The Achieve mapping catheter allows real-time recordings from the pulmonary veins (PVs) during cryoballoon (CB) ablation of atrial fibrillation (AF). To assess the clinical applicability of the Achieve mapping catheter and the value of real-time recordings from the PVs during CB. Patients with paroxysmal AF undergoing CB ablation were studied. Recordings from the PVs were analyzed during (real-time recordings) and after CB ablation and validated by using a variable circumferential mapping catheter (Achieve group; n = 20). A comparison was made by using a group of patients in whom CB ablation with a guidewire and a variable circumferential mapping catheter was performed (Guidewire group; n = 20). Forty patients (age 58±11 years; ejection fraction 0.59±0.07; left atrial size 40±6 mm) with paroxysmal AF were included. In the Achieve group, real-time recordings from the PVs could be obtained in 40 of 80 (50%) PVs and could be seen more often at the left-sided PVs (25 of 39, 64%) than at the right-sided PVs (15 of 41, 37%; P = .02). Validation with a standard circumferential mapping catheter confirmed PV isolation in 75 of 80 (93%) PVs. After a single procedure and a follow-up of 14±4 months, 25 of 40 (63%) patients were in sinus rhythm with no significant difference between groups. The Achieve catheter can be used as a substitute for a guidewire during CB ablation, but real-time recordings can be obtained only in half of the PVs and are not sufficient to accurately confirm isolation of all PVs.