Air-tight endocavitary aspiration device for cardiac chamber surgery

Abstract

The present invention refers to a device and an air-tight endocavitary aspiration system, for cardiac chamber surgery, as well as to a method aimed at the elimination of gaseous micro-embolic activity, hemolysis and CO2 aspiration. The system advantageously allows to be able to combine cardiac chamber surgery with a minimally invasive extracorporeal circulation circuit.

Description

[0001] AIR-TIGHT ENDOCAVITARY ASPIRATION DEVICE FOR CARDIAC CHAMBER SURGERY

[0002] FIELD OF THE INVENTION

[0003] The present invention refers to a device and an air-tight endocavitary aspiration system, for cardiac chamber surgery, as well as to a method aimed at the elimination of gaseous micro-embolic activity, hemolysis and CO2aspiration. The system advantageously allows to be able to combine cardiac chamber surgery with a minimally invasive extracorporeal circulation circuit.

[0004] STATE OF THE ART

[0005] The management of bleeding, particularly originating from the pulmonary veins in the left sections of the heart, involves in heart surgery, and particularly in mitral valve surgery, the use of aspirators that tend to aspirate the blood once it has come into contact with the air.

[0006] The endocavitary aspiration of air mixed with blood often requires high negative pressures of aspiration to render the surgical field bloodless. Therefore, when using filters and open-air extracorporeal circulation systems, this phenomenon causes the production of gaseous micro-emboli, hemolysis, activation of inflammation and alteration of coagulation. This aspiration strategy cannot avoid the use of open extracorporeal circuits that have a greater physiopathological impact on hemodilution, hemolysis and inflammation than closed minimally invasive extracorporeal circulation systems.

[0007] Although considerable progress has been made in standardizing the surgical technique, some limitations remain to be overcome in the context of endovascular aspiration for the combination of minimal invasive extracorporeal circulation (MiECC) with minimally invasive mitral valve surgery (Ml MVS). In peri-operative practice and in scientific evidence, a suction cup is placed in the left pulmonary veins to keep the surgical field clean and carbon dioxide is insufflated into the thoracic cavity to displace the air. The aspirator is essential for a good view and a clear surgical field; however, the aspiration of the pulmonary vein involves a fair amount of aspiration of air mixed with blood. This principle presents particular difficulties in pressure control and the suction efficiency typical of MiECC management, and can cause the onset of gaseous micro-emboli, hemolysis, activation of inflammation and alteration of coagulation.

[0008] The gold standard in mitral valve surgery, in both conventional (sternotomy) and minimally invasive (minithoracotomy or thoracoscopy) approaches, involves the use of a suction device called a SUMP, which aspirates blood mixed with air from the pulmonary veins in a whirling and disorganized way (increasing hemolysis and the generation and transport of gaseous micro-embolic activity). The aspiration of CO2 from the surgical field also compromises the Vco2 parameter in the metabolic monitoring of extracorporeal circulation, which is monitored to prevent acute renal damage.

[0009] Therefore, the problem of providing an endocavity suction device that eliminates the airblood contact and the physiopathological alterations of the conventional closed systems of extracorporeal circulation remains in the state-of-the-art technology.

[0010] SUMMARY OF THE INVENTION

[0011] The Authors of the present invention have developed a new device for endovascular aspiration (1) and a system that comprises it (11), which, through the inflation of at least one perforated balloon (6) inside a venous lumen, completely occludes the venous lumen and allows the passage of blood towards a hollow tubular suction element (8) through the holes in the balloon.

[0012] Advantageously compared to existing devices, the device comprises a hollow tubular element with an elongated helical shape (5) configured to aspirate fluids during surgery, in which the helical structure allows the management of the laminar flow of the aspiration fluid and minimizes turbulence. This allows the excess negative pressure (or vacuum) upstream of the device (1) to be controlled, thus avoiding the collapse of the venous lumen wall around the balloon when anchored to the pulmonary venous lumen, which could hinder the aspiration of venous blood.

