Modified Intravascular Stent for Microvascular Suture in a Rat Superficial Femoral Artery.

Abstract

Intravascular stent (IVaS) is sometimes used for suturing small vessels, but removing the stent after suturing is difficult. To overcome this problem, we developed an IVaS that integrates a stent and a manipulating string. This study aimed to investigate the usefulness of the modified IVaS (M-IVaS) by comparing it with conventional sutures (CS) and conventional IVaS (C-IVaS). Forty-five superficial femoral arteries from rats were resected and sutured. The rats were randomly divided into the following 3 groups: CS, M-IVaS, and C-IVaS, with 15 rats per group. Patency rate, operating time, and ultrasonographic blood flow dynamics were examined immediately after suturing. Patency tests, ultrasonographic evaluations, and histological investigations were performed 1 week (n = 5), 2 weeks (n = 5), and 6 weeks (n = 5) after surgery. The 3 groups showed vessel patency in all cases immediately after suturing and at 1 week, 2 weeks, and 6 weeks after surgery. The mean operative time was 22.6 minutes for the CS group, 21.5 minutes for the M-IVaS group, and 25.9 minutes for the C-IVaS group. There were no significant differences in peak flow velocity and stenosis rate among the 3 groups as evaluated by ultrasonography. Histopathological evaluation revealed a similar recovery process of endothelial cells and no damage to the vascular wall. The surgical time using M-IVaS was significantly shorter compared to that using C-IVaS. The M-IVaS reduced the inconvenience of C-IVaS removal. M-IVaS showed the same effectiveness as did the CS in terms of patency rate, operating time, ultrasonographic blood flow dynamics, and histological evaluation. M-IVaS can be used in the field of microsurgery.