title: The primary patency and fracture rates of self-expandable nitinol stents placed in the popliteal arteries, especially in the P2 and P3 segments, in Korean patients.
abstract: OBJECTIVE
  We wanted to evaluate the status of self-expandable nitinol stents implanted in the P2 and P3 segments of the popliteal artery in Korean patients.
  
  
  METHODS
  We retrospectively analyzed 189 consecutive patients who underwent endovascular treatment for stenoocclusive lesions in the femoropopliteal artery from July 2003 to March 2009, and 18 patients who underwent stent placement in popliteal arterial P2 and P3 segments were finally enrolled. Lesion patency was evaluated by ultrasound or CT angiography, and stent fracture was assessed by plain X-rays at 1, 3, 6 and 12 months and annually thereafter.
  
  
  RESULTS
  At the 1-month follow-up, stent fracture (Type 2) was seen in one limb (up to P3, 1 of 18, 6%) and it was identified in seven limbs at the 3-month follow-up (Type 2, Type 3, Type 4) (n = 1: up to P2; n = 6: P3). At the 6-month follow-up, one more fracture (Type 1) (up to P3) was noted. At the 1-year follow-up, there were no additional stent fractures. Just four limbs (up to P2) at the 2-year follow-up did not have stent fracture. The primary patency was 94%, 61% and 44% at 1, 3 and 6 months, respectively, and the group with stent implantation up to P3 had a higher fracture rate than that of the group that underwent stenting up to P2 (p < 0.05).
  
  
  CONCLUSIONS
  We suggest that stent placement up to the popliteal arterial P3 segment and over P2 in an Asian population can worsen the stent patency owing to stent fracture. It may be necessary to develop a stent design and structure for the Asian population that can resist the bending force in the knee joint.
authors: Department of Radiology, Konkuk University Hospital, Seoul 143-729, Korea.
authors: Il Soo
authors: IS
authors: Chang
authors: Hyun Keun
authors: HK
authors: Chee
authors: Sang Woo
authors: SW
authors: Park
authors: Ik Jin
authors: IJ
authors: Yun
authors: Jae Joon
authors: JJ
authors: Hwang
authors: Song Am
authors: SA
authors: Lee
authors: Jun Seok
authors: JS
authors: Kim
authors: Seong-Hwan
authors: SH
authors: Chang
authors: Hong Geun
authors: HG
authors: Jung
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000497:Alloys; D000792:Angiography; D001157:Arterial Occlusive Diseases / Q000000981:diagnostic imaging / Q000628:therapy*; D016009:Chi-Square Distribution; D005260:Female; D005471:Fluoroscopy; D006801:Humans; D007723:Korea; D007866:Leg / Q000098:blood supply; D008297:Male; D008875:Middle Aged; D016491:Peripheral Vascular Diseases / Q000000981:diagnostic imaging / Q000628:therapy*; D011150:Popliteal Artery; D011475:Prosthesis Failure; D012189:Retrospective Studies; D015607:Stents; D014057:Tomography, X-Ray Computed; D018615:Ultrasonography, Doppler, Color; D018616:Ultrasonography, Doppler, Duplex; D014654:Vascular Patency
chemical_list: D000497:Alloys; C013616:nitinol