Vascular dysfunction in idiopathic dilated cardiomyopathy.

Idiopathic dilated cardiomyopathy (IDCM) is defined as myocardial dilatation and dysfunction in the absence of overt coronary heart disease. Myocardial injury and genetic or environmental factors can lead to the development of IDCM, which was historically characterized by marked abnormalities in the function and integrity of cardiomyocytes. However, cardiac endothelial dysfunction has also been shown to be associated with progression and poor prognosis of IDCM. Moreover, marked vascular derangements and impaired vasculogenic and angiogenic responses have been reported in patients with IDCM. On the basis of these data we re-examine IDCM pathophysiology as a downstream complication of vascular derangements that contribute to myocyte damage. Animal models closely resembling the marked vascular alterations found in patients with IDCM will be of paramount importance for further enhancing our comprehension of disease progression and for testing new drugs and stem-cell or gene-based therapies.