A cryoablation method, system, and device that allows for real-time and accurate assessment and monitoring of PV occlusion and lesion formation without the need for expensive imaging systems and without patient exposure to radiation. The system includes a cryoballoon catheter with a cryoballoon, a distal electrode, a proximal electrode, and a temperature sensor. Impedance measurements recorded by the electrodes may be used to predict ice formation, quality of pulmonary vein occlusion, and lesion formation.
