Piston extension balloon dilatation catheter apparatus and method

Claim 2

Apparatus for dilating a partially occluded section of a blood vessel, said apparatus comprising: an elongated flexible catheter adapted for passage through the vessel, said catheter having an open distal end; an elastomeric balloon having a mouth sealingly secured in fluid communication with the open distal end of the catheter; a piston connected to the balloon and slidably received within the catheter for movement relative thereto between an extended condition wherein the piston stretches the balloon lengthwise and a retracted position wherein the piston releases the balloon from such stretching; means to selectively move the piston between the retracted and extended conditions; said balloon having an outer diameter in its uninflated and extended condition which is less than the outer diameter of said catheter; and means to impart internal fluid pressure to the catheter to selectively inflate the balloon.

Claim 3

Apparatus according to claim 1 further comprising stop means to prevent separation of the piston from the catheter and limit extension of the piston relative to the open distal end of the catheter.

Claim 4

Apparatus according to claim 1 wherein the means to selectively move the piston comprises a stylet extending through the catheter for abutting engagement with the piston.

Claim 5

Apparatus for dilating a partially occluded section of a vessel, said apparatus comprising: an elongated flexible catheter adapted for passage through the vessel, said catheter having an open distal end; an inflatable balloon having a mouth sealingly secured in fluid communication with the open distal end of the catheter; a piston connected to the balloon and slidably associated with the catheter for movement relative thereto between a condition extending the balloon lengthwise of the catheter and a condition relaxing the balloon from such extension; said balloon having an outer diameter in its uninflated and extended condition which is less than the outer diameter of said catheter; and stop means to prevent separation of the piston from the catheter and limit movement of the piston in the direction extending the balloon lengthwise of the catheter.

Claim 6

Apparatus for dilating a partially occluded section of a vessel, said apparatus comprising: an elongated flexible catheter adapted for passage through the vessel, said catheter having an open distal end; an inflatable balloon having a mouth sealingly secured in fluid communication with the open distal end of the catheter; a piston connected to the balloon and slidably associated with the catheter for movement relative thereto between a condition extending the balloon lengthwise of the catheter and a condition relaxing the balloon from such extension; said balloon having an outer diameter in its uninflated and extended condition which is less than the outer diameter of said catheter; and stop means to prevent separation of the piston from the catheter and limit movement of the piston in the direction extending the balloon lengthwise of the catheter.

Claim 7

Apparatus according to claim 4 further comprising a stylet extending through the catheter for abutting engagement with the piston to selectively move the piston between the conditions extending and relaxing the balloon.

Claim 8

Apparatus for dilating a partially occluded section of a blood vessel, said apparatus comprising: an elongated flexible catheter adapted for passage through the vessel, said catheter having an open distal end; an elastomeric balloon having a mouth sealingly secured in fluid communication with the open distal end of the catheter; a piston connected to the balloon and slidably received within the catheter for movement relative thereto between an extended condition wherein the piston stretches the balloon lengthwise and a retracted position wherein the piston releases the balloon from such stretching; means to selectively move the piston between the retracted and extended conditions; and means to impart internal fluid pressure to the catheter to selectively inflate the balloon, said means to selectively move the piston comprising a stylet extending through the catheter for abutting engagement with the piston, said piston comprising a flexible tubular body having a passage extending therein for slidable receipt of the stylet and a stop at the distal end of the passage for abutting engagement with the stylet.

Claim 9

Apparatus for dilating a partially occluded section of a blood vessel, said apparatus comprising: an elongated flexible catheter adapted for passage through the vessel, said catheter having an open distal end; an elastomeric balloon having a mouth sealingly secured in fluid communication with the open distal end of the catheter; a piston connected to the balloon and slidably received within the catheter for movement relative thereto between an extended condition wherein the piston stretches the balloon lengthwise and a retracted position wherein the piston releases the balloon from such stretching; means to selectively move the piston between the retracted and extended conditions; and means to impart internal fluid pressure to the catheter to selectively inflate the balloon, said means to selectively move the piston comprising a stylet extending through the catheter for abutting engagement with the piston, said piston comprising a flexible tubular body having a passage extending therein for slidable receipt of the stylet and a stop at the distal end of the passage for abutting engagement with the stylet.

Claim 10

Apparatus according to claim 6 wherein the body comprises a flexible coil spring having convolutions defining the passage.

Claim 11

Apparatus according to claim 6 wherein the body is fabricated of a flexible polymer material.

Claim 12

Apparatus for dilating a partially occluded section of a vessel, said apparatus comprising: an elongated flexible catheter adapted for passage through the vessel, said catheter having an open distal end; an inflatable balloon having a mouth sealingly secured in fluid communication with the open distal end of the catheter; a piston connected to the balloon and slidably associated with the catheter for movement relative thereto between a condition extending the balloon lengthwise of the catheter and a condition relaxing the balloon from such extension; stop means to prevent separation of the piston from the catheter and limit movement of the piston in the direction extending the balloon lengthwise of the catheter; and a stylet extending through the catheter for abutting engagement with the piston to selectively move the piston between the conditions extending and relaxing the balloon; said piston comprising a flexible tubular body having a passage therein for slidable receipt of the stylet and a stop at the distal end of the passage for abutting engagement with the stylet.

Claim 13

Apparatus for dilating a partially occluded section of a vessel, said apparatus comprising: an elongated flexible catheter adapted for passage through the vessel, said catheter having an open distal end; an inflatable balloon having a mouth sealingly secured in fluid communication with the open distal end of the catheter; a piston connected to the balloon and slidably associated with the catheter for movement relative thereto between a condition extending the balloon lengthwise of the catheter and a condition relaxing the balloon from such extension; stop means to prevent separation of the piston from the catheter and limit movement of the piston in the direction extending the balloon lengthwise of the catheter; and a stylet extending through the catheter for abutting engagement with the piston to selectively move the piston between the conditions extending and relaxing the balloon; said piston comprising a flexible tubular body having a passage therein for slidable receipt of the stylet and a stop at the distal end of the passage for abutting engagement with the stylet.

Claim 14

Apparatus according to claim 9 wherein the body comprises a flexible coil spring having convolutions defining the passage.

Claim 15

Apparatus according to claim 9 wherein the body is fabricated of a flexible polymer material.

Claim 18

A method according to claim 12 further comprising passing the balloon into the occluded section of the vessel while maintaining the balloon in the lengthwise extended condition.

Claim 19

A method according to claim 13 further comprising: relaxing the extension of the piston after placement of the balloon within the occluded section of the vessel to permit the balloon to contract lengthwise; and, inflating the balloon to laterally compress the occluded section.

Claim 20

A method according to claim 14 further comprising: securing the piston between the catheter and balloon to limit lengthwise extension of the balloon relative to the catheter and prevent separation of the balloon from the catheter.

Claim 21

A method according to claim 13 further comprising inflating the balloon within the occluded section of the vessel while maintaining the balloon in the lengthwise extended condition through extension of the piston.