US 5,074,871 A · Catheter atherotome

Abstract

A catheter atherotome and method for its use for performing partial atherectomy in an artery and thereby enlarging the lumen effectively available for blood flow through the artery. An expansible cutter head at the distal end of a catheter includes several elongate flexible members mounted in a parallel array and spaced angularly apart from one another about the associated ends of two concentric members of the catheter in such a way that longitudinal and rotary relative movement of the members of the catheter selectively either bows the flexible members arcuately outwardly into a cutting position or draws them into alignment parallel with the catheter. A sharpened edge of a blade carried on at least one flexible member extends circumferentially and is directed toward the catheter's proximal end when the flexible members are bowed. Partial removal of an atheroma is effected by manually pulling the cutter head past an atheroma with the sharpened edge exposed, with the speed, force, and amount of expansion of the cutter head determined by the operator. Removal of cut-away pieces of atherosclerotic plaque material is accomplished either by pull-back of a balloon-tipped catheter or by use of a membrane enshrouding the cutter head to trap the shavings.

Claims19

Dependent claims

A catheter atherotome for use in surgical removal of plaque from the interior wall of an artery, comprising:

(a) an elongate tubular outer sheath having respective proximal and distal ends;
(b) an elongate inner member disposed within said outer sheath and having respective proximal and distal ends, said distal end of said inner member extending beyond said distal end of said outer sheath;
(c) a cutter head including a plurality of elongate flexible members each having a proximal end interconnected with said outer sheath and a distal end interconnected with said inner member;
(d) means for moving said inner member longitudinally with respect to said outer sheath so as to flex said elongate flexible members from a constricted configuration of said cutter head into an expanded configuration of said cutter head;
and
(e) at least one of said elongate flexible members being a blade carrier having a blade carried thereon, said blade defining a respective sharpened edge, at least a portion of said sharpened edge extending generally transversely with respect to the length of said blade carrier and facing generally toward said proximal ends of said outer sheath and said inner member.

3 more elements

A method of performing partial atherectomy of an artery to enlarge the effective lumen thereof, comprising:

(a) making an opening through a wall of an artery at a location spaced apart from an atheroma and more proximal to a patient's heart than said atheroma;
(b) inserting a catheter atherotome, having an expansible cutter head including a plurality of elongate flexible members, at least one of which is a blade carrier carrying a blade including a sharpened edge extending substantially transversely, into said artery through said opening;
(c) directing said catheter atherotome along the interior of said artery to the vicinity of said atheroma with said cutter head in a constricted configuration in which said sharpened edge is prevented by said blade carrier from cuttingly engaging the interior of said artery;
(d) directing and moving said catheter atherotome further along the interior of said artery until said cutter head passes beyond said atheroma;
(e) expanding said cutter head controllably and flexing said blade carrier, thereby exposing said sharpened edge to face in a proximal direction, so that said sharpened edge is located radially outward from a portion of said blade carrier which prevented said sharpened edge from cuttingly engaging the interior of said artery prior to the step of expanding said cutter head;
and
(f) thereafter manually retracting said catheter atherotome along said artery a distance great enough to being said sharpened edge into cutting engagement with said atheroma and disrupt the surface of said atheroma by longitudinal retrogression of said catheter atherotome and said blade of said cutter head.

4 more elements

Dependencies are inferred from the claim text.

Catheter atherotome

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Catheter atherotome

Life of this patent

Abstract

Claims19