US-12616592-B2 - Bidirectional stent and method of use thereof

US12616592B2US 12616592 B2US12616592 B2US 12616592B2US-12616592-B2

Abstract

A bidirectional twistable stent is disclosed. The stent comprises a cylinder-shaped stent body having a plurality of axially arranged rows of struts encircling a central lumen and a plurality of flex connectors that connect at least two adjacent rows of struts in such a manner that allows the stent to be twisted clockwise or counter clockwise without causing deformation of any struts in the stent body. Also disclosed are the method of making the stent, method of using the stent, and a kit containing the stent.

Inventors

Eric K. Mangiardi

Assignees

Q3 MEDICAL DEVICES LIMITED

Dates

Publication Date: 20260505
Application Date: 20231031

Claims (14)

1 . A method of using a bidirectional stent, comprising the step of: placing the bidirectional stent in a treatment site in a compressed state; and enlarging the bidirectional stent to an expanded state at the treatment site to immobilize the bidirectional stent, wherein the bidirectional stent comprises: a cylinder-shaped stent body comprising a plurality of axially arranged rows of struts encircling a central lumen and a plurality of axially arranged alternating rows of s-shaped connectors and rows of opposite s-shaped connectors encircling the central lumen, wherein openings are between each of the s-shaped connectors arranged in alternating rows, and wherein each row of s-shaped connectors is flanked on both sides by rows of opposite s-shaped connectors and each row of opposite s-shaped connectors is flanked on both sides by rows of s-shaped connectors, wherein each of the rows of struts consists of struts inter-connected to form a wave-pattern with alternating peaks and troughs, wherein each peak has a tip and each trough has a bottom, wherein each peak in a row of struts is connected at its tip to a peak at its tip in an adjacent row of struts by an s-shaped connector or opposite s-shaped connector, wherein the s-shaped connectors in the same row of the s-shaped connectors have the same configuration, and wherein when the bidirectional stent is in a resting state, each peak in each row of struts is attached to one end of an s-shaped connector or an opposite s-shaped connector that is attached at its other end to a facing peak of an adjacent row with the facing peak being at an angle to the each peak, and each of the s-shaped connectors or opposite s-shaped connectors has a body having a continuous curve with an inflexion point, and wherein when the bidirectional stent is subject to twist, the rows of s-shaped connectors and opposite s-shaped connectors contract or expand in an alternating manner to form a peristaltic shape in the stent body, and the rows of s-shaped connectors or opposite s-shaped connectors that are contracting form a neck shape, and the rows of s-shaped connectors or opposite s-shaped connectors that are expanding form a peristaltic shape, and the neck shape has a lesser radius than the radius of the peristaltic shape at its greatest expanse, thus allowing the stent body to be reversibly twisted clockwise or counter-clockwise from one end of the stent body by a full turn without causing permanent deformation of the struts and the s-shaped connectors or opposite s-shaped connectors in the stent body.
2 . The method of claim 1 , wherein each of the s-shaped connectors in the bidirectional stent has a length that is about 150% to 500% of the larger of the row width of the two rows of struts that are connected by the s-shaped connectors.
3 . The method of claim 1 , wherein each of the s-shaped connectors in the bidirectional stent has a length that is about 300% of the larger of the row width of the two rows of struts that are connected by the s-shaped connectors.
4 . The method of claim 1 , wherein the stent body of the bidirectional stent is covered with a biodegradable coating.
5 . The method of claim 4 , wherein the biodegradable coating comprises chitosan.
6 . A method for making a bidirectional stent, comprising: slitting a cylinder-shaped tube with a laser to create a matrix of struts and connectors that form the bidirectional stent, wherein the bidirectional stent comprises: a cylinder-shaped stent body comprising a plurality of axially arranged rows of struts encircling a central lumen and a plurality of axially arranged alternating rows of s-shaped connectors and rows of opposite s-shaped connectors encircling the central lumen, wherein openings are between each of the s-shaped connectors arranged in alternating rows, and wherein each row of s-shaped connectors is flanked on both sides by rows of opposite s-shaped connectors and each row of opposite s-shaped connectors is flanked on both sides by rows of s-shaped connectors, wherein each of the rows of struts consists of struts inter-connected to form a wave-pattern with