Mechanical determinants of graft kinking.

Vascular grafts can be twisted inadvertently during implantation. If twisted excessively, they may kink and obstruct flow. In this study, in vitro experiments were performed to identify the mechanical factors that determine graft kinking.

Chronic loading and extension increases the acute breaking strength of polypropylene sutures.

Polypropylene sutures provide satisfactory strength for construction of vascular anastomoses, but occasionally they break. Experimental studies show that they break at reduced forces when they are subjected to chronic loads. Moreover, in patients, sutures are subject to acute loads superimposed on chronic loads.

Mechanics of end-to-end artery-to-PTFE graft anastomoses.

On some occasions vascular surgeons are called upon to construct an end-to-end anastomosis using prosthetic graft material. If a spatulated anastomosis is not fashioned, three important variables that are under the surgeon's control could affect anastomotic dimensions: (1) selection of graft material, (2) graft size relative to the native vessel, and (3) suture technique. Accordingly, studies were performed on 36 nonspatulated, end-to-end artery-to-polytetrafluoroethylene (PTFE) grafts to evaluate the effects of graft size and suture technique on anastomotic dimensions.

Mechanics of spatulated end-to-end artery-to-vein anastomoses.

It previously has been shown that in straight end-to-end artery-to-vein anastomoses, maximum dimensions are obtained with an interrupted suture line. Nearly equivalent dimensions are obtained with a continuous compliant polybutester suture (Novafil), and the smallest dimensions are obtained with a continuous noncompliant polypropylene suture (Surgilene). The present study was undertaken to examine these suture techniques in a spatulated or beveled anastomosis in living dogs.

Effect of pulsatile pressure on the breaking strength and movement of Prolene sutures.

Purpose: Most studies of sutures used in vascular surgery have used steadily applied loads. But in vivo, sutures are subject to pulsatile pressures. Pulsatile pressures could weaken sutures, or they could be beneficial by helping to slide the suture, thereby equilibrating the tension between unevenly tightened loops.