosthesis is turned out using special threads of the holders.

The disadvantage of the proximal vascular part of the hybrid prosthesis E-Vita Open PLUS presented by the linear prosthesis is that when reconstructing the aortic arch and its branches, if necessary, separate prosthetics, requires the use of a multi-jaw prosthesis. Another important disadvantage of the distal part is the absence of a decrease in the stiffness of the nitinol wires of the “corona” in the distal direction and the location of the lower nitinol wire of the “corona” directly along the distal perimeter, which has a traumatic effect on the stratified intima, provoking its breaks and the formation of new breaks in the postoperative period.

The task is to create an optimal vascular endoprosthesis, which as part of a hybrid reconstruction allows freedom of choice of the proximal part involved in prosthetics of the ascending aorta and arch, and which reduces the effect of the radial force of the endoprosthesis in its distal part on the stratified intima with the prevention of possible rupture,

A vascular endoprosthesis "soft elephant trunk" is proposed for the hybrid treatment of thoracic aortic dissection, which is a tube made of dacron with a diameter of 20-32 mm., 200 mm long.

The diameter of the prosthesis has a variable value due to the different diameters of the aorta in different people. The presented interval corresponds to the most common aortic diameters. The diameter of the aorta is preliminarily estimated according to computed tomography with contrast (MSCT) and the final choice of the diameter of the prosthesis is carried out during the operation with special templates of different diameters that are inserted into the aortic lumen. (Fig. 1)

The vascular endoprosthesis "soft elephant trunk" for the hybrid treatment of stratification of the thoracic aorta is supported by sinusoidal corona-shaped wires 50 mm below the proximal end of the endoprosthesis. The length of the proximal part of the vascular endoprosthesis "soft elephant trunk" for hybrid treatment of stratification of the thoracic aorta is 50 mm, it is unchanged and allows the surgeon to freely establish the required depth of fixation and positioning of the vascular endoprosthesis presented, and also to form an anastomosis with a prosthesis of the aortic arch. Excess tissue of this part of the prosthesis is cut off during the formation of the anastomosis.

Nitinol wires of the "crown" in the form of a sinusoid repeating twice around the perimeter are parallel to six rows at intervals of 20 mm. The distal end is reinforced with an additional nitinol wire "crown" located transverse around the perimeter in the form of a sinusoid repeating 16 times. In order to prevent injury when the distal end of the prosthesis comes into contact with the intima, the additional lower nitinol wire “crown” is located 15 mm above the distal end of the prosthesis. The diameter and, accordingly, the elasticity of the corona nitinol wires decreases distally in order to reduce the traumatic effect on the intima: the top three corona nitinol wires are 0.5 mm, the three lower ones are 0.4 mm lower, the additional corona nitinol wire which is inserted to achieve greater softness and suppleness of the lower edge located at 15 mm above the distal end of the vascular endoprosthesis - 0.25 mm

The distance between the nitinol wires of the “crowns” of the vascular endoprosthesis “soft elephant trunk” for the hybrid treatment of thoracic aortic dissection - 20 mm, was calculated by scientists in earlier studies and represents the largest interval that can prevent prosthesis bends in the deformed canal. The fundamental difference between this vascular endoprosthesis is that the conditions are created from top to bottom - reducing the thickness of the nitinol wire of the "crown" to gradually reduce the radial strength of the hybrid prosthesis, which is installed in the true channel of the aorta, and the distal edge without nitinol wires of the "crown" completely eliminates the local the load on the stratified intima, which is the main method of preventing its rupture along the edge of the vascular endoprosthesis - such complications are described (in the literature dSine).

The distance between the nitinol wires of the “crowns” in the form of a sinusoid is 20 mm, the number of sinusoids around the perimeter of the main nitinol wires of the “crowns” is 2 and the additional 16, the thickness of all nitinol wires of the “crowns” and the length of all parts of the vascular endoprosthesis “soft trunk of an elephant” for hybrid treatment of thoracic aortic dissection, they were carefully calculated and studied during in-vitro experiments, just such a combination made it possible not to bend the prosthesis in the aortic canal, not to obstruct the blood flow, while maintaining a given shape and fected the main task of a gradual reduction of the radial force of the proposed utility model.

The proposed vascular endoprosthesis "soft elephant trunk" for hybrid treatment of stratification of the thoracic aorta and signs that distinguish it from those known in the medical and patent literature have not been found, which allows us to conclude that its criterion of "novelty" is met.

The vascular endoprosthesis “soft elephant trunk” for hybrid treatment of thoracic aortic dissection differs from the existing practice of E-Vita Open PLUS in the absence of the part represented by the vascular prosthesis providing the possibility of reconstruction of the arch and ascending aorta, the proximal part of the 50 mm vascular endoprosthesis free of nitinol wires ”coronas "and designed to position the presented vascular endoprosthesis, as well as to form an anastomosis with an aortic arch prosthesis supporting nitinol sine-shaped “corona” wires repeated twice perimeter parallel to six rows in length with 20 mm intervals, the presence of an additional lower sinusoid-shaped “corona” nitronol wire repeated 16 times located 15 mm above the distal end of the vascular endoprosthesis, with the decreasing diameter of the nitinol wires "corona" in the distal direction from 0.5 mm to 0.25 mm

The proposed vascular endoprosthesis "soft elephant trunk" for the hybrid treatment of stratification of the thoracic aorta allows the use of a linear or multi-jaw prosthesis of any diameter for simultaneous replacement of the ascending and aortic arch. The vascular endoprosthesis "soft elephant trunk" for hybrid treatment of stratification of the thoracic aorta, providing stabilization in the true channel of the stratified aorta, makes it possible to reduce the load and traumatic effect on the stratified intima due to a downward decrease in the diameter and elasticity of nitinol wires of the "corona" and the presence of a soft distal end of the prosthesis, which significantly reduces the risk of rupture of intimacy.

Claims (1)

Vascular endoprosthesis "soft elephant trunk" for the hybrid treatment of thoracic aortic dissection, which is a tube of dacron with a diameter of 20-32 mm, characterized in that the tube is 200 mm long, while the tube is supported by nitinol wires with "sinusoidal" crowns repeated twice around the perimeter 50 mm below the proximal end of the vascular endoprosthesis, arranged in parallel with six rows along the length of 20 mm gaps, in addition, contains an additional sinusoid-shaped “crown” lower nitinol wire, rep bending around the perimeter 16 times, the diameter of all nitinol wires of the “crown” decreases distally: the top three nitinol wires of the “crown” are 0.5 mm, the three lower ones are 0.4 mm, the additional lower nitinol wire of the “crown” is 0.25 mm located 15 mm above the distal end of the vascular endoprosthesis.

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