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1.
Am Fam Physician ; 104(2): 179-185, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-34383451

RESUMO

Sinus node dysfunction, previously known as sick sinus syndrome, describes disorders related to abnormal conduction and propagation of electrical impulses at the sinoatrial node. An abnormal atrial rate may result in the inability to meet physiologic demands, especially during periods of stress or physical activity. Sinus node dysfunction may occur at any age, but is usually more common in older persons. The causes of sinus node dysfunction are intrinsic (e.g., degenerative idiopathic fibrosis, cardiac remodeling) or extrinsic (e.g., medications, metabolic abnormalities) to the sinoatrial node. Many extrinsic causes are reversible. Electrocardiography findings include sinus bradycardia, sinus pauses or arrest, sinoatrial exit block, chronotropic incompetence, or alternating bradycardia and tachycardia (i.e., bradycardia-tachycardia syndrome). Clinical symptoms result from the hypoperfusion of end organs. About 50% of patients present with cerebral hypoperfusion (e.g., syncope, presyncope, lightheadedness, cerebrovascular accident). Other symptoms include palpitations, decreased physical activity tolerance, angina, muscular fatigue, or oliguria. A diagnosis is made by directly correlating symptoms with a bradyarrhythmia and eliminating potentially reversible extrinsic causes. Heart rate monitoring using electrocardiography or ambulatory cardiac event monitoring is performed based on the frequency of symptoms. An exercise stress test should be performed when symptoms are associated with exertion. The patient's inability to reach a heart rate of at least 80% of their predicted maximum (220 beats per minute - age) may indicate chronotropic incompetence, which is present in 50% of patients with sinus node dysfunction. First-line treatment for patients with confirmed sinus node dysfunction is permanent pacemaker placement with atrial-based pacing and limited ventricular pacing when necessary.


Assuntos
Estimulação Cardíaca Artificial/métodos , Eletrocardiografia , Frequência Cardíaca/fisiologia , Síndrome do Nó Sinusal/fisiopatologia , Nó Sinoatrial/fisiopatologia , Humanos , Síndrome do Nó Sinusal/diagnóstico , Síndrome do Nó Sinusal/terapia
2.
Medicine (Baltimore) ; 100(27): e26560, 2021 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-34232199

RESUMO

BACKGROUND: Right ventricular pacing (RVP) has been widely accepted as a traditional pacing strategy, but long-term RVP has detrimental impact on ventricular synchrony. However, left bundle branch pacing (LBBP) that evolved from His-bundle pacing could maintain ventricular synchrony and overcome its clinical deficiencies such as difficulty of lead implantation, His bundle damage, and high and unstable thresholds. This analysis aimed to appraise the clinical safety and efficacy of LBBP. METHODS: The Medline, PubMed, Embase, and the Cochrane Library databases from inception to November 2020 were searched for studies comparing LBBP and RVP. RESULTS: Seven trials with 451 patients (221 patients underwent LBBP and 230 patients underwent RVP) were included in the analysis. Pooled analyses verified that the paced QRS duration (QRSd) and left ventricular mechanical synchronization parameters of the LBBP capture were similar with the native-conduction mode (P > .7),but LBBP showed shorter QRS duration (weighted mean difference [WMD]: -33.32; 95% confidence interval [CI], -40.44 to -26.19, P < .001), better left ventricular mechanical synchrony (standard mean differences: -1.5; 95% CI: -1.85 to -1.14, P < .001) compared with RVP. No significant differences in Pacing threshold (WMD: 0.01; 95% CI: -0.08 to 0.09, P < .001), R wave amplitude (WMD: 0.04; 95% CI: -1.12 to 1.19, P = .95) were noted between LBBP and RVP. Ventricular impedance of LBBP was higher than that of RVP originally (WMD: 19.34; 95% CI: 3.13-35.56, P = .02), and there was no difference between the 2 groups after follow-up (WMD: 11.78; 95% CI: -24.48 to 48.04, P = .52). And follow-up pacing threshold of LBBP kept stability (WMD: 0.08; 95% CI: -0.09 to 0.25, P = .36). However, no statistical difference existed in ejection fraction between the 2 groups (WMD: 1.41; 95% CI: -1.72 to 4.54, P = .38). CONCLUSIONS: The safety and efficacy of LBBP was firstly verified by meta-analysis to date. LBBP markedly preserve ventricular electrical and mechanical synchrony compared with RVP. Meanwhile, LBBP had stable and excellent pacing parameters. However, LBBP could not be significant difference in ejection fraction between RVP during short- term follow-up.


