A catheter based delivery system may be used for both therapeutic and diagnostic applications. The catheter based delivery system includes a catheter having a distal end. The distal end of the catheter includes several electrodes that can emit a radio frequency waveform, and may receive a signal representative of an impedance of material in the exposed to the radio frequency waveform. The radio frequency waveform may also be applied to ablate specifically targeted material exposed to the radio frequency waveform. The several electrodes may be configured as an antenna.