Download Protocol of fMCG

FMCG protocol
Date:
Time of measurement:
Identification number
of measurement:
System:
1.
Measurement procedure:
1.1. Duration of measurement:
min
 none
1.2. Fetal activity during the measurement:
(from maternal observation)
1.3. Peculiarities during the measurement:
 low
1.4. Shortest distance abdominal surface to valve plane of the fetal heart:
medium
begin of session
mm
end of session
mm
1.5. Distance abdominal surface to cryostat directly above the fetal heart:
2.
2.1.
high
mm
Medical data
Data of the pregnant woman
2.1.1. First name, Surname (only for internal use)
2.1.2. Date of birth:
 no
2.1.3. Chronic diseases persisting during pregnancy:
If yes, which?
Which?
Number of deliveries:
2.1.4. Number of pregnancies (including this):
2.2.
 yes
 Diabetes mellitus
 Adiposity
 Nicotine abuse
 Alcohol abuse
 Other: (see appendix 1)
Data of the present pregnancy and the fetus
2.2.1. Completed week of gestation:
2.2.2. Race
Caucasian
African
Afrocaribian
Asian
South-East Asian/ Chinese:
2.2.3.. Medication during last week:
If yes, which?
2.2.4. Findings during the pregnancy:
mother:





 non
 normal
father:





 yes
 ß- Sympathomimetica
 Calcium antagonists
 Magnesium
 Glucocorticoids
 Other
Which?
 abnormal
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If abnormal, which?
 Gestational diabetes
 Placental dysfunction syndrome
 Premature contractions
 Hypertension
 Gestosis/ Preeclampsia
 Other (see appendix 2)
Which?
2
2.2.5. Ultrasound findings
Placenta localisation:
left

Posterior 
right
  

 
Anterior
 Placenta praevia
 fundal
Amniotic fluid: (Estimation from the greatest sea of amniotic fluid in two planes)
 Oligohydramnios (<4x4)
 regular (>4x4 cm)
 Hydramnios (>12 cm anterior-posterior)
2.2.6. Doppler velocimetry findings: (if investigated, relevant data at time of the fMCG measurement, Reference see
below)
regular
pathologic
values, if pathologic




Right uterine artery:
Left uterine artery:
Umbilical artery
Middle cerebral artery (MCA)
2.2.7. Position




