EP4475767A1

EP4475767A1 - Fistula sealing

Info

Publication number: EP4475767A1
Application number: EP23702838.6A
Authority: EP
Inventors: Vicente María LORENZO-ZÚÑIGA GARCÍA; Vicente PONS BELTRÁN; Rubén MARTÍN CABEZUELO; Ana VIDAURRE GARAYO; Guillermo VILARIÑO FELTRER; Isabel TORT AUSINA; Alberto José CAMPILLO FERNÁNDEZ
Original assignee: Universidad Politecnica de Valencia; Fundacion para la Investigacion del Hospital Universitario y Politecnico La Fe de La Comunidad Valenciana
Current assignee: Universidad Politecnica de Valencia; Fundacion para la Investigacion del Hospital Universitario y Politecnico La Fe de La Comunidad Valenciana
Priority date: 2022-02-07
Filing date: 2023-02-06
Publication date: 2024-12-18
Also published as: WO2023148383A1

Abstract

A sealant device to seal a cavity of a fistula is provided. The sealant device comprising a filling element to be filled with a filling fluid to contact the cavity in an expanded state; an approaching element having a holding portion to contact a tissue adjacent to the fistulous orifice, such that the adjacent wall tissue is held in a predefined position; and a connector to connect the filling element with the approaching element. A system and a method to seal the cavity is also provided.

Description

Fistula sealing

This application claims the benefit of European Patent Application EP22382100 filed on February 7th, 2022.

The present disclosure generally relates to devices, systems and methods for sealing fistulae, and more specifically, to a sealant device for sealing a cavity of a fistula, systems and methods.

BACKGROUND

A fistula is a medical disorder in which an abnormal cavity is generated. A fistula can also involve an abnormal connection between two hollow spaces of the body such as blood vessels, intestines, or other hollow organs. In the first case, the fistula is a blind hole connected to a physiologic lumen through a fistulous orifice. In the second case, the fistula has a tract with two opened ends.

Examples of the fistulae that generate a fistulous cavity can be the gastrointestinal fistulas owing to their location in the digestive tract. More specifically, post-surgical gastrointestinal fistulas or post-surgical fistulas are described. The post-surgical fistulas may be considered as medical complications due to gastrointestinal surgical procedures such as those associated with oncologic or metabolic bariatric surgery. In these surgical procedures anastomoses are usually performed.

Post-surgical fistulas may appear as a complication of an anastomosis of a physiologic lumen. When the anastomosis is performed, the practitioner may join two sections of the physiologic lumen. In some cases, post-surgical fistula appears in the region of the junction between the lumen sections. The junction may have stitches, making it difficult to close the fistulous orifice.

Postsurgical fistulas usually have a cavity or blind hole configuration, i.e., with only one opening to the physiological lumen.

Post-surgical fistula of the anastomosis, e.g. dehiscence or leak, may be a serious medical complication, and even a cause of postoperative mortality in digestive surgery. Upper gastrointestinal surgery may result in postsurgical complications, such as esophagogastric or gastrojejunal anastomosis leak, whose frequency in countries like Spain is 7.3% and 3.6% respectively. Incidence in anastomotic leak in colorectal surgery seems to remain stable over the last years, around 6.6 % for elective surgery and up to 22.2 % for emergency surgery.

A series of factors may favor the appearance of the postsurgical fistula of the anastomosis, such as advanced age, malnutrition, comorbidities, tumor stage, and emergency surgery. This complication may imply several imaging and endoscopic studies, long hospital stays, surgical reinterventions, admission in critical care units and may involve a considerable overuse of healthcare resources. Endoscopic management of gastrointestinal fistula may be a standard of care to avoid surgical reintervention.

No specific medical techniques are known so far to treat the complication of post- surgical fistula. Attempts have been made to implement techniques from other fields for this purpose. These techniques are intended at best to interrupt the flow of luminal content through the gastrointestinal defect.

The low efficacy of non-specific methods in postoperative fistulas may be caused by the particular conditions of those complications. For instance, postsurgical fistulas usually have a cavity or blind hole configuration, i.e., with only one opening to the physiological lumen. Therefore, closing techniques related to other types of fistulas with two end openings cannot be applied. Some comments regarding the latter will be set forth.

In fistulas with two open ends, for example between two hollow organs of the body, a plug can be placed in at least one of the ends and tensioned from the other open end to fix the plug. The respective walls of the two organs offer adequate support as they are relatively thick. Logically, this technique cannot be applied in a blind orifice, but if it were applied in post-surgical fistulas there would be a risk of increasing the size of the fistular orifice, as the tissue of the physiological lumen may be thinner.

