398 CARDIAC MAGNETIC RESONANCE PHENOTYPE AND GENOTYPE IN LEFT-SIDED CARDIOMYOPATHIES: CHARACTERIZATION AND CLINICAL OUTCOMES


 
 
 The combined prognostic role of cardiac magnetic resonance (CMR) and genotype in cardiomyopathies has not been fully investigated. The aim of this study was to identify specific genotype-CMR phenotype correlations in a well-characterized cohort of patients with a spectrum of left-sided cardiomyopathies spanning from arrhythmogenic (ACM) to dilated cardiomyopathy (DCM), and analyze patients’ outcome.
 
 
 
 One-hundred and seventy-four patients with DCM (127) and left sided ACM (47), who underwent a comprehensive evaluation including genetic testing and CMR imaging, were enrolled in this study. The phenotype was classified as DCM or ACM according to current consensus criteria. The primary outcome was a composite of sudden cardiac death/life-threatening ventricular arrhythmias (SCD/MVA). DCM patients showed more frequently pathogenic or likely pathogenic (P/LP) variants of non-arrhythmic genes (34% vs. 7%, p < 0.001), whereas ACM patients reported more frequently P/LP variants of arrhythmic genes (47% vs. 8%, p < 0.001) and non-ischemic free-wall LGE (30% vs. 10%, p = 0.002). After a median follow-up of 92 months (interquartile range 46 - 168), 39 patients (22%) reached the combined endpoint. Carrying a P/LP variant of arrhythmic genes (hazard ratio (HR) 2.2, 95% confidence interval (CI) 1.1 - 4.4, p = 0.024) along with presence of LGE (HR 4.5, 95% CI 1.99 - 11.5, p < 0.001) were independently associated with the study endpoint.
 
 
 
 In cohort of well-characterized left sided cardiomyopathies patients spanning from ACM to DCM, a P/LP variant of arrhythmic genes along with presence of LGE were independent predictors of SCD/MVA.
