The implication of pericardial effusion in the third trimester for preeclampsia and heart failure in high-risk pregnant women.

Background: With the growing number of high-risk pregnant women, echocardiography frequently reveals pericardial effusion (PE). However, the clinical implications of PE are unknown.

Method: We analyzed a cohort of 406 high-risk pregnant women who underwent echocardiography in the third trimester between November 2019 and December 2022. The association between PE and clinical outcomes was assessed: the primary endpoint was the occurrence of preeclampsia, and the secondary composite outcomes were defined as the occurrence of preeclampsia, heart failure (HF), and pleural effusion within three months after birth.

Results: Of the 406 high-risk pregnant women, 99 (24.4%) had PE. Women with PE were more likely to be younger, have higher blood pressure and soluble suppression of tumorigenicity-2, and develop gestational diabetes mellitus. They had increased left atrial and ventricular volumes, a higher mitral inflow, a lower systolic tissue velocity of the septal mitral annulus, a higher E/e' ratio and pulmonary artery systolic pressure, and a higher frequency of ≥ mild to moderate mitral/tricuspid regurgitation. PE was mainly associated with gestational hypertension. During follow-up, preeclampsia, HF, isolated pleural effusion, and any composite outcome were significantly more prevalent in women with PE. In multivariate analysis, PE was the most significant factor for adverse composite outcomes.

Conclusion: In high-risk pregnant women, PE during the third trimester may be a novel biomarker for preeclampsia and peripartum HF. The timely implementation of echocardiographic surveillance during the third trimester in high-risk pregnant women may be helpful for the earlier recognition of PE, preeclampsia, and HF.