In this narrative review, we focus on cardiomyopathy-associated genotypes consistently linked to high arrhythmic risk-LMNA, truncating variants in FLNC, RBM20, PLN p.Arg14del, and desmosomal genes-and examine their molecular mechanisms, phenotypic trajectories, and arrhythmogenic profiles. This evidence concerns the gene RBM20 and cardiomyopathy.