Abstract: In a rotational intravascular catheter, a proximal section of the catheter sheath, within which an elongated flexible drive member portion of the catheter is movably disposed, is extended into a telescoping portion of the catheter. The proximal sheath section functions to support the section of the drive member positioned within the telescoping section whether the telescoping section is in an extended position, qa retracted position, or any position therebetween.

Abstract: In a rotational intravascular catheter, a proximal section of the catheter sheath, within which an elongated flexible drive member portion of the catheter is movably disposed, is extended into a telescoping portion of the catheter. The proximal sheath section functions to support the section of the drive member positioned within the telescoping section whether the telescoping section is in an extended position, qa retracted position, or any position therebetween.

Abstract: An intravascular catheter has a telescope section including telescoped inner and outer tubular catheter members, a sheath having a proximal end anchored to an end of one of the inner and outer catheter members, and an elongated flexible drive member coaxially disposed within and being proximally and distally movable through the sheath. The drive member has a distal portion received in the sheath, and a second, unsheathed portion extending beyond the sheath into the interior of the telescope section. the unsheathed portion of the drive member has a stiffness greater than that of the sheath-disposed distal portion of the drive member and of a sufficient magnitude such that the unsheathed portion of the drive member is self-supporting within the telescope section.