Abstract and Introduction
Aims: Sports practice, especially in competition, is usually restrained in patients diagnosed with long QT syndrome (LQTS). Although data are scarce, a low incidence of cardiac arrhythmic events (CAEs) during sports practice is reported. We aim to evaluate the incidence of CAE during sports practice in LQTS patients.
Methods and Results: All consecutive patients above 18 years of age diagnosed with LQTS and prospectively followed at the referral centre for inherited arrhythmia syndrome received a survey to retrospectively assess their sports practice prior to and after the diagnosis of LQTS. Two hundred and forty-six patients were included (57% females). The median age was 43 years, and the median QTc was 457 ms (428; 482). Patients reported a total of 4092 years [1376 (34%) after diagnosis] of sports practice: 2905 (77%) [1138 (39%) after diagnosis] years of leisure practice and 1187 (23%) [238 (20%) after diagnosis] years of competitive practice. One hundred and eighty (73%) patients practiced sport prior to the diagnosis of LQTS and 170 (69%) after. Prior to the diagnosis, four (2%) patients presented a CAE during leisure sports practice and one during competition. After diagnosis, only one patient presented a CAE, appropriately treated by an implantable cardioverter defibrillator discharge, in the context of beta-blocker non-compliance. The CAE event rate was 0.0007 events/year in the 1376 years of total sports practice after the diagnosis of LQTS.
Conclusion: After the diagnosis of LQTS, the occurrence of CAE is very low during sports practice, even in competitive practice. There was no CAE in patients properly treated with beta-blocker therapy with good compliance.
Overview of cardiac arrhythmic events according to sport practice among Long QT syndrome patients.
Long QT syndrome (LQTS) is an inherited arrhythmia syndrome, defined by a prolonged QT interval on the surface electrocardiogram (ECG), with no underlying structural heart disease or acute disorders prolonging the QT interval. Long QT syndrome can cause life-threatening ventricular arrhythmia and sudden death. Mutations in genes encoding for cardiac ion channels are responsible for most cases with LQTS. Three major genes are involved: KCNQ1 for LQT1, KCNH2 for LQT2, and SCN5A for LQT3.
Triggers of these cardiac arrhythmic events (CAEs) usually differ according to the gene involved. In LQT1 patients, 62% of CAE occurred during exercise, especially swimming, whereas only 3% occurred at rest. In LQT2 patients, although <20% of CAE directly occurred at exercise, an adrenergic-mediated stimulus is often identified, including emotional stress in 43% of CAE. In LQT3, most of the CAEs occurred at rest (39%). The large predominance of LQT1 and LQT2 forms among LQTS have led to significant restrictions in sports practice among LQTS patients.
In 2013, the first study to focus on sports practice in North American athletes showed a very low rate (0.003 event/year of sports practice) of CAE. These results were confirmed by two later studies.[4,5] Whereas most sports were discouraged in all LQTS patients in the 2005 guidelines, the following guidelines became progressively more permissive. The latest North American guidelines published in 2015 did not restrict competitive sports in genotype-positive–phenotype-negative patients, except for swimming in LQT1 patients. On the contrary, the latest European guidelines recommended a shared decision in genotype-positive–phenotype-negative patients and did not allow high-intensity sport (leisure or competition), even under beta-blocker therapy, in patients with genotype-positive–phenotype-positive and a prolonged QTc interval >500 ms or with a past history of syncope or cardiac arrest.
This higher level of restriction in Europe may be explained by the need for physicians to certify that there is no contraindication to sports practice, while in the USA, simple counselling is acceptable. In this distinct legal context, the lack of European data may also explain the higher level of restriction. However, sport restrictions, especially in the young, may have strong social and psychological impacts, as well as long-term cardiovascular effects.[9–11]
Herein, we aim to provide the first European study concerning the safety of sports practice in a large cohort of patients diagnosed with LQTS.
Europace. 2022;24(10):1675-1683. © 2022 Oxford University Press
Copyright 2007 European Heart Rhythm Association of the European Society of Cardiology (ESC). Published by Oxford University Press. All rights reserved.