Circulatory support system
Patent Information
- Authority / Receiving Office
- IN · IN
- Patent Type
- Patents
- Current Assignee / Owner
- MERIL CORP (I) PTE LTD
- Filing Date
- 2024-08-21
- Publication Date
- 2026-07-15
AI Technical Summary
Conventional Ventricular Assist Devices (VADs) are bulky, reduce patient comfort and mobility, and are prone to premature failure due to pulsatile action, which can lead to stress and wear on components, especially in patients with severe heart failure.
A circulatory support system featuring a tube with slits and conduits that utilize a venturi effect to facilitate unidirectional blood flow, reducing the risk of premature device failure and minimizing blood clot formation, while being less bulky and more portable than traditional VADs.
The system provides continuous blood flow, enhances patient comfort and mobility, and reduces the risk of device failure by using a fewer components and minimizing stress on the device, thus improving the quality of life for patients with severe heart failure.
Abstract
Description
FIELD OF INVENTION[1] The present disclosure relates to a medical device. More particularly, thepresent disclosure relates to a circulatory support system.BACKGROUND OF INVENTION[2] A circulatory system is an intricate combination of organs including heart andblood vessels through which blood is circulated throughout the entire body. Thecirculatory system is responsible to pump blood away from and towards the heart.The left ventricle of the heart is responsible for pumping oxygenated blood receivedfrom 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 bloodreceived from the left atrium to the aorta. The right ventricle of the heart isresponsible for pumping deoxygenated blood received from the right atrium to thepulmonary artery.[3] When the ejection fraction of the left ventricle and right ventricle falls below50 percent, the heart no longer efficiently circulates blood. Low ejection fractionmay be associated with one or more diseases or disorders such as congenital heartdefects, cardiomyopathy, diabetes, coronary artery disease, myocardial infarction,or uncontrolled high blood pressure. Depending on the severity, the low ejectionfraction may lead to reduced quality of life or death, if left untreated.[4] Patients with severe heart failure, whether awaiting a heart transplant orineligible for a transplant, are provided with Ventricular assist devices (VADs).Ventricular assist devices (VADs) may be used to help support blood circulationwhen the heart is unable to pump the blood effectively (i.e., help in pumping bloodfrom the ventricles of the heart to the rest of the body).[5] However, conventional VADs rely on multiple components for theiroperation. As a result, these components contribute to the overall bulkiness of aconventional VAD. This affects patient's comfort and mobility (in other words,patients with these devices face challenges related to portability and dailyactivities).[6] A conventional VAD uses pulsatile action of heart to mimic the natural systoleand diastole phases of the cardiac cycle. The pulsatile action may create stress onthe 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 systemand overcomes the problems associated with the conventional devices.SUMMARY OF INVENTION[8] Particular embodiments of the present disclosure are described herein belowwith reference to the accompanying drawings; however, it is to be understood thatthe disclosed embodiments are mere examples of the disclosure, which may beembodied in various forms. Well-known functions or constructions are notdescribed in detail to avoid obscuring the present disclosure in unnecessary detail.Therefore, specific structural and functional details disclosed herein are not to beinterpreted as limiting, but merely as a basis for the claims and as a representativebasis for teaching one skilled in the art to variously employ the present disclosurein virtually any appropriately detailed structure.[9] The present disclosure relates to a circulatory support system. Thecirculatory support system includes a tube extending from a proximal end to a distalend. The tube includes one or more first slits, one or more second slits, a lumen andone or more conduits. The one or more first slits are provided towards a distalportion of the tube. The one or more second slits are provided towards a centralportion of the tube. The lumen includes a first section, a second section and a thirdsection. The first section is provided proximal to the one or more first slits in thedistal portion of the tube. The second section is provided between the first sectionand the third section. The third section is provided distal to the one or more secondslits in the central portion of the tube. The first section is configured to receiveblood from a low-pressure region via the one or more first slits. The third section isconfigured to release blood into a high-pressure region via the one or more secondslits. 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 sectionwithin the tube, thereby facilitating a unidirectional blood flow. The one or moreconduits is provided within a body of the tube. The one or more conduits extendsfrom the proximal end of the tube to a third distal end of the third section. The oneor more conduits are configured to inject a fluid at the third distal end of the thirdsection in the lumen.BRIEF DESCRIPTION OF INVENTION
[10] The summary above, as well as the following detailed description ofillustrative embodiments, is better understood when read in conjunction with theapportioned drawings. For the purpose of illustrating the present disclosure,exemplary constructions of the disclosure are shown in the drawings. However, thedisclosure 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 presentdisclosure.
