Description:BACKGROUND
Field of Invention
[001] Embodiments of the present invention generally relate to a stent for vascular interventions and particularly to bioresorbable stent for vascular interventions.
Description of Related Art
[002] Cardiovascular diseases encompass conditions impacting the structures or functionality of the heart and blood vessels. These conditions arise from factors such as smoking, high blood pressure, elevated cholesterol, an unhealthy diet, insufficient exercise, and obesity. The consequences manifest as chest pain, heart attacks, or strokes.
[003] The condition arises from the accumulation of fatty plaques in our arteries, known as atherosclerosis. The atherosclerosis leads to narrowing or obstruction of the blood vessels supplying blood to the heart. Treatment options for the atherosclerosis include medication, surgical procedures such as angioplasty, and participation in cardiac rehabilitation programs. An angioplasty is a medical procedure that deploys a biomedical implant to the site of artery blockage or inflammation. These stents can be designed to either expand arteries or provide treatment for a specific duration. Following implantation, a period is required for the stent to address the blockage or inflammation, after which its continued presence becomes optional.
[004] Following the deployment of these stents, there is a potential for significant thrombus growth between the struts, and the stent material, at times, corrodes the arteries. This situation necessitates bypass surgery, involving the removal of the compromised arteries and replacement with grafts. The primary factors contributing to this issue include the prolonged presence of the stent, its composition, and its design. Additionally, conventional metallic stents are permanently implanted within the artery, offering immediate mechanical support. Furthermore, their extended presence gives rise to complications, including chronic vessel inflammation and the risk of late stent thrombosis.
[005] There is thus a need for an improved and advanced three-dimensional (3D) printed bioresorbable stent for vascular interventions that can administer the aforementioned limitations in a more efficient manner.
SUMMARY
[006] Embodiments in accordance with the present invention provide a three-dimensional (3D) printed bioresorbable stent for vascular interventions. The stent comprising: struts arranged in a pattern to form a structure deployable at a stenotic section within a blood vessel; hoops made up of the struts interconnected to form the structure. The hoops comprise nook and cranny to facilitate a controlled plastic deformation and a radial expansion upon deployment of the stent; an inlet profile comprising a hemispherical elevation at a distal end of the stent to smoothly transition into the stenotic section and minimize flow disruption, and an outlet profile comprising a conical elevation at a proximal end of the stent to facilitate stable anchoring within a vessel lumen and prevent migration of the stent.
[007] Embodiments of the present invention may provide a number of advantages depending on their particular configuration. First, embodiments of the present application may provide a bioresorbable stent for vascular interventions.
[008] Next, embodiments of the present application may provide a bioresorbable stent for vascular interventions that has a good radial strength to provide good post-expansion.
[009] Next, embodiments of the present application may provide a bioresorbable stent for vascular interventions that enable arterial support and have high flexibility for ease of maneuverability during deployment.
[0010] Next, embodiments of the present application may provide a bioresorbable stent for vascular interventions that are free from crimping and resilient to discontinuous compression loads.
[0011] Next, embodiments of the present application may provide a bioresorbable stent for vascular interventions that don’t cause any injury to the artery when it is being expanded.
[0012] Next, embodiments of the present application may provide a bioresorbable stent for vascular interventions that have very good lesion compatibility and give better patient outcomes.
[0013] Next, embodiments of the present application may provide a bioresorbable stent for vascular interventions that promote the growth of endothelial cells and exhibit excellent hemodynamics.
[0014] Next, embodiments of the present application may provide a bioresorbable stent for vascular interventions that is sustainable in design and fabrication.
[0015] Next, embodiments of the present application may a provide a bioresorbable stent for vascular interventions that is customized for every patient.
[0016] Next, embodiments of the present application may a provide a bioresorbable stent for vascular interventions that is designed with optimized dimensions as per the requirement of the patient.
[0017] Next, embodiments of the present application may provide a bioresorbable stent for vascular interventions that use design that ensures mechanical strength, reduces vessel injury, and minimizes restenosis risks.
