Genetically-linked (AD) hypertrophy of cardiac muscle - can but does not always cause outflow obstruction
Up to 30% of patients will have no family history
Average age of diagnosis between 30-40 years of age
Diastolic heart failure
Abnormal LV function due to decreased compliance
Historically, obstructive forms known as:
Idiopathic<unk>  subaortic stenosis (IHSS)
Asymmetric septal hypertrophy (ASH)<unk>  obstructive cardiomyopathy (HOCM)
Yamaguchi syndrome, an atypical<unk> OM, in which only 1% are non-Japanese
Abnormal LV function due to decreased compliance
Idiopathic<unk>  subaortic stenosis (IHSS)
Asymmetric septal hypertrophy (ASH)<unk>  obstructive cardiomyopathy (HOCM)
Hypertrophic cardiomyopathy
Seizure
Restrictive cardiomyopathy
Breath-holding spell
Dilated cardiomyopathy
Hyperventilation syndrome
Mitral valve prolapse
Pregnancy 