[0013] Furthermore, compared to the sump aspirator (gold standard) or the spring aspirator, the advantage of isolating the pulmonary veins with a bleeding rate through the inflation of the polyurethane balloon eliminates the vortex regime mixed with air and CO2, allowing a reduction in micro-embolic activity, hemolysis, and the aspiration of the CO2 administered in the surgical field in the extracorporeal circuit

[0014] The object of the present invention is therefore: a device for endocavitary aspiration (1) comprising:

[0015] - a first flexible tubular element (2) of elongated shape having a distal end (3) and a proximal end (4), wherein said proximal end (4) is closed and includes a plurality of holes,

[0016] - a hollow tubular element with an elongated helical shape (5) connected to said distal end (4) of said first tubular element (2), configured so as to allow suction,

[0017] - at least one perforated inflatable balloon (6), - at least one flexible hollow tubular element of elongated shape (9) passing through at least one of said plurality of holes in said proximal end (4) through said first element (2), connected to said balloon to allow its inflation or deflation by introduction of a fluid,

[0018] - at least one flexible hollow tubular element of elongated shape (7) passing through at least one of said plurality of holes in said proximal end (4) through said first element (2), connected to said balloon and to a hollow tubular suction element (8) passing through said first element (2), configured to allow suction, wherein said inflatable balloon (6), when placed inside a venous lumen, and inflated, completely occludes the venous lumen and allows the passage of blood towards said hollow tubular suction element (8) through the holes on said balloon;

[0019] A system for endocavitary aspiration (11) comprising a device (1) according to any one of the embodiments herein described, a device for controlling and / or managing the filling and internal pressure of the balloon (12), and a device for extracorporeal circulation and a vacuum generating device to allow aspiration.

[0020] Other advantages and features of the present invention will be apparent from the detailed description.

[0021] DETAILED DESCRIPTION OF FIGURES

[0022] Fig. 1. Schematic representation of the aspiration device according to a preferred embodiment of the present invention.

[0023] Fig, 2. Schematic representation of the aspiration device according to a preferred embodiment of the present invention.

[0024] Fig, 3. Representation of the method of using the device according to a preferred embodiment of the present invention.

[0025] GLOSSARY

[0026] In the present invention, the term “endocavitary aspiration device” refers to a medical instrument used to aspirate fluids or tissues from internal cavities of the human body, such as the aspiration of secretions or liquids from hollow organs during medical procedures. In the medical context, endocavitary aspiration can be performed for several purposes, including the drainage of accumulated fluids, the removal of blood or pus from a cavity, or the collection of samples for diagnostic analysis.

[0027] In the present invention, the term “cannula” refers to a thin, hollow tube used in the medical field for various purposes, such as inserting or withdrawing fluids from the element. Cannulas can be made of different materials such as plastic or metal and are designed with various sizes and shapes depending on the specific purpose for which they are to be used. The cannulas are used to draw fluids from a cavity in the element or to drain accumulations of liquids, for example in the suction of air or liquid from a surgical area. During some surgical procedures, the cannulas can also be used to position drainage tubes or to access specific areas of the element.

[0028] In the present invention, the term “roller pump for endocavitary aspiration” refers to a pump that uses a roller mechanism to generate the vacuum necessary for endocavitary aspiration.

[0029] In the present invention, with the term “extracorporeal circulation techniques” reference is made to a process in which the blood is temporarily diverted from the body through a system of pumps and oxygenated by a blood oxygenation unit (such as a membrane oxygenator). In conventional techniques, the roller pump is used to manage the aspiration during the extracorporeal circulation process.

[0030] In the present invention, the term “Venturi devices" refers to devices that exploit Bernoulli's principle to generate a vacuum or negative pressure in a fluidic system. Bernoulli's principle states that in a moving fluid, if the velocity of the fluid increases, its pressure decreases, and vice versa. The Venturi effect is based on this relationship between fluid speed and pressure. The Venturi device is composed of a section of pipe with a narrowing followed by a widening. When a fluid flows through the narrowed section, its speed increases, generating a lower pressure zone. When the fluid crosses the widened section, its speed decreases and the pressure is restored. This variation in pressure can be exploited to suck or push fluids depending on the context of use. In devices with a Venturi effect in venous return, the vacuum could be created by using a device that exploits the Venturi principle to suck blood or other fluids from the venous system.

[0031] In the present invention, a “negative pressure centrifugal pump” refers to a device that uses centrifugal force to push fluid through the system. Negative pressure indicates that a vacuum could be generated in the venous line thanks to the negative pressure effect created by the centrifugal pump.

