Differential effects of β-adrenoreceptor antagonists on central and peripheral blood pressure at rest and during exercise

center dot At rest, beta-adrenoreceptor antagonists lower peripheral systolic blood pressure (SBP) but have less effect on central SBP. center dot Effects of beta-adrenoreceptor antagonists on central and peripheral blood pressure during exercise are unknown. WHAT THIS STUDY ADDS center dot This study shows that acute beta-blockade in healthy normotensive subjects markedly reduces peripheral SBP by similar to 20 mmHg during moderate exercise but has no significant effect on central SBP. center dot The differential effect of beta-blockade on central and systolic blood pressure is not completely explained by reduction in heart rate. Beta-blockade may blunt dilation of muscular arteries, influencing peripheral amplification during exercise. BACKGROUND Differential effects of beta-adrenoreceptor antagonists (beta-ARB) on central and peripheral blood pressure may relate to change in heart rate and/or vasodilator tone and thus be exaggerated during exercise. AIMS To examine acute effects of selective and nonselective beta-ARB on central and peripheral blood pressure, cardiac output and peripheral vascular resistance during exercise. METHODS Healthy volunteers (n = 20, 18 men, 19-54 years) received propranolol 80 mg, bisoprolol 20 mg, and placebo 1 h before bicycle ergometry (50, 75 and 100 W each for 3 min) in a randomized, cross-over study. Cardiac output was determined by pulmonary uptake of soluble and inert gas tracers (InnoCor, Innovision). Central systolic blood pressure (SBP) was determined from the late systolic shoulder of the digital artery pressure waveform (Finometer, Finopres). RESULTS At rest, both beta-ARB reduced brachial but not central SBP (compared with placebo). During exercise, beta-ARB reduced brachial SBP (reductions of 19.9 +/- 4.3 mmHg and 23.2 +/- 2.7 mmHg for propranolol and bisoprolol, respectively, at 100 W, each P < 0.0001) but not central SBP. The difference between peripheral and central SBP was reduced, relative to that during placebo, by 21.5 mmHg (95% confidence interval 8.8, 34.1) and 26.4 mmHg (18.1, 34.8) for propranolol and bisoprolol, respectively, at 100 W (each P < 0.01). There was no significant effect of beta-ARB on diastolic blood pressure or peripheral vascular resistance. CONCLUSIONS Despite reducing brachial blood pressure, acute beta-adrenoreceptor blockade in man at rest and during exercise does not reduce central blood pressure.