Background: Failed catheter-based ablation for the treatment of atrial fibrillation is an indication for the Cox-maze procedure. Many patients are referred for the Cox-maze IV procedure with recurrent atrial fibrillation after a previous catheter-based ablation, but the efficacy and safety of surgical management in these patients remains unclear. Methods: Data were collected prospectively on 129 consecutive patients who underwent a stand-alone Cox-maze IV procedure. Patients were grouped by the presence (n = 61; 47%) or absence (n = 68; 53%) of previous catheter ablation history. Follow-up was conducted at 3, 6, and 12 months (94% complete, mean 15.1 ± 15.6 months) with electrocardiograms and 24-hour Holter monitoring. Results: In patients with no ablation history compared with those with, freedom from atrial tachyarrhythmias and antiarrhythmic drugs were similar at 3 months (73% versus 67%), 6 months (85% versus 83%), and 12 months (81% versus 87%; p < 0.05 for all). Those who had failed previous catheter ablation had significantly smaller left atria and longer durations of atrial fibrillation, and were more likely to have persistent atrial fibrillation compared with the group without prior ablation history. All analyzed baseline patient characteristics and comorbidities were similar between the groups. No differences were found in complication rates or surrogate measures of operative difficulty. Conclusions: The Cox-maze IV procedure is safe and effective in treating recurrent atrial fibrillation regardless of previous catheter ablation history. Surgical management should be considered in patients who have failed catheter ablation for the treatment of their atrial fibrillation.