Evaluation and Management of Athletes With Long QT Syndrome

Abstract

Context:The congenital long QT syndrome (LQTS) is an inherited channelopathy known for its electrocardiographic manifestations of QT prolongation and its hallmark arrhythmia, torsades de pointes (TdP). TdP can lead to syncope or sudden death and is often precipitated by triggers such as physical exertion or emotional stress. Given that athletes may be at particular risk for adverse outcomes, those suspected of having LQTS should be evaluated, risk stratified, treated, and receive appropriate counseling by providers with sufficient expertise according to the latest guidelines.Evidence Acquisition:The following keywords were used to query MEDLINE and PubMed through 2016: LQTS, LQT1, LQT2, LQT3, long QT, long QTc, prolonged QT, prolonged QTc, QT interval, QTc interval, channelopathy, channelopathies, athletes, torsades de pointes, and sudden cardiac death. Selected articles within this primary search, in addition to relevant references from those articles, were reviewed for relevant information and data. Articles with pertinent information regarding pathophysiology, evaluation, diagnosis, genetic testing, treatment, and guidelines for athletes were included, particularly those published in the prior 2 decades.Study Design:Clinical review.Level of Evidence:Level 3.Results:Diagnosis of LQTS involves eliciting the patient’s family history, clinical history, and evaluation of electrocardiographic findings. Genetic testing for common mutations can confirm suspected cases. β-Blockers represent the mainstay of treatment, though interventions such as implantable cardioverter-defibrillator placement or left cardiac sympathetic denervation may be required. Properly evaluated and treated athletes with LQTS have a low risk of cardiac events.Conclusion:Detection and management of LQTS in the athletic population is crucial given the possibility of adverse outcomes with the stress of athletic participation. Preparticipation screening examinations should include a thorough clinical and family history. Screening electrocardiograms may display key findings consistent with LQTS while genetic testing can confirm the diagnosis. Formerly considered a strict contraindication to athletic participation, LQTS is now an increasingly manageable entity with proper evaluation and treatment by qualified and experienced providers.

Clinical Genetics of Inherited Arrhythmogenic Disease in the Pediatric Population

“…The copy number variants (CNV) detection rate among LQTS families is not very clear, but is estimated to be between 2–11% [ 134 , 135 , 136 , 137 , 138 ]. Population screening by ECG has been promoted to identify individuals at risk of LQTS, which has been successful in reducing SCD rates among patient family members [ 139 ] neonates [ 27 , 140 ] and athletes [ 141 , 142 ].…”

The correlation of blood pressure changes and cardiac morpho- functional restructuring in young athletes

“…У одного из спортсменов, имевшего патологическое ремоделирование миокарда (гипертрофия миокарда левого желудочка, избыточная реакция артериального давления на пробу с дозированной физической нагрузкой), было выявлено пограничное удлинение интервала QTс, не связанное с заменами в гене NOS1. Замедление реполяризации у данного атлета могло быть обусловлено как другими генетическими полиморфизмами, так и вторичными причинами -развитием гипертрофии миокарда левого желудочка, нейрогуморальными, электролитными сдвигами или их сочетанием [22].…”

QT Prolongation and Malignant Arrhythmia: How Serious a Problem?

“…47 More specifically, in the case of congenital long QT syndrome type 1 and 2, beta-blockers constitute the recommended initial approach to all patients in the absence of contraindications, such as asthma. 6,52,53 They have been shown to reduce event rates by as much as 81 % and 59 %, respectively, 54 and most of residual events are often due to non-adherence to the regimens. 55 Beta-blockers do not themselves shorten the QT interval, rather, they abrogate the prolonging effects of increased heart rate on it.…”

“…A pacemaker may be used in those with acquired, pause-dependent forms of the syndrome, or in those with type 3 congenital long QT that exhibit similar susceptibility to arrhythmia during bradycardia. 52 Obviously, both pacemakers and isoproterenol infusion…”