BENEFICIAL-EFFECTS OF METOPROLOL TREATMENT IN CONGESTIVE-HEART-FAILURE - REVERSAL OF SYMPATHETIC-INDUCED ALTERATIONS OF IMMUNOLOGICAL FUNCTION

Background Little information is available to explain why beta-blocker s are beneficial in certain patients with congestive heart failure (CH F). Since catecholamines alter immune function, we asked whether beta- blocker treatment leads to enhancement of immune function. Methods and Results Fifteen patients with New York Heart Association class III-IV CHF secondary to dilated cardiomyopathy were titrated to a minimum do se of metoprolol 25 mg BID on a background therapy of digoxin, diureti c, and angiotensin-converting enzyme inhibitors. Cardiac and immunolog ic studies were done before and 6 months to 1 year after treatment. Wh ile these patients served as their own controls, an additional populat ion of patients with heart failure was followed for a similar time per iod on traditional medications. A panel of seven delayed hypersensitiv ity skin tests were placed at 6- to 12-month intervals on the patient' s forearm. Seventy percent of all CHF patients were anergic (unable to respond to more than 1 antigen). The 30% who could respond averaged 2 .2 antigens. After treatment with metoprolol, only 20% remained anergi c (P<.001). The 80% of responders averaged 4.2 antigens (P<.001). Addi tionally, patients treated with metoprolol had an increased percentage of T cells, natural killer cells, and increased interleukin-2 recepto r density upon stimulation with concanavalin A, These changes correlat ed to increases in ejection fraction. Patients not treated with metopr olol remained anergic and had no beneficial immunologic changes. Concl usions It appears that patients with dilated cardiomyopathy who are tr eated with metoprolol have enhancement of cell-mediated immunity and i mprovement of T-cell function; these improvements are correlated to im provement in ejection fraction.