[12] Fig. 2 depicts a perspective side view of a tube 100, according to anembodiment of the present disclosure.
[13] Figs. 3a-3b depict cross-sectional views of the tube 100, according to anembodiment of the present disclosure.
[14] Fig. 4a depicts a side exploded view of a third section 200 of a lumen 140 inthe tube 100, according to an embodiment of the present disclosure.
[15] Fig. 4b depicts a side perspective view of the proximal portion 100c of thetube 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 thetube 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 orphrases 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, beincluded within, interconnect with, contain, be contained within, connect to orwith, 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 patentdocument, and those of ordinary skill in the art will understand that such definitionsapply in many, if not most, instances to prior as well as future uses of such definedwords and phrases.
[19] Reference throughout this specification to "one embodiment," "anembodiment," or similar language means that a particular feature, structure, orcharacteristic described in connection with the embodiment is included in at leastone embodiment. Thus, appearances of the phrases "in one embodiment," "in anembodiment," and similar language throughout this specification may, but do notnecessarily, all refer to the same embodiment, but mean "one or more but not allembodiments" 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 implythat any or all of the items are mutually exclusive and / or mutually inclusive, unlessexpressly specified otherwise. The terms "a," "an," and "the" also refer to "one ormore" unless expressly specified otherwise.
[20] Although the operations of exemplary embodiments of the disclosed methodmay be described in a particular, sequential order for convenient presentation, itshould be understood that the disclosed embodiments can encompass an order ofoperations other than the particular, sequential order disclosed. For example,operations described sequentially may in some cases be rearranged or performedconcurrently. Further, descriptions and disclosures provided in association with oneparticular embodiment are not limited to that embodiment, and may be applied toany embodiment disclosed herein. Moreover, for the sake of simplicity, theattached 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 theembodiments may be combined in any suitable manner. One skilled in the relevantart will recognize that the embodiments may be practiced without one or more ofthe specific includes or advantages of a particular embodiment. In other instances,additional includes and advantages may be recognized in certain embodiments thatmay not be present in all embodiments. These includes and advantages of theembodiments will become more fully apparent from the following description andapportioned claims, or may be learned by the practice of embodiments as set forthhereinafter.
[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 helpsin achieving improved blood flow. In an exemplary embodiment, the systemincludes 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 apressure drop that facilitates unidirectional blood flow from the left ventricularchamber to the aorta.
[23] Although, the system of the present disclosure is described with the help ofan example where the system supports a patient with an isolated aortic valvedysfunction, the teachings of the present disclosure are equally applicable to thesystem that supports patients with isolated pulmonic valve dysfunction, or bi-ventricular dysfunction. Minor modifications to adapt the system for isolatedpulmonic valve dysfunction, or bi-ventricular dysfunction are within the scope ofthe teachings of the present disclosure.
[24] Unlike conventional VADs, this system provides continuous blood flow. Thisdesign reduces the risk of premature device failure and minimizes the chances ofblood 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. Withfewer components than traditional VADs, the system of the present disclosure isless bulky, which enhances patient comfort and mobility.
[25] Now referring to the figures, Fig. 1 illustrates an exemplary embodiment of acirculatory support system 10 (hereinafter, system 10). In an exemplaryembodiment, the system 10 includes a tube 100, a hose 300, a pump 400 and atleast one fluid reservoir 500 (hereinafter, fluid reservoir 500).
