Description:FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION
(Section 10 and Rule 13)

1. TITLE OF THE INVENTION: CIRCULATORY SUPPORT SYSTEM
2. APPLICANT:
Meril Corporation (I) Private Limited, an Indian company of the address Survey No. 135/139, Muktanand Marg, Bilakhia House, Pardi, Vapi, Valsad-396191 Gujarat, India.

The following specification particularly describes the invention and the manner in which it is to be performed:

FIELD OF INVENTION
[1] The present disclosure relates to a medical device. More particularly, the present disclosure relates to a circulatory support system.
BACKGROUND OF INVENTION
[2] A circulatory system is an intricate combination of organs including heart and blood vessels through which blood is circulated throughout the entire body. The circulatory system is responsible to pump blood away from and towards the heart. The left ventricle of the heart is responsible for pumping oxygenated blood received from the lungs to the aorta to deliver the oxygenated blood to the rest of the body. The left ventricle receives oxygenated blood from the lungs via the left atrium (auricle). In other words, with each heartbeat, the left ventricle provides blood received from the left atrium to the aorta. The right ventricle of the heart is responsible for pumping deoxygenated blood received from the right atrium to the pulmonary artery.
[3] When the ejection fraction of the left ventricle and right ventricle falls below 50 percent, the heart no longer efficiently circulates blood. Low ejection fraction may be associated with one or more diseases or disorders such as congenital heart defects, cardiomyopathy, diabetes, coronary artery disease, myocardial infarction, or uncontrolled high blood pressure. Depending on the severity, the low ejection fraction may lead to reduced quality of life or death, if left untreated.
[4] Patients with severe heart failure, whether awaiting a heart transplant or ineligible for a transplant, are provided with Ventricular assist devices (VADs). Ventricular assist devices (VADs) may be used to help support blood circulation when the heart is unable to pump the blood effectively (i.e., help in pumping blood from the ventricles of the heart to the rest of the body).
[5] However, conventional VADs rely on multiple components for their operation. As a result, these components contribute to the overall bulkiness of a conventional VAD. This affects patient’s comfort and mobility (in other words, patients with these devices face challenges related to portability and daily activities).
[6] A conventional VAD uses pulsatile action of heart to mimic the natural systole and diastole phases of the cardiac cycle. The pulsatile action may create stress on the components, potentially leading to wear and tear or premature device failure.
[7] Hence, there is a need to devise a system that supports the circulation system and overcomes the problems associated with the conventional devices.
SUMMARY OF INVENTION
[8] Particular embodiments of the present disclosure are described herein below with reference to the accompanying drawings; however, it is to be understood that the disclosed embodiments are mere examples of the disclosure, which may be embodied in various forms. Well-known functions or constructions are not described in detail to avoid obscuring the present disclosure in unnecessary detail. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present disclosure in virtually any appropriately detailed structure.
[9] The present disclosure relates to a circulatory support system. The circulatory support system includes a tube extending from a proximal end to a distal end. The tube includes one or more first slits, one or more second slits, a lumen and one or more conduits. The one or more first slits are provided towards a distal portion of the tube. The one or more second slits are provided towards a central portion of the tube. The lumen includes a first section, a second section and a third section. The first section is provided proximal to the one or more first slits in the distal portion of the tube. The second section is provided between the first section and the third section. The third section is provided distal to the one or more second slits in the central portion of the tube. The first section is configured to receive blood from a low-pressure region via the one or more first slits. The third section is configured to release blood into a high-pressure region via the one or more second slits. The second section is configured to create a venturi effect between the low-pressure region of the first section and the high-pressure region of the third section within the tube, thereby facilitating a unidirectional blood flow. The one or more conduits is provided within a body of the tube. The one or more conduits extends from the proximal end of the tube to a third distal end of the third section. The one or more conduits are configured to inject a fluid at the third distal end of the third section in the lumen.
BRIEF DESCRIPTION OF INVENTION
[10] The summary above, as well as the following detailed description of illustrative embodiments, is better understood when read in conjunction with the apportioned drawings. For the purpose of illustrating the present disclosure, exemplary constructions of the disclosure are shown in the drawings. However, the disclosure is not limited to specific methods and instrumentality disclosed herein. Moreover, those in the art will understand that the drawings are not to scale.
[11] Fig. 1 illustrates a system 10, according to an embodiment of the present disclosure.
[12] Fig. 2 depicts a perspective side view of a tube 100, according to an embodiment of the present disclosure.
