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American Journal of Physiology. Heart... Sep 2020Tobacco cigarette (TC) smoking has never been lower in the United States, but electronic cigarette (EC) vaping has reached epidemic proportions among our youth.... (Comparative Study)
Comparative Study
Tobacco cigarette (TC) smoking has never been lower in the United States, but electronic cigarette (EC) vaping has reached epidemic proportions among our youth. Endothelial dysfunction, as measured by flow-mediated vasodilation (FMD) is a predictor of future atherosclerosis and adverse cardiovascular events and is impaired in young TC smokers, but whether FMD is also reduced in young EC vapers is uncertain. The aim of this study in otherwise healthy young people was to compare the effects of acute and chronic tobacco cigarette (TC) smoking and electronic cigarette (EC) vaping on FMD. FMD was compared in 47 nonsmokers (NS), 49 chronic EC vapers, and 40 chronic TC smokers at baseline and then after EC vapers ( = 31) and nonsmokers ( = 47) acutely used an EC with nicotine (ECN), EC without nicotine (EC0), and nicotine inhaler (NI) at ~4-wk intervals and after TC smokers ( = 33) acutely smoked a TC, compared with sham control. Mean age (NS, 26.3 ± 5.2 vs. EC, 27.4 ± 5.45 vs. TC, 27.1 ± 5.51 yr, = 0.53) was similar among the groups, but there were more female nonsmokers. Baseline FMD was not different among the groups (NS, 7.7 ± 4.5 vs. EC:6.6 ± 3.6 vs. TC, 7.9 ± 3.7%∆, = 0.35), even when compared by group and sex. Acute TC smoking versus control impaired FMD (FMD pre-/postsmoking, -2.52 ± 0.92 vs. 0.65 ± 0.93%∆, = 0.02). Although the increase in plasma nicotine was similar after EC vapers used the ECN versus TC smokers smoked the TC (5.75 ± 0.74 vs. 5.88 ± 0.69 ng/mL, = 0.47), acute EC vaping did not impair FMD. In otherwise healthy young people who regularly smoke TCs or ECs, impaired FMD compared with that in nonsmokers was not present at baseline. However, FMD was significantly impaired after smoking one TC, but not after vaping an equivalent "dose" (estimated by change in plasma nicotine) of an EC, consistent with the notion that non-nicotine constituents in TC smoke mediate the impairment. Although it is reassuring that acute EC vaping did not acutely impair FMD, it would be dangerous and premature to conclude that ECs do not lead to atherosclerosis. In our study of otherwise healthy young people, baseline flow-mediated dilation (FMD), a predictor of atherosclerosis and increased cardiovascular risk, was not different among tobacco cigarette (TC) smokers or electronic cigarette (EC) vapers who had refrained from smoking, compared with nonsmokers. However, acutely smoking one TC impaired FMD in smokers, whereas vaping a similar EC "dose" (as estimated by change in plasma nicotine levels) did not. Finally, although it is reassuring that acute EC vaping did not acutely impair FMD, it would be premature and dangerous to conclude that ECs do not lead to atherosclerosis or increase cardiovascular risk.
Topics: Adult; Atherosclerosis; Brachial Artery; Cigarette Smoking; Consumer Product Safety; Cross-Over Studies; E-Cigarette Vapor; Electronic Nicotine Delivery Systems; Endothelium, Vascular; Female; Healthy Volunteers; Humans; Male; Middle Aged; Random Allocation; Risk Assessment; Risk Factors; Vaping; Vasodilation; Young Adult
PubMed: 32734819
DOI: 10.1152/ajpheart.00307.2020 -
The American Journal of Sports Medicine Jul 2019Previous studies have shown that changing acutely from shod to barefoot running induces several changes to running biomechanics, such as altered ankle kinematics,... (Randomized Controlled Trial)
Randomized Controlled Trial
BACKGROUND
Previous studies have shown that changing acutely from shod to barefoot running induces several changes to running biomechanics, such as altered ankle kinematics, reduced ground-reaction forces, and reduced loading rates. However, uncertainty exists whether these effects still exist after a short period of barefoot running habituation.
PURPOSE/HYPOTHESIS
The purpose was to investigate the effects of a habituation to barefoot versus shod running on running biomechanics. It was hypothesized that a habituation to barefoot running would induce different adaptations of running kinetics and kinematics as compared with a habituation to cushioned footwear running or no habituation.
STUDY DESIGN
Controlled laboratory study.
METHODS
Young, physically active adults without experience in barefoot running were randomly allocated to a barefoot habituation group, a cushioned footwear group, or a passive control group. The 8-week intervention in the barefoot and footwear groups consisted of 15 minutes of treadmill running at 70% of VO max (maximal oxygen consumption) velocity per weekly session in the allocated footwear. Before and after the intervention period, a 3-dimensional biomechanical analysis for barefoot and shod running was conducted on an instrumented treadmill. The passive control group did not receive any intervention but was also tested prior to and after 8 weeks. Pre- to posttest changes in kinematics, kinetics, and spatiotemporal parameters were then analyzed with a mixed effects model.
