Stent delivery system

A stent delivery system comprising:

• a catheter comprising an expansible distal portion constructed and arranged for expanding the outer diameter of said catheter from a contracted state to an expanded state,
• a stent positioned around said distal portion of said catheter, said stent having a contracted condition and being expansible to an expanded condition, and being sized in said contracted condition to closely surround said catheter in the contracted state, said stent having a first and second end portion defining a first and second margin lying over said expansible portion of said catheter,
• a first and second sleeve in the region of said distal portion of said catheter positioned around said catheter, each having a first end fixed to said catheter and a second end defining a margin lying over a said margin of said stent,
• said first sleeve and said second sleeve separately engaging said stent at said first margin and said second margin respectively;
• said first and second sleeve fixing said ends of said stent on said catheter when said catheter is in the contracted state, said catheter and stent cooperatively constructed or arranged to cause expansion of said catheter from said contracted state to said expanded state to cause expansion of said stent, including said first and second margin of said stent, from said contracted condition to said expanded condition, and therewith cause said first and second margins of said sleeve to slide relatively axially from over the margins of said first and second stent, thereby simultaneously releasing said ends of the stent from said catheter.

A method for fastening a stent to a catheter in a manner suitable for facilitating introduction, and later release, of said stent into a body cavity, comprising the steps of:

• (a) providing a catheter having an expansible distal portion constructed and arranged for expanding the outer diameter of said catheter, said distal portion an expanded and a contracted state;
• (b) providing a stent having an expanded and a contracted condition;
• (c) sliding said stent axially over said catheter in the contracted state and about said distal
• (d) providing a sleeve in an expanded form, said sleeve also having a contracted form;
• (e) sliding said expanded sleeve axially over said catheter and about a portion of said stent;
• and
• (f) allowing said sleeve to contract about said catheter and said stent and thereby fix said stent to said catheter when said catheter and said stent are in their contracted state or condition;
• said catheter and stent cooperating whereby said sleeve is released from said stent when said catheter is in its expanded state and said stent is in its expanded condition.