While the m6A-dependent and YTHDC1-guided Titin pre-mRNA splicing produced a shorter and more rigid Titin isoform, N2B, cardiomyocyte-targeted conditional YTHDC1 knockout led to expression dominance of longer and less stiff N2BA isoform manifesting with DCM phenotype and ultimately HF.150. This evidence concerns the gene YTHDC1 and hydrops fetalis.