1. Fetal arythmia for obstetricians
Prof David Baud, MD PhD
Head of Obstetrics
Lausanne, Switzerland

4. Fetal arythmia
Thanks Edgar T Jaeggi

5. Nœud sinusal

7. Passive filling
of the ventricles

8. ACTIVE filling
of the ventricles

11. How to measure ?

12. Measure simultaneously the activity of the atria & ventricles
How to measure ?
Measure simultaneously the activity of the atria & ventricles
Movements Flux

13. How to measure ?
M-Mode

14. How to measure ?
Dopplers

15. How to measure ? Dopplers Entry-Exit of left ventricle 4 chambers
Mitral valve & aorta

16. How to measure ? Dopplers Entry-Exit of left ventricle
Max 150 msec (mean + 3 SD)

17. 1st degree AV-Block

18. Lupus Prolonged AV interval Normal atrial & ventricular rates (1:1)
Intermittent episodes of AV-Block
Beats without AV-conduction
Complete dissociation between atrial (>120) and ventricular (50-70) events

19. How to measure ?
Dopplers
SVC & aorta
Sagital view

20. in SVC due to atrial contraction
Virtual ECG (a) and real SVC/AA Doppler recording(b) in normal sinus rhythm. Ventricular ejection (V) in the AA appears above baseline. Venous flow is typical with systolic (S) and diastolic (D) waves below baseline and the retrograde flow wave (A) due to the atrial contraction above. AV interval can be measured from the onset of the A wave to the onset of the V wave. A = diastolic retrograde wave; AA = ascending aorta; AV = atrioventricular interval; D = diastolic antegrade wave; ECG = electrocardiogram; S = systolic wave; SVC = superior vena cava; V wave = ventricular ejection.
A=Reverse flow
in SVC due to atrial contraction

21. Arythmias:
irregular
too slow
too fast
Intermittent
Continuous

23. Arythmias Incidence 1% 90% MINOR 10% MAJOR
- Premature atrial contractions
- Transient sinus bradycardia
- Transient sinus tachycardia
10% MAJOR
- Persistent bradycardia 50%
- Persistent tachycardia 50%

24. Arythmias:
irregular
too slow
too fast
Intermittent
Continuous

25. PREMATURE ATRIAL CONTRACTION

26. PREMATURE ATRIAL CONTRACTION
Ectopic
focus
CONDUCTED
NON CONDUCTED

27. PREMATURE ATRIAL CONTRACTION
Mainly benign, hemodynamically insignificant and transient
BUT:
- in 1% progression to SVT
- in 2% associated CHD
Echocardiography
Weekly heart rate control

28. Arythmias:
irregular
too slow
too fast
Intermittent
Continuous

29. Arythmias: irregular too slow too fast Sinus Bradycardia
Non-conducted atrial bigeminy
AV-Block

30. TOO slow = Refer QUICKLY
Rasiah, Fet Diag Ther, 2011

31. Sinus Bradycardia Low HR (70-110/min) Rythm A = V
AV conduction time = normal
If not asphyxia, Echocardio

32. Bigéminisme atrial bloquéV V A2 A A A2 A A2
Rythme atrial irrégulièrement régulier
Rythme ventriculaire régulier lent (60/min)
Pas de TTT, résolution souvent spontanée

33. AV-Block Normal Atrial rate, but do not pass AV-node
Slow regular ventricle rate (60/min)
Refer

34. Arythmias:
irregular
too slow
too fast
Intermittent
Continuous

35. Tachycardia
REENTRY
60% of SVT
1:1
bpm
60% continuous V A

36. Tachycardia REENTRY ATRIAL FLUTTER 60% of SVT 30% of SVT 1:1
bpm
60% continuous
30% of SVT
1:1 => 1:4
A=400, V=200
85% continuous A V V A V

37. Admit patient for treatment
Tachycardia
Admit patient for treatment
=>
Maternal Arythmia

38. Tachycardia Urgent referral (if hydrops) Options:
- Wait if intermittent
- Pharmacological treatment via mother
- Direct fetal treatment
- Delivery if term baby (by CS)

39. Take home message In emergency order: - Bradycardia
- Tachycardia (++ if hydrops)
- Irregular rates