Atherectomy device and method

A medical device, the medical device comprising:

• an outer tubular member made from one or more rigid materials having a first bend element and a second bend element, the second bend element being proximal to the first bend element in a natural state;
• a drive shaft and a rotatable treatment member configured to be accommodated in the outer tubular member;
• the treatment member on a distal end of the drive shaft, the treatment member configured to rotate and grind a substance inside a body lumen by rotating about a central axis, the treatment member including a distal-most end portion, a proximal end portion, and an intermediate portion positioned axially between the distal-most end portion and the proximal end portion, the distal-most end portion, the proximal end portion, and the intermediate portion being configured to be exposed from a distal end of the outer tubular member and to grind the substance inside the body lumen, and wherein the distal-most end portion includes a distally tapering portion and a proximally tapering portion, the proximally tapering portion being proximal of the distally tapering portion, and an intermediate portion of the distal-most end portion located between the distally tapering portion and the proximally tapering portion of the distal-most end portion;
• and
• wherein a distal end surface of the treatment member is configured to be directed toward a central axis of a vessel.

A medical device, the medical device comprising:

• an outer tubular member made from one or more rigid materials having a first bend element including a distal end portion of the outer tubular member and a second bend element, the second bend element being proximal to the first bend element in a natural state;
• a drive shaft configured to be accommodated in the outer tubular member;
• a rotatable treatment member on a distal end of the drive shaft, the treatment member configured to rotate and grind a substance inside a body lumen, the treatment member including a distal-most end portion, a proximal end portion, and an intermediate portion positioned axially between the distal-most end portion and the proximal end portion, and wherein the distal-most end portion includes a distally tapering portion and a proximally tapering portion proximal of the distally tapering portion, the distally tapering portion tapers toward a distal-most end of the treatment member, the proximally tapering portion tapers toward the proximal end portion, and the intermediate portion tapers toward the distal-most end of the treatment member from a proximal-most end of the intermediate portion to a distal-most end of the intermediate portion;
• and
• a bearing between the outer tubular member and the drive shaft, the bearing being positioned distal to the first bend element.