Furthermore, presence of mucosal induration in postsurgical fistulas due to proximity to the mechanical surgical suture of the anastomosis may hinder the correct positioning and anchoring of clips; absence of stenosis in the cavity of the postsurgical fistula may facilitate migration of a stent or the like from the fistula; inability or difficulty to access along the digestive tract with specific tools such as an overtube to implant a vacuum system to reduce the size of the postsurgical fistula; possibility of causing bleeding if vacuum is applied to the postsurgical fistula; there is a risk of the walls of the fistulous cavity sticking together due to the vacuum; practical inability to maneuver an endoscope to perform endoscopic suturing; sealing fluids without containment may migrate through the fistulous orifice of the postsurgical fistula due to lack of adhesiveness; and possibility of interference with the functioning of heart, lung or abdominal organs if sealing material is applied to full obliteration in the mediastinum or peritoneum.

Therefore, there is still a need for sealant devices, systems and methods to seal cavities of fistulae that may resolve at least some of the aforementioned problems.

SUMMARY

In a first aspect, a sealant device to seal a cavity of a fistula is provided. The fistula has a fistulous orifice on a wall of a physiologic lumen. The sealant device comprising: a filling element to be filled with a filling fluid to contact, at least, a portion of the cavity in an expanded state; an approaching element having a holding portion to contact at least a part of a wall tissue adjacent to the fistulous orifice, such that the adjacent wall tissue is held in a predefined position relative to a longitudinal axis of the sealant device in the expanded state; a connector to connect the filling element with the approaching element.

In accordance with this aspect, a device is provided that may allow sealing or occluding the cavity of a fistula by virtue of the filling element and an approximation closure at the fistular or fistulous orifice. Closure by approximation of the wall tissue adjacent to the fistular orifice may be achieved despite mucosal indurations. Closure by approximation may be achieved by the action of the holding portion retaining the lumen wall tissue adjacent to or bordering the fistular orifice. The tissue may be retained in a predefined position with respect to the longitudinal axis of the sealant device. This way, the fistulous orifice at least does not become larger and may be occluded while the healing of the fistula.

In some cases, the longitudinal axis may coincide with the connector. The tissue of the wall of the lumen may be approached to the connector.

The closure of the fistulous orifice may be performed in the junction area of the anastomosis where stitches may be visible. The holding portion may allow to maintain and even approximate at least a part of the lumen wall tissue in the area adjacent to the fistular orifice. The approximation element may act as a bridging element for these tissues adjacent to the fistular orifice.

The predefined position may be related to a position where the edges or boundary of the fistulous orifice defines a predefined span or area. When the approaching element is positioned on the walls of the physiologic lumen, the approaching element may tend to reduce the span or area of the fistulous orifice.

The predefined position may be related to the size of the fistulous orifice. When the approaching element is positioned on the walls of the physiologic lumen, the approaching element may tend to reduce the size of the fistulous orifice.

In accordance with that aspect, the approaching element may help edges of the fistulous orifice to grow back together.

The sealant device may cause the edges of the fistulous orifice to be closer to each other.

The filling element may act in combination with the approaching element to enhance the occlusion of the fistulous orifice. The filling element may contact the inner side of the fistulous orifice in an expanded state or condition while the approaching element is retaining or holding the tissue of the lumen in the outer side of the fistulous orifice. This may allow an enhanced approaching of the tissue of the edge of the fistulous orifice to the longitudinal axis of the sealant device.

A device for the treatment of fistula cavities may be achieved that may avoid the use of systems intended for fistulas with two end openings. The use of systems that apply tension from opposite openings of the fistula tract to close the orifices may be avoided. This may avoid or at least reduce the risk of fistula enlargement and ischemia or necrosis due to impaired blood supply.

In some examples, the filling element may comprise an inflatable filling balloon. In this way, the material with which the fistula is filled may be contained without being released through the fistular orifice. The inclusion of filling material within the cavity may be controlled in a predetermined manner and the full obliteration may be avoided if required. Thus, fistulas in the mediastinum, peritoneum or retroperitoneum may be occluded, avoiding or at least reducing the risk of interfering with the heart, lungs or other organs in the area.

In some examples, the filling element may have a permeable cover to release at least a part of the filling fluid in the cavity. In this example, bioactive substances or agents, e.g., re-epithelializers or antibiotics, may be released into the fistula cavity. The latter may be useful in the example of post-surgical fistula, as they are blind and may be septic. Due to the characteristics of this particular example, the sealant device may achieve a combined effect of mechanical features and bioactive features, namely the closure by approximation and release of the bioactive substance. The bioactive substance may be related to a trophic, antibiotic and/or reparative action.

In an example where the filling element comprises an inflatable filling balloon and the approaching element comprises an inflatable approaching balloon, each of the filling element and the approaching element may be filled with different filling fluids from each other. This way, the filling element and the approaching element may release agents with different properties from each other through their outer wall or cover. For example, the fluid released by the approaching balloon may be intended to enhance tissue growth of the physiologic lumen wall. The fluid from the filling balloon may be intended to promote tissue growth where the cavity is defined.

In some examples, the sealant device may be carried by an endoscopic catheter. The endoscopic catheter may be able to reach a fistula in a wall of the small intestine or the like.

In examples, the fistula may be related to a gastrointestinal fistula. In some examples, the fistula may be a non-vascular fistula.

