6. EP Flashcards
(397 cards)
What % of pregnancies have fetal arrythmias?
1-2
What is the most common type of arrhythmia in fetal life?
PACs
80-90%
What % of fetal arrhythmias are sustained?
10%
What can fetal SVT lead to?
- Hydrops
- Reduced ventricular function
(Limits diastolic filling time)
When is treatment indicated in fetal SVT?
- Sustained arrhythmia (>50% SVT burden)
2. Hydrops
What is the first line drug for fetal SVT if there is no evidence of hydrops?
Digoxin
What % of patients respond to digoxin for fetal SVT?
60-80%
What digoxin level do you need to have adequate fetal transfer?
2 (high)
This results in 60% fetal transfer
What happens to the fetal transfer rate of medications if the baby has hydrops?
Decreases by 50%
What are medication options for fetal SVT that is refractory to digoxin or if the baby is hydropic?
- Flecainide
- Sotalol
- Amiodarone
What are treatment options for fetal atrial flutter?
- Flecainide
- Sotalol
- Amiodarone
Which 2 drugs used for fetal arrhythmias have an excellent fetal transfer?
Flecainide and sotalol (80-100%)
What the fetal transfer of amiodarone
Poor, 10-30%
? role for this in infants with more severe hydrops
How early can a fetus with sustained tachycardia develop hydrops?
48 hours
Can adenosine be used in fetal SVT?
Yes, as an injection into umbilical vein
High risk to the fetus
Do isolated PACs require restriction from sports?
No
First line therapy for long QT?
Beta blockers
Risk factors for SCD in LQTS?
- Length of QT interval (>500 greatest risk)
2. Prior syncope
Can amiodarone be used in LQTS?
Relative contraindicated (prolongs QT)
Is a prophylactic ICD recommended in LQTS?
No
Best way to break flutter?
DC cardioversion
What effect does digoxin have on flutter?
Can slow ventricular response, but won’t often terminate the tachycardia
What are 3 drugs that can be used for flutter, but take time for effect and may not convert the rhythm?
- Sotalol
- B-blocker
- Amiodarone
What does a vagal maneuver do to flutter?
Slow ventricular rate so flutter becomes more visible