Thrombectomy method and apparatus

Abstract

A thrombectomy method and apparatus for dissolving a soft fibrinous obstruction, such as a recently formed thrombus, within a patient's vascular system, either in a vessel or in a prosthetic implant, employing a rotating brush for separating and mixing the fibrin of the thrombus while a dissolving agent, e.g. streptokinase or urokinase, is introduced and mixed in and applied to the separated fibrin. The brush is formed of soft, flexible bristles that extend outward from the distal end of an elongated, flexible, rotatable drive shaft having a drive motor assembly attached at its proximal end. In use, an introducer catheter is introduced through a patient's blood vessels until the distal end opening is positioned adjacent the thrombus. The brush is passed through the introducer lumen and out the distal opening to place the brush bristles in contact with the thrombus. The dissolving agent is introduced into the region of rotation of the brush either through the introducer catheter lumen or a drive shaft lumen for dissolving the soft thrombus as it is mixed by the bristles. The bristles are sufficiently resilient and dimensioned for ease of introduction and mixing into the fibrin of the soft thrombus, while not damaging the vessel wall. Optionally, a balloon catheter or a mesh basket may be coaxially introduced through the drive shaft lumen and placed downstream to restrain fragments and to allow the dissolving agent to complete the dissolution thereof.