Clinical Electrophysiology -> Ventricular Arrhythmias -> Quality Measures & Complications D-PO06 - Poster Session VI (ID 26) Poster

D-PO06-059 - A Novel Unipolar To Bipolar Low Voltage Area Ratio To Identify Patients With Non Ischemic Cardiomyopathy And Infero Lateral Substrate With Favorable Response To Endocardial Only Ablation (ID 690)


Background: Epicardial (EPI) ablation is often required in patients with non-ischemic cardiomyopathy (NICM) and infero-lateral substrate owing to the high prevalence of EPI substrate in this group. In select cases, an endocardial (ENDO)-only approach is sufficient to achieve long-term VT control, and the identification of these patients is important.
Objective: We evaluated whether the ENDO unipolar to bipolar low voltage area ratio can predict successful ENDO-only ablation in NICM with infero-lateral substrate.
Methods: We included 149 consecutive patients (age 58±13 years, 80% males) with NICM and infero-lateral substrate. All patients underwent ENDO substrate mapping with analysis of low bipolar/unipolar voltage according to established cut-off values. A total of 68 (46%) patients underwent adjunctive EPI mapping/ablation for recurrent VT or persistent inducibility after ENDO-only ablation.
Results: At 1-year follow-up, a total of 81 patients (54%) had a favorable response to ENDO-only ablation with no documented VT recurrence following ENDO-only ablation. These patients had a larger ENDO bipolar scar area [34 (18-68) vs. 15 (7-38) cm2; p=0.01], with a similar extent of ENDO unipolar low voltage [43 (26-82) vs 34 (16-79) cm2; p=0.6] compared to the ENDO-EPI group. A ratio between ENDO unipolar scar area/bipolar scar area ≤1.5 was able to identify patients who responded favorably to ENDO-only ablation with a positive predictive value of 79% and a negative predictive value of 74%.
Conclusion: A ratio unipolar/bipolar scar area ≤1.5 identifies patients with NICM and infero-lateral substrate that have a favorable outcome with ENDO-only ablation.