[26] The tube 100 extendsfrom a proximal end 100a to a distal end 100b, therebydefining a length of the tube 100. The length of the tube 100 may range between73 mm to 76 mm. The tube 100 may have an external diameter ranging between4.5 mm to 5.0 mm. In an exemplary embodiment, the length and the externaldiameter of the tube 100 are 75 mm and 4.8 mm, respectively. The tube 100 maybe made of biocompatible material, including, without limitation, Nitinol, stainlesssteel, titanium, cobalt-chromium alloy, etc. or a combination thereof. In anexemplary embodiment, the tube 100 is made of Nitinol.
[27] The tube 100 is to be placed inside the heart of a patient. For example, thetube 100 may be placed in the aortic valve (depicted in Fig. 5b) or pulmonic valvedepending upon the requirement of treatment. The tube 100 is configured to directthe flow of blood in a single direction (unidirectional flow), which has beenexplained later. In an exemplary embodiment, the blood flows in the proximaldirection 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 tissueand prevent dislocation of the tube 100 from its designated place. In an exemplaryembodiment, the anchoring member 101 has a J-shape, though it may have anysuitable shape. The anchoring member 101 may be made of biocompatiblematerial, such as, without, limitation, polyurethane (PU), polyether block amide(PEBA), low density polyethylene (LDP), high density polyethylene (HDPE). In anexemplary 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 thehose 300. The hose 300 includes a proximal end 300a and a distal end 300b. Thedistal end 300b of the hose 300 is coupled to the proximal end 100a of the tube 100using techniques, such as, without limitation, UV Bonding, medical adhesive, Loctiteetc. In an exemplary embodiment, the distal end 300b of the hose 300 is coupledto the proximal end 100a of the tube 100 using UV Bonding. The hose 300 mayhave a length and a diameter ranging between 130 mm to 160 mm and 2.5 mm to3 mm, respectively. In an exemplary embodiment, the length and the diameter ofthe hose 300 is 150 mm and 2.9 mm, respectively. The hose 300 may be made ofone or more biocompatible materials, such as, without limitation, polyurethane(PU), polyether block amide (PEBA), low-density polyethylene (LDP), high-densitypolyethylene (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 pump400. The proximal end 300a of the pump 400 is coupled to the fluid reservoir 500using a corresponding connecting pipe 500a. The pump 400 remains outside of thebody of the patient. The pump 400 may have one of an AC motor or DC motor. Inan embodiment, the pump 400 has an AC motor. The pump 400 is configured topush 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 acombination thereof. In the depicted embodiment, one fluid reservoir 500 iscoupled to the pump 400, though the system 10 may include more than one fluidreservoirs 500. The number of reservoirs may vary depending upon therequirement 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 orDC power supply. In an embodiment, the power supply is an external AC powersupply. In yet another embodiment, the system 10 includes a battery pack to drivethe pump 400. The pump 400 pushes the fluid into the tube 100. The pump 400may be electrically coupled to a control unit (not shown). The controller may be aprogrammable logic controller (PLC), a microcontroller, or any other suitable circuitor computing device. The control unit is programmed to have one or more pre-defined settings, e.g., predetermined time interval for pump 400 activation. Thecontrol unit is configured to control the time interval of injection of the fluid fromthe fluid reservoir 500 into the hose 300. In an exemplary embodiment, the controlunit is coupled to a relay switch (not shown). Though the control unit may becoupled to a solid-state switch. The relay switch is coupled to the power supply andthe pump 400. The relay switch allows the power to flow from the power source tothe pump 400 when activated.
[32] Fig. 2 depicts side perspective view of the tube 100, according to anembodiment of the present disclosure.
[33] In an embodiment, the tube 100 includes a proximal portion 100c, a distalportion 100d and a central portion 100e. The proximal portion 100c is providedtowards the proximal end 100a. The distal portion 100d is provided towards thedistal end 100b of the tube 100. The central portion 100e is provided between theproximal portion 100c and the distal portion 100d.
