EFEMP2 and dilated cardiomyopathy: To establish if the exaggerated dilated cardiomyopathy triggered by TAC in fibulin-4+/R mice with reduced gene dosage originates primarily from abnormalities within the extracellular matrix, we investigated the presence of fibulin-4 protein and elastin expression in the myocardium of fibulin-4+/+ and fibulin-4+/R animals.