Rotational atherectomy device with electric motor

A rotational atherectomy system, comprising:

• an elongated, flexible drive shaft having a distal end for insertion into a vasculature of a patient and having a proximal end opposite the distal end remaining outside the vasculature of the patient;
• an eccentric solid crown attached to the drive shaft proximate the distal end of the drive shaft;
• an electric motor rotatably coupled to the proximal end of the drive shaft, the electric motor being capable of rotating the drive shaft in a first direction and in a second direction opposite the first direction;
• a handle housing the electric motor;
• control electronics for monitoring and controlling the rotation of the electric motor, the control electronics that detect when the drive shaft and eccentric solid crown encounter a blockage in the vasculature that rapidly slows their rotation and control the rotational speed and torque of the drive shaft in response to the blockage;
• and
• a control unit separate from the handle and electrically tethered to the handle.

A rotational atherectomy system, comprising:

• an elongated, flexible drive shaft having a distal end for insertion into a vasculature of a patient and having a proximal end opposite the distal end remaining outside the vasculature of the patient;
• an eccentric solid crown attached to the drive shaft proximate the distal end of the drive shaft;
• an electric motor rotatably coupled to the proximal end of the drive shaft, the electric motor being capable of rotating the drive shaft in a first direction and in a second direction opposite the first direction;
• and
• control electronics for monitoring and controlling the rotation of the electric motor;
• wherein the drive shaft and eccentric solid crown, when rotating, have a torque limited by a current supplied to the electric motor;
• wherein the control electronics detect when the drive shaft and eccentric solid crown encounter a blockage in the vasculature that rapidly slows their rotation and control the rotational speed and torque of the drive shaft in response to the blockage;
• wherein the control electronics include limits on maximum and minimum rotational speeds of the electric motor;
• wherein the control electronics include limits on maximum and minimum current supplied to the electric motor;
• wherein the control electronics include limits on maximum and minimum torque delivered by the electric motor;
• and
• wherein the control unit includes a void detector that ensures reliable delivery of saline to the vasculature of the patient.

A rotational atherectomy system, comprising:

• an elongated, flexible drive shaft having a distal end for insertion into a vasculature of a patient and having a proximal end opposite the distal end remaining outside the vasculature of the patient;
• an abrasive element attached to the drive shaft proximate the distal end of the drive shaft;
• an electric motor rotatably coupled to the proximal end of the drive shaft, the electric motor being capable of rotating the drive shaft;
• and
• control electronics for monitoring and controlling the rotation of the electric motor, the control electronics including an algorithm for limiting the torque on the drive shaft when the abrasive element encounters an obstruction and ceases rotation, the algorithm comprising:
• detecting a decrease in the rotational speed of the electric motor;
• and
• releasing the motor, thereby allowing the motor to spin freely as a flywheel.