Structural and functional changes in maternal left ventricle during pregnancy: a three-dimensional speckle-tracking echocardiography study

Abstract

Background: Pregnancy represents a physiological adaptation to the transient load changes of maternal heart. This study aimed to investigate maternal left ventricle (LV) performance during normal pregnancy by three-dimensional speckle-tracking echocardiography (3D STE) parameters considering LV loading and shape.

Methods: Sequential two-dimensional echocardiography (2DE) and 3D STE were performed on 68 women during each pregnancy trimester and 6 to 9 weeks after delivery, while thirty age-matched, healthy, nonpregnant women served as controls. Global longitudinal strain (GLS), global circumferential strain (GCS), global area strain (GAS) and global radial strain (GRS) were measured.

Results: Increased cardiac index and progressive eccentric hypertrophy was detected, which subsequently recovered postpartum. In late pregnancy, GLS, GCS, GAS and GRS significantly decreased (P < 0.05) accompanied by a slight reduction of LV ejection fraction (EF) (P < 0.05), and these values returned postpartum to baseline level. All 3D strain indices correlated well with gestation age (P < 0.01), while compared to other components, GAS exhibited the strongest association with 3D EF (r = 0.549) and sphericity index (r = 0.328), and was the only parameter that correlated well with LV mass index (r = 0.22).

Conclusions: This study gives normal ranges of 3D STE indices in pregnancy. 3D STE demonstrated modified myocardial deformation and changes in maternal LV structure and function during the gestation period.

Figure 1

Automated detection of the endocardium and epicardial border throughout the whole cardiac cycle. Consequently end-diastolic volume (EDV), end-systolic volume (ESV), ejection fraction (EF), stroke volume (SV), cardiac output (CO), sphericity index(Spl) and LV mass either at end-diastole (EDMass) or at end-systole (ESMass) were automatically calculated.

Figure 2

Both strain curves and a color-coded 17-segment bull’s eye plot were presented. Color lines indicate regional strain; white dotted line means global (average) strain. Values of longitudinal strain, circumferential strain, and area strain are negative (sign -), whereas values of radial strain are positive (sign +). GAS indicates global area strain; GCS, global circumferential strain; GLS, global longitudinal strain; GRS, global radial strain.

Figure 3

Evolution of maternal LV morphology and function during pregnancy and postpartum by 3D STE. Data are presented as mean ± SD. LVEDV indicates left ventricular end-diastolic volume; LVESV, left ventricular end-systolic volume; LVEDVi, left ventricular end-diastolic volume index; EF, ejection fraction; CI, cardiac index; SVI, stroke volume index; LVMi, left ventricular mass index; LA index, left atrial volume index; *P < 0.05 vs. Controls; †P < 0.05 vs. Trimester 1; ‡P < 0.05 vs. Trimester 3; §P < 0.05 vs. Postpartum.

Figure 4

Assessment of myocardial deformation during pregnancy and postpartum by 3D STE. Data are presented as mean ± SD. Note that GLS, GCS, GRS and GAS decreased in Trimester 3, while returned in postpartum. GLS indicates global longitudinal strain; GCS, global circumferential strain; GAS, global area strain; GRS, global radial strain. *P < 0.05 vs. Controls; †P < 0.05 vs. Trimester 1; ‡P < 0.05 vs. Trimester 3; §P < 0.05 vs. Postpartum.