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

Background: 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).

Methods: 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.

Results: 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.

Conclusion: 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.