Vascular Access News

New approaches to long-term vascular access problems are arriving. One group is working in trials to get approval for its system for creating vascular access. The other team is working to prevent needle sticks that penetrate into and through the vascular graft walls, causing profuse bleeding.

TVA Medical( Austin, TX), is developing minimally invasive therapies for patients with ESRD. TVA has completed $15 million in financing with new investors Baxter Ventures (lead) and Boston Scientific, as well as existing strategic investors. TVA hopes to accelerate its market development for the everlinQ endoAVF system, a catheter-based technology that is designed to create hemodialysis access for patients with chronic kidney disease using a minimally invasive procedure.

The system creates an arteriovenous fistula for hemodialysis. During the access procedure, two thin, flexible magnetic catheters are inserted into an artery and a vein in the arm. A small burst of radiofrequency energy into the catheter area connects the artery and vein to create the fistula, and the catheters are removed. The system has been studied outside the US and has received a CE mark in Europe. It is not currently available, however, in the US and has not yet been approved for commercial use by the Food and Drug Administration.

Funding will support the ongoing Novel Endovascular Access Trial (NEAT) clinical study; completion of the 12-month follow-up is expected in 2016.

Needle pokes constitute another problem. Because patients receiving dialysis often have painful bruising and infections from needles that overreach (entering one side of the vascular access and exiting from the other), a system that prevents bleeding from such needle insertions would be welcome.

Duke University physicians who have studied the problem have created a new device, called Bullet Proof. Their new vascular graft is identical with those conventionally used but also contains two penetration-resistant chambers. One is for the needle that sends blood out of the body; the other is for the needle that sends the blood back in. Each chamber is built with a “window of material that seals itself after each needle poke,” according to an article published by the Duke Translational Medicine Institute. Along the back of the tube is a rigid plate that makes it impossible for a needle to go straight through the graft. When a needle is pushed too far, it bends rather than penetrating the wall. The doctors are working to finalize their device design and to test the ability of the device to resist punctures and self-seal wounds. Currently the investigators are conducting a large-animal study and implanting grafts to learn how well they will work in vivo.

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The Duke team has already fabricated simple prototypes of their new device and has launched a company called InnAVasc (http://innavasc.com) with a goal of marketing the graft.