[0032] The size “20 Fr” refers to the gauge of a cannula. In the medical field, the term “Fr” (French) is a unit of measurement for the size of catheters and cannulas. One French corresponds to 1 / 3 of a millimetre. Therefore, a 20 Fr cannula has a diameter of about 6.7 millimetres (20 Fr x 1 / 3 mm / Fr). DETAILED DESCRIPTION

[0033] In order to facilitate understanding of the present invention, reference will be made below to the preferred embodiments illustrated in the figures and to the terms used for their description.

[0034] With reference to Figure 1 , a device for endocavitary aspiration (1) comprising a first flexible tubular element of elongated shape (2) having a distal end (3) and a proximal end (4) is reported, in which said proximal end (4) is closed and comprises a plurality of holes (not shown in the figure). This element can also be defined as a cannula. The device (1) also comprises a hollow tubular element with an elongated helical shape (5) connected to said distal end (4) of said first tubular element (2), configured so as to allow suction, and four perforated inflatable balloons (6a, 6b, 6c and 6d), each connected by means of a flexible hollow tubular element of elongated shape (9a, 9b, 9c and 9d), passing through four holes in said proximal end (4) through said first element (2), or also defined as a suction line, allowing inflation or deflation by the introduction of a fluid. The device also comprises four flexible hollow tubular elements of elongated shape (7a, 7b, 7c, 7d), passing through four holes of said plurality of holes in said proximal end (4) and through said first element (2), and connecting each respective balloon (6a, 6b, 6c and 6d) to a hollow tubular suction element (8), which also passes through said first element (2). The elements 7a, 7b, 7c and 7d, and the element 8 are configured in such a way as to allow suction, i.e. they comprise means for being connected to an instrument for producing a vacuum or negative pressures. The element 8 can also be defined as a central suction line. In the described embodiment, elements 7a, 7b, 7c and 7d are configured such that, during surgery, the blood coming from the venous lumens into which balloons 6a, 6b, 6c and 6d are inserted passes through the holes of the balloons and is conveyed into the central suction line (8). The flexible hollow tubular elements of elongated shape (9a, 9b, 9c and 9d) pass through the central suction lumen (8) and inside the respective elements 7a, 7b, 7c and 7d, allowing each balloon to be selectively inflated according to its color code.

[0035] With reference to Figure 2, a system (11) for endocavitary aspiration is represented, comprising a device (1) as already illustrated for the description of Figure 1, in which the device (1) is connected by means of four tubular elements (9a, 9b, 9c and 9d, also identified here as filling lines) to a device for controlling and / or managing the filling and internal pressure of the balloon (12), including a screen (13) for the control and / or management of the balloon filling pressure 6a, 6b, 6c and 6d through the filling lines (9a, 9b, 9c and 9d), hardware for filling with the fluid (14), and a fluid storage device (15). In the embodiment where the fluid is helium, the storage device (15) is a helium cylinder. The central suction line (8) is configured to be connected to an extracorporeal circulation device, and to a vacuum generation device to allow aspiration.

[0036] With reference to Figure 3, a method of using a preferred embodiment of the invention is represented, in which there are four inflated and perforated balloons, each characterized by a different color, placed inside each pulmonary vein (upper right, upper left, lower right, lower left), with the device (1) introduced inside the left atrium during cardiac surgery.

[0037] The present invention refers to a device for endocavitary aspiration (1) comprising:

[0038] - a first flexible tubular element (2) of elongated shape having a distal end (3) and a proximal end (4), wherein said proximal end (4) is closed and includes a plurality of holes,

[0039] - a hollow tubular element with an elongated helical shape (5) connected to said distal end (4) of said first tubular element (2), configured so as to allow suction,

[0040] - at least one perforated inflatable balloon (6),

[0041] - at least one flexible hollow tubular element of elongated shape (9) passing through at least one of said plurality of holes in said proximal end (4) through said first element (2), connected to said balloon to allow its inflation or deflation by introduction of a fluid,

[0042] - at least one flexible hollow tubular element of elongated shape (7) passing through at least one of said plurality of holes in said proximal end (4) through said first element (2), connected to said balloon and to a hollow tubular suction element (8) passing through said first element (2), configured to allow suction, wherein said inflatable balloon (6), when placed inside a venous lumen, and inflated, completely occludes the venous lumen and allows the passage of blood towards said hollow tubular suction element (8) through the holes on said balloon.

[0043] In a preferred embodiment, said venous lumen is a pulmonary vein, preferably the right upper, left upper, right lower or left lower pulmonary vein.

