Long-term Outcome of Ventricular Tachycardia Ablation in Patients who
did not Undergo Programmed Electrical Stimulation after Ablation
Abstract
Background: Ventricular arrhythmia inducibility is one of the ideal
endpoints of ventricular tachycardia(VT) ablation. However, it may be
challenging to implement programmed electrical stimulation (PES) at the
end of the procedure under several circumstances. The long-term outcome
of patients who did not undergo PES after VT ablation remains largely
unknown. Purpose: To investigate the details and long-term outcome of VT
ablation in patients who did not undergo PES at the end of the ablation
procedure. Methods: Among 184 VT ablation procedures in patients with
structural heart disease who underwent VT ablation using an irrigated
catheter, we enrolled those who did not undergo PES after VT ablation.
VT ablation strategy involved targeting induced VT plus pacemap-guided
substrate ablation if inducible. If VT was not inducible,
substrate-based ablation was performed. The primary endpoint was VT
recurrence. Results: In 58 procedures, post-ablation VT inducibility was
not assessed. The causes were non-inducibility of sustained VT before
ablation(27/58, 46.6%), long procedure time(27.6%, mean 392 min),
complications(10.3%), intolerant hemodynamic state(10.3%), and
inaccessible or unsafe target(6.9%). With regard to the primary
endpoint, 23 recurrences(39.7%) were observed during a mean follow-up
period of 2.5 years. Patients with non-inducibility before ablation
showed less VT recurrences(4/27, 14.8%) during follow-up than patients
with other causes of untested PES after ablation(19/31,
61.2%)(Log-rank<0.001). Conclusions: VT recurrence was not
observed in approximately 60% of the patients who did not undergo PES
at the end of the ablation procedure. PES after VT ablation may be not
needed among patients with pre-ablation non-inducibility.