Braided stent with expansion ring and method of delivery

An apparatus for delivering and releasing a self-expanding braided stent through a delivery sheath to a treatment site in a patient's vasculature, said apparatus comprising:

• a tubular self-expanding braided stent body having a proximal end, a distal end, and an inner lumen, said tubular self-expanding braided stent body being formed from a plurality of elongate members, said tubular self-expanding braided stent body having a compressed configuration and an expanded configuration;
• at least one expansion ring disposed within and fixedly connected to said distal end of said tubular braided stent body, said at least one expansion ring having a first end, a second end, and an inner lumen, said at least one expansion ring having a compressed configuration having a first diameter and an expanded configuration having a second diameter larger than said first diameter, said at least one expansion ring including a plurality of elongated connecting arm members having first ends at said first end of said at least one expansion ring and second ends at said second end of said expansion ring, said plurality of elongated connecting arm members being connected sequentially to adjacent ones of said plurality of elongated connecting arm members alternatingly at said first and second ends to form a plurality of alternating elbow connections at said first and second ends having a zigzag configuration, wherein said plurality of elongated connecting arm members and said alternating elbow connections are configured to be compressed into a small tubular shape during delivery;
• a core advancement wire disposed within and extending through said lumen of said tubular braided stent body and said lumen of said expansion ring, said core advancement wire having a proximal portion, a distal portion, an intermediate portion located between said proximal and distal portions of said core advancement wire, and a distal stop member positioned between said distal portion and said intermediate portion of said core advancement wire, said stop member being configured to engage a proximal, interior side of said at least one expansion ring when the said core advancement wire is advanced distally, whereby force applied distally to said core advancement wire is transmitted through said at least one expansion ring to said distal end of said tubular self-expanding braided stent body and acts to drag and elongate said tubular self-expanding braided stent body, and wherein said core advancement wire is configured to reduce friction of said tubular self-expanding braided stent body with said delivery sheath when force is applied distally to said core advancement wire.

An apparatus for delivering and releasing a self-expanding stent through a delivery sheath to a treatment site in a patient's vasculature, said apparatus comprising:

• a tubular self-expanding braided stent body having a proximal end, a distal end, and an inner lumen, said tubular self-expanding braided stent body being formed from a plurality of elongate members, said tubular self-expanding braided stent body having a compressed configuration and an expanded configuration;
• a distal expansion ring and a proximal expansion ring, said distal expansion ring disposed within and fixedly connected to said distal end of said tubular self-expanding braided stent body, said proximal expansion ring disposed within and fixedly connected to said proximal end of said tubular self-expanding braided stent body, each of said distal and proximal expansion rings having a first end, a second end, and an inner lumen, each of said distal and proximal expansion rings having a compressed configuration having a first diameter and an expanded configuration having a second diameter larger than said first diameter, each of said distal and proximal expansion rings including a plurality of elongated connecting arm members having first ends at said first end of said at least one expansion ring and second ends at said second end of said expansion ring, said plurality of elongated connecting arm members being connected sequentially to adjacent ones of said plurality of elongated connecting arm members alternatingly at said first and second ends to form a plurality of alternating elbow connections at said first and second ends having a zigzag configuration, wherein said plurality of elongated connecting arm members and said alternating elbow connections are configured to be compressed into a small tubular shape during delivery;
• a core advancement wire disposed within and extending through said lumen of said tubular self-expanding braided stent body and said lumen of said expansion ring, said core advancement wire having a proximal portion, a distal portion, an intermediate portion located between said proximal and distal portions of said core advancement wire, a distal stop member positioned between said distal portion and said intermediate portion of said core advancement wire, and an intermediate stop member on said core advancement wire positioned on said intermediate portion of said core advancement wire within said lumen of said tubular self-expanding braided stent body distal to said second expansion ring, said distal stop member being configured to engage a proximal, interior side of said at least one expansion ring when the said core advancement wire is advanced distally, whereby force applied distally to said core advancement wire is transmitted through said at least one expansion ring to said distal end of said tubular self-expanding braided stent body and acts to drag and elongate said tubular self-expanding braided stent body, and wherein said core advancement wire is configured to reduce friction of said tubular self-expanding braided stent body with said delivery sheath when force is applied distally to said core advancement wire, and said intermediate stop member being configured to engage a distal, interior side of said proximal expansion ring when said core advancement wire is retracted proximally, allowing retraction of said tubular self-expanding braided stent body within the delivery sheath.

