Introduction: Beta-blocker (BB) therapy is very effective in preventing Sudden Cardiac Death (SCD) and syncope in patients with Long QT Syndrome (LQTS). In patients who had cardiac events while treated with BB, Left Cardiac Sympathetic Denervation (LCSD) has been shown to be effective treatment in the short term. However, long term outcomes with LCSD are not available.
Methods: We studied 57 patients with LQTS who had LCSD after BB treatment failure, from the Rochester, New York LQTS registry. The primary endpoint was life threatening cardiac events comprised of SCD or Aborted Cardiac Arrest (ACA). The secondary end point was syncope. Event rates per year were calculated and compared before and after LCSD.
Results: The mean±SD follow up time post LCSD was 14±9 years. The mean±SD age at the time of LCSD was 20±12 years. The mean±SD QTc was 525±68 msec. The event rate per year for ACA was 1.30 prior to LCSD and 0.33 post LCSD (p<.001). The event rate per year for syncope was 9.94 prior to LCSD and 2.83 post LCSD (p<.001). Importantly, Kaplan Meier estimates showed that twenty years post LCSD 29% of the patients had ACA/SCD and 45% had syncope.
Conclusions: In high risk LQTS patients who had BB treatment failure LCSD is effective in reducing the risk for SCD/ACA and syncope. Nevertheless, in the long term about a third of the patients will experience life threatening cardiac event and therefore LCSD should only be used in conjunction with implantable cardioverter defibrillator for the prevention of SCD.