[0018] Next, embodiments of the present application may provide a bioresorbable stent for vascular interventions that allows for the stent's gradual dissolution over time, eliminating permanent foreign body presence.
[0019] Next, embodiments of the present application may provide a bioresorbable stent for vascular interventions that promotes endothelial cell growth around the stent, fostering natural healing and reducing clot formation.
[0020] Next, embodiments of the present application may provide a bioresorbable stent for vascular interventions that stent's resilience against the dynamic compressive loads of blood vessels further ensures its consistent performance.
[0021] Next, embodiments of the present application may provide a bioresorbable stent for vascular interventions that mitigates long-term complications associated with metallic stents.
[0022] These and other advantages will be apparent from the present application of the embodiments described herein.
[0023] The preceding is a simplified summary to provide an understanding of some embodiments of the present invention. This summary is neither an extensive nor exhaustive overview of the present invention and its various embodiments. The summary presents selected concepts of the embodiments of the present invention in a simplified form as an introduction to the more detailed description presented below. As will be appreciated, other embodiments of the present invention are possible utilizing, alone or in combination, one or more of the features set forth above or described in detail below.
BRIEF DESCRIPTION OF THE DRAWINGS
[0024] The above and still further features and advantages of embodiments of the present invention will become apparent upon consideration of the following detailed description of embodiments thereof, especially when taken in conjunction with the accompanying drawings, and wherein:
[0025] FIG. 1A illustrates a top view of a bioresorbable stent for vascular interventions, according to an embodiment of the present invention;
[0026] FIG. 1B illustrates a front view of the bioresorbable stent for vascular interventions, according to an embodiment of the present invention;
[0027] FIG. 1C illustrates a side view of the bioresorbable stent for vascular interventions, according to an embodiment of the present invention;
[0028] FIG. 1D illustrates an inlet profile of the bioresorbable stent for vascular interventions, according to an embodiment of the present invention;
[0029] FIG. 1E illustrates an outlet profile of the bioresorbable stent for vascular interventions, according to an embodiment of the present invention;
[0030] FIG. 1F illustrates an isometric model of the bioresorbable stent for vascular interventions, according to an embodiment of the present invention; and
[0031] FIG. 1G illustrates a wireframe model of the bioresorbable stent for vascular interventions, according to an embodiment of the present invention.
[0032] The headings used herein are for organizational purposes only and are not meant to be used to limit the scope of the description or the claims. As used throughout this application, the word "may" is used in a permissive sense (i.e., meaning having the potential to), rather than the mandatory sense (i.e., meaning must). Similarly, the words “include”, “including”, and “includes” mean including but not limited to. To facilitate understanding, like reference numerals have been used, where possible, to designate like elements common to the figures. Optional portions of the figures may be illustrated using dashed or dotted lines, unless the context of usage indicates otherwise.
DETAILED DESCRIPTION
[0033] The following description includes the preferred best mode of one embodiment of the present invention. It will be clear from this description of the invention that the invention is not limited to these illustrated embodiments but that the invention also includes a variety of modifications and embodiments thereto. Therefore, the present description should be seen as illustrative and not limiting. While the invention is susceptible to various modifications and alternative constructions, it should be understood, that there is no intention to limit the invention to the specific form disclosed, but, on the contrary, the invention is to cover all modifications, alternative constructions, and equivalents falling within the scope of the invention as defined in the claims.
[0034] In any embodiment described herein, the open-ended terms "comprising", "comprises”, and the like (which are synonymous with "including", "having” and "characterized by") may be replaced by the respective partially closed phrases "consisting essentially of", “consists essentially of", and the like or the respective closed phrases "consisting of", "consists of”, the like.
[0035] As used herein, the singular forms “a”, “an”, and “the” designate both the singular and the plural, unless expressly stated to designate the singular only.
