Effect of antithrombotic agents on the patency of PTFE-Covered stents in the inferior vena cava: An experimental study

  • Shiro Makutani
  • Kimihiko Kichikawa
  • Hideo Uchida
  • Munehiro Maeda
  • Noboru Konishi
  • Yoshio Hiasa
  • Tomohiro Yoshikawa
  • Yukio Kimura
Laboratory Investigations


Purpose: To evaluate the efficacy of antithrombotic agents in the prevention of stenosis of polytetrafluororethylene (PTFE)-covered stents in the venous system.

Methods: Spiral Z stents covered with PTFE (PTFE-covered stents) were placed in the inferior vena cava (IVC) of 34 dogs. Nineteen dogs, used as a control group, were sacrificed at 2, 4, and 12 weeks. Fifteen dogs, previously given antithrombotic agents [cilostazol (n=5), warfarin potassium (n=5), cilostazol plus warfarin potassium (n=5)] were sacrificed at 4 weeks, and then examined angiographically and histopathologically. The effect of the antithrombotic agents was compared between groups.

Results: The patency rate of the antithrombotic agent group was 93% (14/15), which was higher than the control group rate of 63% (12/19). The mean stenosis rate of the patent stent at both ends and at the midportion was lower at 4 weeks in the antithrombotic agent group than in the control group. In particular, the mean stenosis rate in the cilostazol plus warfarin potassium group was significantly lower than the control group (Tukey’s test, p < 0.05). The mean neointimal thickness of the patent stent at both ends and at the midportion was thinner at 4 weeks in the antithrombotic agent group than in the control group. In particular, the thickness of the neointima in the cilostazol plus warfarin potassium group was significantly decreased when compared with the control group (Tukey’s test p < 0.05). At 4 weeks, endothelialization in the antithrombotic agent group tended to be almost identical to that in the control group.

Conclusion: The present study suggests that administration of an antithrombotic agent is an effective way of preventing the stenosis induced by a neointimal thickening of PTFE-covered stents in the venous system.

Key words

Inferior vena cava Grafts and prostheses Thrombotic occlusion Antithrombotic drugs 


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Copyright information

© Springer-Verlag 1999

Authors and Affiliations

  • Shiro Makutani
    • 1
  • Kimihiko Kichikawa
    • 1
  • Hideo Uchida
    • 1
  • Munehiro Maeda
    • 2
  • Noboru Konishi
    • 3
  • Yoshio Hiasa
    • 3
  • Tomohiro Yoshikawa
    • 4
  • Yukio Kimura
    • 5
  1. 1.Department of RadiologyNara Medical UniversityNaraJapan
  2. 2.Department of RadiologyOsaka UniversityOsakaJapan
  3. 3.Second Department of PathologyNara Medical UniversityNaraJapan
  4. 4.Respiration & Circulation Research LaboratoryOtsuka Pharmaceutical Co., Ltd.TokushimaJapan
  5. 5.Thrombosis & Vascular Research LaboratoryOtsuka Pharmaceutical Co., Ltd.TokushimaJapan

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