Spontaneous left atrial reentry tachycardias : radiofrequency ablation and outcome

Spontaneous left atrial reentry tachycardias (LART) in patients without previous cardiac surgical or catheter ablation are rare. Several therapeutic concepts of catheter ablation have been suggested: linear lesions (LL), circumferential pulmonary vein isolation (PVI), and both (LL + PVI).

In all, 28 consecutive symptomatic patients with 51 LARTs presented to our institution for catheter ablation. Electroanatomical mapping was performed on 25 patients. Three patients were ablated conventionally during LART; 25 patients (89.3 %) had extensive low-voltage areas in the left atrium (atrial myopathy). One of the following ablation strategies was applied: first, LL (n = 8), second, PVI + LL (n = 11), and third PVI alone (n = 9). Fourteen patients (50 %) had a recurrent arrhythmia during a mean follow-up of 12.2 ± 11.1 months. Six patients presented with a recurrent LART (21.4 %), 4 with LART and atrial fibrillation (Afib) (14.3 %), and 4 with Afib (14.3 %). The recurrence rate of any arrhythmia (LART and Afib) was 37.5 % in the LL group, 44.4 % in the PVI group, and 63.6 % in the PVI + LL group (ns); the recurrence rate of LARTs was 12.5 % in the LL group, 22.2 % in the PVI group, and 63.6 % in the PVI + LL group (p < 0.05).

Atrial tachyarrhythmia recurrence after ablation of spontaneous LART in mid-term is considerable. Stable LARTs are effectively treated by LL. PVI alone may be an acceptable alternative, especially in patients with unstable LARTs and Afib. However, the risk of recurrent LARTs after a more extensive strategy with PVI and LL is considerable, probably due to proarrhythmic effects of long linear lesions.