alternating peaks and troughs, wherein each peak has a tip and each trough has a bottom, wherein each peak in a row of struts is connected at its tip to a peak at its tip in an adjacent row of struts by an s-shaped connector or opposite s-shaped connector, wherein the s-shaped connectors in the same row of the s-shaped connectors have the same configuration, and wherein when the bidirectional stent is in a resting state, each peak in each row of struts is attached to one end of an s-shaped connector or an opposite s-shaped connector that is attached at its other end to a facing peak of an adjacent row with the facing peak being at an angle to the each peak, and each of the s-shaped connectors or opposite s-shaped connectors has a body having a continuous curve with an inflexion point, and wherein when the bidirectional stent is subject to twist, the rows of s-shaped connectors and opposite s-shaped connectors contract or expand in an alternating manner to form a peristaltic shape in the stent body, and the rows of s-shaped connectors or opposite s-shaped connectors that are contracting form a neck shape, and the rows of s-shaped connectors or opposite s-shaped connectors that are expanding form a peristaltic shape, and the neck shape has a lesser radius than the radius of the peristaltic shape at its greatest expanse, thus allowing the stent body to be reversibly twisted clockwise or counter-clockwise from one end of the stent body by a full turn without causing permanent deformation of the struts and the s-shaped connectors or opposite s-shaped connectors in the stent body.
7 . The method of claim 6 , wherein each of the s-shaped connectors in the bidirectional stent has a length that is about 150% to 500% of the larger of the row width of the two rows of struts that are connected by the s-shaped connectors.
8 . The method of claim 7 , wherein each of the s-shaped connectors in the bidirectional stent has a length that is about 300% of the larger of the row width of the two rows of struts that are connected by the s-shaped connectors.
9 . The method of claim 7 , wherein the cylinder-shaped tube is made from a metal or an alloy.
10 . The method of claim 7 , wherein the cylinder-shaped tube is made from nitinol.
11 . The method of claim 7 , further comprising the step of coating the matrix of struts and connectors with a biodegradable polymer coating.
12 . The method of claim 11 , wherein the biodegradable polymer coating comprises chitosan.
13 . A stent kit, comprising: (1) a bidirectional stent that comprises: a cylinder-shaped stent body comprising a plurality of axially arranged rows of struts encircling a central lumen and a plurality of axially arranged alternating rows of s-shaped connectors and rows of opposite s-shaped connectors encircling the central lumen, wherein openings are between each of the s-shaped connectors arranged in alternating rows, and wherein each row of s-shaped connectors is flanked on both sides by rows of opposite s-shaped connectors and each row of opposite s-shaped connectors is flanked on both sides by rows of s-shaped connectors, wherein each of the rows of struts consists of struts inter-connected to form a wave-pattern with alternating peaks and troughs, wherein each peak has a tip and each trough has a bottom, wherein each peak in a row of struts is connected at its tip to a peak at its tip in an adjacent row of struts by an s-shaped connector or opposite s-shaped connector, wherein the s-shaped connectors in the same row of the s-shaped connectors have the same configuration, and wherein when the bidirectional stent is in a resting state, each peak in each row of struts is attached to one end of an s-shaped connector or an opposite s-shaped connector that is attached at its other end to a facing peak of an adjacent row with the facing peak being at an angle to the each peak, and each of the s-shaped connectors or opposite s-shaped connectors has a body having a continuous curve with an inflexion point, and wherein when the bidirectional stent is subject to twist, the rows of s-shaped connectors and opposite s-shaped connectors contract or expand in an alternating manner to form a peristaltic shape in the stent body, and the rows of s-shaped connectors or opposite s-shaped connectors that are contracting form a neck shape, and the rows of s-shaped connectors or opposite s-shaped connectors that are expanding form a peristaltic shape, and the neck shape has a lesser radius than the radius of the peristaltic shape at its greatest expanse, thus allowing the stent body to be reversibly twisted clockwise or counter-clockwise from one end of the stent body by a full turn without causing permanent deformation of the struts and the s-shaped connectors or opposite s-shaped connectors in the stent body; and (2) instructions for using the bidirectional stent.
14 . The kit of claim 13 , further comprising a guidewire.