[0036] FIG. 1A illustrates a top view of a bioresorbable stent 100 (hereinafter referred to as the stent 100) for vascular interventions, according to an embodiment of the present invention. In an embodiment of the present invention, the stent 100 may be constructed using a three-dimensional (3D) printing technology. The stent 100 may be constructed of bioresorbable (bio-absorbing) materials that may be, but not limited to, polyurethane, poly(D, L)lactide, poly(lactic-co-glycolic) acid, poly(a-hydroxy acids), cross-linked polyester hydrogels, poly(orthoesters), polyanhydrides, polyethylene glycol, and so forth. Embodiments of the present invention are intended to include or otherwise cover any bioresorbable material for construction of the stent 100, including known, related art, and/or later developed technologies.
[0037] In an embodiment of the present invention, the stent 100 may be fabricated as such for bio-absorption (bioresorbable) inside of the human body. The stent 100 may be surgically implanted to bridge surgically removed arteries and/or veins of the human body. Further, a fresh tissue patch may grow over the stent 100 to bridge a gap created by the surgical removal of arteries and/or veins. However, upon the growth of tissue patch and bridging of the gap created by surgical removal of arteries and/or veins, there may not be any requirement for surgical removal of the stent 100 from the human body, in an embodiment of the present invention.
[0038] In an embodiment of the present invention, the stent 100 may be fabricated and printed using three-dimensional printing technology. The three-dimensional printing technology may utilize Fused Deposition Modelling (FDM) for precise fabrication of the stent 100, in an embodiment of the present invention. The Fused Deposition Modelling (FDM) may be a layer-by-layer printing technique for the three-dimensional (3D) printing technology. The Fused Deposition Modelling (FDM) may utilize thermoplastic materials, that may further be extruded through a nozzle tip (not shown) while being heated to a semi-molten state and then deposited onto the substrate, leaving behind the three-dimensional print model object when thermoplastic material may have been solidified.
[0039] In another embodiment of the present invention, the three-dimensional printing technology for the fabrication of the stent 100 may be stereolithography (SLA), Selective Laser Sintering (SLS), Electron Beam Melting (EBM), and so forth. Embodiments of the present invention are intended to include or otherwise cover any three-dimensional printing technology for the construction of the stent 100, including known, related art, and/or later developed technologies. Further, the stent 100 may be optimized using topology optimization techniques. The topology optimization technique may be a shape optimization method that uses algorithmic models to optimize material layout within a user-defined space for a given set of loads, conditions, and constraints.
[0040] In an embodiment of the present invention, the stent 100 may be printed in a reinforcing lattice structure within the implant profile to bolster compressional load resilience and bone growth during degradation.
[0041] Further, upon completion of printing of the stent 100, the stent 100 may be submersed in a Simulated Body Fluid (SBF) for a preset duration of time to maintain a pH of 7.4. The Simulated Body Fluid (SBF) may be a solution with an iron concentration close to that of a human blood plasma, in an embodiment of the present invention. In an embodiment of the present invention, the Simulated Body Fluid (SBF) may be kept under mild conditions of pH and identical physiological temperature as of the human body.
[0042] In an embodiment of the present invention, the use of bioresorbable polymers for the construction of the stent 100, as opposed to traditional metals may be groundbreaking. The bioresorbable polymers used for the construction of the stent 100 may dissolve over time, eliminating any permanent foreign structure in the vessel, thus potentially minimizing long-term complications.
[0043] According to embodiments of the present invention, the stent 100 comprises struts 102a-102n (hereinafter referred individually to as the strut 102, and plurally to as the struts 102), hoops 104a-104n (hereinafter referred individually to as the hoop 104, and plurally to as the hoops 104), linking elements 106a-106n (hereinafter referred individually to as the linking element 106, and plurally to as the linking elements 106), an inlet profile 108, a hemispherical elevation 110, an outlet profile 112, and a conical elevation 114.
[0044] In an embodiment of the present invention, the stent 100 may be deployed at a deployment diameter at a stenotic section of a blood vessel. The stent 100 may comprise a scaffolding, in an embodiment of the present invention. In an embodiment of the present invention, the scaffolding may be composed of the struts 102, and the struts 102 may further comprise the hoops 104 connected by the linking elements 106.
