Comparison of non-invasive cardiac output across the three trimesters of gestation in preeclamptic versus normotensive pregnancies

Abstract Objective To longitudinally track noninvasive hemodynamic parameters across different gestational ages in pregnancies with and without preeclampsia (PE) using the PeriCare noninvasive hemodynamic monitoring system. Methods A prospective cohort of 635 pregnant women who underwent routine prenatal care at Chongqing Maternal and Child Health Hospital between October 2023 and October 2024 was enrolled. Among them, 581 were classified into the normal pregnancy group and 54 into the PE group. The PeriCare noninvasive hemodynamic monitoring system was used to measure gestational age-related changes in cardiac output (CO), cardiac index (CI), stroke volume (SV), SV index (SVI), thoracic fluid content (TFC), systemic vascular resistance (SVR), SVR index (SVRI), and mean arterial pressure (MAP). Statistical analyses were performed to compare baseline characteristics and longitudinal hemodynamic changes between the two groups. Results Baseline characteristics, including maternal age, height, BMI at first assessment and at delivery, and neonatal birth weight, did not differ significantly between the two groups ( P > 0.05). By the second and third trimesters, women in the PE group exhibited significantly lower CO, CI, SV, and SVI, along with significantly higher TFC, SVR, SVRI, and MAP compared with the normal pregnancy group ( P < 0.05). Longitudinal analysis showed that from the second trimester onward, MAP, SVR, and SVRI continuously increased in the PE group but declined physiologically in normal pregnancies. From the first to the second trimester, the PE group also demonstrated significantly lower rates of increase in CO and CI, and higher rates of increase in TFC, as well as greater rates of decline in SV and SVI relative to the normal pregnancy group ( P < 0.05). Conclusions Dynamic hemodynamic monitoring using the PeriCare system revealed a distinctly altered hemodynamic trajectory in women who developed PE, with significant divergence emerging during the second trimester. Enhanced noninvasive hemodynamic surveillance during this critical period identifies distinct hemodynamic trajectories that may represent potential targets for future early predictive modeling of PE, pending validation of their predictive performance. The PeriCare system represents a feasible tool for longitudinal monitoring. However, future studies are required to establish its definitive diagnostic utility.