A cace of obstructive cardiomyopathy has been presented. A pressure gradient was evident across the outflow tract of both ventricles under resting condition. Angiocardiography showed marked hypertrophy of the interventricular septum which bulged into the right ventricle as well as into the left. Ventriculo-myotomy was carried out to relieve the obstruction. Special attention was directed to the ultrastructural findings of the resected myocardium, which showed dissociation of the intercalated disc. The condition offers addition-al support to the concept of "disease of the intercalated disc".