Bifurcated stent and method of making

A longitudinally flexible Y-shaped stent for implanting in a bifurcated body lumen, comprising:

• a plurality of cylindrical elements that are independently expandable in the radial direction and that are interconnected so as to be generally aligned on a common longitudinal axis;
• a plurality of connecting elements for interconnecting the cylindrical elements, the connecting elements configured to interconnect only the cylindrical elements that are adjacent to each other;
• and
• an outer wall surface on the cylindrical elements, the outer wall surface being smooth prior to expansion of the Y-shaped stent and forming a plurality of outwardly projecting edges that form as the stent is expanded radially outwardly from a first diameter to a second, enlarged diameter, wherein the Y-shaped stent has a proximal end and a distal end in communication with each other, the proximal end including a generally cylindrical proximal branch having a proximal end and a distal end and the distal end including a first generally cylindrical distal branch and a second generally cylindrical distal branch, the first distal branch and second distal branch defined by a proximal end and a distal end and a series of expandable cylindrical elements and pivotally attached to a plurality of bending elements that extend between cylindrical elements at the proximal end of each distal branch to form a carina junction, thus defining an angle of varying degree such that the carina junction extends proximal the proximal end of each distal branch, each of the plurality of bending elements extending from the same cylindrical element within each distal branch, and wherein the first and second distal branches are attached to the proximal branch proximal the carina junction.

A method of making an expandable metal Y-shaped stent, comprising the steps of:

• providing a first metal tube;
• providing a second metal tube;
• forming a proximal stent section out of the first metal tube and a distal stent section out of the second metal tube, the distal stent section having a first distal branch and a second distal branch;
• wherein the first distal branch and the second distal branch are connected by bending elements thereby forming a carina junction;
• and
• forming at least one of male struts and female struts in the first tube and at least one of male struts and female struts in the second tube such that decreasing the angle between the distal branches serves to cause the at least one of male struts and female struts formed in the second tube to bend outwardly to facilitate attachment of the first tube to the second tube, the male struts and female struts including one of a fork configuration, a ball and socket configuration, a butt configuration, and a lap joint configuration.