Termination of atrial fibrillation (AF) to atrial tachycardia (AT) is frequently observed during AF ablation, especially when substrate ablation is performed. The stepwise ablation approach aims at terminating AF to either AT or sinus rhythm. Most patients are terminated to AT rather than sinus rhythm. ATs are common during or after persistent AF ablation. To succeed in ablation of AT, its mechanism must be identified and the tachycardia circuit or origin mapped. In many cases, the mechanism of AT following AF ablation is macroreentry. Herein the strategy to map macroreentrant AT without using a 3-dimensional mapping system is described.