The use of propafenone in the treatment of tachyarrhythmias in children

Propafenone was given to 60 children (mean age 4.5 years) withparoxysmal re-entrant supraventricular tachycardia (rSVT: 41cases), postoperative automatic junctional tachycardia (JET:eight cases), automatic atrial tachycardia (AT: four cases),ventricular tachycardia (VT: four cases) and atrial flutter(AF: three cases). In acute cases (29) propafenone was administered intravenously(mean dose 1.3±0.5 mg . kg^–1) chronic oral treatment(mean dose of either 11±3.3 mg . kg. day^–1 or 265±78mg . m^–2 . day^–1) was given to 48 children, in 2–3divided doses. Overall efficacy was 76% for acute and 69% forchronic treatment, with best results in paroxysmal rSVT. Itwas effective in 89% acutely of those treated acutely and in69% of those administered chronically. The efficacy of propafenonein the prevention of rSVT was strictly related to the incidenceof attacks before treatment. propafenone was indeed inefficaciousin 6/11, 6/14 and 0/12 of patients with daily, weekly and monthlyattacks respectively. Side effects were observed in 25% of patients: 6% required suspensionof therapy due to pro-arrhythrnic effects in one patient onintravenous administration, peripheral neuropathy in one caseand hypotension in two postoperative JET patients. In conclusion, its efficacy and limited side effects make propafenonea relatively safe and very useful drug in the treatment of varioustachyarrhythmias. However, risk of unpredictable toxic levelsrequires careful use of the drug especially in the first daysof treatment, when a daily monitoring of ECG is strongly recommended.