The use of beta-blocking agents in adults with congestive heart failure has been shown to improve symptoms and outcome; however, experience in pediatric patients with left ventricular systolic dysfunction is limited. We identified 12 pediatric patients treated with beta-blocking agents for left ventricular systolic dysfunction and reviewed echocardiographic indices of left ventricular systolic performance prior to initiation of beta-blocker therapy and at intermediate follow-up. Left ventricular fractional shortening and ejection fraction increased significantly from baseline to intermediate follow-up (13 +/- 4% to 21 +/- 8% [p = 0.01] and 26 +/- 8% to 41 +/- 17% [p = 0.04], respectively). When added to conventional therapy, beta-blocker therapy resulted in an increase in ejection-phase indices of left ventricular systolic performance at intermediate follow-up in pediatric patients with systolic dysfunction.