Gender-Related Changes in Magnetocardiographically Determined Fetal Cardiac Time Intervals in Intrauterine Growth Retardation

Abstract

Prenatal growth deficiencies as well as gender have been associated with cardiovascular disease in later life. It is also known that the duration of fetal cardiac time intervals (CTI) are dependent on fetal development. The aim of this work was to examine the relationship between fetal CTI in healthy and intrauterine growth retardation (IUGR) fetuses, taking gender into account. A total of 269 magnetocardiograms (MCG) were obtained in 47 healthy and 27 IUGR pregnancies. In each signal-averaged MCG, durations of CTI were determined. Age-and heart rate-corrected values were compared between normal and IUGR fetuses separately with respect to gender. Overall, there was an association between atrial and ventricular conduction times and estimated fetal body weight. In female fetuses, IUGR was associated with shorter P WAVE, PQ segment, PR interval, and QRS complex and longer STT and QT intervals. For males, this was so only for P wave, QRS complex, and STT interval. The shortening of conduction times in IUGR may be explained by reduced cardiac muscle mass associated with lower body weight. On the other hand, the gender-specific differences, particularly in the IUGR fetuses may be due to hormonal factors.

Analysis of fetal cardiac conduction times in twin pregnancy using magnetocardiography

“…Thus the shorter conduction times in the twins will most likely reflect their reduced cardiac muscle mass. This effect has previously been noted in growth retarded fetuses [6] however in the twin data presented here, the reduction in CTI duration does not seem to be as great. In IUGR fetuses, disturbance in hormonal status has been postulated to explain effects which cannot be attributed to fetal biometrics alone.…”

“…This is explained by the longer conduction times associated with the increase in cardiac muscle mass as the fetus grows and develops. Consequently, disturbances in fetal development such as in intrauterine growth retardation (IUGR) result in shorter conduction times [6]. In healthy twin pregnancy, fetuses tend to be below average weight for their gestational age and to have lower birth weight and head circumference compared to healthy singletons at the same gestational age [7].…”

Intrauterine growth restriction due to uteroplacental insufficiency decreased white matter and altered NMDAR subunit composition in juvenile rat hippocampi

“…However, sex-specific differences have been previously demonstrated in the response of various organs to UPI-induced IUGR (39), including the brain (35). Using a similar model, other investigators have also demonstrated functional changes in male, but not female, IUGR rats; sex-specific differences in the effects of IUGR on various organs are well known (15,86). Although rats display sexual differences in the hippocampal modulation by corticosteroids (4) as well as in the response to injury (53), the cause for the apparent increased male susceptibility to cerebral effects of UPI found in our study is unclear.…”

Maturing human pluripotent stem cell-derived cardiomyocytes in human engineered cardiac tissues

“…This is because when the curve is steep (slope ≥1) there is an increased susceptibility to alternating beat-to-beat changes in APD (APD alternans) [166], an arrhythmogenic scenario [162]. APD restitution has been demonstrated in both adult and fetal human hearts [156, 164, 167]. …”