Abstract Body: Background: There is ongoing debate about hypertension (HTN) management during pregnancy with a range of recommended targets. Whether HTN is related to subclinical cardiac injury during pregnancy is unclear.
Objective: To determine the relationship between HTN with subclinical cardiac injury during and immediately after pregnancy, measured via high sensitivity troponin I (hs-cTnI).
Methods: In a prospective, 1:1 case-control design, we enrolled pregnant women with and without HTN between 24-32 weeks gestation (2019-2022). HTN cases were defined by a clinician diagnosis at <20 weeks gestation or a baseline blood pressure (BP) ≥140/90 mm Hg. The control group (no HTN) had a systolic BP <120 mm Hg. Hs-cTnI was collected at baseline, the delivery admission, and postpartum day 1. We used mixed effects tobit models to compare the groups on log-transformed hs-cTnI, adjusted for age and BMI.
Results: The mean age of the HTN group (N=38) was 33.6 (SD 5.4) vs. 30.3 (5.8) years for the no HTN group (N=38). Mean (SD) baseline BP was 131.1 (14.7)/88.2 (13.5) for the HTN group and 110.1 (7.2)/70.9 (8.2) mm Hg for no HTN. At baseline, hs-cTnI was 1.3 (0.2) in the HTN group and 0.6 (0.1) ng/L in the no HTN group (Figure). Compared to baseline, hs-cTnI increased 89.1% (95% CI: 27.3-180.8%) and 322% (192-511%) for the HTN group, and 101.6% (41.0-188.3%) and 165.2% (88.6-272.9%) for no HTN at delivery and postpartum, respectively. Across all time points, the HTN group had a higher hs-cTnI of 1.05 (0.07-2.03) ng/L compared to the control group.
Discussion: HTN was associated with subclinical cardiac injury during and immediately postpartum. These findings support recommendations to control HTN throughout pregnancy to reduce cardiac injury.