Assuntos
Fascículo Atrioventricular/fisiopatologia , Bloqueio de Ramo/terapia , Estimulação Cardíaca Artificial/métodos , Frequência Cardíaca/fisiologia , Ventrículos do Coração/fisiopatologia , Função Ventricular Esquerda/fisiologia , Bloqueio de Ramo/fisiopatologia , Eletrocardiografia , Humanos , Resultado do Tratamento
3.
Medicine (Baltimore) ; 100(27): e26603, 2021 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-34232212

RESUMO

RATIONALE: The amount of aqueous humor that is constantly produced by the ciliary processes and the equal amount that flows out through the trabecular meshwork via the drainage angle or through the uveoscleral route is very small (2-3 µg/min each), representing approximately 1% of the content of the anterior chamber; therefore, it is challenging to visualize its flow. PATIENT CONCERNS: A 69-year-old man who had high intraocular pressure (IOP) (>20 mm Hg) with the maximum glaucoma eyedrop dose and presented with severe visual field loss (Humphrey Field Analyzer 30-2: -26.32 dB) had been implanted with a 350-mm2 Baerveldt tube of the aqueous chamber type for refractory open-angle glaucoma. The IOP ultimately decreased (<15 mm Hg) with no need for glaucoma eyedrops. DIAGNOSES: After the procedures, a fibrin membrane repeatedly formed on the anterior surface of the intraocular lens. INTERVENTIONS: This issue was resolved by two rounds of neodymium-doped yttrium aluminum granet (Nd:YAG) laser surgery and prescription steroidal eyedrops. OUTCOMES: During the laser surgery, an unusual and unintended fibrin flap appeared at the opening of the Baerveldt tube; this flap moved synchronously with the heartbeat, as verified by checking the pulse at the radial artery of the wrist. The fibrin flap mimicked the behavior of a cardiac valve, and the aqueous humor and stray fibrin particles mimicked the blood in the chambers of the heart. Although the Baerveldt tube itself is an artificial instrument that is not present in normal human eyes, we hypothesize that our observation shows the fundamental mechanism of aqueous humor drainage. LESSONS: This novel, vividly descriptive observation highlights the important role of the heartbeat as a drainage pump in aqueous humor flow dynamics and IOP homeostasis, which are treatment targets for glaucoma, the leading cause of blindness.


Assuntos
Fibrina , Implantes para Drenagem de Glaucoma , Glaucoma de Ângulo Aberto/cirurgia , Frequência Cardíaca/fisiologia , Pressão Intraocular/fisiologia , Retalhos Cirúrgicos , Trabeculectomia/métodos , Idoso , Humor Aquoso/metabolismo , Glaucoma de Ângulo Aberto/fisiopatologia , Humanos , Terapia a Laser/métodos , Lasers de Estado Sólido/uso terapêutico , Masculino , Acuidade Visual
5.
Int J Mol Sci ; 22(13)2021 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-34203369

RESUMO

Hypertrophic cardiomyopathy (HCM) is an inherited cardiac disorder affecting one in 500 of the general population. Atrial fibrillation (AF) is the most common arrhythmia in patients with HCM. We sought to characterize the atrial electrophysiological and structural substrate in young and aging Gly203Ser cardiac troponin-I transgenic (HCM) mice. At 30 weeks and 50 weeks of age (n = 6 per strain each group), the left atrium was excised and placed on a multi-electrode array (MEA) for electrophysiological study; subsequent histological analyses and plasma samples were analyzed for biomarkers of extracellular matrix remodeling and cell adhesion and inflammation. Wild-type mice of matched ages were included as controls. Young HCM mice demonstrated significantly shortened atrial action potential duration (APD), increased conduction heterogeneity index (CHI), increased myocyte size, and increased interstitial fibrosis without changes in effective refractory periods (ERP), conduction velocity (CV), inflammatory infiltrates, or circulating markers of extracellular matrix remodeling and inflammation. Aging HCM mice demonstrated aggravated changes in atria electrophysiology and structural remodeling as well as increased circulating matrix metalloproteinases (MMP)-2, MMP-3, and VCAM-1 levels. This model of HCM demonstrates an underlying atrial substrate that progresses with age and may in part be responsible for the greater propensity for AF in HCM.


