Fabrication of Small Caliber Stent-grafts Using Electrospinning and Balloon Expandable Bare Metal Stents.
Stent-grafts are widely used for the treatment of various conditions such as aortic lesions, aneurysms, emboli due to coronary intervention procedures and perforations in vasculature. Such stent-grafts are manufactured by covering a stent with a polymer membrane. An ideal stent-graft should have a biocompatible stent covered by a porous, thromboresistant, and biocompatible polymer membrane which mimics the extracellular matrix thereby promoting injury site healing. The goal of this protocol is to manufacture a small caliber stent-graft by encapsulating a balloon expandable stent within two layers of electrospun polyurethane nanofibers. Electrospinning of polyurethane has been shown to assist in healing by mimicking native extracellular matrix, thereby promoting endothelialization. Electrospinning polyurethane nanofibers on a slowly rotating mandrel enabled us to precisely control the thickness of the nanofibrous membrane, which is essential to achieve a small caliber balloon expandable stent-graft. Mechanical validation by crimping and expansion of the stent-graft has shown that the nanofibrous polyurethane membrane is sufficiently flexible to crimp and expand while staying patent without showing any signs of tearing or delamination. Furthermore, stent-grafts fabricated using the methods described here are capable of being implanted using a coronary intervention procedure using standard size guide catheters.
Division of Engineering, Mayo Clinic.
Susheil
S
Uthamaraj
Department of Cardiovascular Diseases, Mayo Clinic.
Brandon J
BJ
Tefft
Department of Cardiovascular Diseases, Mayo Clinic.
Soumen
S
Jana
Department of Cardioangiology, ICRC, St. Anne's University Hospital.
Ota
O
Hlinomaz
Department of Vascular Surgery, Mayo Clinic.
Manju
M
Kalra
Department of Cardiovascular Diseases, Mayo Clinic.
Amir
A
Lerman
Division of Engineering, Mayo Clinic; Department of Physiology and Biomedical Engineering, Mayo Clinic.
Dan
D
Dragomir-Daescu
Department of Cardiovascular Diseases, Mayo Clinic; sandhu.gurpreet@mayo.edu.
Gurpreet S
GS
Sandhu
D001011:Aorta; D004867:Equipment Design; D006801:Humans; D008670:Metals; D057139:Nanofibers; D011140:Polyurethanes; D011474:Prosthesis Design; D015607:Stents; D019737:Transplants
D008670:Metals; D011140:Polyurethanes