[0044] Said first flexible tubular element of elongated shape (2) can also be identified as a central cannula.

[0045] Said hollow tubular element with elongated helical shape (5) is configured so as to allow suction, i.e. it is configured so as to allow connection with a vacuum generating element. A vacuum generating element is for example a roller pump for endo-cavity suction, used in conventional extracorporeal circulation techniques, Venturi effect devices in venous return, or in series in the venous line under negative pressure of the centrifugal pump.

[0046] The helical structure allows the management of the laminar flow of the suction fluid minimizes turbulence. This allows to control the excess negative pressure (or vacuum) upstream of the device (1), thus avoiding the collapse of the venous lumen wall around the balloon when anchored to the pulmonary venous lumen, which could hinder the aspiration of venous blood. In other words, element (5) can also be defined as a helical suction line.

[0047] In one embodiment, said hollow tubular element (9), also referred to herein as filling line (9), passes through the interior of said suction hollow tubular element (8) and said flexible hollow tubular element of elongated shape (7), connecting to said balloon (6).

[0048] The hollow suction tube (8), connected by means of the flexible hollow tubular element of elongated shape (7) passing through at least one of the said plurality of holes in the said proximal end (4) through the said first element (2), to the said balloon is, in other words, an element in which, during the operative phase, the blood passing through the holes of the balloon (6) and said element (7) is channeled. In one embodiment, when there is a plurality of balloons (6), the flexible hollow tubular elements of elongated shape

[0049] (7) will also be the same number as the balloons, and the blood passing through each balloon (6) and each flexible hollow tubular element of elongated shape (7) will be conveyed in the single line (8). In one embodiment, said hollow tubular suction element

[0050] (8) is configured so that it can be connected to a device for creating a vacuum or negative pressure. In a preferred embodiment, said vacuum-creating device is a roller pump or a vacuum pump assisted in conventional extracorporeal circulation, in minimally invasive circulation, it will connect to the venous return that is affected by the negative pressure of the thruster.

[0051] In one embodiment, the device (1) is a disposable device.

[0052] In one embodiment, said flexible hollow tubular element of elongated shape (9) passes through said distal end (3) and is configured for the connection to a fluid dispenser. In other words, said member (9) can be defined as a fill line.

[0053] In a preferred embodiment, said fluid is helium, CO2, or physiological solution. In a particularly preferred embodiment, this fluid is helium. The use of helium is particularly advantageous since it is a gas with a low embolic profile, and it has a density that is easy to monitor in terms of pressures and any leaks resulting from the system used, and it thus allows the use of a closed system and reduces fluid waste.

[0054] In one embodiment, said element (7) connected to said balloon (6) and to a hollow tubular suction element (8) passing through said first element (2) is configured to be connected to an extracorporeal circulation machine.

[0055] Extracorporeal circulation is a technique that allows the temporary replacement of the heart and lungs with a machine that replaces their functions, allowing to isolate the heart from the circulation and thus to perform ‘open heart’ surgery on the bloodless cardiac chambers. In extracorporeal circulation, or heart-lung machine, venous blood is taken from the venae cavae or directly from the right atrium, it passes into a device called oxygenator, where the venous blood is oxygenated by exposure to a flow of oxygen, and is then pumped into the patient's arterial system. The circuit is completed with a heat exchanger and with pumps that aspirate the residual blood from the surgical field. There is also a myocardial perfusion system to keep the heart alive during the operation, during which it is not perfused physiologically with oxygenated blood through the coronary arteries.

[0056] In one embodiment, the number of balloons (6) is a plurality (6a, 6b, 6c, 6d), preferably at least 2, 3 or 4. The assembly of one or more balloons (6) to the suction line (8) inside the first element (2) can be set up before or during surgery, depending on the number of balloons (6) that are desired to be anchored to the pulmonary veins. In particular, the blood entering the holes of the balloons (6) is conveyed into the suction line (8). This allows the operator to choose to selectively anchor one or more balloons (6) in relation to the visual bleeding, and therefore in relation to the severity of the venous return in the pulmonary veins.

[0057] In one embodiment, said balloon (6) has an elliptical shape.

[0058] In a further embodiment, said balloon (6) has a maximum filling volume of 1 to 10 ml, preferably 5 ml. This volume allows to obtain, when inflated and placed in a venous lumen, a maximum pressure of 150 to 180 mmHg. This pressure favorably determines an air-tight seal of the blood inside the venous lumen, providing in addition to aspiration also physical isolation of the bleeding, favoring the visualization of the surgical field.

