Prediction of Primary Slow-Pathway Ablation Success Rate according to the Characteristics of Junctional Rhythm Developed during the Radiofrequency Catheter Ablation of Atrioventricular Nodal Reentrant Tachycardia

and congratulate them on their publication. There are some points in the aim of their study, method, and results, however, which I believe require further clarification. 1. The Introduction states that " Thus far, the most conventional marker and end point for successful radiofrequency (RF) ablation has been considered the loss of the inducibility of atrioventricular nodal reentrant tachycardia (AVNRT); be that as it may, it has been reported to be not inducible in up to 10% of patients. This disadvantage has prompted scientists to focus on identifying an accurate alternative end point for predicting the success rate of the slow-pathway RF ablation of AVNRT. " Also, the Discussion somehow repeats that: " Loss of the inducibility of AVNRT has been considered the end point for successful slow-pathway RF ablation; however, AVNRT is not inducible in up to 10% of patients during ablation. Nowadays, JR developed during the slow-pathway RF ablation of AVNRT has been identified as a sensitive surrogate end point for successful AVNRT ablation ". I take from these statements that given the unfeasibility of AVNRT induction in 10 % of cases during the electrophysiology (EP) study in conjunction with the clinical presence of arrhythmia (and probably other factors that convince the operator that the patient's clinical arrhythmia is most probably AVNRT), when the operator decides to ablate the slow pathway, the presence of JR during ablation can be a surrogate for non inducibility. Nevertheless, in this article this is not the case. As the esteemed authors have mentioned in all their cases, arrhythmia was inducible and non inducibility was their gold standard for successful ablation. It is known that the 12-lead surface electrocardiogram (ECG) can only be suggestive of AVNRT, and after the completion of EP study and appropriate maneuvers can the diagnosis be confirmed. 2 All the authors' patients, therefore, must have had inducible arrhythmia and the above-mentioned sentences in the Introduction and Discussion seem unrelated to this study and its stated aims. Investigation into the said issues would require another study design whereby-for example-in a group of patients with documented supraventricular tachycardia (SVT) compatible with AVNRT but non-inducible in the EP laboratory, the effect of ablation and presence of JR during ablation could be studied in other surrogates such as evidence of dual physiology or even the clinical outcome. 2. In their ablation technique, the esteemed authors report that after each RF application, inducibility was …