Purpose: To evaluate distal embolization while using the Hydrolyser (hydrodynamic thrombectomy catheter) with special attention to the severity of the stenosis and temporary distal or proximal flow obstruction.
Materials and methods: The Hydrolyser procedure was assessed in plastic tubes (5-8 mm) with a 70% or 90% diameter stenosis with or without temporary distal flow obstruction and a 72-hour-old clot proximal to the stenosis. The weight of the embolized particles was established after passage through filters of 1,000, 500, 100, and 10 microm. To evaluate the influence of the absolute inner diameter of the stenosis 1.0-, 2.1-, and 3.0-mm stenoses were compared in 10-mm tubes.
Results: Thrombus removal was greater than 99.9% in all but one of the cases in the 5-8-mm tubes. Embolization with a weight of more than 1 mg was only found in tubes with a relative stenosis of 70% and a stenosis inner diameter of greater than 1.5 mm. There was a positive relationship between inner diameter of the stenosis and the amount of distal embolization. In the presence of a proximal or distal temporary flow obstruction during thrombectomy, no distal embolization greater than 1 mg was found.
Conclusion: In this in vitro study, the Hydrolyser thrombectomy device demonstrated minimal distal embolization. The amount of distal embolization that did occur was related to the absolute stenosis diameter and could be prevented by a severe distal stenosis and/or a temporary proximal or distal flow obstruction.