A two and a half year old child was admitted to hospital with peripher
al cyanosis. Echocardiography revealed severe dilated cardiomyopathy a
ffecting both ventricles with abnormally hypertrophied and irregular m
yocardial walls. The pulmonary hypertension was suprasystemic with rai
sed pulmonary resistances. The magnetic resonance imaging and angiogra
phy confirmed the diagnosis of persistence of spongy myocardium. This
is a rare abnormality due to the persistence of embryonic myocardium w
ith a network of trabeculations and intertrabecular spaces as usually
observed during echocardiography. This case is noteworthy because of t
he biventricular involvement and the absence of associated congential
cardiac malformation. The prognosis is characterised by a high risk of
severe cardiovascular complications.