MYH14 and hypertrophic cardiomyopathy: Mavacamten is a cardiac-specific myosin inhibitor approved for the treatment of adults with symptomatic hypertrophic obstructive cardiomyopathy (HOCM).1 It has been developed to target the hyper-contractile phenotype, which is a crucial aspect of hypertrophic cardiomyopathy (HCM) pathophysiology.