[34] The tube 100 has a tubular body, defining an outer surface 120.In anexemplary embodiment, the outer surface 120 of the tube 100 has a steppedconfiguration, though it may have a smooth, continuous profile. The body of thetube 100 may include portions of same or different diameters. For example, in anembodiment, the proximal portion 100c, the distal portion 100d and the centralportion 100e have different diameters. The central portion 100e may have adiameter different from the proximal portion 100c and the distal portion 100d. Theproximal 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 distalend P2. And, the distal portion 100d includes a second proximal end D1 and asecond distal end D2. The tube 100 includes a taper at either ends of the centralportion 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 lengthtowards the distal end 100b.
[36] The tube 100 includes one or more slits. In an embodiment, one or more sitsincludes one or more first slits 110a (hereinafter, referred as first slits 110a) andone 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 bemovable flaps. In an embodiment, the first slits 110a and the second slits 110b arehollow spaces. The first slits 110a and the second slits 110b of the tube 100 may beformed using techniques, such as, without limitation, laser cut, 3-D printing, etc. Inan exemplary embodiment, the first slits 110a and the second slits 110b are cutthrough the body of tube 100 using laser cut technique. The first slits 110a areprovided towards the second distal end D2 of the distal portion 100d. In anembodiment, the tube 100 includes two sets of first slits 110a. Though, the tube100 may include one or more sets of first slits 110a. In an embodiment, each set ofthe first slits 110a are provided circumferentially on the tube 100 and are spacedequidistant from one another. Though, each set of first slits 110a may be spacedunevenly from one another. In the depicted embodiment, each set of the first slits110a includes three slits. Though, each set of the first slits 110a may include thesame or different number of slits. Slits of the respective set of the first slits 110a arealigned in a straight line parallel to a longitudinal axis of the tube 100. Alternatedispositions of the first slits are within the scope of the teachings of the presentinvention. Each first slit 110a may have the same or different shapes. The first slits110a may have a rectangular, square or circular, etc., shape. In an exemplaryembodiment, each first slit 110a has a rectangular shape.
[38] In an embodiment, the second slits 110b are provided towards the proximalend C1 of the central portion 100e. Though, the second slits 110b may be providedin the proximal portion 100c of the tube 100. In an embodiment, the tube 100includes two sets of second slits 110b. Though, the tube 100 may include one ormore sets of second slits 110b. In an embodiment, each set of the second slits 110bare provided circumferentially on the tube 100 and are spaced equidistant from oneanother. Though, each set of second slits 110b may be spaced unevenly from oneanother. In the depicted embodiment, each set of the second slits 110b includesthree slits. Though, each set of the second slits 110b may include the same ordifferent number of slits. Slits of the respective set of the second slits 110b arealigned in a straight line parallel to a longitudinal axis of the tube 100. Alternatedispositions of the second slits 110b are within the scope of the teachings of thepresent 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 anexemplary embodiment, each second slit 110b has a square shape.
[39] The first slit 110a and second slit 110b may have a predefined length and apredefined width. The first slit 110a and the second slit 110b may have the same ordifferent predefined length and predefined width. The predefined length and thepredefined 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 thesame predefined length and predefined width. In an embodiment, the predefinedlength and the predefined width of the first slit 110a and the second slit 110b are1.3 mm and 1.2 mm, respectively. The blood enters into the lumen 140 of the tube100 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 anembodiment of the present disclosure. The tube 100 is hollow from inside, defininga lumen 140. The lumen 140 extends at least partially from the distal end 100b tothe proximal end C1 of the central portion 100e of the tube 100. Though, the lumen140 may extend from the distal end 100b to a portion between the proximal endP1 of the proximal portion 100c and the proximal end C1 of the central portion 100eof the tube 100. The lumen 140 provides a passage for the blood. Specifically, thelumen 140 facilitates a unidirectional flow of the blood. In an exemplaryembodiment, the lumen 140 directs the flow of the blood from the distal end 100btowards the proximal end C1 of the central portion 100e of the tube 100, i.e., in aproximal direction. The blood enters the lumen 140 of the tube 100 via the first slits110a and leaves the tube 100 via the second slits 110b.
