Angioplastic method for removing plaque from a vas

Claim 1

A transluminal balloon angioplastic method for removing at least a portion of fatty artherosclerotic plaque initially in non-removable form that partially occludes the lumen of a vas, thereby to increase the size of the lumen; said method comprising the steps of: (a) inserting into said vas a catheter arrangement having: (1) a deflated balloon disposed off-center of the longitudinal axis of said catheter arrangement in a first sidewall of said catheter arrangement, said deflated balloon being located at a given longitudinal position situated toward the distal end of said catheter arrangement; (2) an aperture disposed off-center of the longitudinal axis of said catheter arrangement in a second sidewall of said catheter arrangement that is located substantially opposite to said first sidewall, said aperture being located substantially at said given longitudinal position; and (3) means for preventing gas from entering said vas through said aperture while said balloon is deflated; (b) positioning said catheter arrangement so that said aperture is in proximity to the fatty artherosclerotic plaque which includes said portion to be removed; (c) inflating said balloon so that said balloon presses against a part of a wall of said vas located substantially opposite to the fatty artherosclerotic plaque which includes said portion to be removed, thereby causing said aperture to be pressed against the fatty artherosclerotic plaque that includes said portion to be removed with a first pressure that provides sufficient firmness to prevent any fluid in said vas from entering the interior of said catheter arrangement through said aperture while said balloon is inflated; (d) while said balloon is inflated, applying heat energy for a limited time to the fatty artherosclerotic plaque which includes said portion to be removed, which applied heat energy raises the temperature of the fatty artherosclerotic plaque under said first pressure to a value which is sufficient to cause at least a portion thereof to liquify and rise to the surface of the plaque then in contact with said aperture, but which temperature is insufficient to cause death of underlying tissue of said vas; and (e) while said balloon is inflated, applying sufficient suction to the interior of said catheter arrangement to reduce the relative pressure within the interior of said catheter arrangement in the vicinity of said aperture to a second pressure to cause said liquified plaque portion being sucked into the interior of said catheter arrangement through said aperture and then being sucked out of said catheter arrangement at the proximal end thereof.