UL researchers develop new dialysis product

An invention by researchers based at the Materials & Surface Science Institute (MSSI) at the University of Limerick (UL) which could radically reduce the number of surgeries among dialysis patients had been granted a European patent. The Prolong AV Graft offers improved vasculature access to doctors treating patients suffering from of End Stage Renal Disease (ESRD).

The Prolong AV Graft aims to ensure that the chances of AV graft failure within the first two years is significantly reduced. UL researchers Dr Michael Walsh, Professor Tim McGloughlin are co-inventors of the Prolong AV graft along with Prof Pierce Grace, consultant vascular surgeon at the Mid-Western Regional Hospital and Adjunct Professor of Surgical Science at UL.

Dr Michael Walsh, who is leading the project at UL, said; 'there is significant potential benefit to patients if the functioning life of grafts used for dialysis access could be prolonged, reducing the number of revision surgeries. The Prolong AV graft aims to eliminate the formation of disease at the graft-venous junction.'

The patent-protected geometry of the Prolong AV graft prevents disease formation at the graft-vein junction through improved hemodynamics resulting in increased graft patency, reduced treatment cost and a better patient experience.

Prof Tim McGloughlin, said; 'I am confident that the non-intuitive design features of the Prolong AV graft would lead to substantially superior performance to the grafts currently used. The Prolong graft can be made from both synthetic and non-synthetic material ensuring the device will appeal to both the emerging growth market sector for non-synthetic grafts and the established synthetic AV graft market which is worth $300 million worldwide per year.'

Paul Dillon, Director of the Technology Transfer Office at the University of Limerick, paid tribute to the achievements of the research team for 'producing a research outcome now recognised in US and European Law as being useful, novel and inventive'. While acknowledging a positive outcome of the two pre-clinical trials currently underway in the US under the supervision of Key Opinion Leaders is the next critical milestone, Dillon went on to say 'the University is actively examining the potential to form a spin-out company to bring this product through early-stage clinical studies and is keen to speak to entrepreneurs with appropriate medical device sector experience.'

The research that resulted in the creation of the Prolong AV Graft was funded by Enterprise Ireland, with the State agency also providing support to the University’s Technology Transfer Office (TTO) to assist in the commercialisation of the research.

Professor Brian Fitzgerald, Vice President Research at the University of Limerick welcomed the announcement; 'the Prolong AV Graft developed by UL researchers has now received both US and European patents. This is a significant milestone achievement and testament to the groundbreaking design of this product. It is an excellent validation of our translation research approach.'

Dialysis access is necessary in patients with End Stage Renal Disease. These patients require dialysis, a process by which the blood is cleaned in a machine external to the body.

The process requires access to the circulating blood and this is usually done in the forearm where blood is taken from the arm, passed through the dialysis machine and returned to the circulation again through the arm.

Taking the blood from the arm requires a surgical procedure where a short circuit is created between the arterial blood vessels and the venous blood vessels. This short circuit has several forms and this invention addresses the problems encountered when creating this short circuit using a graft. Such grafts have a functioning life of less than 2 years in half the cases that they are used. Most of the problems occur where the flow from the artery enters the vein, with disease forming in the junction area leading to blocking of the graft.

The Prolong AV graft is currently undergoing pre-clinical trials in the United States. The non-intuitive design features of the Prolong AV graft include splitting of the flow within the graft and rejoining the flow at the venous junction in an opposing fashion. This ensures that the flow entering the vein hits off itself creating self-correcting flow patterns. The flow moves through the vein with significantly reduced wall shear stresses, the friction forces implicated in the disease formation process.

Prof Pierce Grace said; 'Once the concept of the novel device is proven in the dialysis access application the device will have further applications in peripheral bypass surgery, a procedure where blood flow is restored to a limb with a blocked artery which, if left untreated, would lead to limb amputation.'

Click here for more information about the University of Limerick.