 Participants will be healthy volunteers or subjects with the diagnosis of hypertrophic cardiomyopathy HCM. All patients will a undergo a one time; medical history, physical examination, questionnaires, sleep observation in hospital, blood and urine samples, ultrasound scan of the heart, paced breathing test, ultrasound of brachial artery in the arm, MRI of the heart 48 hour ECG Holter monitoring. Comparison between the normal volunteers and subjects with HCM will be made. 