Aspiration thrombectomy system and methods for thrombus removal with aspiration catheter

A thrombectomy aspiration system, comprising:

• a vacuum source;
• a vacuum line fluidically coupled to the vacuum source;
• a vent line configured to be fluidically coupled to a vent fluid source;
• a valve system having a base, a housing, a vacuum valve within the housing and coupled to the base, and a vent valve within the housing and coupled to the base, wherein vacuum source is outside of the housing containing the vacuum valve and the vent valve such that the valve system is located apart from the vacuum source;
• an aspiration catheter having a proximal end coupled to the valve system such that the valve system is proximate to the catheter;
• and
• a controller configured to open and close the vacuum valve and the vent valve in a predetermined sequence to change a level of vacuum at a distal end of the aspiration catheter and to impart a controlled amount of exit flow out from the distal end of the catheter.