Browsing by Author "Greenshields, Joel T."

Now showing 1 - 3 of 3
  • Thumbnail Image
    Item
    Arterial stiffness is not acutely modified by consumption of a caffeinated soft drink sweetened with high‐fructose corn syrup in young healthy adults
    (Wiley, 2021) Freemas, Jessica A.; Greenshields, Joel T.; Baker, Tyler; Carter, Stephen J.; Johnson, Blair D.; Schlader, Zachary J.; Medicine, School of Medicine
    We tested the hypothesis that ingestion of a caffeinated soft drink sweetened with high-fructose corn syrup acutely increases arterial stiffness. In a randomized counterbalanced, crossover design, fourteen healthy adults (25 ± 3 years, 6 women) reported to the laboratory for two experimental visits where 500 ml of tap water (H2 O) or 500 ml of Mountain Dew® (a caffeinated soft drink sweetened with high-fructose corn syrup (HFCS)) were consumed. Arterial stiffness (carotid-to-femoral pulse wave velocity (cfPWV)), peripheral and central blood pressures were measured pre-consumption, 30 min post-consumption, and 120 min post-consumption. Prior to each measurement period, beat-to-beat hemodynamic measures were collected. Changes in heart rate, blood pressure, and cardiac output from pre-consumption did not differ between trials at any timepoint (p ≥ 0.06). Moreover, changes in peripheral or central blood pressures from pre-consumption did not differ between trials (p ≥ 0.84). Likewise, changes in cfPWV from pre-consumption to 30 min post-consumption (HFCS: 0.2 ± 0.3 m/s, H2 O: 0.0 ± 0.3 m/s, p = 0.34) and 120 min post-consumption (HFCS: 0.3 ± 0.4 m/s, H2 O: 0.2 ± 0.3 m/s, p = 0.77) did not differ. Changes in aortic augmentation pressure, augmentation index, augmentation index corrected to a heart rate of 75 bpm, and reflection magnitude did not differ between conditions at 30 min post- (p ≥ 0.55) or 120 min post- (p ≥ 0.18) consumption. In healthy young adults, ingesting 500 ml of a commercially available caffeinated soft drink sweetened with high-fructose corn syrup does not acutely change indices of arterial stiffness and wave reflection.
  • Thumbnail Image
    Item
    Cutaneous microvascular vasodilatory consequences of acute consumption of a caffeinated soft drink sweetened with high‐fructose corn syrup
    (Wiley, 2021) Greenshields, Joel T.; Keeler, Jason M.; Freemas, Jessica A.; Baker, Tyler B.; Johnson, Blair D.; Carter, Stephen J.; Schlader, Zachary J.; Medicine, School of Medicine
    This study tested the hypotheses that compared to drinking water, consumption of a caffeinated soft drink sweetened with high-fructose corn syrup (HFCS) attenuates the cutaneous vasodilatory response to local skin heating without (Protocol 1) and following ischemia-reperfusion injury (Protocol 2). In a randomized, counterbalanced crossover design, 14 healthy adults (25 ± 3 year, 6 women) consumed 500 ml of water (water) or a caffeinated soft drink sweetened with HFCS (Mtn. Dew, DEW). Thirty minutes following beverage consumption local skin heating commenced on the right forearm (Protocol 1), while on the left forearm ischemia-reperfusion commenced with 20 min of ischemia followed by 20 min of reperfusion and then local skin heating (Protocol 2). Local skin heating involved 40 min of heating to 39℃ followed by 20 min of heating to 44℃. Skin blood flow (SkBf, laser Doppler) data were normalized to mean arterial pressure and are presented as a cutaneous vascular conductance (CVC) and as percentage of the CVC response during heating to 44℃ (%CVCmax ). Protocol 1: During local heating at 39℃, no differences were observed in CVC (water: 2.0 ± 0.6 PU/mmHg; DEW: 2.0 ± 0.8 PU/mmHg, p = 0.83) or %CVCmax (water: 59 ± 14%; DEW 60 ± 15%, p = 0.84) between trials. Protocol 2: During local skin heating at 39℃, no differences were observed in CVC (water: 1.7 ± 0.5 PU/mmHg; DEW: 1.5 ± 0.5 PU/mmHg, p = 0.33) or %CVCmax (water: 64 ± 15%; DEW 61 ± 15% p = 0.62) between trials. The cutaneous microvascular vasodilator response to local heating with or without prior ischemia-reperfusion injury is not affected by acute consumption of a caffeinated soft drink sweetened with HFCS.
