The study of rapamycin nanofibrous membrane for preventing arteriovenous fistula stenosis

A local vascular-encapsulated sustained-release drug delivery system containing degradable rapamycin nanofiber membrane patch was developed. Sustained drug release can meet the clinical requirement of exposing the venous anastomotic site to a dose of rapamycin can avoid side effects caused by systemic medication. • Sustained drug release maintains a consistent concentration of medication in the arteriovenous fistula. • The degradability of nanofiber membranes helps to avoid repeated surgical interventions and associated damage. • This approach avoids the systemic damage caused by widespread drug release. The maturity and patency of arteriovenous fistula (AVF) are essential for patients undergoing hemodialysis. Dysfunction of AVF due to neointimal hyperplasia (NIH) presents a significant clinical challenge. While balloon dilation therapy and open surgery can address this issue, they are associated with a higher likelihood of restenosis and reduced long-term durability. Therefore, there is an urgent need to establish a new method for inhibiting NIH to prolong the patency of AVF treatment. In this study, we developed a local vascular-encapsulated sustained-release drug delivery system containing degradable rapamycin nanofiber membrane patches (R-NFMs). During surgery, R-NFMs were wrapped around the anastomotic site of the AVF and the venous outflow tract. In vitro assessments demonstrated the consistent and stable release of rapamycin from the R-NFMs, confirming the material’s non-toxicity and its support of healthy cellular morphology. Animal studies further revealed that the experimental group showed significant reductions in neointimal and medial hyperplasia, as well as decreased expression of α-SMA, compared to controls. In conclusion, these findings suggest that R-NFMs are effective in inhibiting NIH and may serve as an innovative preventative approach to this pervasive issue.