Diagram summarizing types of ATs often encountered in patients with a his- tory of atrial fibrillation, including those seen after catheter or surgical ablation procedures. P-wave morphologies are shown for common types of atrial flutter; however, the P-wave morphology is not always a reliable guide to the re-entry circuit location or to the distinction between common atrial flutter and other macroreentrant ATs. *Exceptions to P-wave morphology and rate are common in scarred atria. bpm indicates beats per minute, and ECG, electrocardiogram. Reproduced with permission from January et al.10 SVT or tachycardia-induced cardiomyopathy or before sur- gery that may limit access for subsequent catheter-based pro- cedures. Recurrence rates for SVT after successful procedures are higher than reported in large adult series, ranging from 7% to 17%; whether this reflects technical differences, natural his- tory, or more long-term follow-up is unclear.427 429 Recurrence is highest among right-sided accessory pathways, particularly anteroseptal or multiple pathways, and in AT in the setting of complex congenital heart disease.427 429 Junctional ectopic tachycardia occurs predominantly in very young patients either as a congenital form or, more commonly, after intracardiac repair of congenital heart dis- ease. 