Catheter ablation of atrial tachyarrhythmias in patients with atrioventricular septal defect

Figures

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  Figure 1. Classifications of atrial tachyarrhythmias during first catheter ablation procedure. A non-clinical tachyarrhythmia was defined as a tachyarrhythmia induced during the procedure but not documented before the procedure. The tachyarrhythmia was considered as undetermined when the degree of confidence was too low to determine if the arrhythmia was clinical or not. The ablation was considered as prophylactic if an ablation line was created to trans-sect a potential isthmus without clinically or inducible tachyarrhythmia involving this isthmus. The term ‘other’ was used to re-group various circuits of IART or FAT, which did not involve the cavo-annular isthmus or the right lateral atriotomy. When the same patient had several other forms of arrhythmia, only one ‘other’ case was represented. AF, atrial fibrillation; CAI, cavo-annular isthmus; IART, intra-atrial re-entrant tachycardia; FAT, focal atrial tachycardia.

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  Figure 2. Most common circuits of IARTs in patients with AVSD. (A) Cavo-annular-dependent flutter in a patient with AVSD in LAO (left) and LAO inferior (right) views. Yellow dots denote the postero-inferiorly displaced His signal. Red dots denote RF applications creating a relatively lateral ablation line between the inferior vena cava and the annulus to minimize the risk of AV node injury. (B) Double loop circuit with a loop around the right AV annulus and a loop around the atriotomy in RAO (left) and left lateral/septal (right) views. An ablation line was created between the annulus and the inferior vena cava, and another lesion was made between the atriotomy scar and the inferior vena cava. AVSD, atrioventricular septal defect; AV, atrioventricular; IART, intra-atrial re-entrant tachycardia; LAO, left anterior oblique; RAO, right anterior oblique; RF, radio frequency.

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  Figure 3. Freedom from atrial arrhythmia recurrence after the first catheter ablation. Kaplan–Meier survival curves from first catheter ablation to first documented episode of atrial arrhythmia recurrence in the whole population (black), in patients with an IART (red) or AF (blue) targeted during the procedure. AF, atrial fibrillation; IART, intra-atrial re-entrant tachycardia.