Assuntos
Fibrilação Atrial/metabolismo , Cardiomiopatia Hipertrófica/metabolismo , Átrios do Coração/metabolismo , Troponina I/metabolismo , Potenciais de Ação/fisiologia , Animais , Fibrilação Atrial/genética , Remodelamento Atrial/genética , Remodelamento Atrial/fisiologia , Pressão Sanguínea/fisiologia , Eletrofisiologia Cardíaca , Cardiomiopatia Hipertrófica/genética , Modelos Animais de Doenças , Eletrofisiologia , Feminino , Átrios do Coração/patologia , Frequência Cardíaca/fisiologia , Humanos , Masculino , Mutação , Troponina I/genética
6.
J Int Soc Sports Nutr ; 18(1): 54, 2021 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-34238308

RESUMO

BACKGROUND: Recent studies in rodents indicate that a combination of exercise training and supplementation with nicotinamide adenine dinucleotide (NAD+) precursors has synergistic effects. However, there are currently no human clinical trials analyzing this. OBJECTIVE: This study investigates the effects of a combination of exercise training and supplementation with nicotinamide mononucleotide (NMN), the immediate precursor of NAD+, on cardiovascular fitness in healthy amateur runners. METHODS: A six-week randomized, double-blind, placebo-controlled, four-arm clinical trial including 48 young and middle-aged recreationally trained runners of the Guangzhou Pearl River running team was conducted. The participants were randomized into four groups: the low dosage group (300 mg/day NMN), the medium dosage group (600 mg/day NMN), the high dosage group (1200 mg/day NMN), and the control group (placebo). Each group consisted of ten male participants and two female participants. Each training session was 40-60 min, and the runners trained 5-6 times each week. Cardiopulmonary exercise testing was performed at baseline and after the intervention, at 6 weeks, to assess the aerobic capacity of the runners. RESULTS: Analysis of covariance of the change from baseline over the 6 week treatment showed that the oxygen uptake (VO2), percentages of maximum oxygen uptake (VO2max), power at first ventilatory threshold, and power at second ventilatory threshold increased to a higher degree in the medium and high dosage groups compared with the control group. However, there was no difference in VO2max, O2-pulse, VO2 related to work rate, and peak power after the 6 week treatment from baseline in any of these groups. CONCLUSION: NMN increases the aerobic capacity of humans during exercise training, and the improvement is likely the result of enhanced O2 utilization of the skeletal muscle. TRIAL REGISTRATION NUMBER: ChiCTR2000035138 .


Assuntos
Suplementos Nutricionais , Tolerância ao Exercício/fisiologia , Mononucleotídeo de Nicotinamida/administração & dosagem , Consumo de Oxigênio/fisiologia , Condicionamento Físico Humano/métodos , Corrida/fisiologia , Adulto , Ciclismo , Composição Corporal , Método Duplo-Cego , Teste de Esforço/métodos , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/metabolismo , NAD , Mononucleotídeo de Nicotinamida/metabolismo , Condicionamento Físico Humano/estatística & dados numéricos , Placebos/administração & dosagem , Fatores de Tempo
7.
Sci Rep ; 11(1): 14413, 2021 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-34257380

RESUMO

Lockdowns imposed to stem the spread of COVID-19 massively disrupted the daily routines of many worldwide, but studies to date have been mostly confined to observations within a limited number of countries, based on subjective reports and surveys from specific time periods during the pandemic. We investigated associations between lockdown stringency and objective sleep and resting-heart rate measures in ~ 113,000 users of a consumer sleep tracker across 20 countries from Jan to Jul 2020, compared to an equivalent period in 2019. With stricter lockdown measures, midsleep times were universally delayed, particularly on weekdays, while midsleep variability and resting heart rate declined. These shifts (midsleep: + 0.09 to + 0.58 h; midsleep variability: - 0.12 to - 0.26 h; resting heart rate: - 0.35 to - 2.08 bpm) correlated with the severity of lockdown across different countries (all Ps < 0.001) and highlight the graded influence of stringency lockdowns on human physiology.


Assuntos
COVID-19 , Controle de Doenças Transmissíveis/estatística & dados numéricos , Frequência Cardíaca/fisiologia , Sono/fisiologia , Humanos , Estudos Longitudinais , Análise Multinível , Quarentena
9.
Am J Cardiol ; 154: 106-110, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34233833

RESUMO

Heart rate reserve (HRR) during physical or pharmacological stress is a sign of cardiac autonomic function and sympathetic reserve, but it can be reduced during exercise for confounders such as poor motivation, drugs or physical fitness. In this study we sought to assess the prognostic meaning of HRR during dipyridamole stress echocardiography (DSE) in patients with abnormal chronotropic response to exercise. From 2004 to 2019, we prospectively acquired and retrospectively analyzed 379 patients (age 62 ± 11 years; ejection fraction 60 ± 5%) with suspected (n = 243) or known (n = 136) chronic coronary syndromes, referred to DSE for chronotropic incompetence during upright bicycle exercise-electrocardiography test defined as HRR used [(peak HR - rest HR) / (220 - age) - rest HR] ≤80% in patients off and ≤62% in patients on beta-blockers. All patients were in sinus rhythm and underwent DSE (0.84 mg/kg) within 3 months of exercise testing. During DSE, age-independent HRR (peak/rest HR) ≤1.22 was considered abnormal. All patients were followed-up. All-cause death was the only outcome measure. HRR during DSE was normal in 275 (73%) and abnormal in 104 patients (27%). During a follow-up of 9.0 ± 4.2 years, 67 patients (18%) died. The 15-year mortality rate was 23% in patients with normal and 61% in patients with abnormal HRR (p < 0.0001). At multivariable analysis a blunted HRR during DSE was an independent predictor of outcome (hazard ratio 2.01, 95% confidence intervals 1.23-3.29; p = 0.005) with age and diabetes, while neither inducible ischemia nor ongoing beta-blocker therapy were significant predictors. In conclusion, a blunted HRR during DSE predicts a worse survival in patients with chronotropic incompetence during exercise test. HRR during DSE is an appealingly simple biomarker of cardiac autonomic dysfunction independent of imaging, exercise and beta-blocker therapy.


