Remote AV-Fistula Monitoring in Predialysis Patients

Chronic kidney disease affects 850 million people worldwide. Many of these patients will need renal replacement therapy (RRT), which is mostly delivered by hemodialysis (HD). HD often involves surgical construction of an arteriovenous fistula (AVF) to provide the required access to the patient’s vascular system.

The Inspiration Behind the Innovation

Although it's a common treatment, 30–50 percent of all AVFs become permanently damaged because of unnoticed dysfunctions, requiring repeat surgery to construct a new AVF. Currently, patients have the responsibility for self-monitoring their AVF function and alerting their treatment team of possible dysfunctions. This is a serious burden that causes anxiety because the home-monitoring process is difficult to learn – and thus, comes with a high risk of AVF failures going unnoticed. Prompt identification of failures can significantly reduce the need for repeat AVF surgeries.

The Innovation 

The team has developed a wearable device that automatically monitors AVF function. The patch-based device records sounds produced by blood flow in the AVF and sends them to a gateway hub that communicates with a central cloud computer where the data are analysed and stored. An algorithm distinguishes between the sounds from functioning and non-functioning AVFs – and the system automatically alerts clinicians to call the patient in for further assessment in the case of dysfunction.

When an AVF dysfunction occurs, there's a 24-hour window in which repair is feasible via a relatively simple procedure. Early detection and repair are crucial because there are limited potential sites for AVF surgery, and the treatment options are limited once these are exhausted. Therefore, early and automatic detection of AVF failure can significantly improve patients’ quality of life by removing the responsibility and anxiety that comes with self-monitoring – and providing better treatment options.

The Team

Charlotte Strandhave: Senior Registrar, MD, PhD, Associate Professor; Department of Nephrology, Aalborg University Hospital

Oliver Korup Damsgaard: Research Assistant, M.Sc; Department of Nephrology, Aalborg University Hospital