The expressions close, closure and the like, as used herein may be understood to mean an approximation of the edges of the fistulous orifice, at least to some degree.

The expression cavity as used herein may be understood to mean a blind hole.

The expression cavity may involve a single fistulous orifice in a wall of the physiological lumen. A bottom of the cavity may be arranged opposite to the fistulous orifice through the path of the cavity.

In the present disclosure the terms cavity or fistulous cavity are used interchangeably.

The fistulous orifice may have an inner side and an outer side. The outer side may face the physiologic lumen and the inner side may face the fistulous cavity.

The expression distal as used herein may be understood to mean the area farthest from the practitioner or the area which is to be closer to the fistula in use. For example, a distal end of a part is intended to be closer to a cavity of the fistula in use than a proximal end.

The expression proximal as used herein may be understood to mean the area closest to the practitioner or the area which is to be farthest to the fistula in use. For example, a proximal end of a part is intended to be farther to a cavity of the fistula in use than a distal end.

BRIEF DESCRIPTION OF THE DRAWINGS

Non-limiting examples of the present disclosure will be described in the following, with reference to the appended drawings, in which:

Figure 1 schematically illustrates a sealant device having an inflatable approaching element according to an example;

Figure 2 schematically illustrates the sealant device of Figure 1 with a catheter according to an example;

Figure 3 schematically illustrates a perspective view of the sealant device of Figure 1;

Figures 4 - 6 schematically illustrate the sealant device of Figure 2 with a catheter to seal a cavity of a fistula;

Figures 7 - 9 schematically illustrate a sealant device according to an example with a catheter to seal a cavity of a fistula;

Figures 10 - 13 schematically illustrate a sealant device according to a further example with a catheter to seal a cavity of a fistula;

Figure 14 schematically illustrates a sealant system according to an example;

Figure 15 schematically illustrates a sealant system according to a further example;

Figure 16 schematically illustrates some views of the actuation of the sealant device in a cavity of a physiological lumen according to an example; and

Figure 17 is a block diagram of an example of a method of the present disclosure.

DETAILED DESCRIPTION OF EXAMPLES

Figure 1 schematically illustrates a sealant device 100 having an inflatable approaching element 20 according to an example. In this Figure 1 it can be seen that a sealant device 100 of the present disclosure comprises a filling element 10 connected to an approaching element 20 through a connector 30.

Various examples of the sealant device relating to the digestive tract are included in this disclosure. However, the relation to the digestive tract is not to be understood as limiting, as other uses may be envisaged where abnormal cavities or blind holes are formed in other parts of the anatomy such as respiratory tract, urinary tract and/or gynecological tract.

In the present description, the fistula may be a non-vascular fistula and/or the fistula may be a gastrointestinal fistula.

The physiologic lumen may be non-vascular.

With regard to the digestive tract, the sealant device according to the present disclosure may be employed in conjunction with a catheter and an endoscope for the treatment of fistulas of the digestive tract which are remote from a natural orifice, e.g. mouth and anus. In the present disclosure different numerical references have been used to designate the same elements of the different examples of the sealant device for the sake of clarity.

In the attached figures, elements that are not visible are shown with dashed lines for the sake of clarity.

Figures 2 to 3 illustrate the example of the sealant device 100 shown in Figure 1. Particularly, in Figure 2 it is shown together with a catheter 40 that may be used to fill at least the filling element 10. Figure 3 allows the sealant device 100 to be seen in perspective. In all three Figures, the filling element 10 is illustrated in an expanded state, i.e., it has been at least partially filled with filling fluid FF. Particular details about filling of the sealant device will be provided later on.

In most of the Figures neither the cavity C nor the physiological lumen PL has been depicted for reasons of clarity. Catheter 40 may be partially depicted for clarity.

Returning to Figure 1 , it can be seen the sealant device 100 that comprises the filling element 10 to be filled with a filling fluid FF to contact, at least, a portion of the cavity C in an expanded state. The sealant device 100 comprises an approaching element 20 that has a holding portion 25. The holding portion may be configured to contact at least a part of the wall tissue WT adjacent to the fistulous orifice FO, such that the adjacent wall tissue WT is held in a predefined position relative to the longitudinal axis LA of the sealant device 100 in the expanded state. The device 100 comprises the connector 30 to connect the filling element 10 with the approaching element 20.

The approaching element may be able of or configured to reduce in size from a first or predefined size to a size or second size smaller than the first or predefined size, wherein the reduction in size occurs at least relative to the longitudinal axis LA of the sealant device 100, 200, 300. In some examples, this reduction in size of the approaching element may involve the holding portion 25 also reducing in size and/or moving closer to the longitudinal axis LA. For example, if the holding portion 25 comprises a surface with a geometric shape with respect to the longitudinal axis, the geometric shape may reduce in size and approach the longitudinal axis. In a more particular example, the holding portion 25 may define a continuous or discontinuous rim, isolated zones or points, etc. The reduction in size of the approaching element 20, 21 , 22 in combination with the approximation to the longitudinal axis LA, may help reduce the size or dimensions of the fistulous orifice FO, as the physiological lumen wall tissue may remain attached to the holding portion 25 during the reduction in size and approximation to the longitudinal axis of the holding portion 25.

