Sheath with expandable distal extremity and balloon catheters and stents for use therewith and method

Claim 1

A sheath for advancement into a vessel of a body of a patient having a stenosis therein which at least partially occludes the flow of blood in the vessel and is for use with a plurality of balloon catheters having distal extremities with inflatable balloons thereon with the balloon on one of the plurality of catheters having an inflated size greater than the inflated size of another of the plurality of catheters comprising a flexible elongate tubular member formed of plastic and having proximal and distal extremities and having a lumen extending from the proximal extremity to the distal extremity sized to receive one at a time of said plurality of balloon catheters, a portion of the distal extremity of the flexible elongate tubular member overlying the region in which the inflatable balloon of one of the plurality of balloon catheters is normally positioned being formed so that it is radially expandable and means carried by the expandable portion for imparting pushability and column strength to the expandable portion and an attachment mounted on the proximal extremity of the flexible elongate tubular member, said flexible elongate tubular member having a length so that when the expandable portion is disposed in the stenosis, the proximal extremity with the attachment thereon is outside the body of the patient and the lumen in the proximal extremity is accessible for introduction of the balloon catheters into the lumen of the sheath one at a time from a location exterior of the body, the radial expansion of the distal extremity of the flexible elongate tubular member being caused by expansion of at least one of the inflatable balloons of the plurality of balloon catheters.

Claim 25

A method for forming a larger flow passage in a stenosis in a vessel in the body of a patient by the use of a guide wire, a plurality of balloon catheters having distal extremities with inflatable balloons thereon with the balloon on one of the catheters having an inflated size greater than the inflated size of another of the balloon catheters and a substantially imperforate sheath with an expandable distal extremity and having a lumen extending from the proximal extremity to the distal extremity and being sized to receive one at a time of said plurality of balloon catheters, a portion of the distal extremity of the flexible elongate tubular member being imperforate and being formed so that it is radially expandable, the sheath having a proximal extremity and an attachment secured to the proximal extremity and having a length ranging from 130-160 centimeters comprising the steps of advancing the guide wire through the stenosis, advancing the sheath with an expandable distal extremity over the guide wire from outside the body so that the expandable distal extremity is moved into registration with the stenosis while retaining the proximal extremity with the attachment thereon outside the body, advancing on of the balloon catheters into the sheath from outside the body so that the balloon thereon is in registration with the expandable portion of the sheath, inflating the balloon thereon to cause expansion of the expandable portion of the sheath to increase the size of the flow passage in the stenosis, deflating the balloon thereon and removing said one balloon catheter from the sheath and if required advancing another of the balloon catheters of a larger inflated size into the sheath from outside the body while the expandable portion of the sheath is still disposed within the stenosis, inflating the balloon of the another balloon catheter to cause expansion of the expandable portion to cause a still further enlargement of the flow passage through the stenosis, deflating the balloon of the another balloon catheter and removing the another balloon catheter from the sheath and removing the sheath.

Claim 26

A method for forming a larger flow passage in a stenosis in a vessel in the body of a patient by the use of a guide wire, a plurality of balloon catheters having distal extremities with inflatable balloons thereon with the balloon on one of the catheters having an inflated size greater than the inflated size of another of the balloon catheters and a substantially imperforate sheath with an expandable distal extremity and having a lumen extending from the proximal extremity to the distal extremity and being sized to receive one at a time of said plurality of balloon catheters, a portion of the distal extremity of the flexible elongate tubular member being imperforate and being formed so that it is radially expandable, the sheath having a proximal extremity and an attachment secured to the proximal extremity and having a length ranging from 130-160 centimeters comprising the steps of advancing the guide wire through the stenosis, advancing the sheath with an expandable distal extremity over the guide wire from outside the body so that the expandable distal extremity is moved into registration with the stenosis while retaining the proximal extremity with the attachment thereon outside the body, advancing on of the balloon catheters into the sheath from outside the body so that the balloon thereon is in registration with the expandable portion of the sheath, inflating the balloon thereon to cause expansion of the expandable portion of the sheath to increase the size of the flow passage in the stenosis, deflating the balloon thereon and removing said one balloon catheter from the sheath and if required advancing another of the balloon catheters of a larger inflated size into the sheath from outside the body while the expandable portion of the sheath is still disposed within the stenosis, inflating the balloon of the another balloon catheter to cause expansion of the expandable portion to cause a still further enlargement of the flow passage through the stenosis, deflating the balloon of the another balloon catheter and removing the another balloon catheter from the sheath and removing the sheath.