Catheter cryoablation guided by propagation mapping to treat dual atrioventricular nodal nonreentrant tachycardia in an adult with postoperative congenital heart disease

Dual atrioventricular node non-reentrant tachycardia (DAVNNRT) is an uncommon and often misdiagnosed arrhythmia reported in patients without congenital heart disease (CHD), leaving some patients with troublesome palpitations while causing tachycardia-induced cardiomyopathy in others (1,2). DAVNNRT results from unusual downstream conduction of consecutive sinus beats via multiple pathways into the AV node; each sinus impulse first penetrates the AVN via the "fast pathway" (FP), followed by an impulse from the same sinus beat conducting via the "slow pathway" (SP) (1,2).