β-blockers, angiotensin II, and ACE inhibitors in patients with heart failure

Blood concentrations of angiotensin II are often raised in patients with heart failure, despite treatment with angiotensin-converting-enzyme (ACE) inhibitors. We compared concentrations of angiotensin II in two groups of matched patients, receiving ACE inhibitor therapy with or without concomitant administration of β-blockers. Concentrations of angiotensin II were lower in individuals taking β-blockers than in those who were not (geometric mean 1·1 [95% Cl 0·4–2·7] vs 15·5 [4·6−52·6] fmol/mL, 95% Cl for difference 3–59). Our findings indicate that a reduction in angiotensin II concentrations might contribute to the therapeutic benefits of β-blockade in heart failure, especially in patients who simultaneously receive ACE inhibitor treatment.