[13] Figs. 3a-3b depict cross-sectional views of the tube 100, according to an embodiment of the present disclosure.
[14] Fig. 4a depicts a side exploded view of a third section 200 of a lumen 140 in the tube 100, according to an embodiment of the present disclosure.
[15] Fig. 4b depicts a side perspective view of the proximal portion 100c of the tube 100, according to an embodiment of the present disclosure.
[16] Figs. 5a-5b illustrate the implantation of the tube 100 within a patient’s body, according to an embodiment of the present disclosure.
[17] Fig. 6 illustrates the flow of the blood and a fluid within the lumen 140 of the tube 100, according to an embodiment of the present disclosure.
DETAILED DESCRIPTION OF THE DRAWINGS
[18] Prior to describing the invention in detail, definitions of certain words or phrases used throughout this patent document will be defined: the terms "include" and "comprise", as well as derivatives thereof, mean inclusion without limitation; the term "or" is inclusive, meaning and/or; the phrases "coupled with" and "associated therewith", as well as derivatives thereof, may mean to include, be included within, interconnect with, contain, be contained within, connect to or with, couple to or with, be communicable with, cooperate with, interleave, juxtapose, be proximate to, be bound to or with, have a property of, or the like. Definitions of certain words and phrases are provided throughout this patent document, and those of ordinary skill in the art will understand that such definitions apply in many, if not most, instances to prior as well as future uses of such defined words and phrases.
[19] Reference throughout this specification to “one embodiment,” “an embodiment,” or similar language means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, appearances of the phrases “in one embodiment,” “in an embodiment,” and similar language throughout this specification may, but do not necessarily, all refer to the same embodiment, but mean “one or more but not all embodiments” unless expressly specified otherwise. The terms “including,” “comprising,” “having,” and variations thereof mean “including but not limited to” unless expressly specified otherwise. An enumerated listing of items does not imply that any or all of the items are mutually exclusive and/or mutually inclusive, unless expressly specified otherwise. The terms “a,” “an,” and “the” also refer to “one or more” unless expressly specified otherwise.
[20] Although the operations of exemplary embodiments of the disclosed method may be described in a particular, sequential order for convenient presentation, it should be understood that the disclosed embodiments can encompass an order of operations other than the particular, sequential order disclosed. For example, operations described sequentially may in some cases be rearranged or performed concurrently. Further, descriptions and disclosures provided in association with one particular embodiment are not limited to that embodiment, and may be applied to any embodiment disclosed herein. Moreover, for the sake of simplicity, the attached figures may not show the various ways in which the disclosed system, method, and apparatus can be used in combination with other systems, methods, and apparatuses.
[21] Furthermore, the described includes, advantages, and characteristics of the embodiments may be combined in any suitable manner. One skilled in the relevant art will recognize that the embodiments may be practiced without one or more of the specific includes or advantages of a particular embodiment. In other instances, additional includes and advantages may be recognized in certain embodiments that may not be present in all embodiments. These includes and advantages of the embodiments will become more fully apparent from the following description and apportioned claims, or may be learned by the practice of embodiments as set forth hereinafter.
[22] This current disclosure pertains to a circulatory support system (hereinafter, system). The system may be implanted in a patient with severe heart failure, whether awaiting a heart transplant or ineligible for a transplant. The system helps in achieving improved blood flow. In an exemplary embodiment, the system includes a tube. The system uses a tube that directs blood flow in a single direction (unidirectional flow) by employing the venturi effect. The system thus creates a pressure drop that facilitates unidirectional blood flow from the left ventricular chamber to the aorta.
[23] Although, the system of the present disclosure is described with the help of an example where the system supports a patient with an isolated aortic valve dysfunction, the teachings of the present disclosure are equally applicable to the system that supports patients with isolated pulmonic valve dysfunction, or bi-ventricular dysfunction. Minor modifications to adapt the system for isolated pulmonic valve dysfunction, or bi-ventricular dysfunction are within the scope of the teachings of the present disclosure.
[24] Unlike conventional VADs, this system provides continuous blood flow. This design reduces the risk of premature device failure and minimizes the chances of blood clot formation. In an exemplary embodiment, the system includes a pump. The pump is configured to push a fluid from a fluid reservoir into the tube. With fewer components than traditional VADs, the system of the present disclosure is less bulky, which enhances patient comfort and mobility.
