Bioabsorbable Polymeric Medical Device

Abstract

In embodiments there is described a cardiovascular tube-shaped lockable and expandable bioabsorbable scaffold having a low immunogenicity manufactured from a crystallizable bioabsorbable polymer composition or blend.

1 . A bioabsorbable and flexible scaffold circumferential about a longitudinal axis so as to form a tube, said tube having a proximal open end and a distal open end, and being expandable from an unexpanded form to an expanded form, and being crimpable, said scaffold having a patterned shape in expanded form comprising:
 a) a plurality of first meandering strut patterns, each of said first meandering strut pattern being interconnected to one another to form an interconnected mesh pattern circumferential about said longitudinal axis, and   b) at least two second strut patterns nested within said interconnected mesh pattern, each of said second strut patterns comprising a hoop circumferential about said longitudinal axis, said hoop having an inner surface proximal to said longitudinal axis and an outer surface distal to said longitudinal axis, said hoop inner and outer surfaces about their circumferences being orthogonal to said longitudinal axis and within substantially the same plane.   
   
   
       2 . The scaffold of  claim 1 , wherein said first meandering strut patterns are generally parallel to said longitudinal axis. 
   
   
       3 . The scaffold of  claim 1 , wherein said first meandering strut patterns are generally diagonal to said longitudinal axis. 
   
   
       4 . The scaffold of  claim 1 , wherein said first meandering strut patterns are generally orthogonal to said longitudinal axis. 
   
   
       5 . The scaffold of  claim 1 , wherein said first meandering strut patterns are concentric about said longitudinal axis. 
   
   
       6 . The scaffold of  claim 1 , wherein said second strut patterns are made of a material which substantially crystallizes when said tube is in its expanded state, but does not substantially crystallize in its unexpanded state. 
   
   
       7 . The scaffold of  claim 1 , wherein said second strut patterns include in at least one hoop a through-void. 
   
   
       8 . The scaffold of  claim 7 , wherein said through-void is configured to permit the radius of said at least one hoop to be expanded when said at least one hoop is subject to an expanding force which exceeds its nominal expanded state but does not result in hoop failure. 
   
   
       9 . The scaffold of  claim 1 , wherein each of said first meandering strut patterns is sinusoidal. 
   
   
       10 . The scaffold of  claim 9 , wherein each of said second strut patterns is substantially non-sinusoidal. 
   
   
       11 . The scaffold of  claim 1 , wherein each of said first meandering strut patterns extends from said proximal open end to said distal open end of said tube. 
   
   
       12 . The scaffold of  claim 11 , wherein each of said second strut patterns is found at said proximal open end and said distal open end. 
   
   
       13 . The scaffold of  claim 12 , wherein each of said second strut patterns is further found between said proximal open end and said distal open end. 
   
   
       14 . The scaffold of  claim 11 , wherein each of said second strut patterns is found between said proximal open end and said distal open end but not at the proximal open end or distal open end. 
   
   
       15 . The scaffold of  claim 11 , wherein said second strut pattern is found at least at one of said proximal open end or said distal open end. 
   
   
       16 . A stent having an unexpanded configuration and an expanded configuration; an outer tubular surface and an inner tubular surface, said stent comprising:
 a plurality of biodegradable, paired, separate circumferential bands having a pattern of distinct undulations in an unexpanded configuration and substantially no undulations in an expanded configuration, said undulations of said biodegradable, paired, separate circumferential bands in said stent in an unexpanded state being incorporated into a substantially planar ring in an expanded state; and   a plurality of biodegradable interconnection structures spanning between each pair of circumferential bands and connected to multiple points on each band of said paired bands.   
   
   
       17 . The stent of  claim 16 , wherein said interconnection structures comprise a pattern of undulations both in an unexpanded and expanded configuration. 
   
   
       18 . The stent of  claim 16 , wherein said interconnection structures comprise a pattern containing no undulations in both an unexpanded and expanded configuration. 
   
   
       19 . The stent of  claim 16 , wherein said interconnection structures expand between undulations of said paired circumferential bands. 
   
   
       20 . The stent of  claim 16 , wherein at least one of said plurality of paired biodegradable circumferential bands includes along said outer tubular surface a radio-opaque material capable of being detectable by radiography, MRI or spiral CT technology. 
   
   
       21 . The stent of  claim 16 , wherein at least one of said interconnection structures includes along said outer tubular surface a radio-opaque material capable of being detectable by radiography, MRI or spiral CT. 
   
   
       22 . The stent of  claim 20 , wherein said radio-opaque material is housed in a recess on one of said circumferential bands. 
   
   
       23 . The stent of  claim 21 , wherein said radio-opaque material is housed in a recess on one of said interconnection structures. 
   
   
       24 . The stent of  claim 16 , wherein at least one of said interconnection structures and at least one of said circumferential bands includes a radio-opaque material along the outer tubular surface which is detectable by radiography, MRI or spiral CT technology. 
   
   
       25 . A biosorbable and flexible scaffold circumferential about a longitudinal axis and substantially forming a tube, said tube having a proximal open end and a distal open end, and being crimpable and expandable, and comprising in expanded form:
 a) at least two rings circumferential about said longitudinal axis, said rings having an inner surface proximal to said longitudinal axis, an outer surface distal to said longitudinal axis, a top surface proximal to said proximal open end and a bottom surface proximal to said distal open end, said ring inner and outer surfaces about their circumferences being orthogonal to said longitudinal axis and within substantially the same plane, and   b) a plurality of meandering strut patterns located between said at least two rings and circumferential coursing about said longitudinal axis; said plurality of meandering strut patterns connected to said rings at least two connection points on the circumference of each ring, and each connection point on the circumference of the ring on both said top ring surface and said bottom ring surface;   
     wherein each of said connection points with any particular ring is symmetrical in structure above and below the upper and lower surface of said ring. 
   
   
       26 . The scaffold of  claim 25 , wherein said connection points of said rings, the meandering strut pattern above said ring upper surface and below said ring lower surface in conjunction form a stylized H configuration. 
   
   
       27 . The scaffold of  claim 25 , wherein at said connection points of said rings, the meandering strut pattern above said ring upper surface and below said ring lower surface in conjunction form two abutting sinusoids. 
   
   
       28 . The scaffold of  claim 25 , wherein at said connection points of said rings, the meandering strut pattern above said ring upper surface and below said ring lower surface in conjunction form two sinusoids with intervening structure connecting the same and said ring. 
   
   
       29 . The scaffold of  claim 25 , wherein said connection points of said rings have between 2-6 meandering strut pattern connections at each connection point.