Introduction: Uniform presentig features (dilatation and impaired systolic function) fail to reflect the true underlying causes. The pathogenic factor may be meta-bolic, infectious, ischemic, toxic or hereditary. The primary cause of sporadic or hereditary dilated cardiomiopathy in children rests unknown in over 70% of cases; the cascade of molecular and cellular events leading to heart failure remains poorly understood. The medicati-on has limited impact on prognosis, at least 1/3 of pati-ents will dye or have cardiac transplantation. Five cases with ultrasound diagnosis are presented, four having an underlying cause identified (genetic, structural or metabolic), the fifth remaining idiopathic.

Methods: All cases are deeply and assiduously inves-tigated for structural and mainly coronary abnormalities, non-evident rithm troubles, metabolic screening, familial history, infectious or immune causes.

Results: First case has a palmo-plantar keratosis and wooly hair (desmoplakine exxon 24 heterozigote mutation); cardiomyopathy became evident by exercise in-tolerance and is waiting for transplant, under maximal medication. The second case had left coronary abnormal pulmonary origin, the surgical repositionning le-ading to healing. The third case was operated for te-tralogy of Fallot and then considered for cardiac trans-plant; diagnosis of an atrial flutter and radiofrequency ablation solved the case. The fourth case was diagnosed with low plasma level of carnitine, lifelong substitution therapy maintaing normal life. The fifth case rests (yet?) cryptogenic, waiting for transplant.

Conclusions: The life-threatening impairment of car-diac function should not discourage the estensive re-search of the underlying cause in every single case of dilated cardiomyopahy, the precise diagnosis and cor-rect choice of therapy can lead to complete healing or long-term recover of cardiac function.