Fetal and Neonatal Magnetophysiology
Condition: Fetal Arrhythmia; Abnormality in Fetal Heart Rate or Rhythm; Long QT Syndrome
MeSH terms: Arrhythmias, Cardiac; Long QT Syndrome
Study type: Observational [Patient Registry]

Summary: 
      Fetal research and clinical practice has been hampered by a lack of suitable investigational
      techniques. Currently, ultrasound is the only widely used method of studying fetal anatomy
      and physiology, but it has significant limitations for assessment of cardiac rhythm. The
      proposed study will allow us to investigate fetal magnetocardiography (fMCG) as a new tool
      for the study of normal and abnormal fetal heart rate and rhythm, with a goal of
      demonstrating probable benefit from use of the device in patients with serious fetal
      arrhythmia. We propose a study that will last 1-2 years and will provide data to aid in
      assessing the safety and effectiveness of fMCG for diagnosis and management of patients with
      abnormal fetal heart rate and rhythm. We hope that the data from the study will support a
      Humanitarian Device Exemption (HDE) application for the subject device. The safety and
      efficacy study designs are described below. High-risk subjects will undergo echocardiography
      as part of their routine clinical management, and our results will be compared to the
      echocardiography results, as well as with postnatal ECG, when available. (Since many
      arrhythmias resolve prior to birth, either due to resolution of disease or due to treatment,
      only a limited number of diseases allow postnatal comparison). For rhythms that persist after
      birth, the diagnostic utility of fMCG and echocardiography will be assessed by computing the
      sensitivity (Sn) and specificity (Sp) relative to postnatal ECG for the following prenatal
      modalities: (i) the fMCG, (ii) the original (referral) echo, (iii) if available, the in-lab
      echocardiogram at the time of the fMCG study. Secondary endpoints will assess changes in
      diagnosis and in clinical management due to the additional information provided by fMCG,
      compared to the information provided by echocardiography alone.
    


Intervention name(s): magnetocardiography; postnatal ECG; fetal echocardiography
Intervention type(s): Device; Device; Device
Intervention description(s): recording of magnetic heart activity; postnatal ECG; fetal echocardiography
Other intervention name(s): MCG; fetal magnetocardiography; electrocardiography; Doppler ultrasound; M-mode ultrasound; 2d ultrasound
Observational model: Cohort
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        We plan to study a total of 180 subjects. Sixty will be pregnant women with uncomplicated
        pregnancies; 120 will be pregnant women with pregnancies complicated by fetal arrhythmia or
        a condition that puts the fetus at risk of fetal arrhythmia. We refer to these cases as
        "high-risk" due to the presence of or risk of arrhythmia to the fetus. The pregnant mothers
        will be age 18 or older. They will be studied as early as 15 weeks' gestation and may be
        asked to return, if their physician determines that additional fMCG studies are necessary.
      
Keywords: fetus; fetal arrhythmia; fetal heart rate; long QT syndrome