Flecainide as first-line treatment for supraventricular tachycardia in newborns.
BACKGROUND
Flecainide for the treatment of supraventricular tachycardia (SVT) in newborns is still controversial because of its potentially severe proarrhythmic effects.


RESULTS
Between January 2004 and December 2006, we used flecainide to treat 20 consecutive newborns (15 males) with paroxysmal SVT without any structural heart disease. Their age at hospitalization was 11.5 +/- 11.1 days. The intravenous administration of flecainide (1 mg/kg) effectively restored sinus rhythm in all the patients. Once stable sinus rhythm had been restored, the drug was administered orally at a dose of 2 mg/kg/day twice daily, which was uptitrated as the patients gained weight. The patients were followed up for up to 24 months with clinical evaluations, baseline ECG and 24-h Holter monitoring every 3 months. There were neither deaths nor any episodes of heart failure or sustained ventricular tachycardia during follow-up. SVT were completely controlled in 17 patients (85%), with an oral dose of 3.35 +/- 1.35 mg/kg/day of flecainide; in the remaining three patients with refractory arrhythmias, propranolol was added for optimal treatment. No significant increase in the duration of QRS (70 +/- 1.09 vs. 63.8 +/- 1.87 ms, P = NS) or any significant QTc prolongation (413 +/- 7.4 vs. 412.6 +/- 8.01 ms, P = NS) was observed. One patient developed an incomplete right bundle branch block promptly reverted by reducing the dose.


CONCLUSIONS
This preliminary experience indicates that flecainide is well tolerated and effective as first-line treatment for paroxysmal SVT in newborns without structural heart disease.
Ferlini
Marco
M
Department of Cardiology, Fondazione IRCCS Ospedale Maggiore Policlinico, Mangiagalli e Regina Elena, Italy.
Colli
Anna M
AM
Bonanomi
Carla
C
Salvini
Laura
L
Galli
Maria A
MA
Salice
Patrizia
P
Ravaglia
Romana
R
Centola
Marco
M
Danzi
Gian B
GB
D000284:Administration, Oral; D000889:Anti-Arrhythmia Agents / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D004359:Drug Therapy, Combination; D015716:Electrocardiography, Ambulatory; D005260:Female; D005424:Flecainide / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D006801:Humans; D007231:Infant, Newborn; D007262:Infusions, Intravenous; D008297:Male; D010865:Pilot Projects; D011433:Propranolol / Q000627:therapeutic use; D011446:Prospective Studies; D013614:Tachycardia, Paroxysmal / Q000188:drug therapy*; D013617:Tachycardia, Supraventricular / Q000188:drug therapy*; D013997:Time Factors; D016896:Treatment Outcome
D000889:Anti-Arrhythmia Agents; D011433:Propranolol; D005424:Flecainide