In some examples, this reduction in size of the approaching element may be defined or achieved by an inflatable approaching element with filling fluid that may release filling fluid during a predefined period of time.

In other examples, the reduction in size of the approaching element may be defined or achieved by releasing material from the approaching element itself when the approaching element is formed of at least one bioresorbable material, i.e. when the approaching element comes in contact with the physiological lumen it begins to release material from its structure.

In other examples, the approaching element may be formed of at least one material having elastic properties. A stressed or stretched state of the approaching element may be defined when part of its contour or periphery is relatively and radially away from the longitudinal axis, and a resting state in which the contour or periphery is closer to the longitudinal axis. The holding portion may be placed on the tissue surrounding the fistulous orifice in a stretched state, and the approaching element may tend to close the fistulous orifice.

In a particular example, the approaching element may be formed by a combination of at least two materials with different degradation ratios, wherein a second element having a slower degradation ratio than a first element. The second element may have elastic or flexible properties, such that as the first element degrades and reduces its presence in the structure of the approaching element, the second element begins to exert some degree of tension on the wall of the physiological lumen adjacent to the fistulous orifice.

In some examples, the sealant device 100 may comprise an approaching inlet 24 arranged on the approaching element 20, wherein the approaching inlet 24 may be in fluid communication with the filling element 10. The latter can be seen in Figure 2. The approaching inlet 24 may be a kind of port suitable for receiving a catheter 40 or the like to fill the filling element 10. The feature of the approaching inlet 24 has been depicted with reference to Figure 1. However, the approaching inlet 24 may be present in other examples of the sealant device described in the present disclosure, although not depicted in the figures.

In some examples, the filling element 10 may comprise an inflatable filling balloon. This filling balloon may be a distal balloon. The inflatable filling balloon may be formed, at least, by a cover or the like. The cover may have a bag-like configuration.

When the filling element 10 comprises an inflatable filling balloon, the interior 50 of the filling balloon may be in fluid communication with the approaching inlet 24.

The sealant device 100 may comprise a filling duct 32 to fluidly communicate the approaching inlet 24 to the filling element 10, wherein at least a part of the filling duct 32 may be disposed along the connector 30. The connector 30 may have the filling duct 32 configured to conduct the filling fluid FF or to receive a catheter 40 or the like. The filling duct 32 may be pre-formed during manufacturing.

The feature of the filling duct 32 has been depicted with reference to Figure 1. However, the filling duct 32 may be present in other examples of the sealant device described in the present disclosure, although not depicted in other figures.

In examples, the approaching element 20 may comprise an inflatable approaching balloon. This filling balloon may a proximal balloon. The inflatable approaching balloon may be formed, at least, by a cover or the like. The cover may have a baglike configuration.

When the approaching element comprises an inflatable approaching balloon, the interior 60 of the approaching balloon 20 may be in fluid communication with the approaching inlet 24.

Although in the examples illustrated in this disclosure, the filling element 10 and/or the approaching element 20 is filled via the catheter through the approaching inlet 24, this is not an exclusive example. The filling element 10 and/or the approaching element 20 may be filled via a needle (not illustrated) passing through the outer sheath. In examples, the approaching element 20 may have a closing portion 26 to face, at least partially, the physiologic lumen PL. The approaching inlet 24 may be arranged on the closing portion 26 or any other location in the approaching element 20.

Figures 4 - 6 schematically illustrate the sealant device 100 of Figure 2 with a catheter 40 to seal a cavity C of a fistula. Figure 4 depicts the sealant device 100 being introduced into the fistula cavity C through the fistulous orifice FO. For this purpose the catheter 40 may be used as depicted. In these Figures 4 - 6 it can be seen that the sealant device 100 presents a retracted/compressed state or configuration in order to be able to move inside the endoscope. In Figure 5 it can be seen that the filling element 10 is in an expanded state due to being filled with filling fluid FF. In this example, the expanded filling element 10 contacts the inner side of the fistulous orifice FO. Arrows in the attached Figures indicate the filling fluid FF releasing from the sealant device.

The catheter 40 may have a catheter outlet 41 to at least partially fill the sealant device 100. Filling fluid FF may be injected from a proximal end of the endoscope relative to the practitioner. Although the example sealant device 100 of Figures 4 to 6 does not show the filling duct 32, it may also have a filling duct 32.

In Figure 6 the end of the catheter where the outlet 41 is located has been moved to the approaching element 20 to fill the interior 60 with filling fluid FF. According to this example, the filling element 10 may be filled first and then the approaching element 20 in case it is also refillable.

