Fetal Heart Ultrasound, How, Why and When

Fetal Heart Ultrasound

How, Why and When

By Catherine Fredouille, MD, Part-time Hospital Practitioner, Fetal Placentology Unit, Hopital de La Timone, Marseille. Consultant in Fetopathology, Service de Cytogenetique et de Foetopathologie, Hopital Saint Antoine, Paris, France; and Jean-Eric Develay-Morice, MD, Ultrasonographer, Nimes Maternity Service, Hopital Carremeau, Nimes, France


1. Fetal Heart Ultrasound: WHY

Introduction.
General Notions.
Review.
Application to Fetal Cardiopathies.
References.

2. HOW: Technical Aspects

Physical principals of Ultrasound applied to fetal ultrasound.
Reflection of ultra sound waves.
The shortest pathway.
Getting around obstacles.
From the point of view of time.
Physical principles of Doppler.
New techniques linked to volume acquisition.
Practical controls.
Elements to Set Permanently.
The zoom.
The focus.
Gain.
Pre-set elements.
The dynamic range.
The frequency.
Beamline density.
Persistence.
Contours.
Doppler settings.
The size of the ?box.?
The incident wave direction.
PRF.
Color gain.
The use of Ultrasound in examining the fetal heart.
Echo-structure.
The fetal heart position.
Movements of the target.
Technical Pitfalls.
Problems linked to exposure in the zone of interest.
Ultrasound windows.
Setting Pitfalls.
Further Reading.

3. HOW: Anatomic ? ultrasound correlations: 3 steps, 10 key points

1st step: Position: 2 key points.
Lateralization.
Organs.
Vessels.
The axis of the heart.
2nd Step, Inflow: 4 key points.
Heart, Diaphragm and pulmonary veins.
4 Chambers.
Contractile, balanced, Concordant.
Crux-of-the-Heart, rings and offsetting.
3rd step, Outflow: 4 key points.
2 balanced Outlet chambers with the alignment of the septum.
2 superimposed and crossed arched vessels.
Balanced and Concordant.
Regular Aortic Arch.
References.

4. HOW: Conducting the examination and its pitfalls

Taking the history.
A Fast glance.
Views verifying the 10 key points and their pitfalls.
The ?lift?, verification of the position and its pitfalls.
The technique.
Its pitfalls: elements of lateralization.
Organ position.
Vessel position.
The four chamber view: inlet verification and its pitfalls.
The technique.
Axial apical pathway.
Crux-of-the-heart.
Pitfalls.
The Ao and apex of the heart on the same side to the Left.
The heart's axis.
The Swings.
Lateral fluctuation: asymmetries.
Anterior-posterior movements: false AVSD and false VSD.
View LV-Aorta.
Axial-apical view.
Axial lateral view.
"SOS" view: Sagittal and its pitfalls.
View RV-PT.
Axial view.
Small axis view and its pitfalls.
The 3 vessel or 2 arches view.
Pitfalls.
Sagittal view and the aortic arch.
Pitfalls.
Further Reading.
References.

5. WHY: Critical cardiac pathologies not to be overlooked

1st Step: Position pathologies: 2 key points.
Position anomalies of the organs, of situs.
Vessel Position.
Anomalies of the Position of the Heart.
In the right thorax.
Heart axis.
2nd Step: Inlet Pathologies: 4 key points.
Anomalies of pulmonary venous return.
Irregular number of chambers: 3, 4+ or 5 chambers.
Unbalanced.
Abnormalities of the atrioventricular valves: atresia of one AV valve and the Spectrum of AVSD.
3rd Step: Outflow pathologies: 4 key points.
VSD misalignment in CTC.
Complete transposition of the great vessels.
Hypoplasia of the Left tract, ventricular-arterial discordances and position errors.
Aortic Coarctation of the Ao, Interruption of the Aortic arch.
References.

6. WHEN: Fetal morphological examination after the discovery of a cardiopathy

Unknown Karyotypes.
Investigation for signs associated with the principal chromosomal anomalies.
Normal known karyotype.
Investigation of a micro-deletion 22 q11 or signs linked with Associations, or genetic syndromes.
Cardiopathy and Intra uterine retarded growth (IURG).
Fetal alcohol syndrome.
VACTERL syndrome.
References.

7. Points to remember

Technical points.
Key points in the heart exam.
Morphology.
Further Reading.