Assuntos
Sistema Nervoso Autônomo/fisiopatologia , Ecocardiografia sob Estresse , Tolerância ao Exercício/fisiologia , Frequência Cardíaca/fisiologia , Mortalidade , Idoso , Dipiridamol , Teste de Esforço , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Vasodilatadores
10.
Scand J Med Sci Sports ; 31(9): 1796-1808, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34170582

RESUMO

BACKGROUND: Although structured exercise training is strongly recommended in cardiac patients, uncertainties exist about the methods for determining exercise intensity (EI) and their correspondence with effective EI obtained by ventilatory thresholds. We aimed to determine the first (VT1 ) and second ventilatory thresholds (VT2 ) in cardiac patients, sedentary subjects, and athletes comparing VT1 and VT2 with EI defined by recommendations. METHODS: We prospectively enrolled 350 subjects (mean age: 50.7±12.9 years; 167 cardiac patients, 150 healthy sedentary subjects, and 33 competitive endurance athletes). Each subject underwent ECG, echocardiography, and cardiopulmonary exercise testing. The percentages of peak VO2 , peak heart rate (HR), and HR reserve were obtained at VT1 and VT2 and compared with the EI definition proposed by the recommendations. RESULTS: VO2 at VT1 corresponded to high rather than moderate EI in 67.1% and 79.6% of cardiac patients, applying the definition of moderate exercise by the previous recommendations and the 2020 guidelines, respectively. Most cardiac patients had VO2  values at VT2 corresponding to very-high rather than high EI (59.9% and 50.3%, by previous recommendations and 2020 guidelines, respectively). A better correspondence between ventilatory thresholds and recommended EI domains was observed in healthy subjects and athletes (90% and 93.9%, respectively). CONCLUSIONS: EI definition based on percentages of peak HR and peak VO2  may misclassify the effective EI, and the discrepancy between the individually determined and the recommended EI is particularly relevant in cardiac patients. A ventilatory threshold-based rather than a range-based approach is advisable to define an appropriate level of EI.


Assuntos
Atletas , Exercício Físico/fisiologia , Cardiopatias/fisiopatologia , Ventilação Pulmonar/fisiologia , Comportamento Sedentário , Adulto , Ecocardiografia , Teste de Esforço/métodos , Feminino , Cardiopatias/classificação , Frequência Cardíaca/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Consumo de Oxigênio/fisiologia , Resistência Física , Estudos Prospectivos , Análise de Regressão , Função Ventricular Esquerda/fisiologia
11.
J Sci Med Sport ; 24(9): 908-912, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34059468

RESUMO

OBJECTIVES: To investigate whether participation in sport during the developmental stages of life is associated with cardiorespiratory fitness (CRF) in adulthood. DESIGN: Observational longitudinal study. METHODS: Participants were Generation 2 of the Raine Study. Questionnaires related to participation in sport were administered at ages 5, 8, 10, 14 and 17 years. These data were used to develop sex-specific trajectories of sports participation: (for males) Consistent Participators, Drop-Outs and Joiners; and (females) Consistent Participators, Non-Participators and Drop-Outs. At age 28.3 ±â€¯0.6 years, participants completed a graded maximal exercise test (i.e. V̇O2peak test). A General Linear Model assessed differences in CRF between trajectories. RESULTS: 402 participants n = 231 (57.5%) male, n = 171 (42.5%) female were included in the study. In males, Consistent Participators (all p < 0.001) and Joiners (p < 0.050) had greater fitness than Drop-Outs. In females, Consistent Participators had greater fitness than Non-Participators (p < 0.050), but there were no significant differences in fitness between Consistent Participators and Drop-Outs (p > 0.050) or Non-Participators and Drop-Outs (p > 0.050). CONCLUSION: Participation in sport during childhood and adolescence is associated with greater fitness in adulthood, compared to individuals who never participate or those that cease participation in adolescence. A simple dichotomous question regarding sports participation over the childhood and adolescent period can be implemented to predict better fitness outcomes in young adulthood. Childhood and adolescence could be an opportune stage in life for parents, schools and governments to facilitate participation in sport and prevent drop out, as it may have an impact on long term risk reduction, with associated health and economic benefits.


