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Updated: Oct 17, 2026

Biventricular Assessment of Cardiac Function and Pressure-Volume Loops by Closed-Chest Catheterization in Mice
Published on: June 15, 2020
Left ventricular function and autonomic nervous system balance during two different stages of the menstrual cycle
A J Fuenmayor1, L Ramírez, A M Fuenmayor
1Electrophysiology and Arrhythmia Section of the Cardiovascular Research Center and Department of Physiology, University of The Andes, Mérida, Venezuela. ajf@cantv.net
Abstract:
We studied the left ventricular function and cardiac autonomic nervous system balance variations during two different stages of the menstrual cycle. These two variables, as well as plasmatic estradiol and progesterone concentrations, were measured in a drug-free state in 20 women (29+/-6 year-old) with regular menstrual periods. A clinical evaluation, an echo-Doppler and a Valsalva manoeuvre were performed in all the patients on the third day of their menstrual cycle (follicular phase) and three days prior to their next menstrual cycle (luteinizing phase). When comparing the results obtained in these two phases, a statistically significant increase was put forward in plasmatic estradiol (50.6+/-24 vs. 127.3+/-52.8 pg/ml) and progesterone (0.37+/-0.42 vs. 11.92+/-10.8 ng/ml) concentrations, Valsalva index (1.55+/-0.22 vs. 1.67+/-0.33; P=0.044) and E/A mitral wave ratio (1.63+/-0.36 vs. 1.75+/-0.35, P=0.02). The right and left atrial volumes, left ventricular volumes and ejection fraction were similar in the two menstrual phases studied. We conclude that the autonomic nervous system balance and the left ventricular diastolic function suffer significant changes during the luteinizing phase of the menstrual cycle in normal women.
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