Figures 7 - 9 schematically illustrate a sealant device 200 according to an example with a catheter 10 to seal a cavity C of a fistula. In this example of the sealant device 200, the approaching element 21 comprises a disc-like holder. The approaching element 21 may have a body formed as a disc. Furthermore, in this example the approaching element 21 is not filled like the filling element 10. Apart from a discshaped disc, the approaching element 21 may adopt other shapes suitable to contact tissue adjacent to the fistulous orifice.

When the sealant device 200 of the example of Figure 7 is introduced into the fistula, the approaching element 21 may be compressed and/or folded so that it can be transported through the endoscope. When the approaching element 21 is detached from the catheter 40 it may adopt the deployed configuration of use as shown in Figure 9.

Figures 10 - 13 schematically illustrate a sealant device 300 according to a further example with a catheter 40 to seal a cavity C of a fistula. In this example, the filling balloon 11 and the approaching balloon 22 are cone-shaped and are arranged opposite to each other, such that the sealant device 300 has a diabolo or hourglass configuration.

In Figures 10 - 13, the filling duct 32 has a non-return valve 31. Furthermore, it can be seen that the approaching inlet 24 comprises a non-return valve 23. Non-return valves 31 and 23 may be arranged in any of the examples disclosed herein. Such valves may serve, among other things, to prevent fluid with which some part of the sealant device is filled from ending up elsewhere. For example, the filling fluid FF may be prevented from ending up in the approaching element 22. The non-return valve 23 may prevent or reduce unwanted leakage from the interior 60 of the approaching element 22.

In the example of Figures 10 - 13, the approaching element and/or the filling element have not been depicted in contact with the physiological lumen wall for the sake of clarity.

Depending on the shape, size or nature of the fistula, a particular example of the sealant device 100, 200, 300 may be chosen.

In an example, each of the filling element and the approaching element may be to be filled with different filling fluids FF from each other. The fluid to fill the approaching element may be the filling fluid FF as that one of the filling element.

In some examples, at least one of the filling element and the approaching element may be made from at least two biodegradable materials having different degradation rates.

An outer face of at least one the filling element and the approaching element may have a number of pores to release the fluid from the interior 50, 60. In examples, at least one of the filling element and the approaching element may comprise a porogenic substance. The porogenic substance may be removed, detached or eliminated in use to define pores in the elements. At least one of an outer face of the filling element and the holding portion may be texturized. This may help to improve the relative attachment of the tissue to the approaching element.

At least one of an outer face of the filling element and the holding portion may have a biocompatible adhesive. This may help to improve the relative attachment of the tissue to the approaching element.

Depending on the case, at least one of the filling element and the approaching element may be made from at least one biodegradable polymer. The biodegradable polymer may be made from at least one of polyester and polyurethane (PUR), or the combination thereof. The polyester may comprise at least one of Poly Glycerol Sebacate (PGS), Polycaprolactone (PCL) and Polylactic Acid (PLA), or the combination thereof.

In some examples, at least one of the filling element 10 and the approaching element 20 comprises a biological component. The biological component may comprise at least one of collagen, gelatin, fibroin, or a combination thereof.

In some examples, at least one of the filling element and the approaching element may be made from at least one biostable elastomer.

The connector 30 may be made from a material with flexible properties. The approaching element and the filling element may be brought closer together. This may improve the combined effect of the approaching element and the filling element in relation to the approach closure of the fistulous orifice.

Depending on the case, the filling fluid FF may have re-epithelializing properties. It may accelerate, enhance or assist the natural process of fistula occlusion. The filling fluid FF may comprise a hydrogel.

In any of the herein disclosed examples of the sealant device, the filling element 10, 11 may have a permeable cover to release at least a part of the filling fluid FF in the cavity C.

The approaching element 20, 21 , 22 may have a permeable cover to release at least a part of the filling fluid FF in the fistulous orifice and/or the tissue surrounding the fistulous orifice.

Degradation of the sealant device in use may be in the range of 4-10 weeks, more particularly 6-8 weeks. Gradual reduction of the size of the sealant device may be thus possible to allow the fistula to close at least partially. In the instance where some elements of the sealant device may release filling fluid, this fluid may be released within that time ranges to enhance fistula healing. This may avoid the presence of drains through catheters that exit through natural orifices (mouth I anus).

Figures 14 and 15 schematically illustrate sealant systems 500 according to some examples. These figures include the catheter 40 and a portion of the endoscope 70.

According to an aspect of the present disclosure, a sealant system 500 to seal a cavity C of a fistula is disclosed. The system 500 comprises: a sealant device 100, 200, 300 according to any of herein disclosed examples; and a catheter 40 to apply the sealant device to the fistula.

According to an example, the sealant system 500 may comprise an endoscope 70 having a channel 71 to receive the catheter and the sealant device. The channel 71 may be related to a gastroscope or a colonoscope.

The endoscope 70 may have a handle (not illustrated) in a proximal end to the practitioner. There may be Luer-lock connector in the handle. The Luer-lock may comprise infusion or withdrawal syringes to feed the filling fluid FF into the sealant device. Male and female Luer-lock is a standardized system of small-scale fluid fittings used for making leak-free connections between a male fitting and its mating female part on medical and laboratory devices.