[0059] In one embodiment, said balloon (6), and / or said element (7) connected to said balloon (6) and to a hollow tubular suction element (8) passing through said first element (2) is made of a polymeric material, preferably polyurethane. Polyurethane is a material that is highly resistant to high pressures, and has high biocompatibility and sustainability, and is therefore advantageous for use in the device of the invention.

[0060] This pressure favorably determines an air-tight seal of the blood inside the venous lumen, providing besides aspiration also physical isolation of the bleeding, favoring the visualization of the surgical field

[0061] In one embodiment, said balloon (6) comprises three medial holes and one central hole. The configuration of the holes on the balloon facilitates blood aspiration. However, it is possible to use a different number and arrangement of holes on the balloons, as known to the skilled person. In particular, it is preferable that the number and arrangement of the holes allow for a homogeneous management of blood suction throughout the lumen. In one embodiment, said balloon (6) and said flexible hollow element of elongated shape (9) connected to said balloon to allow its inflation and deflation by the introduction of a fluid, are identified by a color code. By ‘color code’, it is meant a visual identification system in which a color is assigned to each balloon (6) and the element connected to it

[0062] (9) for inflating or deflating the balloon (6), for example red, green, yellow and purple, which allows it to be recognized with respect to the other balloons (6) and the other inflation / deflation lines (9). To allow for proper identification, each balloon will be assigned a different color, and each inflation / deflation line will be assigned the same color as the balloon to which it is connected.

[0063] In a preferred embodiment, the fluid dispensing device, and in particular for the administration of helium and the monitoring of pressures, comprises a helium cylinder, a management monitor, and a hardware system that dispenses helium in a closed circuit into the balloons (6) according to the color codes requested by the surgeon for their positioning.

[0064] In a preferred embodiment, said element (7) connected to said balloon (6) and to a hollow tubular suction element (8) passing through said first element (2) comprises an internal metallic shape memory structure. The use of an internal shape-memory metal structure allows the optimization of the space during use of the device (1), to select one or more balloons (6) to be inserted into the pulmonary venous lumen, avoiding the use of syringes with physiological solution which are bulky. Materials that can be used for a shapememory metal structure include shape-memory alloys (SMA), for example nitinol.

[0065] In one embodiment, said element (7) connected to said balloon (6) and to a hollow tubular suction element (8) passing through said first element (2) has a diameter of approximately 0.3 mm to approximately 3.3 mm, preferably approximately 1.67 mm. Using French (Fr) as a unit of measurement, the size of said element (7) ranges from 1 to 10 Fr, preferably 5 Fr.

[0066] In a preferred embodiment, said first flexible tubular element (2) has a diameter of about 3.3 to about 10 mm, preferably about 6.7 mm. Using French (Fr) as a unit of measure, the size of said element (2) ranges from 10 Fr to 30 Fr, preferably 20 Fr.

[0067] In one embodiment, the device (1) comprises inside the first element (2) a fixing system

[0068] (10) for fixing the internal elements to said first element (2). For example, said fixing system (10) consists of a wall inside the element (2) with holes through which the elements pass through the element (2).

[0069] Advantageously, the device (1) can be introduced into the body of a subject through the use of a conventional trocar. A trocar is a dedicated introducer device in the context of minimally invasive and thoracoscopic surgery.

[0070] Further object of the present invention is a system for endocavitary aspiration comprising a device for endocavitary aspiration (1) comprising: - a first flexible tubular element (2) of elongated shape having a distal end (3) and a proximal end (4), wherein said proximal end (4) is closed and includes a plurality of holes,

[0071] - a hollow tubular element with an elongated helical shape (5) connected to said distal end (4) of said first tubular element (2), configured so as to allow suction,

[0072] - at least one perforated inflatable balloon (6),

[0073] - at least one flexible hollow tubular element of elongated shape (9) passing through at least one of said plurality of holes in said proximal end (4) through said first element (2), connected to said balloon to allow its inflation or deflation by introduction of a fluid,

[0074] - at least one flexible hollow tubular element of elongated shape (7) passing through at least one of said plurality of holes in said proximal end (4) through said first element (2), connected to said balloon and to a hollow tubular suction element (8) passing through said first element (2), configured to allow suction, wherein said inflatable balloon (6), when placed inside a venous lumen, and inflated, completely occludes the venous lumen and allows the passage of blood towards said hollow tubular suction element (8) through the holes on said balloon,

[0075] - a device for controlling and / or managing the filling and internal pressure of the balloon (12),

[0076] - a device for extracorporeal circulation and / or a vacuum generating device to allow aspiration.

