Thrombus removal system and process

Abstract

A device capable of capturing and facilitating the removal of a thrombus in blood vessels (or stones in biliary or urinary ducts, or foreign bodies) uses a soft coil mesh with the aid of a pull wire or string to engage the surface of a thrombus, and remove the captured thrombus. The soft coil mesh is formed by an elongated microcoil element that forms the helical elements of a macrocoil element. The microcoil element provides a relatively elastic effect to the helical elements forming the macrocoil and allows for control of gripping forces on the thrombus while reducing non-rigid contact of the device with arterial walls. The use of multiple coil mesh elements, delivered through a single lumen or multiple lumens, preferably with separate control of at least one end of each coil, provides a firm grasp on a distal side of a thrombus, assisting in non-disruptive or minimally disrupted removal of the thrombus upon withdrawal of the device.

Description

RELATED APPLICATION DATA[0001]The present application claims priority from U.S. Provisional Application Ser. No. 60 / 851,699 filed 13 Oct. 2006 and is a continuation-in-part of U.S. patent application Ser. No. 11 / 356,321 filed 16 Feb. 2006 now U.S. Pat. No. 7,955,345, which is in turn a continuation-in-part of U.S. patent application Ser. No. 11 / 097,354, filed 1 Apr. 2005 now U.S. Pat. No. 7,955,344.BACKGROUND OF THE INVENTION[0002]1. Field of the Invention[0003]The present invention pertains to intravascular medical devices. More particularly, the present invention pertains to devices for isolating, capturing, and removing blood clots from a blood vessel. This same system may also be used to safely and effectively retrieve obstructions, such as coils, balloons, or catheter fragments dislodged during interventional procedures, from the blood stream. The same system may further be used to remove obstructions from ducts and other cavities of the body, such as, for example, foreign bodi...

AI Technical Summary

Benefits of technology

The invention provides a mechanical device that can reliably and safely remove thrombus or other blockages in blood vessels using a soft coil mesh and pull wire. The device is positioned using MRI or angiography guided percutaneous transluminal catheter delivery within the lumen of the blood vessel. The soft coil mesh is formed by an elongated microcoil element that provides reliable dynamic compliance matching with the viscoelastic properties of the thrombus. The device can be safely and completely removed thrombus of any density from any blood vessel in the human body. Eyelets may also be provided to facilitate engagement of the thrombus with the macromoil.

Problems solved by technology

Such clots may occasionally be harmlessly dissolved in the blood stream.

At other times, however, such clots may lodge in a blood vessel or embolize to a distal blood vessel where they can partially or completely occlude the flow of blood.

If the partially or completely occluded vessel provides blood to sensitive tissue such as the brain or heart, for example, serious tissue damage may result.

These drugs, however, do not immediately dissolve the blood clot and generally are useful only when administered within a short time period after onset of stroke symptoms.

The above systems may have various practical and cost disadvantages.

Although several of the commercial systems are designed to penetrate clot, this may in fact be impossible if the clot is made up of firm fibrin.

The process of engagement and retraction of a thrombus may also fractionate the clot, producing distal embolization.

Currently available systems can also be difficult to guide or deploy at the site of the thrombus, or may be traumatic to the artery, and some systems are quite expensive.

In addition, all these systems are bulky and cannot be safely and effectively used in small caliber blood vessels.

Images