When it comes to the digestive tract, the catheter 40 may be introduced into the patient's body through the mouth or anus (not shown) in order to access the digestive tract. The catheter 3 may be advanced to the area of the digestive tract where the fistula is supposed to be located. This area may be referred as a target site. The distal side 43 of the catheter is intended to be the first part to be introduced into the patient's body and is the part of the catheter 40 that is intended to be closest to the fistula to be occluded. The catheter 40 may carry the sealant device 100, 200, 300 in a compressed, retracted, or non-expanded state, see for instance Figures 4 and 7.

In one example the catheter may be approximately 200 cm long. This length may be considered relatively long. In one example, the catheter may have a diameter of approximately 2.8 - 3.4 mm. This may be considered a relatively thin diameter.

With such dimensions the catheter 40 may be employed through a working channel 71 of the endoscope 70 and moved through the digestive tract to any point in the digestive tract.

In some examples, the sealant device has a width compatible with the diameter of the catheter 40 in a compressed state.

The catheter 40 may be made of a suitable material or may have a configuration that allows it to adapt to the shape of the digestive tract. At least the material of the catheter 40 intended to be in contact with the digestive tract may be biocompatible.

In the following examples of the operation of the sealant devices will be described regarding a method for sealing a cavity of a fistula. The examples will be disclosed related to the Figures 16 and 17. Figure 16 schematically illustrates some views of the actuation of the sealant device in a cavity of a physiological lumen according to an example. Figure 17 is a block diagram of an example of a method of the present disclosure.

According to an aspect of the present disclosure a method 400 for sealing a cavity of a fistula is disclosed. The fistula having a bottom and a fistulous orifice on a wall of a physiologic lumen. The method 400 comprises: providing 410 a sealant device 100, 200, 300 according to any of herein disclosed examples in the cavity C using an endoscopic catheter 40. The practitioner may introduce the sealant device via the catheter 40 down or up the digestive tract until the location of the fistula is reached. Once there, he or she may maneuver to insert the distal end 42 with the sealant device into the cavity C. The sealant device may be moved into the cavity in a retracted or unexpanded state; filling 420 the filling element 10, 11 with filling fluid FF to expand the filling element. Once introduced into the cavity C, the practitioner may actuate a syringe arranged on the handle of the endoscope containing the filling fluid. This may cause the filling fluid to flow out of the outlet 41 of the catheter 40 and begin to fill at least one element of the sealant device. As the sealing fluid FF is introduced into the sealant device, it may expand the sealant device; contacting 430, at least, a portion of the cavity with the filling element. As the filling element is filled with the filling fluid, the filling element may contact more and more of the cavity surface. In some cases, the filling element may contact the bottom of the cavity or the fistulous orifice. As the filling element fills, it may approach the inner side of the fistulous orifice, i.e. the side opposite the physiological lumen wall.

In examples, the inner side of the fistulous orifice may be the portion of the cavity that the filling element contacts in an expanded state.

The amount of filling fluid introduced may remain inside the filling element and does not spill outside the fistula. The filling element may be filled until a maximum inflation state or point of no return where the filled filling element may be hold to the walls of the fistulous cavity. In examples, the practitioner may move the catheter into the lumen of the digestive tract so that the filling element may contact the fistulous orifice on a side opposite the side of physiological lumen. Once the filling element has been filled to the desired volume, the practitioner may disconnect the filling element from the catheter. The connector 30 may be positioned in the fistulous pathway, i.e. through the fistulous orifice; placing 440 the holding portion of the approaching element onto a part of a wall tissue adjacent to the fistulous orifice, such that the adjacent wall tissue is held in a predefined position relative to a longitudinal axis of the sealant device. The practitioner may maneuver the endoscope to place the approaching element over the fistulous orifice. This way, the fistulous orifice may be occluded.

Prior to placing the holding portion of the approaching element, the practitioner may have moved the tissue adjacent to the fistulous orifice toward the longitudinal axis of the sealant device. The adjacent tissue may be placed in a predetermined position to be fixed with the approaching element.

In some examples, the method 400 may comprise approaching part of a wall tissue adjacent to the fistulous orifice with respect to the longitudinal axis of the sealant device, before placing the holding portion.

In some examples, the method 400 may comprise filling the approaching element with filling fluid. The approaching element may be filled, for example, until the approaching element reaches a sufficient size to completely occlude the fistulous orifice.

Once the approaching element has been filled to the desired volume, the practitioner may disconnect the approaching element from the catheter.

In some examples, the method 400 may comprise filling each of the filling element and the approaching element with different filling fluids from each other.

In some examples of the method 400, the physiologic lumen may belong to the digestive tract.

In some examples of the method 400, the fistula may be a non-vascular fistula.

In some examples, the method 400 may comprise contacting, at least partially, a portion of the fistulous orifice with the filling element in an expanded state.