[0077] The system of the present invention is particularly advantageous since it allows to associate with cardiac chamber surgery a minimally invasive extracorporeal circulation circuit. Furthermore, the system, during surgery, allows, by inflating the balloon (6), the venous lumen to be completely occluded, preventing air from becoming trapped in the suction line, allowing the use of minimally invasive extracorporeal circulation techniques in mitral valve surgery, eliminating air-blood contact and consequently eliminating the physiopathological alterations of conventional circuits, such as gaseous micro-emboli, hemolysis, activation of inflammation and alteration of coagulation.

[0078] In a preferred embodiment, said venous lumen is a pulmonary vein, preferably the right superior, left superior, right inferior, or left inferior pulmonary vein.

[0079] Said first flexible tubular member of elongated shape (2) may also be identified as a central cannula.

[0080] This hollow tubular element with an elongated helical shape (5) is configured so as to allow aspiration, i.e. it is configured so as to allow connection with a vacuum generating element. A vacuum generating element is for example a roller pump for endocavitary suction, used in conventional extracorporeal circulation techniques, Venturi effect devices in venous return, or in series in the venous line under negative pressure of the centrifugal pump. The helical structure allows the management of the laminar flow of the suction fluid and minimizes turbulence. This allows to control the excess of negative pressure (or vacuum) upstream of the device (1), thus avoiding the collapse of the venous lumen wall around the balloon when anchored to the pulmonary venous lumen, which could hinder the aspiration of venous blood. In other words, the element (5) can also be defined as a helical suction line.

[0081] In one embodiment, said hollow tubular element (9), also referred to herein as a filling line (9), passes through the interior of said suction hollow tubular element (8) and said flexible hollow tubular element of elongated shape (7), connecting to said balloon (6).

[0082] The hollow tubular suction element (8), connected by means of the flexible hollow tubular element of elongated shape (7) passing through at least one of said plurality of holes in the said proximal end (4) through the said first element (2), to said balloon is, in other words, an element in which, during the operative phase, the blood passing through the holes in the balloon (6) and said element (7) is channeled. In one embodiment, when there is a plurality of balloons (6), the flexible hollow tubular elements of elongated shape

[0083] (7) will be the same number as balloons, and the blood passing through each balloon (6) and each elongated flexible hollow tubular element (7) will be conveyed in the single line

[0084] (8). In one embodiment, said hollow tubular suction element (8) is connected to a device for creating a vacuum or negative pressure. In a preferred embodiment, said vacuumcreating device is a roller pump or a vacuum pump used in conventional extracorporeal circulation; in minimally invasive circulation, it will be connected to the venous return that is affected by the negative pressure of the thruster.

[0085] In one embodiment, the device (1) is a disposable device.

[0086] In one embodiment, said flexible hollow tubular element of elongated shape (9) passes through said distal end (3) and is configured for the connection to a fluid dispenser. In other words, said element (9) can be defined as a fill line.

[0087] In a preferred embodiment, said fluid is helium, CO2, or physiological solution. In a particularly preferred embodiment, this fluid is helium. The use of helium is particularly advantageous since it is a gas with a low embolic profile, and it has a density that is easy to monitor in terms of pressures and any leaks coming from the system used, thus it allows the use of a closed system and reducing fluid waste.

[0088] In one embodiment, said element (7) connected to said balloon (6) and to a hollow tubular suction element (8) passing through said first element (2) is configured to be connected to an extracorporeal circulation machine.

[0089] Extracorporeal circulation is a technique that allows the temporary replacement of the heart and lungs with a machine that replaces their functions, allowing to isolate the heart from the circulation and thus to perform ‘open heart’ surgery on the bloodless cardiac chambers. In extracorporeal circulation, or heart-lung machine, venous blood is taken from the venae cavae or directly from the right atrium, it passes into a device called oxygenator, where the venous blood is oxygenated by exposure to a flow of oxygen, and is then pumped into the patient's arterial system. The circuit is completed with a heat exchanger and with pumps that aspirate the residual blood from the surgical field. There is also a myocardial perfusion system to keep the heart alive during the operation, during which it is not perfused physiologically with oxygenated blood through the coronary arteries.