Assuntos
Fatores Etários , Aptidão Cardiorrespiratória/fisiologia , Esportes Juvenis/fisiologia , Adolescente , Adulto , Criança , Pré-Escolar , Teste de Esforço , Feminino , Frequência Cardíaca/fisiologia , Humanos , Modelos Lineares , Estudos Longitudinais , Masculino , Consumo de Oxigênio/fisiologia , Inquéritos e Questionários
12.
Eur J Endocrinol ; 185(2): 343-353, 2021 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-34085953

RESUMO

Objective: Hypoglycemia is associated with an increased risk of cardiovascular disease including cardiac arrhythmias. We investigated the effect of hypoglycemia in the setting of acute glycemic fluctuations on cardiac rhythm and cardiac repolarization in insulin-treated patients with type 2 diabetes compared with matched controls without diabetes. Design: A non-randomized, mechanistic intervention study. Methods: Insulin-treated patients with type 2 diabetes (n = 21, age (mean ± s.d.): 62.8 ± 6.5 years, BMI: 29.0 ± 4.2 kg/m2, HbA1c: 6.8 ± 0.5% (51.0 ± 5.4 mmol/mol)) and matched controls (n = 21, age: 62.2 ± 8.3 years, BMI 29.2 ± 3.5 kg/m2, HbA1c: 5.3 ± 0.3% (34.3 ± 3.3 mmol/mol)) underwent a sequential hyperglycemic and hypoglycemic clamp with three steady-states of plasma glucose: (i) fasting plasma glucose, (ii) hyperglycemia (fasting plasma glucose +10 mmol/L) and (iii) hyperinsulinemic hypoglycemia (plasma glucose < 3.0 mmol/L). Participants underwent continuous ECG monitoring and blood samples for counterregulatory hormones and plasma potassium were obtained. Results: Both groups experienced progressively increasing heart rate corrected QT (Fridericia's formula) interval prolongations during hypoglycemia ((∆mean (95% CI): 31 ms (16, 45) and 39 ms (24, 53) in the group of patients with type 2 diabetes and controls, respectively) with similar increases from baseline at the end of the hypoglycemic phase (P = 0.43). The incidence of ventricular premature beats increased significantly in both groups during hypoglycemia (P = 0.033 and P < 0.0001, respectively). One patient with type 2 diabetes developed atrial fibrillation during recovery from hypoglycemia. Conclusions: In insulin-treated patients with type 2 diabetes and controls without diabetes, hypoglycemia causes clinically significant and similar increases in cardiac repolarization that might increase vulnerability for serious cardiac arrhythmias and sudden cardiac death.


Assuntos
Arritmias Cardíacas/fisiopatologia , Diabetes Mellitus Tipo 2/fisiopatologia , Hipoglicemia/fisiopatologia , Idoso , Arritmias Cardíacas/sangue , Pressão Sanguínea/fisiologia , Diabetes Mellitus Tipo 2/sangue , Eletrocardiografia , Feminino , Glucagon/sangue , Hormônio do Crescimento/sangue , Frequência Cardíaca/fisiologia , Humanos , Hidrocortisona/sangue , Hipoglicemia/sangue , Masculino , Pessoa de Meia-Idade , Norepinefrina/sangue , Potássio/sangue
13.
J Int Soc Sports Nutr ; 18(1): 51, 2021 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-34183020

RESUMO

BACKGROUND: Dietary supplement use among recreational athletes is common, with the intention of reducing inflammation and improving recovery. We aimed to describe the relationship between omega-3 fatty acid supplement use and inflammation induced by strenuous exercise. METHODS: C-reactive protein (CRP) concentrations were measured in 1002 healthy recreational athletes before and 24 h after a 91-km bicycle race. The use of omega-3 fatty acid supplements was reported in 856 out of 1002 recreational athletes, and the association between supplement use and the exercise-induced CRP response was assessed. RESULTS: Two hundred seventy-four subjects reported regular use of omega-3 fatty acid supplements. One hundred seventy-three of these used cod liver oil (CLO). Regular users of omega-3 fatty acid supplements had significantly lower basal and exercise-induced CRP levels as compared to non-users (n = 348, p < 0.001). Compared to non-users, regular users had a 27% (95% confidence interval (CI): 14-40) reduction in Ln CRP response (unadjusted model, p < 0.001) and 16% (95% CI: 5-28, p = 0.006) reduction after adjusting for age, sex, race duration, body mass index, delta creatine kinase, MET hours per week, resting heart rate and higher education. CLO was the primary driver of this response with a 34% (95% CI: 19-49) reduction (unadjusted model, p < 0.001) compared to non-users. Corresponding numbers in the adjusted model were 24% (95% CI: 11-38, p < 0.001). CONCLUSION: Basal CRP levels were reduced, and the exercise-induced CRP response was attenuated in healthy recreational cyclists who used omega-3 fatty acid supplements regularly. This effect was only present in regular users of CLO. TRIAL REGISTRATION: NCT02166216 , registered June 18, 2014 - Retrospectively registered.