[25] Now referring to the figures, Fig. 1 illustrates an exemplary embodiment of a circulatory support system 10 (hereinafter, system 10). In an exemplary embodiment, the system 10 includes a tube 100, a hose 300, a pump 400 and at least one fluid reservoir 500 (hereinafter, fluid reservoir 500).
[26] The tube 100 extends from a proximal end 100a to a distal end 100b, thereby defining a length of the tube 100. The length of the tube 100 may range between 73 mm to 76 mm. The tube 100 may have an external diameter ranging between 4.5 mm to 5.0 mm. In an exemplary embodiment, the length and the external diameter of the tube 100 are 75 mm and 4.8 mm, respectively. The tube 100 may be made of biocompatible material, including, without limitation, Nitinol, stainless steel, titanium, cobalt-chromium alloy, etc. or a combination thereof. In an exemplary embodiment, the tube 100 is made of Nitinol.
[27] The tube 100 is to be placed inside the heart of a patient. For example, the tube 100 may be placed in the aortic valve (depicted in Fig. 5b) or pulmonic valve depending upon the requirement of treatment. The tube 100 is configured to direct the flow of blood in a single direction (unidirectional flow), which has been explained later. In an exemplary embodiment, the blood flows in the proximal direction from the distal end 100b towards the proximal end 100a of the tube 100. In an exemplary embodiment, the tube 100 is a pressure pipe.
[28] The distal end 100b of the tube 100 may include an anchoring member 101. The anchoring member 101 helps in anchoring the tube 100 in a surrounding tissue and prevent dislocation of the tube 100 from its designated place. In an exemplary embodiment, the anchoring member 101 has a J-shape, though it may have any suitable shape. The anchoring member 101 may be made of biocompatible material, such as, without, limitation, polyurethane (PU), polyether block amide (PEBA), low density polyethylene (LDP), high density polyethylene (HDPE). In an exemplary embodiment, the anchoring member 101 is made of polyurethane (PU).
[29] The proximal end 100a of the tube 100 is coupled to the pump 400 via the hose 300. The hose 300 includes a proximal end 300a and a distal end 300b. The distal end 300b of the hose 300 is coupled to the proximal end 100a of the tube 100 using techniques, such as, without limitation, UV Bonding, medical adhesive, Loctite etc. In an exemplary embodiment, the distal end 300b of the hose 300 is coupled to the proximal end 100a of the tube 100 using UV Bonding. The hose 300 may have a length and a diameter ranging between 130 mm to 160 mm and 2.5 mm to 3 mm, respectively. In an exemplary embodiment, the length and the diameter of the hose 300 is 150 mm and 2.9 mm, respectively. The hose 300 may be made of one or more biocompatible materials, such as, without limitation, polyurethane (PU), polyether block amide (PEBA), low-density polyethylene (LDP), high-density polyethylene (HDPE). In an exemplary embodiment, the hose 300 is made of PU.
[30] The proximal end 300a of the hose 300 is coupled to one end of the pump 400. The proximal end 300a of the pump 400 is coupled to the fluid reservoir 500 using a corresponding connecting pipe 500a. The pump 400 remains outside of the body of the patient. The pump 400 may have one of an AC motor or DC motor. In an embodiment, the pump 400 has an AC motor. The pump 400 is configured to push a fluid from the fluid reservoir 500 into the tube 100 via the hose 300 at a pre-determined time interval. The fluid may be saline, blood or heparin or a combination thereof. In the depicted embodiment, one fluid reservoir 500 is coupled to the pump 400, though the system 10 may include more than one fluid reservoirs 500. The number of reservoirs may vary depending upon the requirement of a medical practitioner.
[31] The pump 400 is electrically coupled to a suitable power supply (not shown) using connecting wires. The power supply may be an external AC power supply or DC power supply. In an embodiment, the power supply is an external AC power supply. In yet another embodiment, the system 10 includes a battery pack to drive the pump 400. The pump 400 pushes the fluid into the tube 100. The pump 400 may be electrically coupled to a control unit (not shown). The controller may be a programmable logic controller (PLC), a microcontroller, or any other suitable circuit or computing device. The control unit is programmed to have one or more pre-defined settings, e.g., predetermined time interval for pump 400 activation. The control unit is configured to control the time interval of injection of the fluid from the fluid reservoir 500 into the hose 300. In an exemplary embodiment, the control unit is coupled to a relay switch (not shown). Though the control unit may be coupled to a solid-state switch. The relay switch is coupled to the power supply and the pump 400. The relay switch allows the power to flow from the power source to the pump 400 when activated.
