Electrosurgical catheter for resolving atherosclerotic plaque by radio frequency sparking

Claim 1

An electrosurgical device for resolving an occlusive deposit in a lumen of a subject, said device having a distal end which is insertable within and along the lumen and manipulatable therethrough to a desired position where the device is operated to resolve the occlusive deposit by radio frequency sparking, said device comprising: (a) an elongated flexible hollow tube having a distal end, a proximal end, and a diameter smaller than the diameter of the lumen into which said device is being inserted; (b) a plurality of electrodes proximate or on said distal end of the tube, the electrodes being radially spaced about the tube; (c) selection means in electrical communication with the electrodes for selectively supplying a radio frequency electrical current to at least one of said electrodes whereby said at least one electrode becomes a transmitting electrode and a user can select the radial location of the occlusive deposit corresponding to the transmitted electrode so as to minimize damage to the lumen and maximize occlusive deposit removal; and wherein said radio frequency sparking occurs between said electrodes and said occlusive deposit and the current returns to said selection means via a patient plate adapted to be attached to a portion of the subject remote from the location of the occlusive deposit.

Claim 22

A method of reducing the flow restriction effects of an occlusive deposit located at a point in a vessel of a subject, comprising: (a) obtaining access to the interior of said vessel; (b) inserting the distal end of a catheter consisting of an electrical conductor terminated in a plurality of radially spaced electrodes into said vessel; (c) adjusting the position of said electrodes adjacent to said point; (d) identifying the radially spaced electrodes adjacent to the occlusive deposit; and (e) selectively applying radio frequency energy to the identified electrodes adjacent to said occlusive deposit so that said energy will cause ablation from only the identified electrodes to resolve the occlusive deposit while minimizing damage to the vessel wherein said ablation occurs between said electrodes and said occlusive deposit and the current exits the subject via a patient plate attached to a portion of the subject remote from the location of the occlusive deposit.

Claim 23

A method of reducing the flow restriction effects of an occlusive deposit located at a point in a vessel of a subject, comprising: (a) obtaining access to the interior of said vessel; (b) inserting the distal end of a catheter consisting of an electrical conductor terminated in a plurality of radially spaced electrodes into said vessel; (c) adjusting the position of said electrodes adjacent to said point; (d) identifying the radially spaced electrodes adjacent to the occlusive deposit; and (e) selectively applying radio frequency energy to the identified electrodes adjacent to said occlusive deposit so that said energy will cause ablation from only the identified electrodes to resolve the occlusive deposit while minimizing damage to the vessel wherein said ablation occurs between said electrodes and said occlusive deposit and the current exits the subject via a patient plate attached to a portion of the subject remote from the location of the occlusive deposit.