Cryoablation of Anteroseptal Accessory Pathways in Children With Limited Fluoroscopy Exposure

Abstract

Due to its safety profile, cryoablation is used increasingly in pediatric patients, especially for septal arrhythmia substrates. Recent advances in electroanatomical-mapping technologies have resulted in a decrease or complete elimination of fluoroscopy exposure during catheter ablation procedures. The aim of this study was to assess the efficacy and safety of cryoablation of anteroseptal accessory pathways (APs) using electroanatomical-mapping system guidance with limited fluoroscopy exposure. A total of 24 patients underwent cryoablation of anteroseptal APs between July 2010 and April 2012. Cryomapping was performed with a 6 mm-tip catheter at -30 °C before the lesions were delivered. An 8 mm-tip catheter was used in one patient. The EnSite system (St. Jude Medical, St Paul, MN) was used in all procedures. The mean age was 11.9 ± 4.3 years. Acute success rate was 95.8 % (23 of 24). The mean procedure and cryoablation durations were 168 ± 58 min and 1,463 ± 525 s, respectively. Limited fluoroscopy was used only in 7 patients, and the mean fluoroscopy time was 1.7 ± 1.8 min (range 0.1-4 min) in these patients. Recurrence was noted in 2 patients (8.7 %) who underwent a second successful cryoablation procedure. The patient who underwent a failed attempt during the first procedure was successfully treated with a repeat procedure. The resultant long-term success rate was 100 % at a mean follow-up period of 14.2 ± 7.7 months. There were no complications except for transient atrioventricular block in one patient. Cryoablation of anteroseptal APs can be performed effectively and safely in children using a limited fluoroscopic approach with the help of electroanatomical-mapping systems.

Radiofrequency ablation of anteroseptal accessory pathway: A challenge to the electrophysiologist

“…Cryothermal ablation may be an alternative to RF ablation to reduces the risk of permanent block in septal arrhythmia substrates [12][13][14][15][16] . Due to its safety profile, cryoablation is used increasingly in pediatric patients.…”

“…Due to its safety profile, cryoablation is used increasingly in pediatric patients. The advantages of cryothermal energy is reversibility of lesions during cryomapping and increased catheter stability [12][13][14][15][16] . The target was usually identified using a steerable quadripolar electrophysiology catheter, marked as a point on the three-dimensional mapping system.…”

“…Cryomapping usually was performed at -30°C at the previously marked location. If AP block was achieved, ablation was continued for 240-360 ms at -70°C to -80°C to achieve the freeze effect [12][13][14][15][16] .…”

Tricking CARTO: Cryoablation of Supraventricular Tachycardia in Children with Minimal Radiation Exposure Using the CARTO3 System

“…This can be particularly problematic when using the CARTO3 system if cryoenergy (cryo) is needed for ablation. Cryo is often utilized as an energy source by many pediatric electrophysiologists due to the concern for atrioventricular (AV) nodal or coronary artery injury in children with small hearts . Because of its closed platform, many electrophysiologists using CARTO3 will typically resort to mapping and catheter visualization primarily via fluoroscopy (FLUORO) when a Medtronic Cryocatheter is required (Medtronic PLC, Minneapolis, MN, USA).…”

“…Cryo is often utilized as an energy source by many pediatric electrophysiologists due to the concern for atrioventricular (AV) nodal or coronary artery injury in children with small hearts. [8][9][10][11][12][13] Because of its closed platform, many electrophysiologists using CARTO3 will typically resort to mapping and catheter visualization primarily via fluoroscopy (FLUORO) when a Medtronic Cryocatheter is required (Medtronic PLC, Minneapolis, MN, USA). However, the CARTO3 system may be "tricked" to navigate through the chamber of interest with a cryoablation catheter.…”