Familial hypertrophic cardiomyopathy with unusual involvement of the right ventricle

4 cases of familial hypertrophic cardiomyopathy are reported. In all of them, the onset of symptoms occurred before the 8th mth of life, and were characterized by severe right cardiac failure. In 3 cases the catheterization revealed significant decrease in right ventricular compliance and severe reduction of its cavity. The pathological studies were consistent with hypertrophic cardiomyopathy with predominant involvement of the right ventricle. The pedigree disclosed a Mendelian autosomal recessive type of inheritance.