UK team uses NHS funding to develop innovative catheter system

The project has received £1m funding from the National Health Service (NHS) to further develop the first minimally invasive procedure that uses a stent graft to form a fistula for dialysis.

More than 2.5 million people worldwide have kidney conditions that require their blood to be routinely filtered by a dialysis machine and many patients undergo a surgical procedure to prepare their veins for the filtration process. This involves a surgeon creating a connection in the arm - a fistula - between an artery and a vein, which is then connected to a dialysis machine.

Although they are the gold standard in medical care, fistulas are unreliable, often blocking up and requiring repeated costly repair operations. In the US alone, $4.6bn is spent annually to treat failing fistulas.

The market in the US, France, Germany and the UK for vascular access technologies is conservatively estimated at around $550m and $1.1bn worldwide

Now, the team at Imperial have developed prototype technology for inserting the stent graft between a patient’s artery and vein with greater precision and accuracy.

The device - Electronic Percutaneous Anastomosis Technology for Haemodialysis (ePATH) - will help some patients with kidney failure to avoid open surgery before beginning dialysis treatment. According to Imperial, this is because the ePATH catheter system creates a vascular access site in a minimally invasive manner, with less trauma for patients. In turn, this is expected to lead to faster recovery times, and enable patients to use dialysis machines sooner.

The ePATH system lets surgeons insert catheters into the vein and artery through needle-sized punctures in the skin, instead of opening up the arm. The surgeon then guides two catheters through to the artery and vein to the appropriate site in the arm, where an electronic alignment system is activated, manoeuvring the catheters so that they are properly aligned. A small needle would then cross from one catheter to other, creating a channel between the two. A guide wire would then be passed through the needle and another catheter inserted. This final catheter deploys the stent graft, which remains inside the patient’s arm to form the connection between the vein and artery.

Sorin Popa carried out the underpinning research for this technology at Imperial in 2014. Popa is now a visiting researcher at Imperial and together with Dr Robert Dickinson from the Department of Bioengineering, they formed spinout company Stent Tek to further develop and commercialise the technology.

The next steps of the research will now be carried out by Popa and Dr Dickinson at the College in conjunction with Imperial College Healthcare NHS Trust.

The team plans to move to the next phase and start in-vivo trials in 2016. In early 2018, they aim to carry out clinical trials with patients. Following this stage the team expect to get the technology approved for market release in Europe and the US and into the European market by late 2018.