Acute effects of energy drink consumption on left and right ventricular function - a 2-dimensional speckle tracking echocardiographic study.

Aim    Energy drinks (ED) contain high levels of caffeine and taurine and are associated with several cardiovascular effects. We investigated acute effects of consuming low caffeine and taurine content ED on left ventricular (LV) and right ventricular (RV) function assessed by conventional and two-dimensional speckle tracking echocardiography.Material and methods    In this crossover study, 34 healthy adults, age 19-48 yrs, drank an ED containing 53.25 milligrams of caffeine, 284 mg of taurine, or an equal volume of control drink (CD) on two separate sessions, 7-10 days apart. Standard echocardiographic and speckle tracking imaging were performed before and 60 min after consumption of the study beverages.Results    Compared to CD, ED caused a significant increase in tricuspid annular plane systolic excursion (p=0.04) and RV systolic wave velocity (p=0.01) with no effect on global longitudinal strain when compared to CD. LV systolic function was not altered, but mitral early diastolic velocity by tissue Doppler imaging was significantly higher (p=0.031), and early diastolic strain rate, as measured by speckle tracking echocardiography, was significantly lower (p=0.022).Conclusion    Reduced caffeine and taurine content ED does not affect LV systolic function, but increases RV longitudinal contractility and improves LV early diastolic filling.

Acute effects of consumption of low-caffeine energy drinks on endothelial functions in healthy volunteers.

OBJECTIVE: Energy drink consumption is increasing among the population, especially adolescents and young adults. The health effects of energy drinks are unknown. In this study, we investigate the effects of low caffeine energy drinks on endothelial functions assessed by flow-mediated dilation (FMD) of the brachial artery. METHODS: Thirty healthy volunteers (15 men, 15 women) aged 19 to 46 years participated in the study. Flow-mediated dilation measurements of the brachial artery were performed and recorded per protocol. The volunteers were asked to drink 355 mL of energy drink containing 53.25 mg of caffeine after baseline measurements, and all measurements were repeated 60 minutes later. Baseline and post-energy drink values were compared. RESULTS: Systolic blood pressure (p=0.592), diastolic blood pressure (p=0.714), and heart rate values (p=0.056) were similar before and after the consumption of energy drinks. Preocclusion arterial diameters (p=0.236) and blood velocities (p=0.447) did not change after energy drink consumption. FMD levels were 9.2%±4.6% and 8.1%±4.7%, respectively, before and after energy drink consumption (p=0.176). Women had a 3% increase in preocclusion arterial diameters after energy drink consumption, whereas men had a 2.6% decrease (p=0.026) Conclusion: Low caffeine energy drinks containing 53.25 mg of caffeine/355 mL can did not have any influence on blood pressure, heart rate, or endothelial functions in healthy volunteers.