[Serum autoantibodies against the cardiac beta(1)-adrenergic receptor in patients with chronic heart failure: clinical characteristics and response to carvedilol].

Objective: To detect the serum autoantibodies against the cardiac beta(1)-adrenergic receptor and observe the clinical characteristics and response to carvedilol use in patients with chronic heart failure (CHF).

Methods: Cardiac function was examined by echocardiography and levels of autoantibodies against cardiac beta(1)-adrenergic receptor were detected in 65 patients with CHF by means of enzyme linked immune assay. Carvedilol was added on ACEI, diuretics and digitalis regimen for a target dose of 50 mg/d. All patients were followed up for 6 months.

Results: Autoantibodies against cardiac beta(1)-adrenergic receptor were detected in 30 patients (group 1) and not detected in the remaining 35 patients (group 2). The achieved target dose of carvedilol was significantly higher in group 1 than that in group 2 [(36.25 +/- 14.31) mg/d vs. (25.97 +/- 8.83) mg/d, P < 0.01]. Heart rate was significantly higher in group 1 compared to group 2 [(94.19 +/- 14.46) beats/min vs. (86.56 +/- 15.88) beats/min, P < 0.05] before treatment and heart rate and blood pressure of both groups decreased significantly (P < 0.01) and there was no significant difference between two group (P > 0.05) after 6 months treatment. LVEDD and LVESD were significantly larger while LVEF significantly lower in group 1 patients than those in group 2 patients (all P < 0.05) before treatment and LVEDD and LVESD decreased and LVEF increased significantly in both groups (all P < 0.01 vs. before treatment) and there was on significant difference in LVEDD, LVESD and LVEF between two groups (all P > 0.05) post 6 months treatment. Moreover, average titer of autoantibodies against the cardiac beta(1)-adrenergic receptors significantly decreased after 6 months treatment (1:119.35 vs. 1:72.21, P < 0.01).

Conclusion: The detection of autoantibodies against the cardiac beta(1)-adrenergic receptors is related to severer cardiac dysfunction and autoantibodies title decrease was found with improved cardiac function after standard therapy (ACEI, digitalis, betablocker) in patients with CHF.