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Resolvins and maresins, members of the specialized proresolving mediator (SPM) family, are omega-3 fatty acid-derived lipid mediators that attenuate inflammation. We hypothesized that they play a role in the pathophysiology of coronary microvascular dysfunction (CMD) in women with ischemia and no obstructive coronary disease. In a pilot study, we measured the D-series resolvins (D1, D2, D3, and D5), resolvin E1, maresin 1, docosahexaenoic acid, eicosapentaenoic acid (precursor of resolvin E1), and 18-hydroxyeicosapentaenoic acid by mass spectrometry in the peripheral blood of 31 women enrolled in the Women's Ischemia Trial to Reduce Events in Nonobstructive CAD (WARRIOR) trial who had confirmed CMD assessed by coronary flow reserve. We compared SPM levels with 12 gender and age-matched reference subjects. Compared with the reference subject group, those with CMD had significantly lower plasma concentrations of resolvin D1 and maresin 1 and significantly higher levels of docosahexaenoic acid and 18-hydroxyeicosapentaenoic acid. In conclusion, insufficient or ineffective SPM production may play a role in the pathophysiology of CMD. If our results are validated in a larger cohort, omega-3 fatty acid supplementation could be tested as a novel treatment for these patients.
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Ácidos Docosa-Hexaenoicos/sangue , Ácido Eicosapentaenoico/sangue , Ácidos Hidroxieicosatetraenoicos/sangue , Microcirculação/fisiologia , Isquemia Miocárdica/sangue , Idoso , Ácido Eicosapentaenoico/análogos & derivados , Ácidos Graxos Insaturados/sangue , Feminino , Humanos , Espectrometria de Massas , Pessoa de Meia-Idade , Isquemia Miocárdica/etiologia , Isquemia Miocárdica/prevenção & controle , Projetos PilotoRESUMO
Dietary or supplemental calcium intake has long been encouraged for optimal bone health. However, more recently, the safety of calcium supplementation has been questioned because of a possible association between supplemental calcium and cardiovascular risk. Whereas calcium may have a beneficial or neutral effect on cardiovascular risk factors such as blood pressure, cholesterol, weight, and diabetes, available evidence does not provide a definitive answer for an association with cardiovascular disease (CVD). To date, no calcium trials have studied cardiovascular disease as a primary end point, and larger trials with longer follow-up are needed. In this review, we present results from observational studies and randomized controlled trials (RCTs) that have evaluated calcium intake (dietary or supplemental) in relation to cardiovascular risk factors and cardiovascular disease as a secondary outcome. Results from RCTs are mixed regarding CVD risk in those using supplemental calcium with or without vitamin D, and more large-scale randomized trials designed specifically with CVD as the primary end point are needed. Evidence suggests that it is reasonable to encourage adequate dietary calcium intake, especially for postmenopausal women who are at greatest risk for osteoporotic fracture.
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BACKGROUND: Heart rate variability (HRV) is reduced in stable ischemic heart disease (SIHD) patients and is associated with sudden cardiac death (SCD). We evaluated the impact of traditional acupuncture (TA) on cardiac autonomic function measured by HRV in SIHD patients. METHODS: We conducted a randomized controlled study of TA, sham acupuncture (SA), and waiting control (WC) in 151 SIHD subjects. The TA group received needle insertion at acupuncture sites, the SA group received a sham at non-acupuncture sites, while the WC group received nothing. The TA and SA groups received 3 treatments/week for 12 weeks. 24-Hour, mental arithmetic stress, and cold pressor (COP) HRV was collected at entry and exit, along with BP, lipids, insulin resistance, hs-CRP, salivary cortisol, peripheral endothelial function by tonometry (PAT), and psychosocial variables. RESULTS: Mean age was 63 ± 10; 50% had prior myocardial infarction. Comparison of WC and SA groups demonstrated differences consistent with the unblinded WC status; therefore by design, the control groups were not merged. Exit mental stress HRV was higher in TA vs. SA for markers of parasympathetic tone (p ≤ 0.025), including a 17% higher vagal activity (p=0.008). There were no differences in exit 24-hour or COP HRV, BP, lipids, insulin resistance, hs-CRP, salivary cortisol, PAT, or psychosocial variables. CONCLUSIONS: TA results in intermediate effects on autonomic function in SIHD patients. TA effect on HRV may be clinically relevant and should be explored further. These data document feasibility and provide sample size estimation for a clinical trial of TA in SIHD patients for the prevention of SCD. CONDENSED ABSTRACT: We conducted a randomized, single-blind trial of traditional acupuncture (TA) vs. sham acupuncture (SA) vs waiting control (WC) in stable ischemic heart disease (SIHD) patients to evaluate cardiac autonomic function measured by heart rate variability (HRV). Exit mental stress HRV was higher in the TA compared to SA group for time and frequency domain markers of parasympathetic tone (all p ≤ 0.025), including a 17% higher vagal activity (p=0.008). These data document feasibility and provide sample size estimation for an outcome-based clinical trial of TA in SIHD patients for the prevention of sudden cardiac death.
