The persistents major ipo or ipercinetic arrhythmies could constitute a condition of “cardiological fetal emergency” and if not in relief and promptly takes care of could conduct the fetus to heart failure and intrauterine death .The worse prognosis when the arrhythmy joins congenital heart disease (CHD).
The most common form of ipercinetic arrhythmies is the supraventricular paroxysmal form that in the 10% of the cases join to structural CHD. The form that imposes a medical treatment the incessant one that it join to heart failure and/or CHD. Less frequent the atrial flutter or fibrillation or ventricular tachicardia.
Between the ipocinetic arrhythmies the most remarkable is the complete a-v block whose prognosis tied to the ventricular frequency . When the ventricular frequency is < to 50 p.m. sever heart failure is the rule and having tried a trans-abdominal pacing without positive effect. This therapeutic approach would be desirable but for a prolonged stimulation
the risk of infections fetal is very elevated . The literature brings again cases sporadic treatises without success with beta stimulating agent ( isoproterenol,ritrodin etc)
The most commonly drugs used are listed in the following chart.
|Transplacental Treatment of Fetal Arrhythmies|
|Digoxin||g. os0.5 – 2 mg. e.v.||0.25 – 1 mg/die os|
|Propranolol||mg e.v. ( 0.04 mg/kg )||80 – 160 mg/die os|
|Verapamil||e.v.||240 – 360 mg/die os|
|Procainamid||e.v.||3 – 4 gr/die os|
|Quinidine||os||1-2 gr/die os|
|Flecainid||e.v.||300 mg/die os|
|Amiodarone||os||600 mg/die os|
**) Fetal heart block may be treated with a loading test dose of Salbutamol e.v. 80 mg/L dextrose 4% solution starting with 4 micrograms/min and increased to 64 micrograms/min during the trial and followed by Salbutamol os 8 mg twice a day until delivery.(Groves and coll.Circ.92:3394:1995)
In heart block with maternal anti-Ro and/or anti La proteins autoantibodies has been used Dexamethasone to the mother dosing 4 mg os once a day mantained until delivery,
(Copel et al.:Am J obstet Gynecol 1384:173:1995)
Correspondence to : S.Gerboni M.D.