Assuntos
Proteína C-Reativa/análise , Óleo de Fígado de Bacalhau/administração & dosagem , Exercício Físico/fisiologia , Vitaminas/administração & dosagem , Adulto , Ciclismo/fisiologia , Intervalos de Confiança , Creatina Quinase/sangue , Ácidos Graxos Ômega-3/administração & dosagem , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
14.
Health Psychol ; 40(5): 316-325, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34152785

RESUMO

OBJECTIVE: Lesbian, gay, and bisexual (LGB) individuals who report greater minority stress (e.g., discrimination) are at an elevated risk for multiple health problems. However, few studies have examined physiological mechanisms that might link minority stress to health. This study tested how cardiovascular and cortisol responses to a laboratory-induced social stressor differed when that stressor contained an additional minority stress component. METHOD: LGB adults (n = 141; 51% male, 49% female) participated in a social stress task in which they were interviewed by a prerecorded confederate. Participants were randomized to receive information that their interviewer held either antigay or progay social/political beliefs. Cardiovascular reactivity and salivary cortisol were assessed at baseline, during the task, and during recovery. RESULTS: All participants experienced significant task-related increases in heart rate (HR), systolic blood pressure (SBP), and diastolic blood pressure (DBP). However, participants in the antigay condition had greater increases in HR and SBP during the task and smaller decreases in SBP during recovery. Salivary cortisol increased significantly only in the antigay condition. High frequency heart rate variability (hfHRV) was constant throughout the stress task for participants in the progay condition but decreased significantly during the task for participants in the antigay condition. CONCLUSIONS: Minority stress has the potential to affect LGB individuals' health through cardiovascular and endocrine mechanisms. Moreover, its physiological signature may differ from other social stress in ways that have implications for health and emotion regulation more broadly. (PsycInfo Database Record (c) 2021 APA, all rights reserved).


Assuntos
Pressão Sanguínea/fisiologia , Frequência Cardíaca/fisiologia , Hidrocortisona/metabolismo , Minorias Sexuais e de Gênero/psicologia , Estresse Psicológico/fisiopatologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Saliva/química , Minorias Sexuais e de Gênero/estatística & dados numéricos , Adulto Jovem
15.
Medicine (Baltimore) ; 100(25): e26396, 2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-34160422

RESUMO

BACKGROUND: Cardiovascular diseases have become a prominent threat to public health and quality of life. In recent years, some studies have reported that ivabradine can improve the cardiac function and prognosis of patients with acute myocardial infarction (AMI). Therefore, we perform a protocol for systematic review and meta-analysis to evaluate the efficacy of ivabradine for treating AMI. METHODS: This protocol of systematic review and meta-analysis has been drafted under the guidance of the preferred reporting items for systematic reviews and meta-analyses protocols. We will search PubMed, Cochrane Library, Embase, Web of Science, and Medline databases for relevant studies. In addition, we will also collect 4 databases of China: China National Knowledge Infrastructure, China Biomedical Literature Database, China Science Journal Database, and Wan-fang Database. Risk of bias will be assessed using the Cochrane Handbook risk of bias assessment tool version (V.5.1.0). We will use STATA 16.0 software (Stata Corporation, College Station, TX) to perform data analysis. RESULTS: The results of this systematic review and meta-analysis will be published in a peer-reviewed journal. CONCLUSION: We hypothesized that ivabradine can reduce the resting heart rate and improve heart function in patients with AMI.


Assuntos
Ivabradina/administração & dosagem , Infarto do Miocárdio/tratamento farmacológico , Frequência Cardíaca/efeitos dos fármacos , Frequência Cardíaca/fisiologia , Humanos , Metanálise como Assunto , Infarto do Miocárdio/fisiopatologia , Descanso/fisiologia , Volume Sistólico/efeitos dos fármacos , Revisões Sistemáticas como Assunto , Resultado do Tratamento , Função Ventricular Esquerda/efeitos dos fármacos
16.
BMC Neurol ; 21(1): 222, 2021 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-34116663

