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Published on: August 13, 2019
Influence of endogenous oestrogens on QT interval duration
Jean-Sébastien Hulot1, Jean-Louis Démolis, Rachel Rivière
1Division of Clinical Pharmacology, Saint-Antoine University Hospital, Paris, France.
European Heart Journal
|September 23, 2003
Summary
Physiological variations in oestradiol levels during the menstrual cycle do not significantly alter QT interval duration in healthy women. This study found no difference in cardiac repolarization despite wide oestradiol fluctuations.
Area of Science:
- Cardiology
- Endocrinology
- Reproductive Physiology
Background:
- Women exhibit longer QT intervals and higher torsades de pointes incidence than men.
- Oestrogens are hypothesized to influence cardiac repolarization duration.
Purpose of the Study:
- To investigate the effect of physiological oestradiol (E2) concentrations on ventricular repolarization.
- To determine if oestradiol levels during the menstrual cycle impact QT interval duration.
Main Methods:
- Studied 21 healthy women aged 18-35 years with regular menstrual cycles.
- Measured QT interval duration during low (menses) and high (pre-ovulatory) oestradiol phases.
- Utilized heart rate-independent QT assessment and monoexponential nonlinear curve fitting for QT-RR relation.
Main Results:
- No significant difference in QT(1000 ms) interval duration was found between peak (750+/-277 pmol/l) and nadir (105+/-34 pmol/l) oestradiol levels.
- QT(1000 ms) values were 382.1+/-18.4 ms at peak and 382.2+/-19.4 ms at nadir oestradiol (P=0.98).
Conclusions:
- Physiological variations in oestradiol levels within the menstrual cycle do not significantly alter QT interval duration.
- The study suggests oestradiol's role in cardiac repolarization may not be significant within the physiological range observed.
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