Introduction
The mechanism responsible for adenosine-sensitive atrial tachycardias
(ATs) originating from vicinity of the atrioventricular (AV) node has
been considered to be reentry1, and they could be
ablated safely at the entrance of the slow conduction zone (SCZ) remote
from the His bundle region, indicated by a manifest entrainment-guided
strategy.2,3 In this strategy, manifest entrainment is
defined by the orthodromic capture of the electrogram at the earliest
activation site (EAS) with a long conduction time by the immediately
previous pacing impulse (n-1), and the antidromic capture of other sites
by the immediate impulse (n) in one paced beat except for the last
entrained beat, equivalent to constant fusion. We described a case of
adenosine-sensitive AT originating from the para-Hisian region that
could be eliminated at a remote site from the EAS indicated by the
demonstration of manifest entrainment from the anteroseptal left atrium
(LA).