Magnetocardiographic identification of prolonged fetal corrected QT interval in women receiving treatment for opioid use disorder

The magnetocardiogram

The magnetic field produced by the heart's electrical activity is called the magnetocardiogram (MCG). The first 20 years of MCG research established most of the concepts, instrumentation, and computational algorithms in the field. Additional insights into fundamental mechanisms of biomagnetism were gained by studying isolated hearts or even isolated pieces of cardiac tissue. Much effort has gone into calculating the MCG using computer models, including solving the inverse problem of deducing the bioelectric sources from biomagnetic measurements. Recently, most magnetocardiographic research has focused on clinical applications, driven in part by new technologies to measure weak biomagnetic fields.

2023 HRS expert consensus statement on the management of arrhythmias during pregnancy

This international multidisciplinary expert consensus statement is intended to provide comprehensive guidance that can be referenced at the point of care to cardiac electrophysiologists, cardiologists, and other health care professionals, on the management of cardiac arrhythmias in pregnant patients and in fetuses. This document covers general concepts related to arrhythmias, including both brady- and tachyarrhythmias, in both the patient and the fetus during pregnancy. Recommendations are provided for optimal approaches to diagnosis and evaluation of arrhythmias; selection of invasive and noninvasive options for treatment of arrhythmias; and disease- and patient-specific considerations when risk stratifying, diagnosing, and treating arrhythmias in pregnant patients and fetuses. Gaps in knowledge and new directions for future research are also identified.

Systematic Review: Polysubstance Prevalence Estimates Reported during Pregnancy, US, 2009-2020

INTRODUCTION

The objective of this systematic review is to describe polysubstance studies and their prevalence estimates among pregnant people in the US.

METHODS

This review was not subject to protocol preparation or registration with the International Prospective Register of Systematic Reviews (PROSPERO) because outcome data were not reported. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) Checklist was followed. Four scientific literature databases were used to identify articles published from January 1, 2009 to June 3, 2020 reporting prenatal exposure to two or more substances in the US. A standardized process of title and abstract screening followed by a two-phase full-text review was used to assess study eligibility.

RESULTS

A total of 119 studies were included: 7 case-control studies, 7 clinical trials, 76 cohort studies, and 29 cross-sectional studies. Studies varied with respect to study design, time period, region, sampling and participant selection, substances assessed, and method of exposure ascertainment. Commonly reported polysubstance prevalence estimates among studies of pregnant people included combinations with alcohol, marijuana, and/or tobacco/nicotine. The range of prevalence estimates was wide (alcohol 1-99%; marijuana 3-95%; tobacco/nicotine 2-95%).

DISCUSSION

Polysubstance use during pregnancy is common, especially with alcohol, marijuana, and/or tobacco/nicotine. Future research to assess polysubstance use during pregnancy could help better describe patterns and ultimately help mitigate its effects on maternal and infant health outcomes.

Impact of prenatal opioids on cardiac and autonomic development: systematic review and meta-analysis

Prenatal opioid exposure has recently risen four-fold with limited data on the developmental effects on neonatal physiology. The objective of this systematic review is to develop an association between prenatal opioid exposure and fetal and neonatal cardiac and autonomic development and function. The review was conducted in accordance with PRISMA Guidelines, and searches were conducted using PubMed, Embase, CINAHL, and Web of Science between May 25 and October 27, 2020. Twenty studies fit inclusion criteria, in four categories: (1) fetal cardiac outcomes, (2) neonatal cardiac outcomes, (3) noninvasive autonomic outcomes, and (4) clinical and behavioral measures. For the meta-analysis, three studies (total of 210 subjects) were included. Effect sizes were measured as the mean difference in fetal heart rate between opioid-exposed and non-exposed groups. Mothers with prenatal opioid use had a significantly lower fetal heart rate as compared to mothers without prenatal opioid use, requiring further studies to determine clinical significance.

Dynamics of the use of magnetocardiography in the study of the cardiac conduction system of the chick embryo

INTRODUCTION

Human fetal magnetocardiography (fMCG) has been done for several decades to evaluate fetal arrhythmias using a superconducting quantum interference device (SQUID) magnetometer, but there is little work in embryonic/fetal animal models. This study uses an optically-pumped magnetometer (OPM) to obtain an fMCG in the chick embryo.

METHODS

White Leghorn chick embryos were examined from incubation Day #10-19. Different examination chambers were tested to optimize embryonic thermal stability and magnetic signal acquisition. All examinations were done with magnetic shielding. The OPM sensors were placed next to the egg shell. The embryo's position was localized by transilluminating the intact egg or ultrasound imaging the egg with an open air cell to optimize sensor placement. The raw data for each embryo was postprocessed to obtain a fMCG composite waveform.

RESULTS

fMCG's were obtained in embryos from Day #12 to 19. The best success with intact eggs was obtained using five sensors; one at the bottom and four around the lower perimeter of the egg at 90° intervals with the egg oriented vertically and the air cell up. Using ultrasound imaging with the air cell open only two sensors were necessary, one at the bottom and one laterally next to the embryo. fMCGs were analyzed for heart rate and rhythm, each portion of the PQRST waveform, and the PR interval, QRS complex, RR interval, and QT interval.

CONCLUSIONS

This study validates the chick embryo as an animal model to study in a longitudinal and noninvasive fashion the fetal cardiac conduction system by using OPM magnetocardiography.