Return-to-Play for Athletes With Long QT Syndrome or Genetic Heart Diseases Predisposing to Sudden Death

Return-to-Play for Athletes With Long QT Syndrome or Genetic Heart Diseases Predisposing to Sudden Death.

Tobert KE, Bos JM, Garmany R, Ackerman MJ.

J Am Coll Cardiol. 2021 Aug 10;78(6):594-604. doi: 10.1016/j.jacc.2021.04.026.PMID: 34330632


Take Home Points

  • Current international guidelines for athletes with sudden cardiac death-predisposing genetic heart diseases (GHD) recommend disqualification from competitive sport to mitigate the potential risk of malignant arrhythmia – “if in doubt, kick them out”.
  • This retrospective study examined the prevalence and outcome of athletes with sudden cardiac death-GHDs after their return to sport. The primary analysis focused on patients with LQTS.
  • This was a single center study spanning 2 decades (2000-2020) of all athletes with GHD whom had been given return-to-play approval and whom had been reviewed at the Mayo Clinic’s Windland Smith Rice Genetic Heart Rhythm Clinic.
  • 672 athletes had GHD, of whom 494 had LQTS. Mean age at diagnosis 14.8 +/- 10.5 years with a mean FU of 4.2 +/- 4.8 years.
  • In 2056 combined years of follow up, there were no GHD-sports associated mortality.
  • 29 patients (5.9%) had > 1 non-lethal, LQTS-associated breakthrough cardiac event. Of those, 15 patients were athletes at the time of the breakthrough event with only 3 experiencing a sports-related breakthrough cardiac event, and 12 a non-sports-related event.
  • Breakthrough cardiac events in athletes returning to sport were rare, which challenges the present convention of mandated disqualification.
  • All athletes had been reviewed by a highly proficient and experienced inherited cardiac conditions team and all patients participated in a shared decision-making process before being given approval to return to play.

Dr Damien Cullington




Commentary from Dr. Damien Cullington (Liverpool, UK), section editor of ACHD Journal Watch:

Each year, 1 in 50,000 – 1 in 80,000 athletes experience sudden cardiac death (SCD). The etiology for often tragic demise is broad but the commonest causes are often due to underlying genetic heart diseases e.g., long QT syndrome, hypertrophic cardiomyopathy and arrhythmogenic cardiomyopathy. LQTS is found in 1 in 2000 people. There are ever increasing numbers of gene variants but the commonest 3 genetic aberrations affecting KCNQ1, KCNH2 and SCN5A account for up to 80% of all LQTS.

The prevailing mindset is that exercise in individuals with LQTS is hazardous and therefore participation in competitive sport is contra-indicated. International guidelines recommend disqualification from essentially all competitive sports for any phenotype positive athlete with a GHD. Some patients are genotype positive but phenotype negative – perhaps this subset of patients pose a lower risk of arrhythmic complications if they return to play (RTP).


Return to play (RTP) and Patient Cohort.


All patients analyzed in this retrospective analysis had been through a rigorous assessment to RTP (Figure 1). The demographics of the patient cohort used for the analysis are shown in Table 1.


Figure 1 – RTP Protocol and Outcomes for Patients with LQTS


Table 1 – Cohort Demographics


Breakthrough cardiac events (BCEs) were defined as arrhythmogenic syncope or seizures, symptomatic non-sustained VT, an appropriate VT and/or VF terminating therapy from an ICD, sudden cardiac arrest with defibrillator rescue, or sudden cardiac death. Figure 2 summarizes events. Of 494 athletes with LQTS, there were 2 deaths but, both were unrelated to the athlete’s LQTS diagnosis. Amazingly, over a 20 year period, there were no deaths due to LQTS whatsoever. 94% of athletes (n=465) did not experience any LQTS related BCEs. 39 athletes (5.9%) had > 1 BCE during follow up – but only 15 patients experienced this in their RTP period.


No observed difference was seen in the risk of events during the RTP period between different LQTS genotypes (p=0.41) (Figure 3). Sporting type was not associated with BCEs (Figure 4).


Figure 2 – Summary of BCEs


Figure 3 – BCEs divided by LQTS subtypes


Figure 4



  • Single center study by an expert inherited cardiac conditions team – generalizability of the excellent outcomes may be difficult to emulate.
  • Half of patients assessed attended only once and then returned to their parent cardiologist – it is possible BCEs may have occurred without being recorded in the study.
  • Depending on geographic location of the athlete, irrespective of the promising results of this analysis, and adoption of the RTP protocol, participation in sport and RTP may still be precluded.


  • This is the largest LQTS cohort RTP with a combined FU of 2057 years (including 1287 athlete years of FU).
  • It is possible for athletes to RTP if assessed and managed expertly according to a comprehensive protocol.
  • Current international guidelines give blanket advice to stop competitive sport.
  • This study challenges convention – with expert management as part of a shared decision-making process there is no absolute requirement to apply blanket cessation advice to all athletes with LQTS and low rates of BCEs are observed in athletes who RTP.