[32] Fig. 2 depicts side perspective view of the tube 100, according to an embodiment of the present disclosure.
[33] In an embodiment, the tube 100 includes a proximal portion 100c, a distal portion 100d and a central portion 100e. The proximal portion 100c is provided towards the proximal end 100a. The distal portion 100d is provided towards the distal end 100b of the tube 100. The central portion 100e is provided between the proximal portion 100c and the distal portion 100d.
[34] The tube 100 has a tubular body, defining an outer surface 120.In an exemplary embodiment, the outer surface 120 of the tube 100 has a stepped configuration, though it may have a smooth, continuous profile. The body of the tube 100 may include portions of same or different diameters. For example, in an embodiment, the proximal portion 100c, the distal portion 100d and the central portion 100e have different diameters. The central portion 100e may have a diameter different from the proximal portion 100c and the distal portion 100d. The proximal portion 100c and the distal portion 100d may have same diameters.
[35] The proximal portion 100c includes a first proximal end P1 and a first distal end P2. And, the distal portion 100d includes a second proximal end D1 and a second distal end D2. The tube 100 includes a taper at either ends of the central portion 100e (i.e., a proximal end C1 and a distal end C2 of the central portion 100e). Alternately, the tube 100 may include a taper at least partially along its length towards the distal end 100b.
[36] The tube 100 includes one or more slits. In an embodiment, one or more sits includes one or more first slits 110a (hereinafter, referred as first slits 110a) and one or more second slits 110b (hereinafter second slits 110b).
[37] The first slits 110a and the second slits 110b may be hollow spaces or may be movable flaps. In an embodiment, the first slits 110a and the second slits 110b are hollow spaces. The first slits 110a and the second slits 110b of the tube 100 may be formed using techniques, such as, without limitation, laser cut, 3-D printing, etc. In an exemplary embodiment, the first slits 110a and the second slits 110b are cut through the body of tube 100 using laser cut technique. The first slits 110a are provided towards the second distal end D2 of the distal portion 100d. In an embodiment, the tube 100 includes two sets of first slits 110a. Though, the tube 100 may include one or more sets of first slits 110a. In an embodiment, each set of the first slits 110a are provided circumferentially on the tube 100 and are spaced equidistant from one another. Though, each set of first slits 110a may be spaced unevenly from one another. In the depicted embodiment, each set of the first slits 110a includes three slits. Though, each set of the first slits 110a may include the same or different number of slits. Slits of the respective set of the first slits 110a are aligned in a straight line parallel to a longitudinal axis of the tube 100. Alternate dispositions of the first slits are within the scope of the teachings of the present invention. Each first slit 110a may have the same or different shapes. The first slits 110a may have a rectangular, square or circular, etc., shape. In an exemplary embodiment, each first slit 110a has a rectangular shape.
[38] In an embodiment, the second slits 110b are provided towards the proximal end C1 of the central portion 100e. Though, the second slits 110b may be provided in the proximal portion 100c of the tube 100. In an embodiment, the tube 100 includes two sets of second slits 110b. Though, the tube 100 may include one or more sets of second slits 110b. In an embodiment, each set of the second slits 110b are provided circumferentially on the tube 100 and are spaced equidistant from one another. Though, each set of second slits 110b may be spaced unevenly from one another. In the depicted embodiment, each set of the second slits 110b includes three slits. Though, each set of the second slits 110b may include the same or different number of slits. Slits of the respective set of the second slits 110b are aligned in a straight line parallel to a longitudinal axis of the tube 100. Alternate dispositions of the second slits 110b are within the scope of the teachings of the present invention. Each second slits 110b may have the same or different shapes. The second slits 110b may have a rectangular, square or circular, etc., shape. In an exemplary embodiment, each second slit 110b has a square shape.
[39] The first slit 110a and second slit 110b may have a predefined length and a predefined width. The first slit 110a and the second slit 110b may have the same or different predefined length and predefined width. The predefined length and the predefined width may range between 1 mm and 1.5 mm, 1 mm and 1.5 mm, respectively. In an embodiment, the first slit 110a and the second slit 110b has the same predefined length and predefined width. In an embodiment, the predefined length and the predefined width of the first slit 110a and the second slit 110b are 1.3 mm and 1.2 mm, respectively. The blood enters into the lumen 140 of the tube 100 via the first slits 110a and leaves the tube 100 via the second slits 110b.
