Age at diagnosis with hypertrophic cardiomyopathy. (A) Distribution of age at diagnosis in patients with hypertrophic cardiomyopathy (n = 7677). There are three peaks when hypertrophic cardiomyopathy is diagnosed throughout the lifespan: infancy (the 1st year of life), adolescence (teenage years), and middle adulthood (∼50 years of age). (B) Distribution of age at diagnosis in patients with genetic testing (n = 4746), stratified by sarcomeric variant status. Sarcomeric hypertrophic cardiomyopathy (teal) presents 9.3 years earlier than non-sarcomeric hypertrophic cardiomyopathy (pink). Sarcomeric hypertrophic cardiomyopathy is more common prior to age 50, and non-sarcomeric hypertrophic cardiomyopathy is more common thereafter.