Impact of Isometric Exercise in Adolescents With End Stage Kidney Disease and Unsuitable Vessels For An Autologous Arteriovenous Fistula.

Introduction: Despite the lack of calcification, to perform a native Arteriovenous Fistula (AVF) in young patients may pose a challenge due to small vessel diameter. We report a case series with no options of AVF in which vessel caliber improvement after isometric exercise allowed for radiocephalic fistula creation in all of them. Methods: Since 2017 to 2019, four patients were referred to our unit to create an AVF. Following a first assessment with physical examination and doppler ultrasound, none of them were eligible for AVF performance due to small vessel caliber. Once they were considered unsuitable for it, they started an isometric exercise program. Results: Age ranged from 13 to 19 years. There were three males and one female. Two were in predialysis and two in hemodialysis program. Initial diameters of the forearm cephalic vein and the radial artery respectively were: case A < 1.5/2.3 mm, case B 1.5/1.6 mm, case C < 1.5/1.6 mm and case D 2.1/1.3 mm. Median duration of exercise program was 13 weeks (range 5-23). Post-exercise vessel diameters were: case A 2.7/2.3 mm, case B 2.5/2 mm, case C 2.8/1.8 mm and case D 2.7/2 mm. Radiocephalic AVF were performed in the four cases. After a median follow up of 19 months (range 9-30 months), 75% of patients required further interventions but all of them had a functional AVF. Conclusions: In these four cases isometric preoperative exercise allowed the creation of AVF. Without the improvement in vessel diameter observed afterwards, all of them would have been rejected for AVF performance. Despite the high rate of adjunctive interventions needed, given the safety of the program and the potential risks of Central Venous Catheters, we consider it a valuable option. [ABSTRACT FROM AUTHOR]