Early cardiovascular changes in hypertensive pregnancies: insights from left atrial strain and compliance

Abstract

Background: Hypertensive disorders of pregnancy (HDP), which include gestational hypertension and preeclampsia, are associated with adverse maternal and fetal outcomes and may result in subclinical cardiac dysfunction. Traditional echocardiographic parameters, including the ejection fraction and Doppler indices, often fail to detect early myocardial and atrial abnormalities.

Objective: To evaluate early cardiovascular changes in pregnant women with hypertensive disorders, with an explicit focus on left atrial (LA) strain and compliance assessed through speckle-tracking echocardiography.

Methods: A prospective observational study was conducted at a tertiary care center, enrolling 73 pregnant women from 20 weeks of gestation onward: 38 with HDPs and 35 with normotensive pregnancies. Transthoracic echocardiography, including two-dimensional speckle tracking, was used to assess global longitudinal strain (GLS), LA strain (reservoir, conduit, contraction), and LA compliance (LASr/E/e'). Standard Doppler and tissue Doppler indices were also evaluated. Logistic regression was used to identify independent predictors of HDP.

Results: Compared with controls, women with HDPs presented significantly lower LA reservoir strain (31.00% vs. 35.00%, p = 0.002), conduit strain (18.00% vs. 24.00%, p < 0.001), and LA compliance (3.87 vs. 5.57, p < 0.001), despite having a preserved ejection fraction. GLS also decreased (19.00% vs. 21.00%, p < 0.001). In the multivariate analysis, decreased LA compliance (OR 0.50, 95% CI 0.33-0.76, p = 0.001) and GLS (OR 1.49, 95% CI 1.08-2.03, p = 0.014) were identified as independent predictors of HDP.

Conclusion: Pregnant women with hypertensive disorders exhibit early subclinical cardiac dysfunction characterized by impaired left atrial (LA) strain and compliance. These advanced echocardiographic parameters may serve as sensitive markers for early cardiovascular changes, providing superior diagnostic value compared with conventional metrics. Routine evaluation of LA strain and compliance could improve risk stratification and guide management in hypertensive pregnancies.

Keywords: Diastolic dysfunction; Hypertensive disorders of pregnancy; LA compliance; Left atrial strain; Preeclampsia; Speckle-tracking echocardiography.