PAD血管内治療の最新治療戦略 in Europe
市橋成夫
SFA領域の血管内治療ではstent内再狭窄が解決されるべき問題である。Self expanding stentの自己拡張による血管への長期にわたるストレス、周囲筋からのストレスによるstent fractureなどが原因となり、intimal hyperplasiaが生じて、再狭窄を来すとされる。近年はfracture抵抗性のstent、血管にストレスを与えず、血管の動きに従った可動性を持つvascular mimickingなstentが注目を浴びている。またstentなどの異物を留置せずに治療するdrug coated balloonも次世代治療の中心になると予想される。
Instent restenosis, deriving from intimal hyperplasia, has been an unsolved problem after endovascular treatment for the peripheral arterial disease(PAD). There are several causes of the intimal hyperplasia after stent placement：chronic outward force toward the arterial wall given by the nitinol self-expanding stent, mechanical force toward the stent given by the surrounding muscle. The persistent mechanical stress to the stent could result in the stent fracture, which could also be a cause of the instent restenosis. Therefore stents should be flexible, have vascular mimicking mobility and enough durability without excessive chronic outward force. Nothing left behind strategy using drug coated balloon(DCB)is also noteworthy in the point that unnecessary mechanical stress to the artery could be eliminated, with simplicity of retreatment after restenosis. In this article, we introduce the latest vascular stents and an overview of DCB.
