HISTIOCYTOID CARDIOMYOPATHY - 3 NEW CASES AND A REVIEW OF THE LITERATURE

Histiocytoid cardiomyopathy (HC), a rare arrhythmogenic disorder, pres ents as difficult-to-control arrhythmias or sudden death in infants an d children, particularly girls. Three cases are described with autopsy findings. In two cases. yellow-tan nodules were grossly visible in th e myocardium; in the third case, no gross lesions were identified. Mic roscopic examination in all three cases revealed multiple, scattered c lusters of histiocytoid myocytes which on ultrastructural examination were filled with abnormal mitochondria, scattered lipid droplets, and scanty myofibrils. These pathologic findings are similar to those prev iously described. The pathogenesis of this entity remains controversia l. It was recently proposed that this disorder is X-linked dominant wi th the associated gene located in the region of Xp22.