JAMA : the journal of the American Medical Association
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Chronic heart failure is the leading cause of hospital admissions in patients older than 65 years. Heart failure due to systolic dysfunction is accompanied by activation of the sympathetic nervous system that contributes to progressive symptoms and an increased risk of death. While several clinical trials have suggested that antagonizing this sympathetic activation with beta-blocking agents may provide clinical benefit, no clear consensus exists regarding use of beta-blockers for congestive heart failure. Therefore, we review the pathophysiology of the sympathetic nervous system as a basis for examining these clinical trials in order to understand the rationale for beta-blockade as a treatment for heart failure. ⋯ Sympathetic nervous system activation in patients with chronic heart failure is a major contributor to the severity of disease as well as its progression over time. Antagonism of its effects, via beta-blocker therapy, appears overall to improve both quality of life and survival. However, its place as a cornerstone in the therapy of this disease depends on the results of large-scale, randomized, placebo-controlled trials.
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To provide physicians and other transfusion medicine professionals with a current consensus on infectious disease testing for blood transfusions. ⋯ The serum alanine aminotransferase test should be discontinued as a surrogate marker for blood donors likely to transmit posttransfusion non-A, non-B hepatitis infection since specific hepatitis C antibody testing has eliminated more than 85% of these cases. Antibody to hepatitis B core antigen testing should continue as it may prevent some cases of posttransfusion hepatitis B; it may also act as a surrogate marker for human immunodeficiency virus (HIV) infection in donors and may prevent a small number of cases of transfusion-transmitted HIV infection. Syphilis testing should continue until adequate data can determine its effect on the rarity of transfusion-transmitted syphilis. Vigilant public health surveillance is critical in responding to emerging infectious disease threats to the blood supply.