Multiple gas circuit connector and method for cryoablation system

A cryoablation system comprising:

• a working gas circuit;
• a vacuum chamber isolated from the working gas circuit;
• a shaft, the shaft comprising along a length of the shaft:
• an insulated zone along a proximal length of the shaft, comprising a vacuum chamber shaft portion and an insulated portion of the working gas circuit, wherein the vacuum chamber shaft portion surrounds and is isolated from the insulated portion of the working gas circuit;
• and
• a working gas expansion chamber distal to the insulated zone, wherein the working gas expansion chamber comprises an expansion portion of the working gas circuit;
• and
• a shaft-handle connector, wherein a proximal end of the shaft connects to the shaft-handle connector, wherein the shaft-handle connector is configured to removably attach the proximal end of the shaft to a distal end of a handle, wherein the shaft-handle connector further comprises:
• a working gas connector structure configured to make a sealed connection to a working gas supply passage in the handle and a working gas exhaust passage in the handle;
• a vacuum connector structure configured to make a sealed connection to a vacuum chamber portion of the handle;
• and
• wherein the shaft-handle connector comprises a connector portion of the vacuum chamber isolated from a connector portion of the working gas circuit.

A method of operating a cryoablation system comprising:

• providing a cryoablation system, the cryoablation system comprising:
• a working gas circuit;
• a first catheter assembly comprising a first shaft and a first shaft-handle connector, the first shaft comprising a first working gas expansion chamber;
• a handle comprising a handle portion of the working gas circuit;
• and
• wherein a proximal end of the first shaft connects to the first shaft-handle connector, wherein the first shaft-handle connector removably attaches the proximal end of the first shaft to a distal end of the handle;
• detaching the first catheter assembly from the handle;
• attaching a second catheter assembly to the handle, wherein the second catheter assembly comprises a second shaft and a second shaft-handle connector, the second shaft comprising a second working gas expansion chamber, wherein a proximal end of the second shaft connects to the second shaft-handle connector, wherein the second shaft-handle connector is configured to removably attach the proximal end of the second shaft to a distal end of the handle.