Stent graft with variable coverage of wavy rings

A stent graft, comprising:

• at least one region T disposed along an axial direction of the stent graft, the region T is partitioned by two planes p1 and p2;
• the region T comprises a plurality of wavy rings, each wavy ring is a closed cylindrical structure, and comprises a plurality of proximal vertices, a plurality of distal vertices, and supporting bodies connecting the adjacent proximal vertices and distal vertices;
• the region T with the plurality of wavy rings is divided into at least, in a circumferential direction, a region A partitioned by said two planes p1 and p2 and a region B partitioned by said two planes p1 and p2 connected with the region A from said plane p1 to said plane p2;
• and
• each of the region A and region B comprises the wavy rings in a corresponding region of the region T;
• wherein a ratio of an area of the region A to an area of the region T ranges from 1/4 to 2/3;
• a ratio of a coverage rate of the wavy rings in the region A to a coverage rate of the wavy rings in the region B ranges from 1/5 to 9/10;
• and a ratio of a coverage rate of the wavy rings in each circular region with a diameter of 20 mm within the region A to the coverage rate of the wavy rings in the region A ranges from 0.7 to 0.9, or from 1.1 to 1.3;
• wherein each circular region with a diameter of 20 mm within the region A is a two-dimensional circular region randomly defined in the region A, and the two-dimensional circular region has a diameter of 20 mm and comprises the wavy rings in a corresponding region of the region A;
• and wherein the area of region A is larger than an area of each circular region with a diameter of 20 mm within region A, and the coverage rate of the wavy rings in each region is calculated in a way that a surface area of the wavy rings projected onto an inner wall of a tube cavity of the stent graft in the each region is divided by a surface area of the corresponding inner wall of the tube cavity of the stent graft in the each region and multiplied by 100;
• wherein the plurality of wavy rings of the region T comprises a first wavy segment located in the region A, where the first wavy segment includes a plurality of first proximal vertices of the plurality of proximal vertices, a plurality of first distal vertices of the plurality of distal vertices, and first supporting bodies of the supporting bodies, the first supporting bodies connecting adjacent first proximal vertices and first distal vertices;
• and
• wherein the plurality of wavy rings of the region T further comprises a second wavy segment located in the region B, a wave included angle of the first wavy segment is greater than a wave included angle of the second wavy segment, and a wave height of the first wavy segment is the same as a wave height of the second wavy segment;
• wherein the stent graft further comprises one proximal wavy ring located at one end of the region T, and one distal wavy ring located at a second end of the region T, respectively;
• wherein a coverage rate of the wavy rings in a region where the at least one proximal wavy ring is located is greater than a coverage rate of the plurality of wavy rings in the region T, and a coverage rate of wavy rings in a region where the at least one distal wavy ring is located is greater than the coverage rate of the plurality of wavy rings in the region T;
• wherein the stent graft further comprises at least one non-end wavy ring located between the plane p2 and the distal wavy ring, and a coverage rate of wavy rings in a region where the at least one non-end wavy ring is located is greater than a coverage rate of the plurality of wavy rings in the region T, the proximal wavy ring, the non-end wavy ring, and the distal wavy ring are of closed cylindrical structures.