[Observation of 2 families with idiopathic hypertrophic subaortic stenosis].

The authors describe five patients from two families with idiopathic hypertrophic subaortic stenosis, among them a brother and sister -- twins. Based on literature data and their experience, they stress the importance of the clinical and electromechanocardiographic criteria in the diagnosis of the family form of that disease, prior to the direct cardiac examination. The possible mechanisms in the genesis of predominantly local septum hypertrophia and left ventricle are discussed, an explanation being sought in the genetically conditioned changes of mitochondria and plentiful utilization of adenosine triphosphate by the defective myofibrils. Autosome mode of handing down with an incomplete penetration of the dominant gen is admitted. The differentitation of the family form of idiopathic hypertrophic subaortic stenosis is backed up as a separate nozological entiety bearing in mind another possible etiopathogenetic mechanism.