The efficacy and safety of oral
nadolol in
supraventricular tachycardia were evaluated prospectively in 27 children (median age 5.5 years). Fifteen patients had an unsuccessful trial of
digoxin therapy. Intravenous
nadolol was given to seven patients during electrophysiologic study; five of these had an excellent response and two had a partial response (25% decrease in
tachycardia rate). Six of these patients had a similar response to oral
nadolol. Twelve patients received both
propranolol and
nadolol. Among six patients, intravenous
propranolol was successful in four and unsuccessful in two; all six had a similar response to oral
nadolol. With oral
propranolol,
tachycardia was well controlled in four patients and persistent in two; five of five patients had a similar response to oral
nadolol. Twenty-six patients were treated with oral
nadolol; the
arrhythmia was well controlled in 23, 2 had recurrent
tachycardia and 1 patient had
tachycardia at a 25% slower rate. The effective dose of
nadolol ranged between 0.5 and 2.5 mg/kg
body weight once daily (median dose 1 mg/kg per day). During follow-up (3 to 36 months), compliance and tolerance were excellent; excluding 2 patients with reactive airway disease who developed
wheezing, only 3 (12%) of 24 had side effects necessitating a change in
drug therapy. Once a day
nadolol is a safe and effective agent in the management of
supraventricular tachycardia in children. Its long-term efficacy can be predicted by the short-term response to intravenous
nadolol or
propranolol during programmed electrophysiologic study.