RESUMO

BACKGROUND: Increased heart rate (HR) has been associated with stroke risk and outcomes. MATERIAL AND METHODS: We analyzed 1,420 patients from a hospital-based stroke registry with acute ischemic stroke (AIS). Mean initial in-hospital HR and the coefficient of variation of HR (HR-CV) were derived from the values recorded during the first 3 days of hospitalization. The study outcome was the 3-month functional outcome. Odds ratios (ORs) with 95% confidence intervals (CIs) were estimated using multivariable logistic regression analysis. RESULTS: A higher mean HR level was significantly and continuously associated with a higher probability of unfavorable functional outcomes. Compared with the reference group (mean HR < 70 beats per minute), the multivariate-adjusted OR for an unfavorable outcome was 1.81 (95% CI, 1.25-2.61) for a mean HR ≥ 70 and < 80 beats per minute, 2.52 (95% CI, 1.66 - 3.52) for a mean HR ≥ 80 and < 90 beats per minute, and 3.88 (95% CI, 2.20-6.85) for mean HR ≥ 90 beats per minute. For stroke patients with a history of hypertension, the multivariate-adjusted OR for patients with a HR-CV ≥ 0.12 (versus patients with a HR-CV < 0.08 as a reference) was 1.73 (95% CI, 1.11-2.70) for an unfavorable outcome. CONCLUSIONS: Our results indicated that a high initial in-hospital HR was significantly associated with unfavorable 3-month functional outcomes in patients with AIS. In addition, stroke patients with a HR-CV ≥ 0.12 also had unfavorable outcomes compared with those with a HR-CV < 0.08 if they had a history of hypertension.


Assuntos
Frequência Cardíaca/fisiologia , Hospitalização/estatística & dados numéricos , AVC Isquêmico/epidemiologia , Humanos , Resultado do Tratamento
17.
Int J Mol Sci ; 22(9)2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-34068698

RESUMO

Immune, neuroendocrine, and autonomic nervous system dysregulation in anorexia nervosa lead to cardiovascular complications that can potentially result in increased morbidity and mortality. It is suggested that a complex non-invasive assessment of cardiovascular autonomic regulation-cardiac vagal control, sympathetic vascular activity, and cardiovascular reflex control-could represent a promising tool for early diagnosis, personalized therapy, and monitoring of therapeutic interventions in anorexia nervosa particularly at a vulnerable adolescent age. In this view, we recommend to consider in the diagnostic route, at least in the subset of patients with peripheral microvascular symptoms, a nailfold video-capillaroscopy as an easy not invasive tool for the early assessing of possible cardiovascular involvement.


Assuntos
Anorexia Nervosa/patologia , Anormalidades Cardiovasculares/patologia , Doenças Vasculares Periféricas/patologia , Anorexia Nervosa/complicações , Anorexia Nervosa/imunologia , Anorexia Nervosa/metabolismo , Anormalidades Cardiovasculares/complicações , Anormalidades Cardiovasculares/imunologia , Anormalidades Cardiovasculares/metabolismo , Frequência Cardíaca/fisiologia , Humanos , Sistema Imunitário/patologia , Sistemas Neurossecretores/metabolismo , Sistemas Neurossecretores/patologia , Doenças Vasculares Periféricas/complicações , Doenças Vasculares Periféricas/imunologia , Doenças Vasculares Periféricas/metabolismo , Nervo Vago/metabolismo , Nervo Vago/patologia
18.
Nat Med ; 27(6): 1105-1112, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34031607

RESUMO

Vital signs, including heart rate and body temperature, are useful in detecting or monitoring medical conditions, but are typically measured in the clinic and require follow-up laboratory testing for more definitive diagnoses. Here we examined whether vital signs as measured by consumer wearable devices (that is, continuously monitored heart rate, body temperature, electrodermal activity and movement) can predict clinical laboratory test results using machine learning models, including random forest and Lasso models. Our results demonstrate that vital sign data collected from wearables give a more consistent and precise depiction of resting heart rate than do measurements taken in the clinic. Vital sign data collected from wearables can also predict several clinical laboratory measurements with lower prediction error than predictions made using clinically obtained vital sign measurements. The length of time over which vital signs are monitored and the proximity of the monitoring period to the date of prediction play a critical role in the performance of the machine learning models. These results demonstrate the value of commercial wearable devices for continuous and longitudinal assessment of physiological measurements that today can be measured only with clinical laboratory tests.