  • Thumbnail Image
    Item
    Prevalence of Clinical and Subclinical Myocarditis in Competitive Athletes With Recent SARS-CoV-2 Infection: Results From the Big Ten COVID-19 Cardiac Registry
    (AMA, 2021-05-27) Daniels, Curt J.; Rajpal, Saurabh; Greenshields, Joel T.; Rosenthal, Geoffrey L.; Chung, Eugene H.; Terrin, Michael; Jeudy, Jean; Mattson, Scott E.; Law, Ian H.; Borchers, James; Kovacs, Richard; Kovan, Jeffrey; Rifat, Sami F.; Albrecht, Jennifer; Bento, Ana I.; Albers, Lonnie; Bernhardt, David; Day, Carly; Hecht, Suzanne; Hipskind, Andrew; Mjaanes, Jeffrey; Olson, David; Rooks, Yvette L.; Somers, Emily C.; Tong, Matthew S.; Wisinski, Jeffrey; Womack, Jason; Esopenko, Carrie; Kratochvil, Christopher J.; Rink, Lawrence D.; Medicine, School of Medicine
    Importance: Myocarditis is a leading cause of sudden death in competitive athletes. Myocardial inflammation is known to occur with SARS-CoV-2. Different screening approaches for detection of myocarditis have been reported. The Big Ten Conference requires comprehensive cardiac testing including cardiac magnetic resonance (CMR) imaging for all athletes with COVID-19, allowing comparison of screening approaches. Objective: To determine the prevalence of myocarditis in athletes with COVID-19 and compare screening strategies for safe return to play. Design, Setting, and Participants: Big Ten COVID-19 Cardiac Registry principal investigators were surveyed for aggregate observational data from March 1, 2020, through December 15, 2020, on athletes with COVID-19. For athletes with myocarditis, presence of cardiac symptoms and details of cardiac testing were recorded. Myocarditis was categorized as clinical or subclinical based on the presence of cardiac symptoms and CMR findings. Subclinical myocarditis classified as probable or possible myocarditis based on other testing abnormalities. Myocarditis prevalence across universities was determined. The utility of different screening strategies was evaluated. Exposures: SARS-CoV-2 by polymerase chain reaction testing. Main Outcome and Measure: Myocarditis via cardiovascular diagnostic testing. Results: Representing 13 universities, cardiovascular testing was performed in 1597 athletes (964 men [60.4%]). Thirty-seven (including 27 men) were diagnosed with COVID-19 myocarditis (overall 2.3%; range per program, 0%-7.6%); 9 had clinical myocarditis and 28 had subclinical myocarditis. If cardiac testing was based on cardiac symptoms alone, only 5 athletes would have been detected (detected prevalence, 0.31%). Cardiac magnetic resonance imaging for all athletes yielded a 7.4-fold increase in detection of myocarditis (clinical and subclinical). Follow-up CMR imaging performed in 27 (73.0%) demonstrated resolution of T2 elevation in all (100%) and late gadolinium enhancement in 11 (40.7%). Conclusions and Relevance: In this cohort study of 1597 US competitive athletes with CMR screening after COVID-19 infection, 37 athletes (2.3%) were diagnosed with clinical and subclinical myocarditis. Variability was observed in prevalence across universities, and testing protocols were closely tied to the detection of myocarditis. Variable ascertainment and unknown implications of CMR findings underscore the need for standardized timing and interpretation of cardiac testing. These unique CMR imaging data provide a more complete understanding of the prevalence of clinical and subclinical myocarditis in college athletes after COVID-19 infection. The role of CMR in routine screening for athletes safe return to play should be explored further.