A Four-Dimensional Volumetric Quantification of the Left Ventricle in Healthy Pregnant Women in the Third Trimester

Background: Hemodynamic load and heart structural remodeling rise during pregnancy because these changes are physiologically necessary. Adaptations in the mother's circulatory system may either initiate or aggravate the development of cardiovascular disease in the offspring. If the body is unable to adjust to these changes, it may develop heart conditions like cardiomyopathy. There is a lack of third-trimester echocardiographic data on left ventricular (LV) volume and function in healthy Iraqi women. To understand the cardiac alterations that occur during normal pregnancy, a precise tool that evaluates cardiac function is needed. In that regard, the four-dimensional echocardiography (4DE) technique has markedly improved the quality and accuracy of assessing the size and function of the left ventricle. Aim: The present study aimed to assess LV volume and function in the third trimester of a healthy pregnancy using 4DE and to compare the results of LV assessment using 4DE with those of LV assessment using conventional two-dimensional (2D) echocardiography. Methods: The study was conducted on 75 healthy pregnant women (the case group) and 75 non-pregnant women (the control group). The participants attended Al-Fortat Teaching Hospital from April 1, 2022, to May 30, 2023, and had 2D and 4D echocardiographic studies performed on them. Results: The LV end-diastolic volume (EDV), end-systolic volume (ESV), and cardiac output (CO) were significantly increased in the case group compared to the control group (90.87 ± 18.03 ml vs. 62.64 ± 14.11 ml, P<0.001; 35.59 ± 6.52 ml vs. 22.42 ± 5.82 ml, P<0.001; and 4.87 ± 1.27 vs. 3.35 ± 0.87 L/m, P<0.001, respectively). In contrast, the LV ejection fraction (LVEF) was significantly decreased in the pregnant group compared to the control group (60.37 ± 5.42 % vs. 64.04 ± 4.99 %, P<0.01). Additionally, the study showed significant differences in EDV, ESV, ejection fraction (EF%), and CO (P<0.001) between 2D and 4D echocardiography, according to the Bland Altman test. Conclusion: In healthy pregnant women in their third trimester, there is an increase in the indicators of preload (ventricular volume and CO) and a decrease in EF%. The 4DE provides detailed images and information about cardiac volumes and function, allowing for the early detection of any potential problems that may arise during pregnancy and thus improving the health outcomes of both the mother and the developing fetus.