Influence of baseline inducibility and activation mapping on ablation
outcomes in patients with structural heart disease and ventricular
tachycardia
Abstract
Introduction:Stand-alone substrate ablation without baseline ventricular
tachycardia (VT) induction and activation mapping has become a standard
VT ablation strategy. We sought to evaluate the influence of baseline VT
inducibility and activation mapping on ablation outcomes in patients
with structural heart disease (SHD) undergoing VT ablation. Methods:This
is a single center, observational and retrospective study including
consecutive patients with SHD and documented VT undergoing ablation.
Baseline VT induction was attempted before ablation in all patients and
VT activation mapping performed when possible. Ablation was guided by
activation mapping for mappable VTs plus substrate ablation for all
patients. Ablation outcomes and complications were evaluated. Results:
160 patients were included (203 VT ablation procedures) and were
classified in 3 groups according to baseline VT inducibility: group 1
(non inducible, n=18), group 2 (1 VT morphology induced, n=53), and
group 3 (>1VT morphology induced, n=89). VT activation
mapping was possible in 35%. After a median follow-up of 38.5 months,
baseline inducibility of >1VT morphology was associated
with a significant incidence of VT recurrence (42% for group 3 vs.
15.1% for group 2 and 5.6% for group 1, Log-rank p<0.0001)
and activation mapping with a lower rate of VT recurrence (24% vs.
36.3%, Log-rank p=0.035). Independent predictors of VT recurrences and
mortality were baseline inducibility of >1VT morphology (HR
12.05 IC 95% 1.60-90.79, p=0.016) and LVEF<30% (HR 2.43 IC
95% 1.45-4.07, p=0.001), respectively. Complications occurred in 11.2%
(5.6% hemodynamic decompensation). Conclusions:Baseline VT inducibility
and activation mapping may add significant prognostic information during
VT ablation procedur