Danos et al. found that ifhl1 expression increased in hypertrophic obstructive cardiomyopathy (HCM) after Fhl1 alternative splicing, and HCM significantly deteriorated after Fhl1 ablation, including increased left ventricular hypertrophy, fibrosis and induced pathological remodelling of molecular markers. This evidence concerns the gene FHL1 and hypertrophic cardiomyopathy.