Background：Antidromic reentrant tachycardia(ART), in which an accessory atrioventricular pathway is used as the anterograde limb of an atrioventricular reentrant tachycardia, has been documented
clinically in less than 10% of patients with the Wolff-Parkinson-White(WPW) syndrome. The wide
QRS complex makes the distinction between antidromic AV reentrant tachycardia and ventricular tachycardia somewhat difficult. The purpose of this study is to evaluate the clinical and electrophysiologic
characteristics of the antidromic reentrant tachycardia.
Methods and Results：During the electrophysiologic study of 355 patients, from December 1986
to April 1995, referred for evaluation of Wolff-Parkinson-White syndrome, 18(5.1%) patients had
preexcited reciprocating tachycardia.
1) The age of the antidromic reentrant tachycardia patients ranged from 15 to 53 years(28±12),
and the mean age was younger than that of orthodromic reentrant tachycardia(ORT) patients(p<0.05).
2) Thirteen were male patients, five were females.
3) There were associated heart diseases in 3 cases. Two patients had Ebstein’s anomaly and one
had valvular heart disease.
4) The locations of accessory pathways(APs) documented on surface ECG were 7 left side(39%),
9 right side(50%), 1 posteroseptal side(5.5%) and 1 anteroseptal side.
5) Multiple bypass tracts were documented by electrophysiologic study in 7/18(38.9%) cases with
ART, more common than cases with ORT(20/337(5.9%))(p<0.05).
6) 25 accessory pathways were documented by EPS in 18 patients(10 left side, 11 right side, 2
posteroseptal side and 2 anteroseptal side). ART patients had more right sided AP(11/25, 44%) than
those with ORT(98/357, 27.5%), but ART patients had less posteroseptal AP(2/25, 8%) than those
with ORT(63/357, 17.6%).ope
