Catheter Ablation -> Ventricular Arrhythmias -> Mapping & Imaging D-PO06 - Poster Session VI (ID 26) Poster

D-PO06-094 - Volume-weighted Unipolar Endocardial Voltage: An Excellent, Novel Parameter For Predicting Cardiac Mortality In Patients With Non-ischemic Cardiomyopathy And Ventricular Arrhythmias (ID 660)

Abstract

Background: Patients with non-ischemic cardiomyopathy (NICM) and ventricular tachyarrhythmias (VT) are at risk for cardiac death. Global left ventricular endocardial voltage may reflect the amount of excitable viable myocardium. A critical reduction of voltages may identify patients at risk for rapid progression to end-stage heart failure (HF).
Objective: The study evaluates whether the volume-weighted endocardial voltage, as surrogate for the total excitable viable myocardium, predicts mortality in patients with NICM and VT.
Methods: Consecutive patients with left-dominant NICM, who underwent high density endocardial voltage mapping (Thermocool™) and VT ablation (2012-2018) were included. Mapping data were transferred from CARTO to ParaView after excluding the valve areas. The volume-weighted unipolar and bipolar voltage (vwUV, vwBW) were calculated by mathematically integrating the UV and BV over the whole LV (thereby correcting for mapping density heterogeneity) divided by the endocardial LV surface area and corrected for echocardiographically determined wall thickness. The prognostic value of vwUV and vwBV for cardiac death were evaluated.
Results: One hundred three patients (age, 57±14yrs; LVEF, 39±13%; genetic variants 33 [32%]; amiodarone use 36 [35%]) were included. VwUV and vwBV were 9.94±3.42 and 4.70±1.46. During a median follow up of 24 months, cardiac mortality was 18% (end-stage HF 16/19, median time to death 5.7 months). Patients who died had a significantly lower vwUV and vwBV (vwUV 5.62±0.93 vs. 10.91±3.10, P<0.001; vwBV 2.99±0.70 vs. 5.04±1.28, P<0.001) The optimal cutoff of vwUV for predicting cardiac death was 6.82 (AUC, 0.96; Sensitivity, 89%; Specificity, 94%), superior to that of LVEF or vwBV (AUC, 0.80, 0.91, respectively). In multivariable Cox-regression analysis, vwUV remained the only significant predictor for cardiac death (for 1 decrease, HR 2.07, CI 1.27-3.53 P=0.03), independently of LVEF, LVA, vwBV, genetic variants and amiodarone use.
Conclusion: VwUV is a newly proposed surrogate for the amount of LV viable myocardium, available from routine endocardial mapping and an excellent parameter to identify patients at high risk for rapid progression to HF related death.
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