Description

This application is a Continuation of U.S. application Ser. No. 15/638,599, which is a Continuation of U.S. application Ser. No. 15/165,917, filed May 26, 2026, now U.S. Pat. No. 9,750,624, which is a Continuation of U.S. application Ser. No. 14/163,728, filed Jan. 24, 2014. Now U.S. Pat. No. 9,375,810. The entirety of the aforementioned application is incorporated herein by reference. FIELD The present application relates generally to medical devices and, in particular, to a stent implantable into a body cavity and method for implanting same. BACKGROUND An in vivo supporting device or barrier device, such as a stent, is a man-made “tube” or “frame” inserted into a natural passage or conduit in the body to prevent, or counteract, a disease-induced, localized flow constriction or flow outflow like a leak or aneurysm. Supporting stents include vascular supporting stents, non-vascular supporting stents, and aneurysm sealing stents. Vascular supporting stents are designed for applications in the vascular system, such as arteries and veins. Non-vascular supporting stents are used in other body lumens such as biliary, colorectal, esophageal, ureteral and urethral tract, and upper airway. Aneurysm sealing stents are used to close off potentially dangerous aneurysms or pseudo aneurysms throughout the vascular and non-vascular system. Percutaneous transluminal angioplasty (PTA) has evolved over the past 20 years to become a common therapeutic technique for the treatment of peripheral vascular disease. Self-expanding stents are delivered to a desired site mounted onto a stent delivery catheter and are held in place on the catheter by an outer cover until the stent has reached the deployment site. The outer cover is retracted and the stent expands off the catheter to contact the walls of the lumen, where it is held in place by the chronic outward pressure of the stent against the walls of the lumen. There are several problems with self-expanding stents currently on the market, including the fact that their design takes into account only their expansion at the site of deployment, without regard to the twisting and bending that the stent must do to navigate blood vessels on the way to the deployment site, which can cause the stent to collapse, resulting in damage to the stent that impairs proper deployment. Additionally, there exists the possibility of the stent foreshortening, displacing or jumping during deployment, causing the stent to be emplaced improperly, requiring removal of the stent and replacement with another. Therefore, there is an existing need for a self-expanding stent that, irrespective of the insertion site, is capable of enduring the twisting inherent in the delivery process and that evenly expands at the deployment site without foreshortening. SUMMARY One aspect of the present application relates to a bidirectional stent, comprising: (1) a cylinder-shaped stent body comprising a plurality of axially arranged rows of struts encircling a central lumen, wherein each of said rows of struts comprises struts inter-connected to form a wave-pattern with alternating peaks and troughs, wherein each peak has a tip and each trough has a bottom, and wherein said rows of struts form one or more row sections and wherein each row section comprises at least one row of struts; (2) non-flex connectors that connect adjacent rows of struts within each row section, wherein each of said non-flex connectors comprises a first end and a second end, wherein said first end is attached to a tip of a peak in a first row of struts, wherein said second end is attached to a tip of a peak in a second row of struts, wherein said first row of struts and said second row of struts are within the same row section and are adjacent to each other, and wherein no non-flex connector is present in a row section containing only one row of struts; and (3) flex connectors that connect adjacent row sections, wherein each of said flex connectors comprises a first end and a second end, wherein said first end is attached to a bottom of a first trough in an edge row of struts of a first row section, said first trough has a first trough amplitude, wherein said second end is attached to a bottom of a second trough in an edge row of struts of a second row section, said second trough has a second trough amplitude, wherein said first row section is adjacent to said second row section, and wherein said stent body is capable of being twisted clockwise or counter-clockwise from one end of said stent body by one-fourth of a turn, or more, without causing deformation of struts and connectors in said stent body. Another aspect of the present application relates to a bidirectional stent, comprising: (1) a cylinder-shaped stent body comprising a plurality of axially arranged rows of struts encircling a central lumen, wherein each of said rows of struts comprises struts inter-connected to form a wave-pattern with alternating peaks and troughs, wherein each peak has