Outcome with beta blocker in the long QT syndrome is good in asymptomatic patients

During a five-year follow-up of 869 patients with a long QT syndrome, the estimated cumulative probability of experiencing aborted cardiac arrest or death on beta blocker therapy was significantly reduced in those who were asymptomatic (0.97 versus 0.31 events per year on therapy in probands and 0.26 versus 0.15 events per year in affected family members). Recurrent events despite beta blocker therapy were significantly higher in those with a history of syncope (hazard ratio 3.1) or aborted sudden death (hazard ratio 12.9).