To the Editor—Response: Orthodromic reciprocating tachycardia

Abstract

We would like to thank the author for the kind comments. We agree with the author that care needs to be taken when assessing electrocardiographic (ECG) morphologies. All 12 ECG leads would need to be reviewed carefully to ascertain the first purely paced right ventricular (RV) beat or fixed fusion RV beat. However, in most of our cases of orthodromic reciprocating tachycardia (ORT), the tachycardia cycle length (TCL) was advanced to the paced cycle length (PCL) even before achieving fixed fusion in patients with right-sided as well as septal accessory pathways (AP). 1 Dandamudi G. Mokabberi R. Assal C. et al. A novel approach to differentiating orthodromic reciprocating tachycardia from atrioventricular nodal reentrant tachycardia. Heart Rhythm. 2010; 7: 1326-1329 Abstract Full Text Full Text PDF PubMed Scopus (55) Google Scholar However, this was not the case in any of the atrioventricular nodal reentry tachycardia (AVNRT) patients. Therefore, this difference makes it less likely to result in erroneous interpretation. However, this may be more of an issue with left lateral APs, in which usually the first fixed RV fusion beat results in acceleration of the TCL to the PCL. To the editor: Differentiating orthodromic reciprocating tachycardia from atrioventricular nodal reentrant tachycardiaHeart RhythmVol. 8Issue 3PreviewI read the article by Dandamudi et al1 with great interest. Congratulations for exploiting a very well known phenomenon in the electrophysiology laboratory and setting up criteria on the basis of that, and then validating this on a good number of patients to differentiate orthodromic reciprocating tachycardia (ORT) and atrioventricular nodal reentrant tachycardia (AVNRT). A few points are worth mentioning. Full-Text PDF