Figure.

Patient flow, including planned sample size recalculation. *The initial sample size calculation resulted in 244 patients, which was readjusted in March 2011 after a prespecified blinded sample size recalculation (see Methods). Patients (pts) withdrawing consent before treatment (tx) were unaware of the assignment and were excluded from the population. Patients who refused a 12-month follow-up were contacted by phone to verify that they were alive although no heart rhythm was obtained. CB indicates cryoballoon ablation; FU, follow-up; ITT, intention to treat; PP, per protocol; and RF, radiofrequency catheter ablation.