Methods, devices and systems for slow rotation of drive shaft driven atherectomy systems

A method of performing rotational atherectomy with controlled alternating rotational directions, comprising:

• providing an atherectomy device with a rotational driver,
• providing a drive shaft comprising wire filars, the drive shaft in operative connection with the rotational driver, and
• providing a rotational controller in operative communication with the rotational driver,
• providing a pulse-width modulator (PWM) that is in operational communication with the rotational controller and with the rotational driver and adapted to receive signals from the rotational controller, the PWM further adapted to generate PWM signals based on the received signals from the rotational controller,
• wherein the generated PWM signals are sent to the rotational driver to control the rotational driver's rotational direction and rotational speed;
• inserting the drive shaft into a blood vessel;
• controlling, with the generated PWM signals, the rotational direction and rotational speed of the rotational driver and drive shaft to initiate rotating in a first rotational direction;
• controlling, with the generated PWM signals, the rotational direction and rotational speed of the rotational driver and drive shaft to initiate rotating in a second rotational direction;
• and
• after the rotating is initiated in the first and second rotational directions, with the generated PWM signals, alternating between controlling driving of the rotational driver and rotation of the drive shaft in the first rotational direction and controlling driving of the rotational driver and rotation of the drive shaft in the second rotational direction.