The Effects of Estrogen and Hormone Replacement Therapy on Aortic Stiffness

Objective: The main objective of this study was to investigate the effects of estrogen replacement therapy (ERT) and hormone replacement therapy (HRT) on aortic stiffness. Methods: The study groups were composed of postmenopausal women who were first examined in a gynecology clinic and thought to be suitable candidates for hormonal therapy. Group I was composed of 20 naturally menopausal women who were receiving 2 mg estradiol hemihidrate+noretisteron acetate, while group II consisted of 22 surgically menopausal women who received 2 mg estradiol hemihidrate. Each group was evaluated in respect to aortic elasticity properties before and after 12 weeks of hormonal therapy. Ascending aorta diameters were measured on the M-mode tracing at a level 3 cm above the aortic valve. The systolic diameter was measured at the maximal anterior motion of the aorta, whereas the diastolic diameter was measured at the peak of the QRS complex on the simultaneously recorded electrocardiogram. The right brachial artery systolic and diastolic pressures were obtained immediately before and after the echocardiographic study using conventional sphygmomanometry. Aortic strain and distensibility were calculated by using ascending aorta diameters and blood pressure measurements. Results: There were significant decreases for heart rate (85±13 vs 79±12 bpm, p=0.015), and beta index (5.2±2.5 vs 3.2±2.2, p=0.001) with ERT. Distensibility (5.2±3.75 vs 6.1±4 cm2.dyn-1.10-3, p=0.036) was increased by this therapy. HRT was observed to reduce heart rate (79±12 vs. 75±12 bpm, p=0.026) and improve aortic elasticity properties (for strain 10.7±4.7 vs. 12.8±7.6 %, for beta index 4.9±2.1 vs. 3.3±2.4 and for distensibility 4.6±2.1 vs. 5.6 ±4.1 cm2.dyn-1.10-3). Conclusion: Both ERT and HRT exerts improvement on aortic elasticity properties while progesterone has no adverse effect on thisi improvement.