[41] The lumen 140 has a stepped configuration, thereby dividing the lumen 140into a first section 160, a second section 180 and a third section 200. The firstsection 160 is provided in the distal portion 100d of the tube 100 proximal to thefirst slits 110a. The third section 200 is provided in the central portion 100e of thetube 100 distal to the second slits 110b. The second section 180 is providedbetween the first section 160 and the third section 200. The first section 160 andthe third section 200 may have same or different length. The first section 160 andthe third section 200 may have same or different diameters.
[42] The first section 160 extends from a first proximal end 160a to a first distalend 160b. A length of the first section 160 may range between 18 mm to 22 mm. Across-sectional diameter of the first section 160 may range between 3.3 mm to 3.8mm. In an exemplary embodiment, the length and the cross-sectional diameter ofthe first section 160 are 20 mm and 3.5 mm, respectively. The first distal end 160bis provided towards the first slits 110a. The first proximal end 160a is providedtowards the second section 180. The first section 160 of the lumen 140 is configuredto receive blood from a low-pressure region (e.g., the left ventricular chamber ofthe heart) via the first slits 110a.
[43] In an embodiment, the stepped configuration is designed in the secondsection 180 of the lumen 140. The stepped configuration helps in creating a venturieffect across a length of the second section 180. In an exemplary embodiment, thesecond section 180 includes a first tapered portion 182 and a second taperedportion 186. The first tapered portion 182 faces towards the first section 160 andthe second tapered portion 186 faces towards the third section 200. The firsttapered 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 wherea first tapered portion 182 and a second tapered portion 186 of the second portion180 meet. The first tapered portion 182, the apex 184 and the second taperedportion 186 include a corresponding cross-sectional diameter. The first taperedportion 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 end160a of the first section 160. The first tapered portion 182 is configured to increasethe velocity and decrease the pressure of the blood passing through it. The firsttapered portion 182 extends between the first proximal end 160a of the first section160 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 todecrease gradually in the proximal direction i.e., from the first proximal end 160ato the apex 184. The gradual decrease in the cross-sectional diameter of the firsttapered portion 182 is configured to increase the velocity and decrease thepressure of the blood flowing through the first tapered portion 182 in the proximaldirection.
[45] The apex 184 of the second section 180 receives the blood from the firsttapered portion 182. In an exemplary embodiment, the apex 184 has the narrowestcross-sectional diameter as compared to rest of the portions of the lumen 140. Thecross-sectional diameter of the apex 184 may range between 0.6 mm to 0.8 mm. Inan 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 maximizethe velocity and minimize the pressure of the blood flowing in the proximaldirection.
[46] The second tapered portion 186 of the second section 180 receives the bloodfrom the apex 184. The second tapered portion 186 is configured to recover thepressure lost by the blood in the first tapered portion (182) and the apex (184). Thesecond tapered portion 186 extends between the apex 184 and the third section200, thereby defining a length of the second tapered portion 186. The length of thesecond tapered portion 186 ranges between 2.5 mm to 2.7 mm. In an exemplaryembodiment, 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 increasegradually in the proximal direction i.e., from the apex 184 to the third section 200of the tube 100. The gradual increase in the cross-sectional diameter of the secondtapered portion 186 is configured to decrease the velocity and increase thepressure of the blood flowing through the second tapered portion 186 in theproximal direction. The velocity of the blood passing through the second taperedportion 186 is low as compared to the velocity of the blood passing through theapex 184 of the second section 180. The pressure of the blood passing through thesecond tapered portion 186 is higher as compared to the blood flowing through theapex 184 of the second section 180. This gradual increase in the cross-sectionaldiameter helps in recovering the pressure lost by the blood in the first taperedportion 182 and the apex 184, thereby lowering the turbulence experienced by theblood.
