H. Nakagawa et al., EARLY AFTERDEPOLARIZATIONS IN A PATIENT WITH IDIOPATHIC MONOMORPHIC RIGHT-VENTRICULAR TACHYCARDIA, PACE, 16(10), 1993, pp. 2067-2072
To identify the role of after depolarizations in the induction of idio
pathic monomorphic right ventricular tachycardia (VT), monophasic acti
on potentials (MAPs) were recorded in a patient with this type of VT.
The VT had a left bundle branch block configuration and inferior axis,
and originated in the right ventricular outflow tract (RVOT). MAPs we
re recorded with a contact electrode at the origin of the VT, as well
as other ventricular sites. The VT was induced by the intravenous admi
nistration of isoproterenol and/or rapid ventricular pacing and was pr
eceded by short-long-short sequences of RR intervals. Early after depo
larizations (EADs) in MAPs were recorded at the origin of VT (RVOT), b
ut not recorded at other ventricular sites. These data suggest that ca
techolamine sensitive triggered activity seems to be the mechanism of
idiopathic monomorphic right VT and EADs can be recorded in associatio
n with the occurrence of this type of VT.