left
right
anterior
posterior
Cephalic position with dorsum


Breech position with dorsum








Transverse position with head
2.2.8. Estimated fetal weight:
g
2.2.9. Heart size (see figure 1, +/- one week of measurement)
Heart length:
mm
Heart width:
Myocardial thickness:
mm
Internal dimensions:
Left ventricle:
mm
Left ventricle:
mm
Right ventricle:
mm
Right ventricle:
mm
Interventricular septum:
mm
2.2.10. Findings of the fetus:
If abnormal, which?
 normal
 abnormal
 Suspected intrauterine growth retardation
 Pathological CTG findings
 Pathological utero-placental velocimetry
 Pathological fetal flow velocimetry
 Suspected congenital heart disease
Which?
 Suspected supraventricular tachycardia
 Suspected ventricular tachycardia
 Bradycardia
 Suspected supraventricular extrasystoles
 Suspected ventricular extrasystoles
 Other: (see appendix 3)
Which?
2.2.11. Cardiotocography: (values)
Basal frequency (bpm)
Band width:(bpm)
Acceleration (number/ 30 min):
Deceleration (no; variable; late):
Oscillations (< 2; 2-6; > 6/ min):
Fisher Score:
Assessment:
2.3.
Date:
Date:
Date:
Data peri- and postnatal
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2.3.1. Date of birth:
2.3.2. Completed week of gestation:
 spontaneous vaginal
 vaginal operative
 female
2.3.3. Mode of delivery
2.3.4. Sex:
 caesarean section
 male
2.3.5. Weight:
2.3.6. Circumference:
g
head:
cm
abdomen:
cm
2.3.7. Apgar (5 minutes):
2.3.8. Base-Excess:
2.3.9. pH (A.umbilicalis):
2.3.10. Diagnosis of the neonate (excluding ECG):
 normal
 abnormal
 Congenital heart disease
If abnormal, which?
Which?
 Premature delivery
 Intrauterine growth retardation
 Perinatal asphyxia/ hypoxia/ cyanosis
 Other: (see appendix 4)
Which?
 no
2.3.11. Neonatal ECG:
 yes
 abnormal
 normal
 Supraventricular tachycardia
 Ventricular tachycardia
 Bradycardia
 Supraventricular extrasystoles
 Ventricular extrasystoles
 Atrioventricular block
 Other: (see appendix 5)
Findings of the neonatal ECG:
If abnormal, which?
Which?
ECG in accordance with fMCG?
2.3.12. Placenta
 no
 yes
weight:
g
histology:
3.
2.1.
2.2.
2.3.
2.4.
Recommended recording parameter:
High pass filter:
Low pass filter:
Sampling frequency:
Notch filter:
<= 2 Hz
80-500 Hz
1000 Hz
off
2.5. Minimum time of measurement for averaged signal:
2 min
2.6. Minimum time of measurement for FHRV:
5 min
After averaging a SNR of at least 10 should be obtained. (Estimation from the best recorded channel.)
Noise estimation from a 5-20 ms window with minimum drift, shift for minimum noise.
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4.
Guidelines to data analysis
To obtain the specific data from fetal magnetocardiographic recordings the following processing steps are
recommended:
Averaging
A high quality averaged fetal PQRST-complex is required for the determination of the time intervals. Band pass (1 –
200/500 Hz) filtered raw data is recommended to be used after template or R-peak based averaging. Smoothing filters
may be used for template definition and search. To reduce the influence of the maternal MCG, these PQRSTcomplexes may be required to be averaged first and subtracted from the recorded data before processing of the fetal
MCG can be commenced. A control of plausibility (i.e. observation of a beat to beat variability plot or FHR trace) may
be used to secure validity of the average.
4.1.
Offset / Baseline correction
This may be required after averaging and should be performed from a 5 to 20 ms (as long as possible) iso-magnetic
interval either before the onset of the P wave or from the PQ segment
4.2.
Determination of the time intervals
Manual definition of length of P wave, PR interval, QRS complex and QT interval is best performed from unfiltered
averaged data. If otherwise filtered data was used, this needs to be specified in the protocol. Onset and offset of the
time intervals are defined from the first/last ‘deflection from the zero-line’/event in any of the channels available in
each system.
4.3.
Protocol of a recording
After analysis a complete data set should contain:
number of template matches found
duration of the whole fetal signal and all signal parts according to the definitions given below
qualitative, semi - quantitative or quantitative assessment of fetal activity during the recording (i.e. ultrasound
check, online assessment for low frequency artifacts, information from the mother etc.)
5.
Definitions of the cardiac time intervals (see figure 2)
P wave:
QRS complex:
T wave:
PQ segment:
ST segment:
PR interval:
QT interval:
onset until the end of atrial excitation
onset of the Q peak until the end of the S peak
onset of the T wave until the end of the T wave
isoelectric line from the end of the P wave until the onset of the QRS wave
isoelectric line from the end of the QRS complex until the onset of the T wave
duration of time between beginning of the P wave and the beginning of the QRS complex
duration of time between the beginning of the Q wave to the end of the T wave
All values in milliseconds.
Determination of the length of the segments by assessment of as many channels as available:
1. onset determination from the channel with the first event.
2. offset determination from the channel with the final return back to baseline
6.
Definitions of the parameters of the fetal heart rate variability
Observed deviations within the train of beat-to-beat intervals (artifacts, ectopic beats) require assessment of their
possible patho-physiological impact before sufficient algorithms to remove them can be applied. In general HRV
analysis is based on normal-to-normal (NN) heart beat intervals and the method of artifact rejection should be
detailed when the results are presented.
Heart rate:
number of heart beats per minute
RR interval:
distance between two successive R peaks (in milliseconds)
SDRR:
standard deviation of all RR intervals (in milliseconds)
RMSSD:
root mean square of successive differences (in milliseconds)
7.
Reference for doppler ultrasound findings:
Kurmanavicius, J., Florio, I., Wisser, J., Hebisch, G., Zimmermann, R., Müller, R., Huch, R., Huch, R. (1997).
Reference resistance indices of the umbilical, fetal middle cerebral and uterine arteries at 24-42 weeks of gestation.
Ultrasound Obstet. Gynecol., 10, 112-120
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Appendix 1: Chronic diseases persisting
during pregnancy
1.
Several diseases persisting during pregnancy
1.1. Cardiac
1.2. Pulmonary
1.3. Hepatic
1.4. Renal
1.5. Central nervous
1.6. Psychiatric
2. Coagulopathy (disturbances of haemostasis)
3. Severe psychological diseases
4. Severe social diseases
5. Rhesus incompatibility
6. Microsomia
7. Skeletal abnormalities
8. Disturbances of thyroid function
9. Collagenosis
10. Exposure to external noxa
10.1. Radiation
10.2. Medication (i.e. chemotherapy)
10.3. Chemicals (heavy metals, carbon monoxide)
Appendix 2: Course of the present pregnancy
11.
12.
13.
14.
15.
16.
17.
Vaginal bleeding
Twins/ Triplets
Unknown conceptional age
Anaemia
Proteinuria (>1000 mg/l)
Oedema
Hypotension
Appendix 3: Fetal risk
18. Suspected fetal cardiac diseases
18.1.
Ventricular septal defect
18.2.
Atrial septal defect
18.3.
Fallot’s tetralogy
18.4.
Transposition of great arteries
18.5.
Pulmonary stenosis
18.6.
Myocardial hypertrophy
18.7.
Miscellaneous
19. Miscellaneous suspected fetal abnormalities
Appendix 4: Perinatal/ Postnatal diagnosis (without
cardiac diseases and ECG findings )
20.
21.
22.
23.
24.
25.
26.
27.
28.
29.
30.
31.
32.
33.
34.
35.
36.
37.
38.
39.
40.
IRDS/ cardiopulmonary diseases
Shock
Haematological diseases
Metabolic disturbances
Hereditary metabolic defects
Thyroid diseases
Diseases of the blood
Intracranial haemorrhage
Convulsions/ neonatal encephalopathy
Trauma/ fractures/ pareses
Septicaemia
Chromosomal abnormalities
Anencephalus, hydrocephalus, microcephalus
Neural tube defects
Abnormalities of eye/ ear/ neck
Respirational abnormalities
Gastrointestinal abnormalities
Genitourinal abnormalities
Skeletal abnormalities
Diaphragmatic defects, hernias
Miscellaneous
Appendix 5: Cardiac diseases and findings of the
neonatal ECG
41.
42.
43.
44.
45.
46.
47.
Ventricular septal defect
Atrial septal defect
Fallot’s tetralogy
Transposition of major arteries
Pulmonary stenosis
Myocardial hypertrophy
Miscellaneous
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