Cardiovascular Adaptation in Normal Pregnancy With 2D and 3D Echocardiography, Speckle Tracking, and Radial Artery Tonometry

Background: Comprehensive cardiovascular assessment in normal pregnancy using advanced techniques has limited data.

Objectives: The aim of the study was to evaluate cardiovascular changes in normal pregnancy using two-dimensional/three-dimensional (3D) echo and applanation tonometry in healthy pregnant women.

Methods: Two-dimensional/Doppler, speckle tracking strain, 3D echocardiography, and vascular compliance by applanation tonometry were performed during the first, second, and third trimesters and postpartum.

Results: There were 45 healthy women (96% Hispanic) included. The heart rate increased in all trimesters vs postpartum (70.538 ± 9.208 beats/min, 74.878 ± 8.094 beats/min, 74.107 ± 9.231 beats/min vs 61.613 ± 9.790 beats/min, P < 0.001). A 3D left ventricular (LV) end systolic volume (34.583 ± 6.946 mL, 39.405 ± 7.345 mL, 45.994 ± 15.180 mL, 36.077 ± 7.116 mL), LV end diastolic volume (83.672 ± 14.022 mL, 91.512 ± 14.602 mL, 97.581 ± 19.864 mL, 85.163 ± 13.960 mL), right ventricular (RV) end systolic volume (30.690 ± 6.194 mL, 35.390 ± 7.345 mL, 40.929 ± 15.178 mL, 30.740 ± 6.911 mL), RV end diastolic volume (77.074 ± 14.875 mL, 86.871 ± 16.783 mL, 92.926 ± 18.083 mL, 78.267 ± 15.07 mL), and cardiac output increased (P < 0.01 for all) in the 2nd and 3rd trimester. LV longitudinal strain rate (SR) (-1.242 ± 0.350, -1.194 ± 0.181, -1.231 ± 0.263 vs -1.068 ± 0.218, P < 0.05) increased in all trimesters, RV longitudinal SR (-1.612 ± 0.314, -1.540 ± 0.284, -1.281 ± 0.748 vs -1.361 ± 0.306) in the 1st and 2nd trimester, P < 0.01), left atrial SR (1.735 ± 0.461, 1.687 ± 0.540, 1.588 ± 0.0.526 vs 1.414 ± 0.325), and right atrial SR (2.389 ± 0.582, 2.264 ± 0.741, 2.241 ± 0.793 vs 1.861 ± 0.600) in all trimesters, (P < 0.05). Left atrial volume increased in 2nd and 3rd trimesters, left atrial contraction velocity in 3rd trimester (P < 0.05), and pulmonary vein systolic filling velocity throughout pregnancy (P < 0.001). E/e' ratio did not change and LV ejection duration increased. Systolic augmentation of central aortic pressure decreased throughout.

Conclusions: Increased contractility of all four cardiac chambers, LV ejection-duration, and reduced LV afterload provide efficient cardiovascular adaptation despite increased chamber volumes and heart rate during normal pregnancy.