[0090] In one embodiment, the number of balloons (6) is a plurality (6a, 6b, 6c, 6d), preferably at least 2, 3 or 4. The assembly of one or more balloons (6) to the suction line (8) inside the first element (2) can be set up before or during surgery, depending on the number of balloons (6) that are desired to be anchored to the pulmonary veins. In particular, the blood entering the holes of the balloons (6) is conveyed into the suction line (8). This allows the operator to choose to selectively anchor one or more balloons (6) in relation to the visual bleeding, and therefore in relation to the severity of the venous return in the pulmonary veins.

[0091] In one embodiment, said balloon (6) has an elliptical shape.

[0092] In a further embodiment, said balloon (6) has a maximum filling volume of 1 to 10 ml, preferably 5 ml. This volume allows to obtain, when inflated and placed in a venous lumen, a maximum pressure of 150 to 180 mmHg. This pressure favorably determines an air-tight seal of the blood inside the venous lumen, providing in addition to aspiration also physical isolation of the bleeding, favoring the visualization of the surgical field.

[0093] In one embodiment, said balloon (6), and / or said element (7) connected to said balloon (6) and to a hollow tubular suction element (8) passing through said first element (2) is made of a polymeric material, preferably polyurethane. Polyurethane is a material that is highly resistant to high pressures, and has high biocompatibility and sustainability, and is therefore advantageous for use in the device of the invention.

[0094] In a further embodiment, the internal pressure of the balloon (6), when inflated, is such as to obtain a pressure of 150 to 180 mmHg in the pulmonary venous lumen. This pressure favorably determines an air-tight seal of the blood inside the venous lumen, providing in addition to aspiration also physical isolation of the bleeding, favoring the visualization of the surgical field.

[0095] In one embodiment, said balloon (6) comprises three medial holes and one central hole. The configuration of the holes on the balloon facilitates blood aspiration. However, it is possible to use a different number and arrangement of holes on the balloons, as known to the skilled person. In particular, it is preferable that the number and arrangement of the holes allow for a homogeneous management of blood suction throughout the lumen. In one embodiment, said balloon (6) and said flexible hollow element of elongated shape

[0096] (9) connected to said balloon to allow its inflation and deflation by the introduction of a fluid, are identified by a color code. To allow for proper identification, each balloon will be assigned a different color, for example red, green, yellow and purple, and each inflation / deflation line will be assigned the same color as the balloon to which it is connected.

[0097] In a preferred embodiment, the fluid dispensing device, and in particular for the administration of helium and the monitoring of pressures, comprises a helium cylinder, a management monitor, and a hardware system that dispenses helium in a closed circuit into the balloons (6) according to the color codes requested by the surgeon for their positioning.

[0098] In a preferred embodiment, said element (7) connected to said balloon (6) and to a hollow tubular suction element (8) passing through said first element (2) comprises an internal metallic shape memory structure. The use of an internal shape-memory metal structure allows the optimization of the space during use of the device (1), to select one or more balloons (6) to be inserted into the pulmonary venous lumen, avoiding the use of syringes with physiological solution which are bulky. Materials that can be used for a shapememory metal structure include shape-memory alloys (SMA), for example nitinol.

[0099] In one embodiment, said element (7) connected to said balloon (6) and to a hollow tubular suction element (8) passing through said first element (2) has a diameter of approximately 0.3 mm to approximately 3.3 mm, preferably approximately 1.67 mm. Using French (Fr) as a unit of measurement, the size of said element (7) ranges from 1 to 10 Fr, preferably 5 Fr.

[0100] In a preferred embodiment, said first flexible tubular element (2) has a diameter of about 3.3 to about 10 mm, preferably about 6.7 mm. Using French (Fr) as a unit of measure, the size of said element (2) ranges from 10 Fr to 30 Fr, preferably 20 Fr.

[0101] In one embodiment, the device (1) comprises inside the first element (2) a fixing system

[0102] (10) for fixing the internal elements to said first element (2). For example, said fixing system (10) consists of a wall inside the element (2) with holes through which the elements pass through the element (2).

[0103] Advantageously, the device (1) can be introduced into the body of a subject through the use of a conventional trocar.

