Cardiac involvement is frequent in myotonic dystrophy type 2 (DM2) with dilated 
cardiomyopathy and severe arrhythmias having been reported. Left ventricular 
non-compaction is a cardiomyopathy often associated with neuromuscular 
disorders. We report the case of a 61-year-old man with DM2 treated for 5 years 
for a suspected dilated cardiomyopathy. Echocardiography showed left ventricular 
non-compaction typical pattern, with prominent apical trabeculations and 
intertrabecular spaces perfused from ventricular cavity. MRI confirmed the 
diagnosis. Physicians should be aware of the risk of severe cardiac 
complications in DM2 patients. Left ventricular non-compaction diagnosis is 
often overlooked. Neurological examination should be performed in all patients 
with left ventricular non-compaction.