Contemporary Outcomes in Patients With Long QT Syndrome

Ram K. Rohatgi, Alan Sugrue, J. Martijn Bos, Bryan C. Cannon, Samuel J. Asirvatham, Christopher Moir, Heidi J. Owen, Katy M. Bos, Teresa Kruisselbrink, Michael J. Ackerman

Research output: Contribution to journalArticlepeer-review

36 Scopus citations

Abstract

Background Long QT syndrome (LQTS) is a potentially lethal cardiac channelopathy with a 1% to 5% annual risk of LQTS-triggered syncope, aborted cardiac arrest, or sudden cardiac death. Objectives This study sought to evaluate LQTS outcomes from a single center in the contemporary era. Methods The authors conducted a retrospective study comprising the 606 patients with LQTS (LQT1 in 47%, LQT2 in 34%, and LQT3 in 9%) who were evaluated in Mayo Clinic's Genetic Heart Rhythm Clinic from January 1999 to December 2015. Breakthrough cardiac events (BCEs) were defined as LQTS-attributable syncope or seizures, aborted cardiac arrest, appropriate ventricular fibrillation–terminating implantable cardioverter-defibrillator shocks, and sudden cardiac death. Results There were 166 (27%) patients who were symptomatic prior to their first Mayo Clinic evaluation. Median age at first symptom was 12 years. Treatment strategies included no active therapy in 47 (8%) patients, beta-blockers alone in 350 (58%) patients, implantable cardioverter-defibrillators alone in 25 (4%) patients, left cardiac sympathetic denervation alone in 18 (3%) patients, and combination therapy in 166 (27%) patients. Over a median follow-up of 6.7 (IQR: 3.9 to 9.8) years, 556 (92%) patients have not experienced an LQTS-triggered BCE. Only 8 of 440 (2%) previously asymptomatic patients have experienced a single BCE. In contrast, 42 of 166 (25%) previously symptomatic patients have experienced ≥1 BCE. Among the 30 patients with ≥2 BCEs, 2 patients have died and 3 LQT3 patients underwent cardiac transplantation. Conclusions Although outcomes have improved markedly, further optimization of treatment strategies is still needed given that 1 in 4 previously symptomatic patients experienced at least 1 subsequent, albeit nonlethal, LQTS-triggered cardiac event.

Original languageEnglish (US)
Pages (from-to)453-462
Number of pages10
JournalJournal of the American College of Cardiology
Volume70
Issue number4
DOIs
StatePublished - Jul 25 2017

Keywords

  • LQTS
  • breakthrough cardiac events
  • genetics
  • long QT syndrome
  • outcomes

ASJC Scopus subject areas

  • Cardiology and Cardiovascular Medicine

Fingerprint Dive into the research topics of 'Contemporary Outcomes in Patients With Long QT Syndrome'. Together they form a unique fingerprint.

Cite this