[0104] In one embodiment, said device for controlling and / or managing the filling and internal pressure of the balloon (12) is connected to the device (1) by means of said flexible hollow element of elongated shape connected to said balloon to allow its inflation and deflation by the introduction of a fluid (9). In one embodiment, the device for controlling and / or managing the filling and internal pressure of the balloon (12), comprising a screen (13) for controlling and / or managing the filling pressure of balloons 6a, 6b, 6c and 6d, hardware for filling with the fluid (14), and a fluid storage device (15). In the embodiment where the fluid is helium, the storage device (15) is a helium cylinder.

[0105] The vacuum generating device is connected to the flexible hollow tubular element of elongated shape (8) by means of connecting devices to generate a vacuum or negative pressure, in order to allow suction.

[0106] Object of the invention is also a surgical method that comprises the insertion of the device for endocavitary aspiration (1) according to the present invention into the circulatory system of a subject.

[0107] In one embodiment, the method comprises a step of introducing at least one balloon (6) into a venous lumen, preferably a pulmonary venous lumen. In one embodiment, said balloon (6) is introduced into the right superior, left superior, right inferior, or left inferior pulmonary vein, introducing the device into the left atrium of the heart.

[0108] In a preferred embodiment, when the device (1) comprises a plurality of balloons (6), these can each be positioned in a pulmonary vein, up to a maximum of four balloons, therefore one for each pulmonary vein.

[0109] In one embodiment, the balloon(s) is (are) filled with helium, so as to obtain a total occlusion of the venous lumen in which the balloon is inserted.

[0110] In a further embodiment, the method comprises a passage of deflation of the balloon and removal of the device (1) from the subject's circulatory system.

Claims

CLAIMS1. A device for endocavitary aspiration (1) comprising:- a first flexible tubular element (2) of elongated shape having a distal end (3) and a proximal end (4), wherein said proximal end (4) is closed and includes a plurality of holes,- a hollow tubular element with an elongated helical shape (5) connected to said distal end (4) of said first tubular element (2), configured so as to allow suction,- at least one perforated inflatable balloon (6),- at least one flexible hollow tubular element of elongated shape (9) passing through at least one of said plurality of holes in said proximal end (4) through said first element (2), connected to said balloon to allow its inflation or deflation by introduction of a fluid,- at least one flexible hollow tubular element of elongated shape (7) passing through at least one of said plurality of holes in said proximal end (4) through said first element (2), connected to said balloon and to a hollow tubular suction element (8) passing through said first element (2), configured to allow suction, wherein said inflatable balloon (6), when placed inside a venous lumen, and inflated, completely occludes the venous lumen and allows the passage of blood towards said hollow tubular suction element (8) through the holes on said balloon.

2. The device according to claim 1 , wherein said flexible hollow tubular element of elongated shape (9) passes through said distal end (4) and inside said hollow tubular suction element (8) and said flexible hollow tubular element of elongated shape (7) and is configured for connection to a fluid dispenser, preferably in which said fluid is helium, CO2 or physiological solution.

3. The device according to any one of the preceding claims, in which said element (7) connected to said balloon (6) and to a hollow tubular suction element (8) passing through said first element (2) is configured to be connected to an extracorporeal circulation machine.

4. The device according to any one of the preceding claims, wherein the number of balloons (6) is a plurality, preferably at least 2, 3 or 4.

5. The device according to any one of the preceding claims, wherein said balloon (6), and / or said element (7) connected to said balloon (6) and to a hollow tubular suctionelement (8) passing through said first element (2) is made of a polymeric material, preferably polyurethane.

6. The device according to any one of the preceding claims, wherein said balloon (6) has a maximum filling volume of 1 to 10 ml, preferably 5 ml.

7. The device according to any one of the preceding claims, wherein said balloon (6) includes three medial holes and a central hole.

8. The device according to any one of the preceding claims, wherein said balloon (6) and said flexible hollow element of elongated shape (9) connected to said balloon to allow its inflation and deflation by introducing a fluid, are identified by a code color.

9. The device according to any one of the preceding claims, wherein said element (7) connected to said balloon (6) and to a hollow tubular suction element (8) passing through said first element (2) comprises an internal metallic shape memory structure.

10. A system for endocavitary aspiration (11) comprising a device (1) according to any one of claims 1 to 9, a device for controlling and / or monitoring the filling and internal pressure of the balloon (12), a device for extracorporeal circulation and / or a vacuum generating device to allow aspiration.

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