Women with histories of hypertensive disorders of pregnancy (HDP), including pre-eclampsia and gestational hypertension, saw pronounced differences in heart structure and function a decade after pregnancy, according to the authors of a 132-subject study.
They called for “more aggressive” preventive strategies, further investigations to understand the mechanisms behind HDP with later hypertrophic ventricular remodeling and the development of therapeutic interventions that prevent adverse outcomes.
The findings were published online on Monday in the March 2 issue of the Journal of the American College of Cardiology, with study authors led by Malamo E. Countouris, MD, from the University of Pittsburgh Medical Center Heart and Vascular Institute.
HDP are associated with short-term cardiac structure and function abnormalities; however, prolonged cardiac changes are not well-studied, the researchers said.
The study’s aim was, therefore, to determine whether HDP history is associated with echocardiographic differences 8 to 10 years after giving birth. Subgroup analyses of placental maternal vascular malperfusion (MVM) lesions or current hypertension were also performed to see whether these groups may be particularly affected.
The researchers included 132 women identified from an ongoing 498-subject study investigating placental vascular lesions, adverse pregnancy outcomes and postpartum cardiovascular disease. They were recruited around 10 ±1 years (average age 38 ± 6 years) after pregnancies that delivered between 2008 and 2009, with abstracted pregnancy and placental pathology data.
Women who were currently pregnant, had a diagnosis of chronic hypertension prior to pregnancy, or had clinical cardiovascular disease, including congenital heart disease, valvular heart disease, myocardial infarction, cardiomyopathy, heart failure, or stroke, before the index pregnancy were excluded.
Subjects underwent transthoracic two-dimensional echocardiograms between 2017 and 2020 to obtain measurements of left ventricular (LV) interventricular septum (IVS) thickness, LV posterior wall (PW) thickness, and LV end-diastolic diameter according to American Society of Echocardiography (ASE) guidelines.
Of these women, 30 had experienced HDP – 21 with pre-eclampsia and nine with gestational hypertension – while 102 were normotensive.
Those with HDP history were more likely to have current hypertension (63% vs. 26%) 8 to 10 years after delivery, the researchers said.
They were also more likely to have diabetes (20.7% vs. 7%), higher systolic blood pressure (125 ± 12 mmHg vs. 114 ± 13 mmHg), higher diastolic blood pressure (82 ± 10 mmHg vs. 74 ± 9 mmHg), and saw a trend toward a higher proportion of placental MVM lesions during pregnancy (63.3% vs. 45.1%).
After a linear regression model adjusting for age and race, patients with HDP history had higher LV wall thickness, higher biplane LV ejection fraction, lower mitral inflow E/A ratio, and higher relative wall thickness (RWT) compared to those who did not have HDP.
Modeling adjusting for all of these factors, plus placental MVM lesions, body mass index (BMI), current hypertension and hemoglobin A1c and HDP history, showed that HDP history was still associated with higher LV IVS thickness (hazard ratio [HR]: 3.8; 95% confidence interval [CI]: 1.2 to 6.4; p = 0.04), as well as higher RWT (HR: 0.04; 95% CI: 0.003 to 0.080; p = 0.04).
Subgroup analyses for women with only pre-eclampsia history – instead of the combined HDP variable with both pre-eclampsia and gestational hypertension – yielded “similar results” to normotensive women, the researchers added.
However, women with both HDP history and current hypertension had a higher proportion of LV remodeling (79%) compared with all other groups.
The findings suggest a “double-hit” phenomenon of HDP history and current hypertension, which the researchers urged warrants closer surveillance and early targeted therapies for cardiovascular disease prevention in this higher risk group.
“The main finding of this study was that women with HDP history have increased LV wall thickness compared with women who did not have HDP when evaluated nearly 1 decade after delivery,” the researchers said.
“Furthermore, our stratified analyses reveal that women with both HDP history and current hypertension are the highest-risk group, as they have the most pronounced echocardiographic differences, with almost 80% having LV remodeling, which could in turn account for differences we observed in diastolic function parameters and GLS [global longitudinal strain].”
In an accompanying editorial, Melinda B. Davis, MD, from the University of Michigan, said the study serves to further understanding of the long-term cardiac implications of HDP.
She warned, however, that the researchers “may have underestimated the prevalence of hypertension by relying on office readings and medication history” to define its presence. “Undertreatment of hypertension also contributes to adverse cardiac remodeling with irreversible changes occurring over time, particularly in women,” she said.
In a press statement from the University of Pittsburgh, lead author Countouris added: “Hypertension is a silent killer.
“None of the women in our study had clinical symptoms of heart disease – they are young and probably feel well and healthy, and may not be seeing a health care provider regularly – but it’s important to start screening them for high blood pressure early.”
Preventative methods such as changes in lifestyle or diet can counter cardiovascular risk factors and prevent issues later in life if at-risk patients are identified during this “window of opportunity,” she added.
Countouris ME, Villanueva FS, Berlacher KL, et al. Association of Hypertensive Disorders of Pregnancy With Left Ventricular Remodeling Later in Life. J Am Coll Cardiol 2021;77:1057-68.
Davis MB. Long-Term Left Ventricular Remodeling After Hypertensive Disorders of Pregnancy: Beyond the Hype. J Am Coll Cardiol 2021;77:1069-72.