1.0 Introduction
CA with either radiofrequency (RF) energy or cryoenergy is a
well-establish therapy in treating SVT in both paediatric and adult
populations [1]. Traditionally, X-ray fluoroscopy is used during CA
procedures, though the utilisation of ionising radiation carries
non-negligible stochastic and deterministic risks to the health of both
the patient and the professional staff. These effects are cumulative and
behave in a linear no-threshold manner and, as such, are especially
important in paediatric populations [2]. The importance of reducing
ionising radiation exposure has been recognised by the American College
of Cardiology, which recommends the ALARA (as low as reasonably
achievable) principle in all interventional laboratories [3].
In recent years, advances in three-dimensional (3D) electroanatomical
mapping (EAM) systems and their utilisation have enabled the near-zero
and ZF approaches to be studied. In a recent multicentre randomised
trial investigating the near-zero approach in right- and left-sided SVT
ablation, reduction of fluoroscopy was achievable in all patients and
resulted in an estimated 96% reduction in overall risk of cancer
incidence and mortality. The study also estimated that the supplementary
cost associated with the addition of the 3D EAM system is justified when
increase in life expectancy and period of life without cancer are
considered [4]. However, most data regarding the feasibility,
safety, and efficacy of the ZF approach is available for right-sided SVT
only [5–8].
The aim of this study was to evaluate the safety and efficacy of ZF CA
for the treatment of SVTs in adult and paediatric populations in
comparison to the CF-based approach.