[0045] In an embodiment of the present invention, the struts 102 may be arranged in a pattern to form a structure deployable at a stenotic section within the blood vessel. The hoops 104 may be made up of the struts 102 interconnected to form the structure, in an embodiment of the present invention.
[0046] In an embodiment of the present invention, the struts 102 may be designed with attention to detail. The struts 102 may be optimized for a thickness of the struts 102, a width of the struts 102, and a length of the struts 102. The optimization of the struts 102 may ensure mechanical robustness and superior interactions with surrounding blood flow, reducing restenosis risks.
[0047] In an embodiment of the present invention, the hoops 104 may comprise with nook and cranny to facilitate a controlled plastic deformation and a radial expansion upon deployment of the stent 100. Further, the hoops 104 may be made up of the struts 102 interlinked with the nook and the cranny. The struts 102 may bend to cause plastic deformation at the nook and the cranny when the stent 100 is deployed to the deployment diameter.
[0048] According to embodiments of the present invention, a width of the struts 102 may be in a range from 01.24 millimeters (mm) to 01.55 millimeters (mm). Embodiments of the present invention are intended to include or otherwise cover any width of the struts 102 of the stent 100.
[0049] FIG. 1B illustrates a front view of the stent 100, according to an embodiment of the present invention. According to embodiments of the present invention, a length of the stent 100 may be in the range from 15.00 millimeters (mm) to 16.00 millimeters (mm). In a preferred embodiment of the present invention, the length of the stent 100 may be 15.53 millimeters (mm). Embodiments of the present invention are intended to include or otherwise cover any length of the stent 100.
[0050] In an embodiment of the present invention, all the sharp edges of the stent 100 may be rounded to give smoother adhesion to the vessel wall so that no itching sensation may be felt under discontinuous compression loads. The stent 100 may have a high coverage percentage that may be closely related to the restenosis rate. The stent 100 may have a smooth surface finish with a flat cubic elevation to improve endothelial adhesion.
[0051] In this embodiment of the present invention, the strut 102 of the stent 100 is designed to have a specific profile aimed at diminishing both principal stress and maximum principal strain. This reduction may be facilitated by an enhanced mass distribution across the width of the strut. The stent 100 may be equipped with the strut 102 having a thinner profile in unstressed areas to prevent endoluminal paving, in an embodiment of the present invention. In another embodiment of the present invention, the strut 102 may be having a thicker profile in stressed areas. The variation in the profile thickness may help in preventing a breakage of the strut 102.
[0052] The inlet profile 102 of the stent 100 may be curvier so that the entry of blood may be smoother, and the exit may be the same with the remaining struts 102 of the stent 100. The stent 100 may prevent formation of thrombus at vessel walls. The stent 100 may enable the optimization of the final blood flow profile.
[0053] FIG. 1C illustrates a side view of the stent 100, according to an embodiment of the present invention. According to embodiments of the present invention, an external diameter of the stent 100 may be in the range from 01.06 millimeters (mm) to 01.30 millimeters (mm). Embodiments of the present invention are intended to include or otherwise cover any external diameter of the stent 100. According to embodiments of the present invention, an internal diameter of the stent 100 may be in the range from 00.01 millimeters (mm) to 00.03 millimeters (mm). In a preferred embodiment of the present invention, the internal diameter of the stent 100 may be 00.02 millimeters (mm). Embodiments of the present invention are intended to include or otherwise cover any internal diameter of the stent 100.
[0054] FIG. 1D illustrates the inlet profile 108 of the stent 100, according to an embodiment of the present invention. In an embodiment of the present invention, the inlet profile 108 may comprise the hemispherical elevation 110 at a distal end of the stent 100. The hemispherical elevation 110 may enable a smooth transition of the stent 100 into the stenotic section and may minimize a flow disruption, in an embodiment of the present invention. According to embodiments of the present invention, the hemispherical elevation 110 of the inlet profile 108 of the stent 100 may be in the range from 00.05 millimeters (mm) to 00.07 millimeters (mm). In a preferred embodiment of the present invention, the hemispherical elevation 110 of the inlet profile 108 of the stent 100 may be 00.06 millimeters (mm). Embodiments of the present invention are intended to include or otherwise cover any hemispherical elevation 110 of the inlet profile 108 of the stent 100.
