(1157) Postpartum Electrocardiogram Parameters in Patients Affected and Unaffected by Cardiovascular Dysfunctions

The postpartum period involves rapid fluid shifts that, combined with preexisting cardiovascular disease or hypertensive disorders of pregnancy, increase cardiac stress. As a widely utilized cardiac assessment, we hypothesize that Electrocardiogram (ECG) may reveal critical cardiac changes in the postpartum period and serve as a screening tool prior to echocardiography. This preliminary study aims to compare trends in four ECG parameters—QTc, QRS duration, PR interval, and heart rate —from 50 weeks before to 10 weeks after birth in patients with and without cardiovascular complications.

Study Design:

This is a retrospective case-control study of a database that includes 26,453 ECGs on 7,637 pregnant individuals aged 18–50 (2011–2024) at a single tertiary center. After excluding patients with pre-existing cardiac morbidity or hypertensive disorders of pregnancy, 3,032 ECGs from 2,407 individuals were included to establish normative trends. Ten individuals with heart failure (pre-existing or peripartum cardiomyopathy) (Figure 1) and 13 patients with preeclampsia who had ECGs from ≥2 gestational periods (pre-pregnancy, during pregnancy, or postpartum) were separately analyzed (Figure 2). 

Results:

In unaffected pregnancies, PR-interval, QRS duration, and QTc remained stable. In contrast, patients with heart failure exhibited elevated QRS duration, QTc, and PR interval throughout the pregnancy and a blunt drop in QTc was seen at birth (Figure 1). Patients with preeclampsia demonstrated elevated QTc at birth compared to the unaffected cohort, while an increase of QTc at birth compared to the weeks leading up to birth (Figure 2).  

Conclusion:
Distinct ECG patterns were observed in patients with heart failure and preeclampsia compared to those with unaffected pregnancies. Notably, QTc and QRS duration were elevated throughout gestation in patients with cardiac complications, with abnormal QTc responses around the time of delivery. These findings suggest that serial ECG monitoring may offer early signals of peripartum cardiovascular stress and warrant further investigation as a potential screening tool.