[47] The third section 200 of the lumen 140 receives the blood from the secondtapered portion 186. The third section 200 extends from a third proximal end 200ato a third distal end 200b, thereby defining a length of the third section 200. Thethird distal end 200b faces the second tapered portion 186 of the second section180. The third proximal end 200a is provided towards the second slits 110b. Thelength 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 thethird section 200 is 45 mm and 4.5 mm, respectively. The blood flows with aconstant velocity and a constant pressure throughout the length of the third section200. 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 asconduits 250) provided within the body of the tube 100. The conduits 250 extendat least partially within the body of the tube 100. Specifically, the conduits 250extend longitudinally from the proximal end 100a of the tube 100 to the third distalend 200b of the third section 200. In one depicted embodiment, the tube 100includes five conduits 250, as shown in Fig. 4a. In yet another embodiment, the tube100 includes eight conduits 250, as shown in Fig. 4b. Each conduit 250 includes adiameter less than the thickness of the body of the tube 100. The diameter of eachconduit 250 may range between 0.2 mm to 0.3 mm. Each conduit 250 may havesame or varying diameters. In an exemplary embodiment, the diameter of eachconduit 250 is 0.25 mm.
[49] The conduits 250 are arranged longitudinally within the body of the tube 100without intersecting the second slits 110b. In other words, each conduit 250 isaligned along a corresponding longitudinal axis that is different than thelongitudinal axis of the corresponding second slit 110b / set of second slits 110b. Thetube 100 may include equal or different number of second slit 110b / set of secondslits 110b and the conduits 250. The conduits 250 may be positioned along thelongitudinal axis in a regular or an alternating pattern with the longitudinal axis ofthe second slits 110b / set of second slits 110b. The conduit / conduits 250 and thesecond slit / set of second slits 110b, each having a respective longitudinal axis, maybe 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 slits110b, arranged along the longitudinal axis of the tube 100 without following aregular or alternating pattern, with each conduit 250 and each second slit 110boccupying a separate axis. The tube 100 may include an unequal number of conduits250 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 thesecond slits 110b. In the depicted embodiment, the tube 100 includes two sets ofconduits 250 and two sets of second slits 110b. Each set of conduits 250 includesfour conduits 250. Each conduit 250 in the set of conduits 250 are arrangedequidistantly and parallel with each other. Each set of conduits 250 are arranged inan alternating pattern with the sets of second slits 110b.
[52] The conduits 250 within the body of the tube 100 may be formed usingtechniques, such as, without limitations, laser cut, 3D Printing, etc. In an exemplaryembodiment, the conduits 250 within the body ofthe tube 100 is formed using lasercut technique. The conduits 250 provides a passage for the fluid to pass. Eachconduit 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 towardsthe proximal end 100a of the tube 100. In other words, the proximal end 250a ofeach conduit 250 ends in the distal end 300b of the hose 300. The proximal end250a of the conduits 250 receives the fluid from the hose 300. The curved end 250bof each conduit 250 is provided towards the third distal end 200b of the thirdsection 200. The curved end 250b is configured to inject the fluid into the thirdsection 200 at the third distal end 200b, continuously. The continuous injection ofthe fluid is configured to create a high-velocity stream in the flow of the blood andhelps in maintaining a low pressure in the third section 200 than the pressure in thefirst section 160. This prevents backflow of the blood from third section 200 backinto 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 fordelivery of the tube 100. The tube 100 may be delivered at a target site, forexample, an aortic valve, or a pulmonic valve via an appropriate vascular accesspoint. The tube 100 is pre-attached with the hose 300 and is pre-loaded into adelivery catheter or sheath (not shown). During the medical procedure, thecatheter / sheath is routed to the target site with the help of a guidewire (notshown).
