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5.6.6 Brugada syndrome The Brugada syndrome (BrS) is an inherited cardiac ion channel disorder with an elevated risk of VF and SCD in individuals with a structurally normal heart.533,534 Although BrS was initially described as a purely electrical disease, minor structural RV abnormalities have been described,535538 suggesting that the disease may be the result of early repolarization or delayed depolarization.509 The diagnosis is based on the presence of the type 1 Brugada pattern on the 12-lead ECG (coved-type ST-segment elevation >_2 mm followed by a negative T-wave in >_1 mm of the right precordial leads positioned in the fourth, third, or second intercostal space), either spontaneously or following provocation by a sodium ion channel blocker.523,539,540 Most individuals with BrS remain asymptomatic throughout their lives. In the majority of cases, events occur during sleep or rest, during febrile states or, occasionally, from heat stroke.541549 Patients who have suffered a SCA or an arrhythmic syncope should undergo ICD implantation.247,511 Risk stratification in the asymptomatic population with spontaneous type 1 ECG pattern is more challenging.247,511 There is controversial evidence that exercise testing showing an aggravating phenotype during exercise or early recovery, or EP study, are efficient at detecting individuals at risk of SCD. In asymptomatic patients with only inducible type 1 Brugada ECG pattern, preventive measures are recommended, such as avoidance of triggering drugs (www.brugadadrugs.org), electrolyte imbalance, and increases in core temperature >39C (e.g. by minimizing immersion in hot tubs, saunas, and steam rooms; by avoiding sports in warm/humid conditions; or by abstaining from prolonged endurance events such as triathlons and marathons). During febrile illness, fever should be treated aggressively.247,511

One could speculate that an enhanced vagal reaction during recovery550 and a predominant vagal tone at rest551 may increase the susceptibility of highly trained individuals to develop arrhythmias during recovery or at rest. However, there are no reports directly linking exercise or sports training to cardiac events and there are no large prospective studies evaluating the effect of exercise and sports in BrS. Asymptomatic patients with the spontaneous type I BrS ECG pattern may compete in all sports except endurance sports associated with an increase in core temperature >39C (e.g. marathon running and triathlons). Similar rules apply to asymptomatic genotypepositive/phenotype-negative individuals and those with the concealed form of BrS. If treated with an ICD, provided precautionary measures are taken and the patient has been asymptomatic for >_3 months, resumption of all sport, including competitive sport, may be considered, after shared decision making, and also taking into consideration the findings from the ICD registry (see later).

Recommendations for exercise in long QT syndrome

Recommendations Classa Levelb

It is recommended that all exercising individuals with LQTS with prior symptoms or prolonged QTc be on therapy with beta-blockers at target dose.529 I B It is recommended that exercising individuals with LQTS should avoid QT prolonging drugs (www.crediblemeds.org) and electrolyte imbalance such as hypokalaemia and hypomagnesaemia.529 I B Shared decision making should be considered regarding sports participation in patients with genotype-positive/phenotype-negative LQTS (i.e. <470/480 ms in men/women). Type and setting of sports (individual vs. team), type of mutation, and extent of precautionary measures should be considered in this context. IIa C Participation in high-intensity recreational and competitive sports, even when on beta-blockers, is not recommended in individuals with a QTc>500 ms or a genetically confirmed LQTS with a QTc>_470 ms in men or >_480 ms in women. III B Participation in competitive sports (with or without ICD) is not recommended in individuals with LQTS and prior cardiac arrest or arrhythmic syncope. III C

ICD = implantable cardioverter defibrillator; LQTS = long QT syndrome. aClass of recommendation. bLevel of evidence. Recommendations for exercise in Brugada syndrome

Recommendations Classa Levelb

ICD implantation is recommended in patients with BrS with episodes of arrhythmic syncope and/or aborted SCD.247 I C Following implantation of an ICD, resumption of leisure or competitive sports should be considered after shared decision making in individuals who have not experienced recurrent arrhythmias over 3 months after ICD implantation. IIa C In asymptomatic individuals with BrS, asymptomatic mutation carriers and asymptomatic athletes with only an inducible ECG pattern, participation in sports activities that are not associated with an increase in core temperature >39C (e.g. endurance events under extremely hot and/or humid conditions) may be considered. IIb C Prescription of drugs that may aggravate BrSc, electrolyte abnormalities, and sports practice that increases core temperature >39

C are not

recommended in individuals with overt BrS or phenotypically negative mutation carriers. III C

BrS = Brugada syndrome; ECG = electrocardiogram; ICD = implantable cardioverter defibrillator; SCD = sudden cardiac death. aClass of recommendation. bLevel of evidence. cFor example, www.brugadadrugs.org. Downloaded from academic.oup.com/eurheartj/article/42/1/17/5898937 by guest on 07 October 2026