To evaluate whether TNF-α genotyping may assist in identifying a subset of patients who could potentially benefit from immunomodulatory therapy, we assessed the relationship between the G-308A polymorphism of the TNF-α gene and changes in left ventricular (LV) chamber dimensions and systolic function in patients with idiopathic dilated cardiomyopathy (IDC) before and six months after diuretic, digoxin and angiotensin-converting enzyme inhibitor (ACEI) therapy. Here, TNF is linked to idiopathic dilated cardiomyopathy.