Late gadolinium enhancement dispersion mapping for predicting arrhythmic events in patient with dilated cardiomyopathy

Purpose: In non-ischemic dilated cardiomyopathy (DCM) prediction of malignant ventricular arrhythmias is very challenging. The late gadolinium enhancement (LGE) dispersion mapping is a radiomics method for the quantification of tissue heterogeneity through the Global Dispersion Score (GDS). The aim of this study is the prognostic role of GDS in DCM patients. Methods or Background: In this multicentre study 510 consecutive patients with non-ischemic DCM were enrolled. All patients underwent cardiac magnetic resonance imaging. LGE images were retrospectively analysed by measurement of GDS. A combined endpoint of sudden cardiac death, cardiac arrest and appropriate implantable cardioverter-defibrillator intervention was considered. Results or Findings: Mean left ventricular ejection fraction (LVEF) was 35±11%. LVEF was >35% in 241 patients (47%). LGE was present in 225 patients (45%). Median extent of LGE was 12% of LV mass (interquartile range -IQR- 6-20%). Among patients with positive LGE, GDS was 0.14 (IQR 0.08-0.20). The whole population was divided in 3 groups: GDS=0, GDS>0 and ≤0.10 and GDS>0.10. During follow-up 81 patients had major events (8 SCD, 73 appropriate ICD interventions). At Kaplan-Meier analysis, patients with GDS>0.10 had worse prognosis than those with lower values of GDS (p<0.0001). At multivariate analysis, GDS>0.10 (HR 2.9, 95% CI 1.7-5, p=0.0002) was an independent predictor of events. Subgroup analysis confirmed the prognostic value of GDS regardless of LVEF > or ≤35% and LGE extent. Conclusion: GDS is a useful marker to identify DCM patients at higher risk for major arrhythmic events regardless LVEF and extent of LGE. Limitations: LGE dispersion mapping was evaluated with 2D approach. Funding for this study: Institutional funds of University of Pisa, Fondazione G. Monasterio, University of Trieste. Has your study been approved by an ethics committee? Yes Ethics committee - additional information: Ethical Committee of Pisa.