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Updated: May 23, 2026
06:34
Evaluation of Left Ventricular Structure and Function using 3D Echocardiography
Published on: October 28, 2020
Frequency-dependent left ventricular performance in women and men.
Rodrigo V Wainstein1, Zion Sasson, Susanna Mak
1The Harold & Esther Mecklinger Family and Posluns Family Cardiac Catheterization Research Laboratory, Mount Sinai Hospital, University of Toronto, Ontario, Canada.
Summary
Older women show greater left ventricular (LV) contractility responses to heart rate changes than men. Despite this, their cardiac output rises less, and external stroke work falls more, indicating sex differences in LV mechanical performance.
Area of Science:
- Cardiology
- Human Physiology
- Sex Differences in Medicine
Background:
- Sex influences left ventricular (LV) structure and function in healthy individuals.
- Aging affects cardiovascular physiology in a sex-specific manner.
- Understanding sex-based differences in cardiac response is crucial for personalized medicine.
Purpose of the Study:
- To investigate sex differences in the dynamic response of the LV to heart rate (HR) changes.
- To compare the force-interval relationships of the LV between postmenopausal women and age-matched men.
- To elucidate the impact of HR variations on LV mechanical performance in older adults.
Main Methods:
- Cardiac catheterization was used to study force-interval relationships in eight postmenopausal women and eight men.
- Right atrial (RA) pacing controlled HR, while LV +dP/dt(max) and volume were measured.
- LV pressure-volume relationships were analyzed using a time-varying elastance model; external stroke work was calculated.
Main Results:
- The slope of the relationship between HR and LV +dP/dt(max) was significantly steeper in women (11.8 ± 4.0) compared to men (6.1 ± 4.1).
- Women exhibited greater increases in LV contractility, even after normalization for LV end-diastolic volume (LVVed) or by measuring end-systolic elastance.
- LVVed and stroke volume decreased more in women, leading to a lesser rise in cardiac output and a steeper fall in external stroke work despite enhanced contractility.
Conclusions:
- Postmenopausal women demonstrate greater inotropic responses to incremental RA pacing compared to men.
- These enhanced contractility responses in women are accompanied by a steeper decline in external stroke work.
- Sexual dimorphism exists in the determinants of LV mechanical performance in older adults.
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