The purpose of this study was to investigate the association between the distribution of low-voltage areas and the type of induced atrial tachyarrhythmias.
Our prospective observational study enrolled 152 consecutive AF patients scheduled for an initial ablation (46% persistent AF). After pulmonary vein isolation, voltage mapping was performed during sinus rhythm, and regions with reduced electrogram amplitudes (<0.5 mV) were defined as low-voltage areas. Burst pacing was performed to investigate the inducibility of atrial tachyarrhythmias.
Low-voltage areas were more frequently observed in patients with persistent AF than paroxysmal AF (50% vs 34%, P = .048). A higher proportion of patients with low-voltage areas presented with inducibility of atrial tachyarrhythmias than those without, as follows: AF 70% vs 16% (P = .0001); perimitral macroreentrant atrial tachycardia (AT) 18% vs 0% (P = .0001); and roof-dependent macroreentrant AT 13% vs 0% (P = .01). Investigation into the regional distribution of low-voltage areas revealed that patients with perimitral macroreentrant AT more frequently coincided with low-voltage areas than those without in the septal (100% vs 18%, P <.0001) and anterior regions (55% vs 11%, P = .001), and those with roof-dependent AT in the roof (75% vs 15%, P <.0001) and posterior regions (75% vs 15%, P = .0001).
Low-voltage areas are associated with high inducibility of atrial tachyarrhythmias after pulmonary vein isolation. In addition, the distribution of low-voltage areas is specific for each type of macroreentrant AT.