title: The effects of acute beta-adrenergic blockade on aortic wave reflection in postmenopausal women.
abstract: BACKGROUND Acute beta-adrenergic blockade increases aortic-wave reflection in young women. However, it is not known whether this effect extends to postmenopausal women. We therefore examined the effect of systemic beta-adrenergic blockade on aortic wave reflection in 14 postmenopausal women with a mean age of 58±2 years. METHODS Aortic pressure waveforms were synthesized noninvasively from high-fidelity radial pressure waveforms obtained through applanation tonometry before and during systemic beta-blockade with propranolol given in a bolus dose of 0.25mg/kg, followed by a continuous infusion at 0.004mg/kg/min. To further examine the effects of acute beta-blockade on aortic-wave reflection in postmenopausal women, we compared the changes in hemodynamics and indices of aortic-wave reflection with published data from a previous study with a protocol identical to that in the present study but which involved young women. RESULTS Acute beta-blockade increased the aortic augmentation index (AIx) in postmenopausal women (32±2% vs. 35±2%, P < 0.01). However, AIx adjusted for a heart rate of 75 bpm (AIx75) was unchanged (25±2% vs. 24±2%, P > 0.05). The changes in AIx, AIx75, and the amplitude of reflected waves (augmented aortic pressure) during beta-blockade were all substantially smaller in postmenopausal women than in their younger counterparts (P < 0.05). Conclusions As compared with those in our previously published study involving young women, indices of aortic-wave reflection were significantly less affected by acute systemic beta-adrenergic blockade in the postmenopausal women in the present study. Taken together, our data suggest that the negative effects (i.e. increased aortic wave reflection) of nonselective beta-adrenergic blockade are less pronounced in postmenopausal than in young women.
authors: Department of Anesthesiology, Mayo Clinic, Rochester, MN, USA. casey.darren@mayo.edu
authors: Darren P
authors: DP
authors: Casey
authors: Timothy B
authors: TB
authors: Curry
authors: Nisha
authors: N
authors: Charkoudian
authors: Michael J
authors: MJ
authors: Joyner
authors: Emma C
authors: EC
authors: Hart
mesh_terms: D000319:Adrenergic beta-Antagonists / Q000627:therapeutic use*; D001011:Aorta / Q000503:physiopathology*; D001794:Blood Pressure / Q000187:drug effects*; D005260:Female; D006801:Humans; D008875:Middle Aged; D017698:Postmenopause; D011433:Propranolol / Q000627:therapeutic use*; D063177:Pulse Wave Analysis; D059289:Vascular Stiffness / Q000187:drug effects*
chemical_list: D000319:Adrenergic beta-Antagonists; D011433:Propranolol