The presence of thrombus in a coronary vessel during percutaneous revascularisation can prevent adequate restoration of flow; it is also associated with an increased risk of distal embolization. We report the acute results and longer-term outcome of seven patients who underwent treatment with a new hydrodynamic thrombectomy catheter (Hydrolyser), designed for the rapid removal of acute, non-organised thrombus from coronary vessels. Three patients demonstrated total thrombotic occlusion of a coronary saphenous vein bypass graft (SVBG), whereas in four patients thrombus was present in a native coronary artery (NCA). In all seven patients, Hydrolyser thrombectomy resulted in removal of thrombus and restoration of flow through the occluded segment. Adjunctive balloon angioplasty or stent placement to treat residual stenosis was performed in five of the patients. Distal embolization of a free-floating thrombus mass occurred in one patient, without clinical sequelae. There were no procedure-related complications in any of the patients. One patient with a degenerated SVBG reoccluded after five days. The other six patients underwent angiographic follow-up after an interval of 3 to 8 months: A wide patent coronary artery, without restenosis, was seen in three of these patients, and the other three patients (two with treatment of an SVBG) underwent re-PTCA for restenosis. These data suggest that the Hydrolyser procedure, as reported in our experience, is safe and effective for the removal of acute thrombus in selected patients.