Abstract 12640: Energy Drinks Prolong Early Repolarization (J-T
Peak
) Phase in a Healthy Population
Introduction: Energy drinks continue to be the fastest growing beverage market with sales expected to reach $60 billion in the next few years, yet have demonstrated adverse cardiovascular effects such as prolongation of the QTc interval on EKG. While QTc prolongation observed with certain drugs has long been used as an indicator of increased risk of torsade de pointes, recent data has identified the early repolarization interval J-T peak (JTp) as a more specific marker for proarrhythmic potential. Drugs that selectively block the human ether-a-go-go related (hERG) potassium ion channel prolong QTc by prolonging both early repolarization (JTp) and late repolarization (T peak -T end [Tpe] interval), and are associated with an increased risk of torsade. In contrast, drugs that additionally block inward late sodium and L-type calcium prolong QTc by prolonging Tpe but not JTp, and have demonstrated reduced risk of torsade. In 2018, the C-Energy-X study demonstrated QTc prolongation in 22 healthy subjects (mean age 28 ± 7yrs) who consumed energy drink while at rest and following short periods of exercise. Our study provides a secondary analysis of this data in terms of its effect on JTp, a potentially more specific marker for torsade risk. Methods: Using H-Scribe software, two evaluators independently measured JTp and RR intervals from C-Energy-X subjects pre- and post-energy drink consumption in the rest and exercise phases. Values were corrected for heart rate using the linear correction formula JTpc=JTp + 0.150(1-RR), where RR is R-to-R interval. Mean JTpc values from each phase were analyzed using a paired sample two-tailed t -test. Results: In the resting phase following energy drink consumption (PCr), there was a statistically significant increase in JTpc intervals for 77% of subjects by a mean of 10.5ms (baseline=234 ± 21.3ms; PCr=245 ± 22.0ms; p =0.015). In the exercise phase following energy drink consumption (PCe), 64% of subjects increased JTpc intervals by a mean of 0.8ms which was not significant (baseline=225 ± 15.7ms; PCe=226 ± 17.9ms; p =0.845). Conclusion: In the resting phase, energy drink consumption was associated with statistically significant prolongation of JTpc, suggesting a theoretical increased risk of torsade de pointes.