Detection of peripartum myocardial burden by vector-projected 187 channel electrocardiography and serum NT-proBNP

Abstract

There is no reliable method of screening for pregnant women at high risk of developing severe myocardial disorders. In this study, we used vector-projected 187 channel electrocardiography (DREAM-ECG) and serum biochemical markers to evaluate peripartum myocardial burden in pregnant women. Forty-one pregnant women were examined at 36-37 weeks gestation (GW36), 7 days postpartum (PPD7), and 1 month postpartum (PPM1). Ten non-pregnant control women were assessed at a single time point. Heart rate, sympathetic index, and repolarization index (RTc dispersion) were quantifed using the DREAM-ECG system, and serum levels of NT-proBNP, cardiac troponin T, estrogen, and progesterone were determined. Heart rate and the sympathetic index decreased from GW36 to PPM1 (P = 0.0031). The re-polarization index decreased over time and was greater than in non-pregnant controls (31 ± 13 ms). Estrogen and progesterone at PPD7 and PPM1 were signifcantly lower than those at GW36 (P < 0.0001, P < 0.001). NT-proBNP at PPD7 was greater than at GW36 (median 29 pg/mL at GW36, 86 pg/mL at PPD7), and decreased at PPM1 in comparison to PPD7 (median 18.5 pg/mL). Troponin T was in the normal range during the whole period (< 0.003 ng/mL). In conclusion, these results indicate that the peripartum myocardial burden in pregnant women does not return to normal non-pregnant levels by PPM1. We propose that both repolarization indexes such as RTc dispersion by DREAM-ECG and serum biochemical markers may identify pregnant women at high risk of developing severe myocardial damage in the peripartum period.