RESULTS
Of the 60 included participants (51.7% female; mean ± SD age, 25.4 ± 3.3 years; body mass index, 22.6 ± 2.1 kg·m), 53 completed the study (19 in the barefoot habituation group, 18 in the shod habituation group, and 16 in the passive control group). Acutely, running barefoot versus shod influenced foot strike index and ankle, foot, and knee angles at ground contact ( < .001), as well as vertical average loading rate ( = .003), peak force ( < .001), contact time ( < .001), flight time ( < .001), step length ( < .001), and cadence ( < .001). No differences were found for average force ( = .391). After the barefoot habituation period, participants exhibited more anterior foot placement ( = .006) when running barefoot, while no changes were observed in the footwear condition. Furthermore, barefoot habituation increased the vertical average loading rates in both conditions (barefoot, = .01; shod, = .003) and average vertical ground-reaction forces for shod running ( = .039). All other outcomes (ankle, foot, and knee angles at ground contact and flight time, contact time, cadence, and peak forces) did not change significantly after the 8-week habituation.
CONCLUSION
Changing acutely from shod to barefoot running in a habitually shod population increased the foot strike index and reduced ground-reaction force and loading rates. After the habituation to barefoot running, the foot strike index was further increased, while the force and average loading rates also as compared with the acute barefoot running situation. The increased average loading rate is contradictory to other studies on acute adaptations of barefoot running.
CLINICAL RELEVANCE
A habituation to barefoot running led to increased vertical average loading rates. This finding was unexpected and questions the generalizability of acute adaptations to long-term barefoot running. Sports medicine professionals should consider these adaptations in their recommendations regarding barefoot running as a possible measure for running injury prevention.
REGISTRATION
DRKS00011073 (German Clinical Trial Register).
Topics: Adult; Ankle Joint; Biomechanical Phenomena; Body Mass Index; Exercise Test; Female; Foot; Gait; Humans; Kinetics; Knee Joint; Male; Prospective Studies; Running; Shoes; Single-Blind Method; Young Adult
PubMed: 31166116
DOI: 10.1177/0363546519849920 -
Cardiology Clinics Aug 2022The Coronavirus 2019 (COVID-19) pandemic, caused by the Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) virus, has resulted in unprecedented morbidity and... (Review)
Review
The Coronavirus 2019 (COVID-19) pandemic, caused by the Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) virus, has resulted in unprecedented morbidity and mortality worldwide. While COVID-19 typically presents as viral pneumonia, cardiovascular manifestations such as acute coronary syndromes, arterial and venous thrombosis, acutely decompensated heart failure (HF), and arrhythmia are frequently observed. Many of these complications are associated with poorer outcomes, including death. Herein we review the relationship between cardiovascular risk factors and outcomes among patients with COVID-19, cardiovascular manifestations of COVID-19, and cardiovascular complications associated with COVID-19 vaccination.
Topics: COVID-19; COVID-19 Vaccines; Cardiovascular Diseases; Humans; Pneumonia, Viral; SARS-CoV-2
PubMed: 35851451
DOI: 10.1016/j.ccl.2022.03.001 -
Heart Failure Clinics Apr 2023The Coronavirus 2019 (COVID-19) pandemic, caused by the Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) virus, has resulted in unprecedented morbidity and... (Review)
Review
The Coronavirus 2019 (COVID-19) pandemic, caused by the Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) virus, has resulted in unprecedented morbidity and mortality worldwide. While COVID-19 typically presents as viral pneumonia, cardiovascular manifestations such as acute coronary syndromes, arterial and venous thrombosis, acutely decompensated heart failure (HF), and arrhythmia are frequently observed. Many of these complications are associated with poorer outcomes, including death. Herein we review the relationship between cardiovascular risk factors and outcomes among patients with COVID-19, cardiovascular manifestations of COVID-19, and cardiovascular complications associated with COVID-19 vaccination.
Topics: Humans; COVID-19 Vaccines; COVID-19; SARS-CoV-2; Heart Failure; Pandemics
PubMed: 36863807
DOI: 10.1016/j.hfc.2022.08.001 -
Cureus Aug 2023Accurate determination of intravascular volume status is challenging in acutely ill patients. Favorable patient outcome is vital to correctly identify intravascular... (Review)
Review
Accurate determination of intravascular volume status is challenging in acutely ill patients. Favorable patient outcome is vital to correctly identify intravascular volume depletion and avoid systemic venous congestion. Most of the conventional means of hemodynamic monitoring in the acute healthcare setting are geared toward addressing the cardiac output and maintaining an optimum mean arterial pressure. While assessing and maintaining cardiac output in an acutely ill patient is very important, a venous congestion cascade is often overlooked, which can negatively affect the intraabdominal end organs. The prospect of using point-of-care ultrasound (POCUS) to determine systemic venous congestion could be a potentially handy tool for clinicians. Venous excess ultrasound score (VExUS) has also been utilized by clinicians as a semi-quantitative assessment tool to assess fluid status. This review aims to discuss the potential role of POCUS and VExUS scores in determining systemic venous congestion through a narrative review of recently published literature.
PubMed: 37724234
DOI: 10.7759/cureus.43716