[40] Figs. 3a-3b depict cross-sectional views of the tube 100, according to an embodiment of the present disclosure. The tube 100 is hollow from inside, defining a lumen 140. The lumen 140 extends at least partially from the distal end 100b to the proximal end C1 of the central portion 100e of the tube 100. Though, the lumen 140 may extend from the distal end 100b to a portion between the proximal end P1 of the proximal portion 100c and the proximal end C1 of the central portion 100e of the tube 100. The lumen 140 provides a passage for the blood. Specifically, the lumen 140 facilitates a unidirectional flow of the blood. In an exemplary embodiment, the lumen 140 directs the flow of the blood from the distal end 100b towards the proximal end C1 of the central portion 100e of the tube 100, i.e., in a proximal direction. The blood enters the lumen 140 of the tube 100 via the first slits 110a and leaves the tube 100 via the second slits 110b.
[41] The lumen 140 has a stepped configuration, thereby dividing the lumen 140 into a first section 160, a second section 180 and a third section 200. The first section 160 is provided in the distal portion 100d of the tube 100 proximal to the first slits 110a. The third section 200 is provided in the central portion 100e of the tube 100 distal to the second slits 110b. The second section 180 is provided between the first section 160 and the third section 200. The first section 160 and the third section 200 may have same or different length. The first section 160 and the third section 200 may have same or different diameters.
[42] The first section 160 extends from a first proximal end 160a to a first distal end 160b. A length of the first section 160 may range between 18 mm to 22 mm. A cross-sectional diameter of the first section 160 may range between 3.3 mm to 3.8 mm. In an exemplary embodiment, the length and the cross-sectional diameter of the first section 160 are 20 mm and 3.5 mm, respectively. The first distal end 160b is provided towards the first slits 110a. The first proximal end 160a is provided towards the second section 180. The first section 160 of the lumen 140 is configured to receive blood from a low-pressure region (e.g., the left ventricular chamber of the heart) via the first slits 110a.
[43] In an embodiment, the stepped configuration is designed in the second section 180 of the lumen 140. The stepped configuration helps in creating a venturi effect across a length of the second section 180. In an exemplary embodiment, the second section 180 includes a first tapered portion 182 and a second tapered portion 186. The first tapered portion 182 faces towards the first section 160 and the second tapered portion 186 faces towards the third section 200. The first tapered portion 182 and the second tapered portion 186 converge at an apex 184. In the description of the present disclosure, the term 'apex' refers to a point where a first tapered portion 182 and a second tapered portion 186 of the second portion 180 meet. The first tapered portion 182, the apex 184 and the second tapered portion 186 include a corresponding cross-sectional diameter. The first tapered portion 182 and the second tapered portion 186 may have same or different length.
[44] The first tapered portion 182 receives the blood from the first proximal end 160a of the first section 160. The first tapered portion 182 is configured to increase the velocity and decrease the pressure of the blood passing through it. The first tapered portion 182 extends between the first proximal end 160a of the first section 160 and the apex 184, thereby defining a length of the first tapered portion 182. The length of the first tapered portion 182 may range between 2.5 mm to 2.7 mm. In an exemplary embodiment, the length of the first tapered portion 182 is 2.6 mm. The cross-sectional diameter of the first tapered portion 182 is configured to decrease gradually in the proximal direction i.e., from the first proximal end 160a to the apex 184. The gradual decrease in the cross-sectional diameter of the first tapered portion 182 is configured to increase the velocity and decrease the pressure of the blood flowing through the first tapered portion 182 in the proximal direction.
[45] The apex 184 of the second section 180 receives the blood from the first tapered portion 182. In an exemplary embodiment, the apex 184 has the narrowest cross-sectional diameter as compared to rest of the portions of the lumen 140. The cross-sectional diameter of the apex 184 may range between 0.6 mm to 0.8 mm. In an exemplary embodiment, the cross-sectional diameter of the apex 184 is 0.7 mm. The narrowest cross-sectional diameter of the apex 184 is configured to maximize the velocity and minimize the pressure of the blood flowing in the proximal direction.