[53] In the illustrated embodiment, the catheter / sheath (not shown) is insertedinto the patient's body via the femoral artery in the groin region and is guided upto the heart. Fluoroscopic imaging techniques may be used to guide and monitorthe advancement of the catheter / sheath during the procedure. Once thecatheter / sheath approaches the target site, for example near the aortic valve, thetube 100 is delivered and positioned in the aortic valve, as shown in Fig. 5b. Thefirst section 160 of the tube 100 is positioned within the left ventricle, where bloodis to be received during the ventricular contraction (systole). The second section,including the first tapered portion 182 and the apex 184, is positioned towards theleft ventricle apex. The second tapered portion 186 is positioned in the left ventricleoutflow tract. The third distal end 200b of the third section 200 is positioned justbefore the aortic valve. The third proximal end 200a with the second slits 110b ispositioned within the ascending aorta (beyond the aortic valve), where blood is tobe released.
[54] Once the tube 100 is positioned, the catheter / sheath is retracted, leavingthe tube 100 and the hose 300 inside. The tube 100 remains at the aortic valve. Thehose 300 remains inside of the body of the patient, as shown in Fig. 5a. A proximalportion 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 chambersrelax. The atrioventricular valves (valve between the atria and the left ventricles)remain open. Due to the contraction of the atria, the ventricular chambers receiveblood from the atrial chambers. The left ventricle chamber receives oxygenatedblood from the left atria. The first section 160 in the lumen 140 of the tube 100receives the blood via the first slits 110a. The pump 400 pushes the fluid from thereservoir into the conduits 250 via the hose 300. The conduits 250 pour the fluidinto the third section 200 at the distal third end 180b. The fluid flowing into thethird section 200 maintains a low pressure in the third section 200. As a result, apressure differential is created between the first section 160 and the third section200. Due to the closure of the aortic valve (valve between the left ventricle and theaorta) and the relaxed muscles of the left ventricular chamber, there is a negligibleforce acting upon the blood to push the blood from the first section 160 into thesecond section 180 of the lumen 140. As a result, a vacuum effect is maintainedwithin the second section 180 of the lumen 140 during diastole.
[56] During systole, the atrioventricular valves are closed and the ventriclescontract. Due to the contraction of the ventricles, the blood in the ventricles ispushed into the first section 160 of the lumen 140 in the tube 100 via the first slits110a, as show in Fig. 6. The blood in the first section 160 is further pushed to flowinto the second section 180.
[57] As the blood passes through the second section, the blood experiencesturbulence. The second section 180 is configured to create a venturi effect betweenthe low-pressure region of the first section 160 and the high-pressure region of thethird section 200 within the tube 100. As the blood passes through the first taperedportion 182 of the second section 180, the velocity of blood flowing through thefirst tapered section 182 gradually increases. And, the pressure with which theblood flows across the first tapered portion 182 gradually decreases. This is due tothe gradual decrease in the cross-sectional diameter of the first tapered portion182. The blood then passes through the apex 184 and enters into the secondtapered portion 186 with the highest velocity and the lowest pressure. This is dueto the narrowest cross-sectional diameter of the apex 184 that maximizes thevelocity and the minimizes the pressure of the blood flowing through it. Due to thegradual 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 pump400 pushes the fluid from the fluid reservoir 500 into the conduits 250 via the hose300. 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-velocitystream is created. This high-velocity stream of the fluid further reduces the pressureat the third distal end 200b of the third section 200 in the lumen 140. Thecontinuous injection of the fluid helps in maintaining a low pressure in the thirdsection 200 than the pressure in the first section 160. By maintaining a lowerpressure at the third distal end 200b of the third section 200, a pressure differentialbetween the second portion 180 and the third section 200 remains high, ensuringthe pressure is maintained. This prevents backflow of the blood from third section200 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 beexemplary and that the actual parameters, dimensions, materials, and / orconfigurations will depend upon the specific application or applications for whichthe teachings of the present invention is / are used.
Claims
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).