A method of delivering and releasing a self-expanding braided stent through a delivery sheath to a treatment site in a patient's vasculature, comprising the steps of:

• providing a tubular self-expanding braided stent body having an initial deployment end, an inner lumen, and an expansion ring disposed within and fixedly connected to said initial deployment end of said tubular braided stent body, said tubular self-expanding braided stent body having a compressed configuration and an expanded configuration, and said expansion ring having a first end, a second end, an inner lumen, a compressed configuration having a first diameter and an expanded configuration having a second diameter larger than said first diameter, and a core advancement wire disposed within and extending through said lumen of said tubular braided stent body and said lumen of said expansion ring, said core advancement wire having a proximal portion, a distal portion, an intermediate portion located between said proximal and distal portions of said core advancement wire, and a distal stop member positioned between said distal portion and said intermediate portion of said core advancement wire;
• and
• advancing said core advancement wire longitudinally such that said distal stop member engages a proximal, interior side of said expansion ring, whereby force applied longitudinally to said core advancement wire is transmitted through said expansion ring to said initial deployment end of said tubular self-expanding braided stent body acting to drag and elongate said tubular self-expanding braided stent body, reducing friction of said tubular self-expanding braided stent body with said delivery sheath when force is applied longitudinally to said core advancement wire.

A method of delivering and releasing a self-expanding braided stent through a delivery sheath to a treatment site in a patient's vasculature, comprising the steps of:

• providing a tubular self-expanding braided stent body having a proximal end, a distal end, an inner lumen, and a distal expansion ring and a proximal expansion ring, said distal expansion ring disposed within and fixedly connected to said distal end of said tubular self-expanding braided stent body, said proximal expansion ring disposed within and fixedly connected to said proximal end of said tubular self-expanding braided stent body, said tubular self-expanding braided stent body having a compressed configuration and an expanded configuration, each of said distal and proximal expansion rings having a first end, a second end, and an inner lumen, each of said distal and proximal expansion rings having a compressed configuration having a first diameter and an expanded configuration having a second diameter larger than said first diameter, and a core advancement wire disposed within and extending through said lumen of said tubular braided stent body, said lumen of said distal expansion ring, and said lumen of said proximal expansion ring, said core advancement wire having a proximal portion, a distal portion, an intermediate portion located between said proximal and distal portions of said core advancement wire, a distal stop member positioned between said distal portion and said intermediate portion of said core advancement wire and an intermediate stop member on said core advancement wire positioned on said intermediate portion of said core advancement wire within said lumen of said tubular self-expanding braided stent body distal to said proximal expansion ring;
• advancing said core advancement wire distally such that said distal stop member engages a proximal, interior side of said distal expansion ring, whereby force applied distally to said core advancement wire is transmitted through said distal expansion ring to said distal end of said tubular self-expanding braided stent body to drag and elongate said tubular self-expanding braided stent body;
• dragging said distal expansion member of said tubular self-expanding braided stent body distally of said delivery sheath while retaining said proximal expansion member of said tubular self-expanding braided stent body within said delivery sheath;
• retracting said core advancement wire proximally such that said intermediate stop member engages a distal, interior side of said proximal expansion ring;
• and
• retracting said distal end of said tubular self-expanding braided stent body within said delivery sheath such that said distal expansion member and said distal end of said tubular self-expanding braided stent body are reduced in diameter;
• and
• recapturing said tubular self-expanding braided stent body within said delivery sheath.