[46] The second tapered portion 186 of the second section 180 receives the blood from the apex 184. The second tapered portion 186 is configured to recover the pressure lost by the blood in the first tapered portion (182) and the apex (184). The second tapered portion 186 extends between the apex 184 and the third section 200, thereby defining a length of the second tapered portion 186. The length of the second tapered portion 186 ranges between 2.5 mm to 2.7 mm. In an exemplary embodiment, the length of the second tapered portion 186 is 2.6 mm. The cross-sectional diameter of the second tapered portion 186 is configured to increase gradually in the proximal direction i.e., from the apex 184 to the third section 200 of the tube 100. The gradual increase in the cross-sectional diameter of the second tapered portion 186 is configured to decrease the velocity and increase the pressure of the blood flowing through the second tapered portion 186 in the proximal direction. The velocity of the blood passing through the second tapered portion 186 is low as compared to the velocity of the blood passing through the apex 184 of the second section 180. The pressure of the blood passing through the second tapered portion 186 is higher as compared to the blood flowing through the apex 184 of the second section 180. This gradual increase in the cross-sectional diameter helps in recovering the pressure lost by the blood in the first tapered portion 182 and the apex 184, thereby lowering the turbulence experienced by the blood.
[47] The third section 200 of the lumen 140 receives the blood from the second tapered portion 186. The third section 200 extends from a third proximal end 200a to a third distal end 200b, thereby defining a length of the third section 200. The third distal end 200b faces the second tapered portion 186 of the second section 180. The third proximal end 200a is provided towards the second slits 110b. The length of the third section 200 may range between 40 mm to 50 mm. The cross-sectional diameter of the third section 200 may range between 4.2 mm to 4.8 mm. In an exemplary embodiment, the length and the cross-sectional diameter of the third section 200 is 45 mm and 4.5 mm, respectively. The blood flows with a constant velocity and a constant pressure throughout the length of the third section 200. The third section 200 is configured to release blood into a high-pressure region (e.g., aorta of the heart) via the second slits 110b.
[48] The tube 100 includes one or more conduits 250 (hereinafter, referred as conduits 250) provided within the body of the tube 100. The conduits 250 extend at least partially within the body of the tube 100. Specifically, the conduits 250 extend longitudinally from the proximal end 100a of the tube 100 to the third distal end 200b of the third section 200. In one depicted embodiment, the tube 100 includes five conduits 250, as shown in Fig. 4a. In yet another embodiment, the tube 100 includes eight conduits 250, as shown in Fig. 4b. Each conduit 250 includes a diameter less than the thickness of the body of the tube 100. The diameter of each conduit 250 may range between 0.2 mm to 0.3 mm. Each conduit 250 may have same or varying diameters. In an exemplary embodiment, the diameter of each conduit 250 is 0.25 mm.
[49] The conduits 250 are arranged longitudinally within the body of the tube 100 without intersecting the second slits 110b. In other words, each conduit 250 is aligned along a corresponding longitudinal axis that is different than the longitudinal axis of the corresponding second slit 110b/set of second slits 110b. The tube 100 may include equal or different number of second slit 110b/set of second slits 110b and the conduits 250. The conduits 250 may be positioned along the longitudinal axis in a regular or an alternating pattern with the longitudinal axis of the second slits 110b/set of second slits 110b. The conduit/conduits 250 and the second slit/set of second slits 110b, each having a respective longitudinal axis, may be arranged either equidistant or may be spaced unevenly from each other.
[50] The tube 100 may include equal number of conduits 250 and the second slits 110b, arranged along the longitudinal axis of the tube 100 without following a regular or alternating pattern, with each conduit 250 and each second slit 110b occupying a separate axis. The tube 100 may include an unequal number of conduits 250 and the second slits 110b, each aligned along the respective longitudinal axis, arranged unevenly without a regular or alternating pattern.
[51] Fig. 4b depicts an exemplary arrangement of conduits with respect to the second slits 110b. In the depicted embodiment, the tube 100 includes two sets of conduits 250 and two sets of second slits 110b. Each set of conduits 250 includes four conduits 250. Each conduit 250 in the set of conduits 250 are arranged equidistantly and parallel with each other. Each set of conduits 250 are arranged in an alternating pattern with the sets of second slits 110b.
