Immunoadsorption in idiopathic dilated cardiomyopathy, a 3-year follow-up

Recent studies have shown that immunoadsorption (IA) leads to improvements in left ventricular function and in functional status in selected patients with idiopathic dilated cardiomyopathy (DCM) and circulating autoantibodiesautoantibod. Most of the few studies dealing with this topic describe only short-term results. The aim of this study was to ascertain the prolonged effects of IA over a period of 3 years.

Our study included nine patients with circulating beta1-adrenoreceptor antibodies who suffered from idiopathic DCM (left ventricular ejection fraction <30%). IA was performed using an adsorber against immunoglobulins (Ig Therasorb, Baxter). During therapy and after 3 months, hemodynamic parameters were monitored using a Swan-Ganz thermodilution catheter. All patients were monitored under clinical and echographical examinations over a period of at least 3 years.

During IA hemodynamic measurements show increases in both cardiac and stroke volume index (from 2.0 (S.E.M. 0.16) to 3.0 (S.E.M. 0.32) l min(-1) m(-2), and from 26.1 (S.E.M. 2.63) to 38.9 (S.E.M. 3.56) ml/m2, respectively). Hemodynamic stabilization was observed after the following 3 months (CI 2.6 (S.E.M. 0.14) l min(-1) m(-2), SVI 37.9 (S.E.M. 2.14) ml/m2). After 36 months five patients were still alive. Antibody titers increased in patients who deteriorated. The five patients who are still alive show an increase in left ventricular ejection fraction and no significant increase in antibody titers.

Immunoadsorption may improve short-term hemodynamics as well as long-term follow-up of patients with severe idiopathic dilated cardiomyopathy. Increase in antibody titers is accompanied by deterioration of cardiovascular function.