Outcome after tailored catheter ablation of atrial tachycardia using ultra‐high‐density mapping

Abstract

Introduction: Tailored catheter ablation of atrial tachycardias (ATs) is increasingly recommended as a potentially easy treatment strategy in the era of high-density mapping (HDM). As follow-up data are sparse, we here report outcomes after HDMguided ablation of ATs in patients with prior catheter ablation or cardiac surgery. Methods and Results: In 250 consecutive patients (age 66.5 ± 0.7 years, 58% male) with ATs (98% prior catheter ablation, 13% prior cardiac surgery) an HDM-guided catheter ablation was performed with the support of a 64-electrode mini-basket catheter. A total of 354 ATs (1.4 ± 0.1 ATs per patient; mean cycle length 304 ± 4.3 ms; 64% macroreentry, 27% localized reentry, and 9% focal) with acute termination of 95% were targeted in the index procedure. A similar AT as in the index procedure recurred in five patients (2%) after a median follow-up time of 535 days (interquartile range (IQR) 25th-75th percentile: 217-841). Tailored ablation of reentry ATs with freedom from any arrhythmia was obtained in 53% after a single procedure and in 73% after 1.4 ± 0.4 ablation procedures (range: 1-4). A total of 228 patients (91%) were free from any arrhythmia recurrence after 210 days (IQR: 152-494) when including optimal usual care. Conclusions: Tailored catheter ablation of ATs guided by HDM has a high acute success rate. The recurrence rate of the index AT is low. In patients with extensive atrial scaring further ablation procedures need to be considered to achieve freedom from any arrhythmia.

Ablation of Left Atrial Tachycardia following Catheter Ablation of Atrial Fibrillation: 12-Month Success Rates

“…We studied 35 recurrent AT patients with the high-resolution 3D electro-anatomical mapping system Rhythmia HDx TM in order to best confirm the hypothesized advantages of a standardized, algorithm-based ablation approach for complex arrhythmias resulting from potential benefits of complete mechanism traceability. Despite the availability of high-resolution 3D electro-anatomical mapping since several years ago, there is still no standardized terminology in the literature for whether macro-reentry tachycardias circle around a central obstacle of a certain size [24,41] or around an anatomical structure [42]. In this study, tachycardias circling around an anatomical structure were classified as macro-reentry.…”

“…In this study, tachycardias circling around an anatomical structure were classified as macro-reentry. The term "focal" was used in some studies [40][41][42] for both micro-reentry and true focal automatisms, making it difficult to compare reported incidences and success rates. Non-reentrant focal tachycardias may have so far not been mapped accurately enough and have therefore been difficult to differentiate from micro-reentry tachycardias [43].…”

“…ATs could be terminated in 74%, and the success rate after 6 months was 74%. Adapting and further developing this approach, Jungen et al reported 73% freedom from AT after seven months and a mean of 1.4 procedures per patient [41].…”

“…This demonstrates the need for a high-resolution catheter and raises the question of whether even an improved signalto-noise ratio would add additional information to the understanding of the arrhythmia. Jungen et al demonstrated high effectiveness and very low recurrence rates of CA in clinical tachycardia [41]. However, even if non-inducibility could be demonstrated at the end of the ablation, recurrencies of other arrhythmias were reported to be high.…”

Vascular entrapment of a multipolar basket catheter (OrionTM) during catheter ablation

“…The IntellaMap Orion basket catheter is the largest electrophysiology catheter available (22 mm when deployed, 64‐electrode, eight splines), allowing for ultrahigh‐density mapping‐based catheter ablation of complex cardiac arrhythmias 1,2 . However, its size and stiffness may complicate manipulation in the vascular system, 3 especially in case of anatomical variations such as venous valves, which are present in 26% of external iliac veins and 10% of internal iliac veins 4 .…”