[52] The conduits 250 within the body of the tube 100 may be formed using techniques, such as, without limitations, laser cut, 3D Printing, etc. In an exemplary embodiment, the conduits 250 within the body of the tube 100 is formed using laser cut technique. The conduits 250 provides a passage for the fluid to pass. Each conduit 250 includes a proximal end 250a and a curved distal end 250b (hereinafter, curved end 250b). The proximal end 250a of each conduit 250 is provided towards the proximal end 100a of the tube 100. In other words, the proximal end 250a of each conduit 250 ends in the distal end 300b of the hose 300. The proximal end 250a of the conduits 250 receives the fluid from the hose 300. The curved end 250b of each conduit 250 is provided towards the third distal end 200b of the third section 200. The curved end 250b is configured to inject the fluid into the third section 200 at the third distal end 200b, continuously. The continuous injection of the fluid is configured to create a high-velocity stream in the flow of the blood and helps in maintaining a low pressure in the third section 200 than the pressure in the first section 160. This prevents backflow of the blood from third section 200 back into the second section 180. Figs. 5a-5b illustrate the implantation of the tube 100, according to an embodiment of the present disclosure. During a medical procedure, a minimal invasive procedure such as a transcatheter technique may be used for delivery of the tube 100. The tube 100 may be delivered at a target site, for example, an aortic valve, or a pulmonic valve via an appropriate vascular access point. The tube 100 is pre-attached with the hose 300 and is pre-loaded into a delivery catheter or sheath (not shown). During the medical procedure, the catheter/sheath is routed to the target site with the help of a guidewire (not shown).
[53] In the illustrated embodiment, the catheter/sheath (not shown) is inserted into the patient’s body via the femoral artery in the groin region and is guided up to the heart. Fluoroscopic imaging techniques may be used to guide and monitor the advancement of the catheter/sheath during the procedure. Once the catheter/sheath approaches the target site, for example near the aortic valve, the tube 100 is delivered and positioned in the aortic valve, as shown in Fig. 5b. The first section 160 of the tube 100 is positioned within the left ventricle, where blood is to be received during the ventricular contraction (systole). The second section, including the first tapered portion 182 and the apex 184, is positioned towards the left ventricle apex. The second tapered portion 186 is positioned in the left ventricle outflow tract. The third distal end 200b of the third section 200 is positioned just before the aortic valve. The third proximal end 200a with the second slits 110b is positioned within the ascending aorta (beyond the aortic valve), where blood is to be released.
[54] Once the tube 100 is positioned, the catheter/ sheath is retracted, leaving the tube 100 and the hose 300 inside. The tube 100 remains at the aortic valve. The hose 300 remains inside of the body of the patient, as shown in Fig. 5a. A proximal portion of the hose 300 extends outside of the body (i.e., from the incision point) and is coupled to the pump 400.
[55] During diastole, the atrial chambers contract and the ventricular chambers relax. The atrioventricular valves (valve between the atria and the left ventricles) remain open. Due to the contraction of the atria, the ventricular chambers receive blood from the atrial chambers. The left ventricle chamber receives oxygenated blood from the left atria. The first section 160 in the lumen 140 of the tube 100 receives the blood via the first slits 110a. The pump 400 pushes the fluid from the reservoir into the conduits 250 via the hose 300. The conduits 250 pour the fluid into the third section 200 at the distal third end 180b. The fluid flowing into the third section 200 maintains a low pressure in the third section 200. As a result, a pressure differential is created between the first section 160 and the third section 200. Due to the closure of the aortic valve (valve between the left ventricle and the aorta) and the relaxed muscles of the left ventricular chamber, there is a negligible force acting upon the blood to push the blood from the first section 160 into the second section 180 of the lumen 140. As a result, a vacuum effect is maintained within the second section 180 of the lumen 140 during diastole.
[56] During systole, the atrioventricular valves are closed and the ventricles contract. Due to the contraction of the ventricles, the blood in the ventricles is pushed into the first section 160 of the lumen 140 in the tube 100 via the first slits 110a, as show in Fig. 6. The blood in the first section 160 is further pushed to flow into the second section 180.
[57] As the blood passes through the second section, the blood experiences turbulence. The second section 180 is configured to create a venturi effect between the low-pressure region of the first section 160 and the high-pressure region of the third section 200 within the tube 100. As the blood passes through the first tapered portion 182 of the second section 180, the velocity of blood flowing through the first tapered section 182 gradually increases. And, the pressure with which the blood flows across the first tapered portion 182 gradually decreases. This is due to the gradual decrease in the cross-sectional diameter of the first tapered portion 182. The blood then passes through the apex 184 and enters into the second tapered portion 186 with the highest velocity and the lowest pressure. This is due to the narrowest cross-sectional diameter of the apex 184 that maximizes the velocity and the minimizes the pressure of the blood flowing through it. Due to the gradual increase in the cross-sectional diameter of the second tapered portion 186, the velocity of the blood decreases and the pressure of the blood is restored, thereby facilitating a unidirectional blood flow.
