RU25687U1 - SINGLE XENOTRANSPLANT - Google Patents

Description

The utility model relates to medicine, namely to bioprosthetics of heart valves.

A single-leaf xenopericardial graft is known, which is a rectangular base with a specially shaped sash made of xenopericardium or a calf liver glisson capsule and used in the surgical treatment of Fallot tetrads, which is a reasonable alternative to valve-containing prostheses (conduits). (Podzolkov V.P., Ivanitsky A.V., Plotnikova L.R., Dekhkanov O.Kh., Zotova L.M., Kiselev M.A., Sadovnikova E.V., Safonova N.I., Dvinyaninova NB The function of the xenopericardial patch with a mono-shutter depending on the observation time and its effect on the quality of long-term results in the radical correction of the Fallot tetrad // Breast and cardiovascular surgery, 1998, N 2, pp. 10-15).

The basic principle laid down in the design of single-leaf xenografts is the ability to adequately expand the hypoplastic cone of the right ventricle and the trunk of the pulmonary artery in combination with the restoration of the closure function of the pulmonary artery valves.

The base of the xenograft is sutured to the edges of the incision of the hypoplastic cone of the right ventricle and the trunk of the pulmonary artery, forming the front wall. The size of the xenograft base and the size of the single-leaf are selected depending on the size of the initial and required diameter of the pulmonary valve ring and pulmonary artery trunk. When

of necessity, a flap is cut out from the free edge of the monostasis in such a way that its edge fits tightly with its own undeveloped pulmonary valve valves of the recipient, preventing the backflow of blood.

Despite its good function, a single-leaf xenograft does not completely eliminate pulmonary regurgitation due to the fact that the shape of the locking element (single-leaf) does not provide a tight closure of the lumen of the newly formed trunk of the pulmonary artery. Cutting an additional flap in place is accompanied by an increase in the operation time and possible errors in the measurement and cutting of the tissue, and also leads to the fact that the edge of the single-leaf thus formed becomes too massive. This leads to an increase in the pressure gradient on the valve, as well as to the deformation of the excess leaf tissue in the region of its free edge, which leads to rapid wear and deterioration of the locking function. This in turn leads to the development of heart failure as a result of heart overload with pulmonary regurgitation.

The technical task is to ensure complete restoration of the closure function at the site of excised hypoplastic pulmonary valves.

The problem is achieved through the use of a locking element (monostasis) with a special shape of the free edge.

The figure shows a xenograft in two projections.

A single-leaf transplant is made from xenotissue, processed according to a known method, including stabilization, anticalcium treatment and sterilization. Width of base (1) of a single-leaf xenograft, with which

the trunk of the pulmonary artery expands, it must correspond to the semicircle of the newly formed trunk, leaving an allowance for hemming with a curled seam to the edges of the incision. The graft base length is standard. The width and height of the obturator element (mono-gate) (2) is selected depending on the diameter of the newly formed trunk of the pulmonary artery based on the calculations (see table), while the free edge of the mono-gate should be completely in contact with the opposite wall of the newly formed trunk of the pulmonary artery. The valves of the recipient's own pulmonary valve do not participate in the formation of the obturator element of the newly formed pulmonary trunk and are excised. The mono-gate is hemmed to the base with a continuous twisted seam, then the supporting frame (3) of biologically inert synthetic fabric is hemmed from the outside.

The shape of the single-leaf is selected in such a way as to ensure complete overlap of the cylindrical lumen of the vessel, and the free edge due to the oval shape of the leaf does not sag in the bloodstream, creating an obstacle, but rather performs a full locking function due to the snug fit to the back surface of the newly created trunk of the pulmonary artery.

A single-leaf xenograft is implanted after opening a sterile container in which it is stored in a sterilizing solution, and washing in sterile physiological saline, with a change of solution.

A single-leaf xenograft works as follows. When the right ventricle of the heart contracts, under pressure xenograft mono-gate (2), excessive pressure is created, the mono-gate opens and is pressed by the blood flow to the base (1)

xenograft. Blood enters the pulmonary artery. Then the phase of ventricular relaxation begins, accompanied by the appearance of a reverse flow of blood from the pulmonary artery. When a reverse flow of blood occurs, it fills the monostate, the free edge of the monostate is in contact with the opposite wall of the trunk of the pulmonary artery, preventing the reverse flow of blood. Then the ventricular contraction follows again, and the cycle repeats.

Table for calculating the size of single-leaf xenografts depending on the diameter of the pulmonary trunk.

Sizes, mm

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Claims (1)

A single-leaf xenograft consisting of a base with a locking element sewn to it in the form of a mono-gate, characterized in that in addition to the base, the supporting frame of the mono-gate is made of synthetic material, and the mono-gate has an arched free edge, the radius of curvature of which depends on the diameter of the pulmonary trunk.