Relationship between non-pulmonary vein trigger sites and low voltage area

We previously reported that non pulmonary vein (PV) triggers of atrial fibrillation (AF) arose from low voltage area (LVA) in the left atrium (LA). However, the relationship between non-PV trigger sites and LVA is not fully clarified. The purpose of this study was to analyze the relationship between non-PV trigger sites and LVA per non-PV trigger site.

We enrolled 135 non-PV trigger positive AF cases. Relationship between trigger sites and LVA was evaluated.

Among the studied population, 59 paroxysmal AF cases (43.7%) and 70 multiple session cases (51.9%) were enrolled. One-hundred and four cases (77%) had 1 non PV trigger while 31 cases (23%) had multiple non PV triggers. LA voltage mapping was performed in 90 out of 135 cases. Relationship between trigger sites and LVA was evaluated in 96 LA non-PV trigger sites. While almost all of the anterior/roof trigger sites arose from LVA, half of the posterior/septum/inferior trigger sites arose from intact area (Fig. 1). None of the 6 right atrial (RA) non-PV trigger cases had LVA in the LA. We divided patients into 4 non-PV trigger groups (thoracic vein, RA, septum and LA group) and compared mid-term clinical outcome. Among the 4 groups, atrial tachyarrhythmia recurrence free rate at the 12 months of follow-up period was lowest in LA group (P<0.05) (Fig. 2).

Non-PV trigger sites are related to LVAs especially in the LA roof and anterior wall, and rather in the posterior/septum/inferior. The voltage mapping pattern may help to detect non-PV trigger sites.Figure 1Figure 2