Our purpose was to describe initial experience with a new mechanical thrombectomy catheter for treating haemodialysis fistulae. The Hydrolyser thrombectomy catheter combines thrombus fragmentation by a saline jet with simultaneous low-pressure aspiration. This catheter was used in six cases of dialysis-fistula occlusion. In four instances this was a polytetrafluoroethylene loop, in two cases a Brescia-Cimino fistula. In all cases rapid revascularization was obtained without complications. Reocclusion occurred in one patient, immediate reintervention being successful. Our initial results suggest that the Hydrolyser is a quick, minimally invasive, and useful alternative to the presently accepted methods of revascularizing occluded haemodialysis fistulae.