[58] The blood then moves into the third section 200 of the lumen 140. The pump 400 pushes the fluid from the fluid reservoir 500 into the conduits 250 via the hose 300. The conduits 250 inject the fluid into the third section 200 of the lumen 140. As the fluid enters into the third section 200 of the lumen 140, a high-velocity stream is created. This high-velocity stream of the fluid further reduces the pressure at the third distal end 200b of the third section 200 in the lumen 140. The continuous injection of the fluid helps in maintaining a low pressure in the third section 200 than the pressure in the first section 160. By maintaining a lower pressure at the third distal end 200b of the third section 200, a pressure differential between the second portion 180 and the third section 200 remains high, ensuring the pressure is maintained. This prevents backflow of the blood from third section 200 back into the second section 180.
[59] The scope of the invention is only limited by the appended patent claims. More generally, those skilled in the art will readily appreciate that all parameters, dimensions, materials, and configurations described herein are meant to be exemplary and that the actual parameters, dimensions, materials, and/or configurations will depend upon the specific application or applications for which the teachings of the present invention is/are used. , Claims:WE CLAIM:
1. A circulatory support system (10) comprising:
a. a tube (100) extending from a proximal end (100a) to a distal end (100b), the tube (100) includes:
I. one or more first slits (110a) provided towards a distal portion (100d) of the tube (100);
II. one or more second slits (110b) provided towards a central portion (100e) of the tube (100);
III. a lumen (140) having:
i. a first section (160) provided in the distal portion (100d) of the tube (100) proximal to the one or more first slits (110a), the first section (160) configured to receive blood from a low-pressure region via the one or more first slits (110a),
ii. a third section (200) provided in the central portion (100e) of the tube (100) distal to the one or more second slits (110b), the third section (200) is configured to release blood into a high-pressure region via the one or more second slits (110b); and
iii. a second section (180) provided between the first section (160) and the third section (200); and
IV. one or more conduits (250) extending within a body of the tube (100) from the proximal end (100a) of the tube (100) to a third distal end (200b) of the third section (200);
wherein, the second section (180) is configured to create a venturi effect between the low-pressure region of the first section (160) and the high-pressure region of the third section (200) within the tube (100), thereby facilitating a unidirectional blood flow;
wherein, the one or more conduits (250) are configured to inject a fluid at the third distal end (200b) of the third section (200) in the lumen (140).
2. The circulatory support system (10) as claimed in claim 1, wherein the second section (180) includes:
a. a first tapered portion (182) facing towards the first section (160), the first tapered portion (182) includes a cross-sectional diameter gradually decreasing throughout a length of the first tapered portion (182) in a proximal direction, to increase the velocity and decrease the pressure of the blood; and
b. a second tapered portion (186) facing towards the third section (200), the second tapered portion (186) includes gradually increasing cross-sectional diameter throughout a length of the second tapered portion (186) in the proximal direction, the second tapered portion (186) is configured to recover the pressure lost by the blood in the first tapered portion (182), thereby lowering the turbulence experienced by the blood;
wherein, the first tapered portion (182) and the second tapered portion (186) converge at an apex (184) having the narrowest cross-sectional diameter configured to maximize the velocity and minimize the pressure of the blood flow.
3. The circulatory support system (10) as claimed in claim 2, wherein the first tapered portion (182) and the second tapered portion (186) have one of same or different length.
4. The circulatory support system (10) as claimed in claim 1, wherein the distal end (100b) of the tube (100) includes an anchoring member (101) configured to anchor the tube (100) in a surrounding tissue.
5. The circulatory support system (10) as claimed in claim 1, wherein the first section (160) and the third section (200) have one of same or different cross-sectional diameter.
6. The circulatory support system (10) as claimed in claim 1, wherein the first section (160) and the third section (200) have one of same length or different length.
7. The circulatory support system (10) as claimed in claim 1, wherein the tube (100) is made of one of biocompatible material including, nitinol, stainless steel, titanium, cobalt-chromium alloy, or a combination thereof.
8. The circulatory support system (10) as claimed in claim 1, wherein the one or more conduits (250) have one of same or different diameter.
9. The circulatory support system (10) as claimed in claim 1, wherein the system (10) includes a pump (400) coupled to the proximal end (100a) of the tube (100), the pump (400) is configured to push the fluid from the fluid reservoir (500) into the one or more conduits (250).
10. The circulatory support system (10) as claimed in claim 1, wherein the one or more conduits (250) are aligned along a corresponding longitudinal axis that is different than a longitudinal axis of the corresponding one or more second slits (110b).