Increase in hs-cTnI rare during normal delivery

Assessment of high-sensitivity cardiac troponin I (hs-cTnI) trajectories during the immediate peripartum period hint at delivery as a physiologic cardiovascular “stress test,” according to a study.

Specifically, pre-eclampsia correlates with greater myocardial stress compared with normotensive pregnancies, with patients with hypertension showing intermediate changes.

In this retrospective cohort study, the authors assessed peripartum hs-cTnI dynamics and compared phenotype-specific patterns among pre-eclampsia, hypertension, and normotensive controls. They analysed leftover serum or EDTA plasma samples obtained within 48 h of delivery.

Mixed-effects linear regression models were used to examine log10-transformed hs-cTnI concentrations and temporal slopes, with adjustments for demographic and obstetric covariates.

A total of 609 participants were included, comprising 90 pre-eclampsia, 116 hypertension, and 403 normotensive control patients. The median hs-cTnI concentrations were <2.5 ng/L prior to delivery across all groups and increased significantly following delivery. Pre-eclampsia had the highest postdelivery increase, followed by hypertension and normotensive controls.

Multivariable analyses revealed higher hs-cTnI levels in pre-eclampsia compared with normotensive controls (β, 0.266; p<0.001) and hypertension (β, 0.160; p=0.011). Hypertension was also higher than normotensive controls (β, 0.107; p=0.046).

Furthermore, steeper peripartum hs-cTnI slopes were observed in pre-eclampsia vs normotensive controls (β, 0.005/h/ p=0.013). On the other hand, slopes were not significantly different between pre-eclampsia and hypertension.

“These data indicate that marked increases in hs-cTnI are rare during normal deliveries and deserve additional diagnostic evaluation,” the authors said.