Figure 16 shows an example of the evolution of the sealant device in use at four different time points. Starting from the left, a sealant device can be seen that has been separated from the catheter 40. The filled filling element 10 has approached the inner side of the fistulous orifice and the approaching element occludes the fistulous orifice at least on the outer side of the fistulous orifice. In the next illustration, the filling fluid FF is seen to be released from the filling element 10. In this example the filling element has not initially contacted the bottom of the fistulous cavity. In the third illustration, the size of the fistula and the sealing element have been substantially reduced. The filling element has been releasing filling fluid into the cavity C which has been reduced by the growth of tissue in the patient's body. Finally, the physiological lumen free of fistula and sealant device can be seen. Between the first and the last representation, there may be from 8 to 10 weeks.

In the present disclosure, it is understood that the fistular orifice may have an average diameter of 5 mm. Although this figure may vary.

For reasons of completeness, various aspects of the present disclosure are set out in the following numbered clauses:

Clause 1. A sealant device to seal a cavity of a fistula, the fistula having a fistulous orifice on a wall of a physiologic lumen, the sealant device comprising: a filling element to be filled with a filling fluid to contact, at least, a portion of the cavity in an expanded state; an approaching element having a holding portion to contact at least a part of a wall tissue adjacent to the fistulous orifice, such that the adjacent wall tissue is held in a predefined position relative to a longitudinal axis of the sealant device in the expanded state; a connector to connect the filling element with the approaching element.

Clause 2. The sealant device according to clause 1 , comprising an approaching inlet arranged on the approaching element, wherein the approaching inlet is in fluid communication with the filling element.

Clause 3. The sealant device according to any of clauses 1 - 2, wherein the filling element comprises an inflatable filling balloon.

Clause 4. The sealant device according to any of clauses 1 - 3, wherein the approaching element comprises an inflatable approaching balloon.

Clause 5. The sealant device according to clauses 3 and 4, wherein the filling balloon and the approaching balloon are cone-shaped and are arranged opposite to each other, such that the sealant device has a diabolo or hourglass configuration.

Clause 6. The sealant device according to clauses 3 and 4, wherein each of the filling element and the approaching element are to be filled with different filling fluids from each other.

Clause 7. The sealant device according to clause 2, comprising a filling duct to fluidly communicate the approaching inlet to the filling element, wherein at least a part of the filling duct is disposed along the connector.

Clause 8. The sealant device according to clause 7, wherein the filling duct has a non-return valve.

Clause 9. The sealant device according to clause 1, wherein the approaching element comprises a disc-like holder. Clause 10. The sealant device according to any of clauses 1 - 9, wherein at least one of the filling element and the approaching element is made from at least two biodegradable materials having different degradation rates.

Clause 11. The sealant device according to any of clauses 3 and 4, wherein an outer face of at least one the filling element and the approaching element has a number of pores to release the filling fluid from the interior.

Clause 12. The sealant device according to any of clauses 1 - 11, wherein at least one of an outer face of the filling element and the holding portion is texturized.

Clause 13. The sealant device according to any of clauses 1 - 12, wherein at least one of an outer face of the filling element and the holding portion has a biocompatible adhesive.

Clause 14. The sealant device according to any of clauses 1 - 13, wherein the fistula is a non-vascular fistula, more particularly the fistula is a gastrointestinal fistula.

Clause 15. The sealant device according to any of clauses 1 - 14, wherein the filling element has a permeable cover to release at least a part of the filling fluid in the cavity.

Although only a number of examples have been disclosed herein, other alternatives, modifications, uses and/or equivalents thereof are possible. Furthermore, all possible combinations of the described examples are also covered. Thus, the scope of the present disclosure should not be limited by particular examples, but should be determined only by a fair reading of the claims that follow. If reference signs related to drawings are placed in parentheses in a claim, they are solely for attempting to increase the intelligibility of the claim, and shall not be construed as limiting the scope of the claim.

Claims

1. A sealant device to seal a cavity of a fistula, the fistula having a fistulous orifice on a wall of a physiologic lumen, the sealant device comprising: a filling element to be filled with a filling fluid to contact, at least, a portion of the cavity in an expanded state; an approaching element having a holding portion to contact at least a part of a wall tissue adjacent to the fistulous orifice, such that the adjacent wall tissue is held in a predefined position relative to a longitudinal axis of the sealant device in the expanded state; a connector to connect the filling element with the approaching element.

2. The sealant device according to claim 1 , comprising an approaching inlet arranged on the approaching element, wherein the approaching inlet is in fluid communication with the filling element.

3. The sealant device according to any of claims 1 - 2, wherein the filling element comprises an inflatable filling balloon.

4. The sealant device according to claims 2 and 3, wherein the interior of the filling balloon is in fluid communication with the approaching inlet.

5. The sealant device according to any of claims 1 - 4, wherein the approaching element comprises an inflatable approaching balloon.

6. The sealant device according to claims 2 and 5, wherein the interior of the approaching balloon is in fluid communication with the approaching inlet.

