Long-term effect of atenolol on ejection fraction, symptoms, and exercise variables in patients with advanced left...

We recently reported a beneficial clinical effect of atenolol, a beta(1) selective adrenergic antagonist, in 100 ambulatory heart failure patients with low left ventricular ejection fraction (LVEF,

We included 43 patients (23 receiving atenolol, 20 receiving placebo) who had similar entry characteristics. We evaluated LVEF once a year and evaluated workload, pVO(2), and NYHA class before and after 6, 12, and 24 months. Repeated measures of analysis of variance were used for comparison of serial measurements. After 2 years, both atenolol (18% +/- 5% vs 36% +/- 18%, p < 0.05) and placebo (18% +/- 5% vs 23% +/- 5%, p < 0.05) increased LVEF, with a more pronounced effect of atenolol (p = 0.02), which also changed NYHA class distribution more favorably over time (p < 0.05). Workload and peak Vo(2) increased after atenolol (110 +/- 47 vs 140 +/- 48 watts, p < 0.05, and 18 +/- 5 vs 21 +/- 5 ml/kg/min, p < 0.05) but not after placebo (100 +/- 35 vs 110 +/- 38 watts, p < 0.05, between groups and 17 +/- 4 vs 19 +/- 7 ml/kg/min, not significant, between groups).

In patients with advanced heart failure who tolerate long-term atenolol vs placebo treatment added to high-dose enalapril for 2 years without cardiac events, systolic left ventricular function is markedly improved. These patients experience greater relief of symptoms and increased exercise tolerance.