 The investigators are trying to find out how common sleep apnea is in hypertrophic cardiomyopathy. The purpose of this study is to see if sleep apnea is common in hypertrophic cardiomyopathy and if its presence is associated with changes in the functioning of the body. The investigators want to determine if sleep apnea is associated with electrical disorders of the heart in patients with hypertrophic cardiomyopathy. 