Competitive Sports Participation in Athletes With Congenital Long QT Syndrome

To the Editor: Competitive sports participation for athletes with long QT syndrome (LQTS) is guided by the 36th Bethesda Conference, which recommends that patients with either (1) symptoms, (2) a corrected QT interval (QTc) greater than 470 milliseconds (males) or 480 milliseconds (females), or (3) an implantable cardioverter-defibrillator (ICD) not participate in most sports. The European Society of Cardiology guidelines are more restrictive, disqualifying athletes from all sports based solely on a stringent QTc cutoff ( 440 milliseconds in males, 460 milliseconds in females). We sought to determine the outcomes of patients with LQTS who chose to remain athletes against guideline recommendations. Methods. In this institutional review board–approved study (with waiver of consent), we reviewed records for patients with LQT1-3 genotypes, aged 6 to 40 years, who were first evaluated in the Mayo Clinic LQTS Clinic between July 2000 and November 2010. Records were reviewed for athletic participation after LQTS diagnosis and LQTS-related events during a mean (SD) follow-up of 5.1 (2.9) years. No patients were lost to follow-up. All were reevaluated or contacted by phone after July 1, 2011. A “competitive athlete” was defined as one participating in organized competitive sports at the little league, middle or high school, collegiate, or professional level. The approach in the Mayo Clinic LQTS Clinic is to provide the athlete and their family with sufficient information to enable an informed decision regarding sports continuation. All patients received a comprehensive 2to 3-day clinical and genetic evaluation, including a 1to 2-hour consultation with an LQTS specialist (M.J.A.) and additional consultations as needed. Extensive counseling was provided to discuss individual prognosis and athletic participation guidelines. If a minor, the athlete and both parents had to agree to sports continuation. Tailored therapy included -blockers, left cardiac sympathetic denervation, an ICD, or a combination. QT drug avoidance, electrolyte and hydration replenishment, and minimization of core body temperature elevations were advised. Each athlete obtained an automatic external defibrillator as part of the sports gear, and relevant school officials and coaches were informed. Statistical analysis was performed using JMP version 8.0 (SAS Institute). A 2-tailed P .05 was considered significant. Results. Of 353 LQT1-3 patients (199 females; mean [SD] age, 17 [11] years; mean [SD] QTc, 472 [42] milliseconds), the majority (223, 63%) either were not involved in sports (196, 88%) or chose to discontinue sports (27, 12%) following evaluation. Overall, 130 patients (37%, 60 females; age, 11 [7] years; QTc, 471 [46] milliseconds) remained in competitive athletics, including 20 with ICDs. There were no significant differences between the total cohort and athletes except that the nonathletes were older (TABLE). The 130 athletes competed in a variety of competitive sports (FIGURE), and 49 of 130 (38%) participated in more than 1 sport. There were 32 athletes (25%) competing in high school and 8 (6%) competing at the college, university, or professional level. Seventy athletes (54%) were competing contrary to European guidelines but within Bethesda guidelines. None had a sport-related event. Of the 60 LQTS athletes (46%) continuing in sports contrary to both guidelines, only 1 experienced sporting-related events: a 9-year-old boy with LQT1, extreme QT prolongation (QTc 550 milliseconds), and a history of aborted cardiac arrest. He received 2 appropriate ventricular fibrillation-terminating ICD shocks, both while warming up before games. Each episode occurred in the setting of admitted -blocker nonadherence. The overall rate of events per athlete-year was 0.003 (1 event in 331 athlete-years; 95% CI, 1 in 92 to 1 in 2763 athlete-years). Comment. Although many individuals with LQTS will choose to remain in competitive sports, athletes and their families are capable of self-disqualification. With more than 650 athlete-years of follow-up, we report a low rate of LQTStriggered cardiac events during sports. Limitations include the small sample size, limited length of follow-up, and unknown generalizability.