Post-procedural inducibility and the need for ICD implantation after VT ablation in structural heart disease with mild to moderately reduced ejection fraction

Introduction Structural heart disease increases the risk of ventricular tachycardia (VT) and sudden cardiac death. Catheter ablation reduces VT recurrence, and noninducibility at the end of the procedure may help identify patients in whom ICD implantation can be safely deferred. ILR or PPM implantation can support rhythm monitoring. Purpose To evaluate outcomes in patients with cardiomyopathy (CM) and mildly to moderately reduced LVEF undergoing VT ablation, focusing on VT recurrence, death, redo ablation, and the predictive value of post-procedural inducibility. Method Patients undergoing first VT ablation between 2019–2024 were prospectively enrolled. Inclusion criteria were structural heart disease (ischemic or non-ischemic), LVEF ≥35%, and ≥3 months of follow-up. Inducibility was assessed at the beginning and end of the procedure. ICD or ILR implantation was recommended but guided by shared decision-making. Outcomes included VT recurrence, ICD shock, redo ablation, and death, compared by end-procedural inducibility. Results Sixty-three patients (mean age 67±11 years; 92% male; LVEF 49±9%) underwent VT ablation with a median follow-up of 385 days (IQR 211–559). Cardiomyopathy was ischemic in 27 (42.9%), non-ischemic in 21 (33.3%), and mixed in 15 (23.8%). Forty patients (63%) had an ICD at baseline. VT reinduction was performed in 55 (87%) with a noninducibility rate of 70%. Among 44 noninducible patients, mean LVEF was 49±8%, ischemic CM was most common (20, 45.5%), and 27 (61%) had an ICD at baseline. Post-ablation, 5 (29%) received an ICD (median 3 days), 5 (29%) an ILR (median 10 days), 2 already had a PPM, and 1 received a PPM at 6 months. Five patients (8%) had no form of CIED. Among 11 inducible patients, mean LVEF was 51±10%, non-ischemic CM predominated (9, 47.7%), and 8 (73%) had an ICD at baseline. All three without an ICD received one during the index hospitalization. Eight additional patients did not undergo repeat induction due to procedural duration or hemodynamic instability. Of these, 5 (63%) had an ICD at baseline, 2 (25%) were implanted during follow-up, and 1 declined device therapy. Non-inducibility vs any inducibility or induction not performed was associated with a higher risk of VT recurrence (HR 3.75, 95%CI 1.55–9.05, p=0.003) and the composite endpoint (HR 2.66, 95%CI 1.21–5.83, p=0.015). Conclusion In patients with structural heart disease and LVEF ≥35%, post-procedural inducibility was strongly associated with worse outcomes. Tailoring ICD implantation to inducibility status in conjunction with shared decision-making appears to be a reasonable individualized strategy after VT ablation.