[0055] FIG. 1E illustrates the outlet profile 112 of the stent 100, according to an embodiment of the present invention. In an embodiment of the present invention, the outlet profile 112 may comprise the conical elevation 114 at a proximal end of the stent 100. The conical elevation 114 of the outlet profile 112 may facilitate stable anchoring within the vessel lumen and prevent migration of the stent 100, in an embodiment of the present invention. According to embodiments of the present invention, the conical elevation 114 of the outlet profile 112 of the stent 100 may be in the range from 00.01 millimeters (mm) to 00.03 millimeters (mm). In a preferred embodiment of the present invention, the conical elevation 114 of the outlet profile 112 of the stent 100 may be 00.02 millimeters (mm). Embodiments of the present invention are intended to include or otherwise cover any conical elevation 114 of the outlet profile 112 of the stent 100.
[0056] FIG. 1F illustrates an isometric model 116 of the stent 100, according to an embodiment of the present invention.
[0057] FIG. 1G illustrates a wireframe model 118 of the stent 100, according to an embodiment of the present invention.
[0058] While the invention has been described in connection with what is presently considered to be the most practical and various embodiments, it is to be understood that the invention is not to be limited to the disclosed embodiments, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the scope of the appended claims.
[0059] This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined in the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements within substantial differences from the literal languages of the claims. , Claims:CLAIMS
I/We Claim:
1. A bioresorbable stent (100) for vascular interventions, printable using a three-dimensional technique, the stent (100) comprising:
struts (102a-102n) arranged in a pattern to form a structure deployable at a stenotic section within a blood vessel;
hoops (104a-104n) made up of the struts (102a-102n) that are interconnected to form the structure, wherein the hoops (104a-104n) comprise nook and cranny to facilitate a controlled plastic deformation and a radial expansion upon deployment of the stent (100);
an inlet profile (108) comprising a hemispherical elevation (110) at a distal end of the stent (100) to smoothly transition into the stenotic section and minimize flow disruption, and
an outlet profile (112) comprising a conical elevation (114) at a proximal end of the stent (100) to facilitate stable anchoring within a vessel lumen and prevent a migration of the stent (100).
2. The stent (100) as claimed in claim 1, wherein a width of each of the struts (102a-102n) is in a range from 01.24 millimeters (mm) to 01.55 millimeters (mm).
3. The stent (100) as claimed in claim 1, wherein a model of the stent (100) is selected from an isometric model (116), a wireframe model (118), or a combination thereof.
4. The stent (100) as claimed in claim 1, wherein the three-dimensional (3D) printing technology is a Fused Deposition Modelling (FDM).
5. The stent (100) as claimed in claim 1, wherein the stent (100) is constructed using bioresorbable materials selected from polyurethane, poly(D, L)lactide, poly(lactic-co-glycolic) acid, poly(a-hydroxy acids), cross-linked polyester hydrogels, poly(orthoesters), polyanhydrides, polyethylene glycol, or a combination thereof.
6. The stent (100) as claimed in claim 1, wherein an external diameter of the stent (100) is in a range from 01.06 millimeters (mm) to 01.30 millimeters (mm).
7. The stent (100) as claimed in claim 1, wherein an internal diameter of the stent (100) is 00.02 millimeters (mm).
8. The stent (100) as claimed in claim 1, wherein a length of the stent (100) is 15.53 millimeters (mm).
9. The stent (100) as claimed in claim 1, wherein the hemispherical elevation (110) is 00.06 millimeters (mm).
10. The stent (100) as claimed in claim 1, wherein the conical elevation (114) is 00.02 millimeters (mm).
Date: March 01, 2024
Place: Noida

Dr. Keerti Gupta
Agent for the Applicant
(IN/PA-1529)