Effectiveness and Limitations of β-Blocker Therapy in Congenital Long-QT Syndrome

Abstract

Background—β-blockers are routinely prescribed in congenital long-QT syndrome (LQTS), but the effectiveness and limitations of β-blockers in this disorder have not been evaluated. Methods and Results—The study population comprised 869 LQTS patients treated with β-blockers. Effectiveness of β-blockers was analyzed during matched periods before and after starting β-blocker therapy, and by survivorship methods to determine factors associated with cardiac events while on prescribed β-blockers. After initiation of β-blockers, there was a significant (PConclusions—β-blockers are associated with a significant reduction in cardiac events in LQTS patients. However, syncope, aborted cardiac arrest, and LQTS-related death continue to occur while patients are on prescribed β-blockers, particularly in those who were symptomatic before starting this therapy.