Postpartum cardiovascular function in patients with hypertensive disorders of pregnancy: a longitudinal study

Abstract

Background: Women with a history of hypertensive disorders of pregnancy are at increased risk of cardiovascular diseases, which are usually mediated by the development of cardiovascular risk factors, such as chronic hypertension, metabolic syndrome, or subclinical myocardial dysfunction. Increasing evidence has been showing that little time elapses between the end of pregnancy and the development of these cardiovascular risk factors.

Objective: This study aimed to assess the persistence of hypertension and myocardial dysfunction at 4 months postpartum in a cohort of women with hypertensive disorders of pregnancy, and to compare the echocardiographic parameters between the peripartum and the postpartum period.

Study design: In a longitudinal prospective study, a cohort of women with preterm or term hypertensive disorders of pregnancy and an unmatched group of women with term normotensive pregnancy were recruited. Women with preexisting chronic hypertension (n=29) were included in the hypertensive disorders of pregnancy cohort. All participants underwent 2 cardiovascular assessments: the first was conducted either before or within 1 week of delivery (V1: peripartum assessment), and the second between 3 and 12 months following delivery (V2: postpartum assessment). The cardiovascular evaluation included blood pressure profile, maternal transthoracic echocardiography (left ventricular mass index, relative wall thickness, left atrial volume index, E/A, E/e', peak velocity of tricuspid regurgitation, ejection fraction, and left ventricular global longitudinal strain and twist), and metabolic assessment (fasting glycemia, insulin, lipid profile, and waist measurement). Echocardiographic data were compared between V1 and V2 using paired t test or McNemar test in hypertensive disorders of pregnancy and in the control groups.

Results: Among 260 patients with pregnancies complicated by hypertensive disorders of pregnancy and 33 patients with normotensive pregnancies, 219 (84.2%) and 30 (90.9%) attended postpartum follow-up, respectively. Patients were evaluated at a median of 124 days (interquartile range, 103-145) after delivery. Paired comparisons of echocardiographic findings demonstrated significant improvements in cardiac remodeling rates (left ventricular mass index [g/m²], 63.4±14.4 vs 78.9±16.2; P<.001; relative wall thickness, 0.35±0.1 vs 0.42±0.1; P<.001), most diastolic indices (E/e', 6.3±1.6 vs 7.4±1.9; P<.001), ejection fraction (ejection fraction <55%, 9 [4.1%] vs 28 [13.0%]; P<.001), and global longitudinal strain (-17.3±2.6% vs -16.2±2.4%; P<.001) in the postpartum period compared with the peripartum. The same improvements in cardiac indices were observed in the normotensive group. However, at the postnatal assessment, 153 of 219 (69.9%) had either hypertension (76/219; 34.7%) or an abnormal global longitudinal strain (125/219; 57.1%), 13 of 67 (19.4%) had metabolic syndrome, and 18 of 67 (26.9%) exhibited insulin resistance.

Conclusion: Although persistent postpartum cardiovascular impairment was evident in a substantial proportion of patients given that more than two-thirds had either hypertension or myocardial dysfunction postpartum, cardiac modifications because of pregnancy-related overload and hypertension were more pronounced in the peripartum than in the postpartum period.

Keywords: cardiovascular diseases; cardiovascular risk; echocardiography; gestational hypertension; global longitudinal strain; hypertension; metabolic syndrome; preeclampsia; pregnancy.