Long QT syndrome patients can do vigorous exercise without excess risk of cardiac events: Study

A new study by Rachel Lampert and team found that patients with long QT syndrome could engage in strenuous activity without developing an excess of cardiac events. The findings of this study were published in the journal of Circulation. It is uncertain if ventricular arrhythmias are more likely to occur in people with congenital long-QT syndrome (LQTS) who are receiving treatment. Thus, this study was to determine if intense exercise had an effect on the ventricular arrhythmias of people with long QT.

From May 2015 to February 2019, the participants with phenotypic or genotypic LQTS from 37 locations across five countries were prospectively enrolled in the LIVE-LQTS research (Lifestyle and Exercise in Genetic Cardiovascular Conditions), which was supported by the National Institutes of Health. For 3 years, participants (or their parents) responded to questionnaires on clinical occurrences and physical activity every six months. The follow-up was finished in February 2022. Over 60 hours a year at ≥6 metabolic equivalents was considered vigorous exercise. The composite end point of sudden cardiac arrest, sudden death, ventricular arrhythmia treated with an implanted cardioverter defibrillator, and probably arrhythmic syncope was determined by a blinded Clinical Events Committee. For people with insufficient follow-up, vital status was determined by a search of the National Death Index.

Of the 1413 participants, 13% were under the age of 18, 25% were between the ages of 18 and 25, 67% of the study cohort were female. Also, 25% had implanted cardioverter defibrillators, 90% were genotype positive, and 49% had LQT1 where 91% received treatment with beta-blockers, left cardiac sympathetic denervation, or implanted cardioverter defibrillators. 52% of the participants were engaged in vigorous exercise, 50% of which was competitive.

The composite end goal was encountered by 37 people and the total event rates at 3 years were 2.6% in the vigorous group and 2.7% in the non vigorous exercise groups. When comparing the vigorous group to the non vigorous group, the initial hazard ratio for event experience was 0.97 (90% CI, 0.57–1.67), whereas the adjusted hazard ratio was 1.17 (90% CI, 0.67–2.04). In any group or subgroup, neither strenuous nor non vigorous exercise was found to be superior. Overall, the people with phenotypic or genotypic LQTS who were risk assessed and treated at experienced institutions had low rates of LQTS-related cardiac events.

Reference:

Lampert, R., Day, S., Ainsworth, B., Burg, M., Marino, B. S., Salberg, L., Tome Esteban, M. T., Abrams, D. J., Aziz, P. F., Barth, C., Behr, E. R., Bell, C., Berul, C. I., Bos, J. M., Bradley, D., Cannom, D. S., Cannon, B. C., Concannon, M. A., Cerrone, M., … Ackerman, M. J. (2024). Vigorous Exercise in Patients With Congenital Long-QT Syndrome: Results of the Prospective, Observational, Multinational LIVE-LQTS Study. In Circulation. Ovid Technologies (Wolters Kluwer Health). https://doi.org/10.1161/circulationaha.123.067590