Revision using distal inflow for high flow hemodialysis access alters arterial flow characteristics in the dialysis arm

Objective: Revision using distal inflow (RUDI) is currently proposed in patients on hemodialysis having a high flow access (HFA; >2 L/min) or hemodialysis access-induced distal ischemia (HAIDI). However, a recurrence of high flow or hand ischemia is not unusual in the years after RUDI. The aim of the present study was to describe changes in flow characteristics and arterial diameters in the dialysis arm after RUDI for HFA.Methods: Volume flow, diameter, peak systolic velocity and end diastolic velocity of the brachial artery (BA) were studied 2 and 12 months after RUDI using duplex imaging. In a portion of patients, these characteristics were also assessed at proximal and distal portions of radial and ulnar arteries (proximal forearm radial artery, distal radial artery, ulnar artery, and distal ulnar artery), and in the greater saphenous venous interponate. HFA patients were grouped according to presence of concomitant hand ischemia (HFA-HAIDI) or absence (HFA).Results: Fifteen patients (54 +/- 16 year old; 10 males; HFA-HAIDI, n = 6; HFA, n = 9) with a BA HFA (flow volume, 2740 6 322 mL/min) undergoing RUDI were studied between March 2011 and October 2016 in two Dutch hospitals. After 2 months, flow volume had decreased (1180 +/- 189 mL/min), but again increased at 12 months (1520 +/- 217 mL/min; P <.001). BA diameters did not change (7.4 +/- 0.5 mm), but proximal forearm radial diameters doubled (overall 2.6 +/- 0.2 mm to 5.4 +/- 1.0 mm; P <.001), albeit less prominent in HFA-HAIDI (+80%) than in HFA (+130%; P = .019). During follow-up, the distal ulnar artery peak systolic velocity in HFA-HAIDI (83 +/- 10 cm/s) was higher compared with the HFA group (54 +/- 5 cm/s; P <.01). Dilatation was not present in the greater saphenous venous interponate.Conclusions: RUDI for HFA reduction does not reverse BA dilatation, suggesting irreversible structural arterial wall damage possibly contributing to recurrent high flow. Radial artery remodeling is attenuated in HFA patients previously reporting concurrent hand ischemia diminishing the likelihood of high flow recurrence in this subgroup.