Screening for non-significant stenosis in native arteriovenous fistula within the Maltese population

Abstract

Purpose: To assess the feasibility of introducing a screening programme for patients with end stage renal disease undergoing haemodialysis through an autogenous arteriovenous fistula for the detection of asymptomatic stenosis of the feeding artery and/or fistula Objectives: To scan using duplex ultrasound the autogenous arteriovenous fistulae of the patients with end stage renal disease and identify any asymptomatic clinical stenosis; identify any co-morbid disease that can increase the risk of a stenosis. Create and test a suitable data collection tool. Methodology: Ninety nine patients that fulfilled the inclusion criteria were recruited for the study. Ten of these patients were enrolled for the pilot study and were not included in the main study. Eighty nine patients were asked a series of demographic questions and also underwent a duplex ultrasound examination where both the lumen diameter measurements and blood flow velocities were measured from the arterial and fistula segments. The results were then statistically analysed. Results: The introduction of a screening programme is recommended as the results show that 36% of the patients had undetected, asymptomatic stenoses within their fistula. Fifteen percent from these undetected stenoses were significant. The remaining were non-significant in nature. No stenosis was detected in the arterial segment. All the stenoses were within the anastamotic area or in the fistula itself. The results also showed that 25% of the scanned population had already suffered from either a stenotic or thrombotic event. The mean flow velocity was slightly higher than what is published in the literature. Diseases such as diabetes and hypertension accounted to 71% of the scanned population but these diseases did not show an increased risk for the patients to develop a stenosis. A costing exercise is recommended in order to assess that screening and treatment costs as well as the additional burden of hospital resources are justifiable. Conclusions: Thirty six percent of the patients currently undergoing haemodialysis with an autogenous arteriovenous fistula have an undetected stenoses. A screening programme would be beneficial for the patients undergoing haemodialysis using an autogenous arteriovenous fistula.