The annual incidence of sudden cardiac death in young athletes is approximately 
1 in 200,000. The most common causes include hypertrophic cardiomyopathy and 
arrhythmogenic right ventricular dysplasia/cardiomyopathy. These genetic 
disorders typically manifest in the second decade of life and have the potential 
for sudden death as the first symptom. Medical care providers must be aware of 
these disease entities when evaluating patients with seizures, syncope, and/or 
palpitations. The purpose of this article is to describe their genetics, 
clinical presentation, and diagnosis.