7. The sealant device according to any of claims 1 - 6, wherein the approaching element has a closing portion to face, at least partially, the physiologic lumen.

8. The sealant device according to claims 2 and 7, wherein the approaching inlet is arranged on the closing portion.

9. The sealant device according to claims 3 and 5, wherein the filling balloon and the approaching balloon are cone-shaped and are arranged opposite to each other, such that the sealant device has a diabolo or hourglass configuration.

10. The sealant device according to claims 3 and 5, wherein each of the filling element and the approaching element are to be filled with different filling fluids from each other.

11. The sealant device according to claim 2, comprising a filling duct to fluidly communicate the approaching inlet to the filling element, wherein at least a part of the filling duct is disposed along the connector.

12. The sealant device according to claim 11, wherein the filling duct has a non-return valve.

13. The sealant device according to claim 1, wherein the approaching element comprises a disc-like holder.

14. The sealant device according to claim 2, wherein the approaching inlet comprises a non-return valve.

15. The sealant device according to any of claims 1 - 14, wherein at least one of the filling element and the approaching element is made from at least two biodegradable materials having different degradation rates.

16. The sealant device according to any of claims 3 and 5, wherein an outer face of at least one the filling element and the approaching element has a number of pores to release the filling fluid from the interior.

17. The sealant device according to claim 16, wherein at least one of the filling element and the approaching element comprises a porogenic substance.

18. The sealant device according to any of claims 1 - 17, wherein at least one of an outer face of the filling element and the holding portion is texturized.

19. The sealant device according to any of claims 1 - 18, wherein at least one of an outer face of the filling element and the holding portion has a biocompatible adhesive.

20. The sealant device according to any of claims 1 - 19, wherein at least one of the filling element and the approaching element is made from at least one biodegradable polymer.

21. The sealant device according to claim 20, wherein the biodegradable polymer is made from at least one of polyester and polyurethane (PUR), or the combination thereof.

22. The sealant device according to claim 21, wherein the polyester comprises at least one of Poly Glycerol Sebacate (PGS), Polycaprolactone (PCL) and Polylactic Acid (PLA), or the combination thereof.

23. The sealant device according to any of claims 1 - 22, wherein at least one of the filling element and the approaching element comprises a biological component.

24. The sealant device according to claim 23, wherein the biological component comprises at least one peptide-based component, such as collagen, gelatin, fibroin, or a combination thereof.

25. The sealant device according to claim 1 , wherein at least one of the filling element and the approaching element is made from at least one biostable elastomer.

26. The sealant device according to any of claims 1 - 25, wherein the filling fluid has re-epithelializing properties.

27. The sealant device according to any of claims 1 - 26, wherein the filling fluid comprises a hydrogel.

28. The sealant device according to any of claims 1 - 27, wherein the fistula is a gastrointestinal fistula.

29. The sealant device according to any of claims 1 - 28, wherein the fistula is a non- vascular fistula.

30. The sealant device according to any of claims 1 - 29, wherein the physiologic lumen is non-vascular.

31. The sealant device according to any of claims 1 - 30, wherein the filling element has a permeable cover to release at least a part of the filling fluid in the cavity.

32. The sealant device according to any of claims 1 - 31 , wherein the connector is made from a material with flexible properties.

33. The sealant device according to any of claims 1 - 32, wherein the approaching element is able of or configured to reduce in size from a first or predefined size to a size or second size smaller than the first or predefined size, wherein the reduction in size occurs at least relative to the longitudinal axis LA of the sealant device.

34. A method for sealing a cavity of a fistula, the fistula having a fistulous orifice on a wall of a physiologic lumen, the method comprising: providing a sealant device according to any of herein disclosed examples in the cavity using an endoscopic catheter; filling the filling element with filling fluid to expand the filling element in an expanded state; contacting, at least, a portion of the cavity with the filling element; placing the holding portion of the approaching element onto a part of a wall tissue adjacent to the fistulous orifice, such that the adjacent wall tissue is held in a predefined position relative to a longitudinal axis of the sealant device.

35. The method according to claim 34, comprising: approaching part of a wall tissue adjacent to the fistulous orifice with respect to the longitudinal axis of the sealant device, before placing the holding portion.

36. The method according to any of claims 34 - 35, comprising: filling the approaching element with filling fluid.

37. The method according to any of claims 34 - 36, comprising: filling each of the filling element and the approaching element with different filling fluids from each other.

38. The method according to any of claims 34 - 37, wherein the physiologic lumen belongs to the digestive tract.

39. The method according to any of claims 34 - 37, wherein the fistula is a non- vascular fistula.

40. The method according to any of claims 34 - 39, comprising: contacting, at least partially, a portion of the fistulous orifice with the filling element in an expanded state.

41. A sealant system to seal a cavity of a fistula, comprising: a sealant device according to any of herein disclosed examples; and a catheter to apply the sealant device to the fistula.

42. The sealant system according to claim 41, comprising: an endoscope having a channel to receive the catheter and the sealant device.