Immunoglobulin adsorption in patients with idiopathic dilated cardiomyopathy

Background-Idiopathic dilated cardiomyopathy (IDC) frequently is a progress ive disease without causative therapy options. Following the hypothesis tha t in certain patients autoantibodies against cardiac structures may induce, maintain, or promote the progression of the disease, we investigated wheth er the elimination of these autoantibodies through immunoadsorption would i mprove cardiac function. Methods and Results-This prospective case-control study included 34 patient s with IDC. Each patient presented with moderate to severe heart failure an d evidence of autoantibodies directed against beta(1)-adrenoceptors (beta(1 )-AABs), Seventeen patients received standard medical therapy (control grou p), whereas 17 were also treated with immunoadsorption (treatment group) to eliminate beta(1)-AABs. A 1-year follow-up included echocardiographic asse ssment of left ventricular ejection fraction and internal diameters, beta(1 )-AAB levels, and clinical status every 3 months. Within 1 year, the mean /- SD left ventricular ejection fraction rose from 22.3 +/- 3.3% to 37.9 +/ - 7.9% (P = 0.0001) in the treatment group, with a relative increase of 69. 9%, However, in the control group, no overall increase was seen (from 23.8 +/- 3.0% to 25.2 +/- 5.9%, P = 0.3154). Left ventricular diameter in diasto le decreased by 14.5% from 74.5 +/- 7.1 to 63.7 +/- 6.0 mm in the treatment group (P = 0.0001) and by 3.8% (P = 0.2342) in the control group. In the t reatment group, the NYHA functional rating improved after immunoadsorption (P = 0.0001). beta(1)-AABs did not increase anew. Conclusions-In IDC, the use of immunoadsorption is superior to the use of s tandard medical therapy. It significantly improves cardiac performance and clinical status.