area using this electrode configuration will achieve ablation to a depth of approximately 0 1 u2013 2 5 mm after reaching this ablation depth the impedance of the tissue will become so great that ablation will self terminate as described with respect to the operation of the system the proximal end of lumen 18 bifurcates into two sections of tubing 34 36 first section 34 terminates at a vacuum relief valve 38 that regulates the vacuum level within the catheter second section 36 terminates at a flush port 40 that is connectable to a source of saline or other fluid that may be injected into the vein via perforations 30 flush port 40 may also be coupled to a vacuum monitoring circuit 48 which detects the pressure within the lumen 16 18 so as to monitor to amount of vacuum applied in one embodiment the vacuum pump 46 and vacuum monitoring circuit 48 may be housed within the rf controller 44 as shown in fig2 a plurality of pores perforations 30 is formed in the catheter body 12 between balloons 20 as shown if the array is formed of a mesh the perforations may be the interstices of the mesh the perforations are fluidly coupled to fluid lumens 16 18 u2014 which may be contiguous with one other at the distal portion of the catheter body the proximal end of lumen 16 terminates at a suction port 32 that is connectable to a vacuum pump 46 thus application of a vacuum to lumen 16 draws moisture and fluid through the perforations 30 through lumen 16.