Hypertrophic cardiomyopathy is a common inherited cardiovascular disease present 
in one in 500 of the general population. It is caused by more than 1400 
mutations in 11 or more genes encoding proteins of the cardiac sarcomere. 
Although hypertrophic cardiomyopathy is the most frequent cause of sudden death 
in young people (including trained athletes), and can lead to functional 
disability from heart failure and stroke, the majority of affected individuals 
probably remain undiagnosed and many do not experience greatly reduced life 
expectancy or substantial symptoms. Clinical diagnosis is based on otherwise 
unexplained left-ventricular hypertrophy identified by echocardiography or 
cardiovascular MRI. While presenting with a heterogeneous clinical profile and 
complex pathophysiology, effective treatment strategies are available, including 
implantable defibrillators to prevent sudden death, drugs and surgical myectomy 
(or, alternatively, alcohol septal ablation) for relief of outflow obstruction 
and symptoms of heart failure, and pharmacological strategies (and possibly 
radiofrequency ablation) to control atrial fibrillation and prevent embolic 
stroke. A subgroup of patients with genetic mutations but without 
left-ventricular hypertrophy has emerged, with unresolved natural history. Now, 
after more than 50 years, hypertrophic cardiomyopathy has been transformed from 
a rare and largely untreatable disorder to a common genetic disease with 
management strategies that permit realistic aspirations for restored quality of 
life and advanced longevity.