Background: Previous studies have shown that the sera of many patients with dilated cardiomyopathy (DCM) are positive for several antibodies directed against cardiac antigens. Anti-beta1-adrenergic receptor antibodies occur in 70% to 90% of DCM patients. These antibodies are extractable by immunoadsorption (IA). In an investigation of the functional significance of antibodies for hemodynamics, IA was performed throughout 5 consecutive days on nine patients with severe DCM who were on stable drug therapy.
Methods and results: Immunoglobulins were eliminated in nine patients with severe DCM (mean age, 43.5 years; range, 25 to 58 years; left ventricular ejection fraction, <25%). IA was performed over 5 consecutive days with an immunoadsorber for immunoglobulin. All patients were on stable medication, including ACE inhibitors, digitalis, and diuretics. All patients received beta-blockers. During therapy, hemodynamic parameters (mean+/-SD) were monitored with a Swan-Ganz thermodilution catheter. IA elicited a decrease of anti-beta1-adrenergic receptor antibodies from 6.4+/-1.3 to 1.0+/-0.5 relative units. During IA, cardiac output increased from 3.7+/-0.8 to 5.5+/-1.8 L/min, P<.01. Mean arterial pressure decreased from 76.0+/-9.9 to 65.0+/-11.2 mm Hg, P<.05; mean pulmonary arterial pressure, from 27.6+/-7.7 to 22.0+/-6.5 mm Hg, P<.05; left ventricular filling pressure, from 16.8+/-7.4 to 12.8+/-4.7 mm Hg, P<.05; and systemic vascular resistance, from 1465+/-332 to 949+/-351 dyne x s x cm(-5), P<.01.
Conclusions: In addition to conventional medical treatment, IA may be an additional therapeutic possibility for acute hemodynamic stabilization of patients with severe DCM.