More particularly, this invention relates to an adapter of the above mentioned kind that enables in reliable and economically feasible way to simplify and speed-up the installation of vascular anastomoses in order to improve the results that can be obtained.

It is known that one of the most frequent surgical intervents is the installation off a vascular by-pass, which represents the surgical treatment of occlusive diseases of arterial, venous or lymphatic vessels as well as in aneurysms. In particular, a vascular by-pass in which an artifact conjunction between interested hollow structures is realized by means of a prosthetic structure, becomes necessary in all those subjects in which particular disease conditions or traumatic events resulted into stenosis, occlusion or dilatation of the vessels.

The installation of a vascular by-pass provides for installation of a connection bridge made of bio-compatible or biologic (autologous, homologous or eterologous) synthetic material designed to span the deteriorated segment, in order to restore the normal arterial, venous or lymphatic circulation. When extended vascular pathologies are involved, the vessels interested in this intervent can be two or more than two. The intervent includes the insertion of the vascular prosthesis, suitably dimensioned by the surgeon during the intervent itself, upon suitably shaping its ends according to the needs (for instance with a so-called clarine beak cut), onto the one or more interested vessels upstream and downstream the deteriorated segment.

The difficulties connected with installing a vascular anastomosis (namely the suturation between interested hollow structures) are quite apparent to those skilled in the art. The problems arising in suitably shaping the connection orifices as well as in inserting the vascular prosthesis into the usually weakened walls of the interested vessels can be mentioned by way of exemplification.

This entails intervents of extremely long durations, variable as a function of the difficulties to be solved, that can make it necessary to realize a number of anastomoses during the same intervent. In this respect, it has been shown that, for instance, a prolonge duration of an intervent amounts to a significant infection risk for the vascular prosthesis, as well as to an increased surgical risk in general terms.

Furthermore, the outcome of the intervents depends in noticeable amount on the specific skillness of the surgeon, with the risk of technical inaccuracies that can make a reintervention necessary.

Again, the difficulties in vascular anostomoses make the installation of a by-pass on vessels of small diameter very hard.

Additionally, the recently performed by-pass intervents in the frame of video-aided surgery contemplate the realization of the anastomoses as the moment of maximum technical difficulty.

In this contest, it is the object of this invention, therefore, to provide in reliable and economically feasible manner all suitable means to solve all above mentioned problems and to enable to simplify and to speed-up the realization of vascular anastomoses, thereby improving and making the results of such operations as much as possible independent of the skillness of the surgeon.

It is specific subject matter of this invention an adapter for vascular anastomoses, having perimetral edges, characterized in that it comprises at least one main conduit and at least one branch conduit, the prosthesis being realized in bio-compatible material, preferably Dacron@ and/or GoreTex and/or PTFE and/or polyurethane and/or NitinolE and/or ePTFE.

According to this invention, the adapter can comprise a single main conduit and the axes of the main conduit and of said at least one branch conduit can include an acute angle in the range of 15° to 75°, preferably in the range of 25° to 45°.

Still according to this invention, the adapter can comprise two main conduits and a single branch conduit.

Further according to this invention, at least one branch conduit can comprise a second order branch conduit, the axes of said at least one branch conduit and of said at least one second order branch conduit including an acute angle in the range of 15° to 75°, preferably in the range of 25° to 45°.

Preferably according to this invention, at least one of the conduits of the adapter is of cylindrical or frusto-conical shape and/or it has a circular cross-section.

Again according to this invention, at least one of the conduits of the adapter can have one or more apertures in its external wall.

Again according to this invention, at least one of the conduits of the adapter can be provided with suitably shaped weakness lines in its external wall adapted to be cut so as to remove at least a portion of said external wall.

Preferably according to this invention, said perimetral edges are tapered and/or realized with partially bio-degradable and/or shape recovering materials.

Further according to this invention, at least one of the conduits of the adapter can be provided with an internal metal bio-compatible core, preferably of steel and/or titanium and/or a shape recovering material.

This invention will be hereinafter described, by way of illustration, not by way of limitation, according to its preferred embodiments, by particularly referring to the Figures of the enclosed drawings, in which: Figure 1 is a perspective view of a first embodiment of the adapter for vascular anastomoses according to this invention, Figure 2 is a perspective view of a second embodiment of the adapter for vascular anastomoses according to this invention, Figure 3 is a perspective view of a third embodiment of the adapter for vascular anastomoses according to this invention, Figure 4 is a perspective view of a fourth embodiment of the adapter for vascular anastomoses according to this invention.

Similar reference numerals will be utilized in the following description to designate similar items in the Figures.

By referring now to Figure 1, it can be observed that the adapter for vascular anastomoses according to this invention comprises a main conduit 1 communicating with a branch conduit 2. Said main conduit 1 and said branch conduit 2 have a cylindrical or frusto-conical shape, with circular cross-section. The axes of said main conduit 1 and said branch conduit 2 include an acute angle a in the range of 15° to 75°, preferably in the range of 25° to 45°.

The adapter according to this invention is realized with bio- compatible materials, such as, for instance, Dacron@, Gore-Tex@), PTFE, polyurethane, Nitinol@, ePTFE.

