To evaluate the effect of electro-anatomical mapping on success rate and fluoroscopy time in ablation of supraventricular tachycardia substrates in a large group of children.

Patients referred from multiple centres in the Netherlands and who received a first ablation for supraventricular tachycardia substrates in the Leiden University Medical Center between 2014 and 2020 were included in this retrospective cohort study. They were divided in procedures in patients with fluoroscopy and procedures in patients using electro-anatomical mapping.

Outcomes of ablation of 373 electro-anatomical substrates were analysed. Acute success rate in the fluoro-group (n = 170) was 95.9% compared to 94.5% in the electro-anatomical mapping group (n = 181) (p = 0.539); recurrence rate was 6.1% in the fluoro-group and 6.4% in the electro-anatomical mapping group (p = 0.911) after a 12-months follow-up. Redo-ablations were performed in 12 cases in the fluoro-group and 10 cases in the electro-anatomical mapping group, with a success rate of 83.3% versus 80.0%, resulting in an overall success rate of 95.9% in the fluoro-group and 92.8% in the electro-anatomical mapping group (p = 0.216) after 12 months. Fluoroscopy time and dose area product decreased significantly from 16.00 ± 17.75 minutes (median ± interquartile range) to 2.00 ± 3.00 minutes (p = 0.000) and 210.5 µGym2 ± 249.3 to 32.9 µGym2 ± 78.6 (p = 0.000), respectively. In the fluoro-group, four complications occurred (2.0%) and in the electro-anatomical mapping group no complications occurred.

These results demonstrate that ablations of supraventricular tachycardia substrates in children remain a highly effective and safe treatment after the introduction of electro-anatomical mapping as a standard of care, while significantly reducing fluoroscopy time and dose area product.

Synchronized cardioversion is an internationally accepted standard therapy for unstable tachyarrhythmias, but it is conventionally an in-hospital physician-led intervention. Increasingly, it is being brought forward into the prehospital setting as part of a specialist paramedic scope of practice; however, very little literature exists regarding the epidemiology or efficacy in this setting.

All patients receiving cardioversion within a United Kingdom (UK) ambulance service were identified using an electronic database. The period of inclusion was March 1, 2017 through October 31, 2020. These data were then interrogated to provide demographic, physiological, and efficacy data, and then a sub-group was created to identify those who presented with a primary arrhythmia (as opposed to post-cardiac arrest).

From a total of 93 patients, prehospital synchronized cardioversion successfully terminated the tachyarrhythmia in 96% of patients presenting with a primary arrhythmia (85% in the allcomers group) with a predominance towards males (82% of patients) and an average age of 67 years. Hypotension and reduced level of consciousness were the most commonly documented unstable features (84.4% and 44.4%).

Cardioversion within a paramedic-led service results in efficacy rates of 96% in patients presenting with a primary tachyarrhythmia. This is a similar efficacy rate to traditional doctor-led therapies. Demographic data show that males make up over 80% of the patient population, in keeping with previously published work across the spectrum of cardiac interventions.