Anthropometrics and Thoracic Geometry as Determinants of Myocardial Strain During Pregnancy: Beyond Hemodynamics

Pregnancy is characterized by profound cardiovascular remodeling aimed at meeting the metabolic demands of the mother and the developing fetus. Recent longitudinal studies have reported a progressive reduction in left ventricular global longitudinal strain (LV-GLS) and right ventricular free-wall longitudinal strain during normal pregnancy, despite preservation of conventional indices of systolic function. While these changes have traditionally been attributed to physiological hemodynamic adaptations, the potential influence of anthropometric and anatomical factors has received less attention. In this commentary, we discuss the possible role of thoracic geometry and body morphology in modulating myocardial deformation measurements obtained by speckle-tracking echocardiography during pregnancy. Physiological changes such as diaphragmatic elevation, altered thoracic configuration, and increased intrathoracic pressure may influence ventricular mechanics as well as the technical performance of strain analysis algorithms. In addition, individual variations in chest wall conformation, including a reduced anteroposterior thoracic diameter and an elevated modified Haller index, may contribute to the variability of strain values observed among pregnant women. Recognizing the interaction between cardiac mechanics and thoracic geometry may therefore improve the interpretation of myocardial strain parameters and help avoid misclassification of physiological adaptations as myocardial dysfunction.