As it appears in Figure 1, the main conduit 1 communicates with a single branch conduit 2 and the length of said main conduit 1 is greater than the length of said branch conduit 2. It should be understood,

however, that those skilled in the art will be certainly able to modify the adapter according to this invention by providing more than one branch conduit 2 communicating with the main conduit 1 and/or said main conduit 1 can also be no longer than said branch conduit 2, without so departing from the scope of this invention.

Aiming at better illustrating this invention, the employment modes of the preferred embodiment of the adapter for vascular anastomoses will be hereinbelow described, in the assumption that similar modes also apply for the remaining embodiments.

During the realization of a vascular anastomosis, for performing the connection between the vascular prosthesis and the interested vessel, it sufficient to cut open the wall of the interested vessel, to insert the main conduit 1 of the adapter thereinto and to fix it in place. The vascular prosthesis is subsequently externally fixed to the free end of the branch conduit 2 of the adapter.

Aiming at minimizing the step effect that is generated in the lumen of the vessel as well as at enabling an optimum match to be realized between prosthesis and vessel, the free ends of said main conduit 1 can be tapered and/or realized with special partially bio- degradable and/or foamable materials of shape recovering type, that is to say such materials that at temperatures lower than the physiologic temperatures can be stored in slightly deformed condition and at physiologic temperatures they recover their original shape. As far as the adapter according to this invention in concerned, the free ends of said main conduit 1, realized with the above mentioned shape recovering materials, could also be maintained in a compressed diameter configuration and, as soon as they are warmed-up by contact with the blood or lymph stream, they dilatate so as to adhere to the internal wall of the vessel into which the adapter is inserted.

It will be apparent to those skilled in the art that, by utilizing the adapter according to this invention, the installation of a vascular anastomosis is noticeably simplified, which results into dramatically decreasing the necessary times for execution of the related operations as well as into significantly improving the outcome that can be achieved, which, in turn, is substantially independent of the operator's skillness.

By referring to figure 2, it can be observed that a second embodiment of the adapter according to this invention further comprises a

second order branch conduit 3 departing from said branch conduit 2. Said second order branch conduit 3 also has a cylindrical or frusto-conical shape with a circular cross-section. The axes of said branch conduit 2 and of said second order branch conduit 3 include an acute angle ß in the range of 15° to 75°, preferably in the range of 25° to 45°.

In Figure 2, the axes of the main conduit 1, of the branch conduit 2 and of the second order branch conduit 3 are co-planar. It should be understood, however, that those skilled in the art can easily modify the adapter according to this invention by realizing said three conduits 1,2 and 3 with non co-planar axes, without so departing from the scope of this invention.

The embodiment shown in Figure 2 enables to utilize the adapter according to this invention in realizing a vascular anastomosis in which it is necessary to realize multiple connections corresponding to a particular vessel. For instance, this is the case in which a prosthetic sequential aortal-femoral and femoral-distal bridge is to be realized such that an adapter according to Figure 2 can be inserted in corresponding position to the junction of the femoral vessel.

By referring to Figure 3, it can be observed that a third embodiment of the adapter according to this invention comprises two main conduits 1 and 1'both communicating with a branch conduit 2.

The embodiment of Figure 3 enables to utilize the adapter in performing arterial-venous vents, for instance in the case of dialyzed patients.

It is well known to those skilled in the art that a natural branching can be present in corresponding position to the connection of a vascular prosthesis. In such cases, the adapters illustrated in Figures 1,2 and 3 could occlude the related connection mouth. To overcome such a drawback, a fourth embodiment of the adapter according to this invention, as shown in Figure 4, provides for the main conduit 1 to have apertures 4 in its external wall adapted to prevent any connection mouths to further blood vessels from being occluded. Also in this case, the perimetral edges of said apertures 4 can be tapered and/or realized with special partially bio-degradable and/or foamable shape recovering materials so as to minimize the step effect that can be generated in the lumen of the vessel.

The adapter of Figure 4 is related to the one of Figure 1; it should be understood that similar embodiments of the adapter could also

be realized in respect of the embodiments of Figures 2 and 3, without so departing from the scope of this invention.

Furthermore, an adapter having three apertures 4 in its lateral wall is shown in Figure 4. It should be understood, however, that the number of said apertures 4 in the lateral wall can also be different from three, without so departing from the scope of this invention.

A fifth embodiment of the adapter according to this invention (not shown in the Figures) provides for the external wall of the main conduit to have suitably shaped weakness lines that can be cut open by the surgeon during the intervent in order to remove some portions of the external wall, so as to connect the adapter to junction areas where natural branchings are present.

Further embodiments of the adapter according to this invention can also be provided with a metal core, such as a wire network, internally incorporated with the material of the adapter itself. In particular, such core is realized with inert bio-compatible materials, such as, for instance, steel and titanium and/or foamable shape recovering materials.

The utilization of the adapter for vascular anastomoses according to this invention makes the application of by-passes to vessels of small diameter possible.

Furthermore, the simplification realized in installing a vascular anastomosis by utilizing the adapter according to this invention makes it easier to apply methods of video-assisted surgery, that are less invasive than the presently utilized conventional surgery techniques.

This invention has been hereinbefore explained by way of illustration, but not by way of limitation, according to its preferred embodiment, but it should be understood that those skilled in the art can made variations and/or changes therein without departing from the scope of this invention, as defined in the attached claims.