Assuntos
Técnicas Biossensoriais , Monitorização Fisiológica/métodos , Sinais Vitais/fisiologia , Dispositivos Eletrônicos Vestíveis , Temperatura Corporal/fisiologia , Resposta Galvânica da Pele , Frequência Cardíaca/fisiologia , Humanos , Movimento
19.
J Sci Med Sport ; 24(9): 876-880, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33992537

RESUMO

OBJECTIVES: The Buffalo Concussion Treadmill Test (BCTT) is a safe and validated tool to assess exercise tolerance after sport-related concussion (SRC). Sex differences may affect the interpretation of this systematic exertion test in the concussed population, which is important for clinicians. The purpose of this study was to examine sex differences in BCTT performance in adolescents with acute SRC. DESIGN: Prospective cohort. METHODS: Male (n = 103, 15.3 ±â€¯2 years) and female (n = 87, 15.1 ±â€¯2 years) adolescents with SRC performed the BCTT within 10 days of injury. Heart rate (HR), HR threshold (HRt), Delta HR (difference between resting HR and HRt), symptom severity on Visual Analog Scale (VAS) and symptoms exacerbated on the BCTT were collected and compared. RESULTS: Males had lower resting HR (M: 70.9 ±â€¯12 vs F: 75.7 ±â€¯13 bpm, p < 0.01) and reached a lower HRt than females (M: 134.7 ±â€¯23 vs F: 141.5 ±â€¯25 bpm, p = 0.05). Sexes did not differ on Delta HR (M: 63.8 ±â€¯26 vs F: 65.9 ±â€¯24 bpm, p = 0.57), total treadmill time (M: 9.3 ±â€¯5 vs F: 8.4 ±â€¯4 min, p = 0.20), maximum VAS (M: 5.0 ±â€¯2 vs F: 5.4 ±â€¯2, p = 0.18) or incidence of a change in VAS (M: 91% vs F: 94%, p = 0.43) on the BCTT. CONCLUSIONS: Although males may reach symptom exacerbation at a slightly lower mean HRt than females on the BCTT within 10 days of SRC, the BCTT provides comparable information and both sexes reach symptom exacerbation at similar Delta HR.


Assuntos
Traumatismos em Atletas/fisiopatologia , Concussão Encefálica/fisiopatologia , Progressão da Doença , Tolerância ao Exercício/fisiologia , Frequência Cardíaca/fisiologia , Fatores Sexuais , Adolescente , Teste de Esforço/métodos , Feminino , Humanos , Masculino , New York , Estudos Prospectivos , Descanso/fisiologia , Fatores de Tempo , Escala Visual Analógica
20.
Eur J Pharmacol ; 904: 174182, 2021 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-34004212

RESUMO

Restraint stress (RS) is an unavoidable stress model that triggers activation of the autonomic nervous system, endocrine activity, and behavioral changes in rodents. Furthermore, RS induces secretion of oxytocin into the bloodstream, indicating a possible physiological role in the stress response in this model. The presence of oxytocin receptors in vessels and heart favors this possible idea. However, the role of oxytocin secreted in RS and effects on the cardiovascular system are still unclear. The aim of this study was to analyze the influence of oxytocin on cardiovascular effects during RS sessions. Rats were subjected to pharmacological (blockade of either oxytocin, vasopressin, or muscarinic receptors) or surgical (hypophysectomy or sinoaortic denervation) approaches to study the functional role of oxytocin and its receptor during RS. Plasma levels of oxytocin and vasopressin were measured after RS. RS increased arterial pressure, heart rate, and plasma oxytocin content, but not vasopressin. Treatment with atosiban (a Gi biased agonist) inhibited restraint-evoked tachycardia without affecting blood pressure. However, this effect was no longer observed after sinoaortic denervation, homatropine (M2 muscarinic antagonist) treatment or hypophysectomy, indicating that parasympathetic activation mediated by oxytocin secreted to the periphery is responsible for blocking the increase in tachycardic responses observed in the atosiban-treated group. Corroborating this, L-368,899 (oxytocin antagonist) treatment showed an opposite effect to atosiban, increasing tachycardic responses to restraint. Thus, this provides evidence that oxytocin secreted to the periphery attenuates tachycardic responses evoked by restraint via increased parasympathetic activity, promoting cardioprotection by reducing the stress-evoked heart rate increase.


Assuntos
Ocitocina/metabolismo , Restrição Física/fisiologia , Estresse Psicológico/fisiopatologia , Animais , Antagonistas dos Receptores de Hormônios Antidiuréticos/farmacologia , Barorreflexo/efeitos dos fármacos , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/fisiologia , Frequência Cardíaca/efeitos dos fármacos , Frequência Cardíaca/fisiologia , Masculino , Agonistas Muscarínicos/farmacologia , Ocitocina/sangue , Parassimpatolíticos/farmacologia , Ratos Wistar , Receptor Muscarínico M2/antagonistas & inibidores , Receptores de Vasopressinas/fisiologia , Estresse Psicológico/sangue , Taquicardia/fisiopatologia , Tropanos/farmacologia , Vasopressinas/sangue , Vasotocina/análogos & derivados , Vasotocina/farmacologia
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