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Terapia por Acupuntura/métodos , Isquemia Miocárdica/diagnóstico , Isquemia Miocárdica/terapia , Terapia por Acupuntura/normas , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Placebos/normas , Método Simples-Cego , Fatores de TempoRESUMO
CONTEXT: Coronary heart disease (CHD) remains the number one killer of men and women in the United States, and despite traditional secondary prevention, individuals with the disease remain at risk. Endothelial progenitor cells (EPCs) may have beneficial effects on atherosclerosis, angiogenesis, and vascular repair and may contribute systemically to ongoing endogenous repair processes. Traditional acupuncture (TA), a modality used in the practice of Chinese medicine, appears to have beneficial effects in many areas associated with CHD. OBJECTIVE: The study examined the effects of TA on circulating EPCs in individuals with CHD. DESIGN: The research team performed a randomized, controlled pilot study. SETTING: All interventions were performed at the Cedars-Sinai Medical Center in Los Angeles, CA. PARTICIPANTS: The study included 13 participants in 3 groups: (1) TA (n = 5), (2) sham acupuncture (SA, n = 5), or (3) waiting control (WC, n = 3). INTERVENTION: The TA group received acupuncture treatments for 12 wk at CHD-specific sites, while the SA group received no-needle pressure at nonacupuncture sites for the same period, and the WC group received no intervention. OUTCOME MEASURES: The study measured the number of EPCs circulating in peripheral blood to determine cell surface markers for expressions of cluster of differentiation 34, 133 (CD34+/CD133+) and vascular endothelial growth factor receptor 2 (VEGF-R2+). RESULTS: Eight men and 5 women with a mean age of 59 ± 10.9 y were included. Compared with their measurements at baseline, members of the TA group had a significantly greater change in the level of EPCs expressing CD34+/VEGF-R2+ compared with the SA group (P = .04). No group differences were evident in immature EPCs expressing CD34+/CD133+. CONCLUSION: The study's results suggest that TA can alter the number of EPCs circulating in peripheral blood by increasing the mobilization of the VEGF-R2+ EPC subpopulations. Further studies are warranted to evaluate whether TA can beneficially affect CHD via augmentation of EPC regenerative pathways.
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OBJECTIVE: To determine the relationship of vitamin c intake from supplements vs food on early atherosclerosis detected by carotid intima media thickness (IMT). BACKGROUND: Oxidative stress and endothelial dysfunction play a critical role in the pathogenesis of atherosclerosis. Dietary vitamin C appears to have anti-oxidant properties and beneficial relations to endothelial function, yet vitamin C taken as a vitamin supplement does not appear to protect from cardiovascular events. The impact of vitamin c intake from supplements vs food on progression of atherosclerosis is unknown. METHODS: We examined 3-year progression of carotid IMT in a randomly sampled cohort of 573 healthy women and men aged 40-60 years. Progression of carotid IMT was determined bilaterally with B-mode ultrasound at 3 examinations (1.5-year intervals). Intake of dietary vitamin C was measured by six, 24-hour recall interviews. Intake of vitamin C from vitamin supplements was measured by questionnaire in quartiles of supplement intake and no supplement. Vitamin C wasmeasured in plasma as ascorbic acid. RESULTS: Carotid IMT progressed 10.0±16.5 µm/year (mean±SD) among all those with follow-up (n=500; 87%). For those who took vitamin C supplements, carotid IMT progression increased with dose (p-trend=0.0009). Among persons in the highest quartile (857-5000 mg/day) of vitamin C supplement intake compared to those not consuming any vitamin C supplements, carotid IMT progression increased three-fold (20.3±2.6 versus 7.6±1.8 µm/year (mean±SD); p<0.001). The adverse association of vitamin C supplement intake with carotid IMT was two-fold greater in the upper tertile of serum cholesterol compared to the lower two tertiles (p=0.01). In contrast to the adverse association of vitamin C supplements, vitamin C intake from food had a weak protective relationship on carotid IMT progression (reduced progression -5.0±1.9 µm/year; p=0.008). CONCLUSIONS: Vitamin C supplementation is associated with accelerated early atherosclerosis measured by carotid IMT compared to a protective association with vitamin C from food. Theadverse association of vitamin C supplementation may be greater in patients with higher serum cholesterol levels. The current results provide a potential mechanistic understanding for the observed differences between Vitamin C in supplements vs food in prior studies. Given these observations,vitamin C supplementation does not appear to be currently advisable for prevention or treatment of atherosclerosis.
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OBJECTIVE: The aim of this study was to conduct a pilot study for the feasibility of planning a definitive clinical trial comparing traditional acupuncture (TA) with sham acupuncture (SA) and waiting control (WC) on menopause-related vasomotor symptoms (VMS), quality of life, and the hypothalamic-pituitary-adrenal axis in perimenopausal and postmenopausal women. METHODS: Thirty-three perimenopausal and postmenopausal women with at least seven VMS daily were randomized to TA, SA, or WC. The TA and SA groups were given three treatments per week for 12 weeks. Outcomes included the number and severity of VMS, Menopause-Specific Quality of Life Questionnaire, Beck Depression Inventory, Spielberg State-Trait Anxiety Instrument, Pittsburgh Quality Sleep Index, 24-hour urine cortisol and metabolites, and adrenocorticotropic hormone stimulation testing. RESULTS: Both the TA and SA groups demonstrated improved VMS trends compared with the WC group (Δ -3.5 ± 3.00 vs -4.1 ± 3.79 vs -1.2 ± 2.4, respectively; P = 20) and significantly improved Menopause-Specific Quality of Life Questionnaire vasomotor scores (Δ -1.5 ± 2.02 vs -1.8 ± 1.52 vs -0.3 ± 0.64, respectively; P = 0.04). There were no psychosocial group differences. Exit 24-hour urinary measures were lower in the TA versus the SA or WC group in total cortisol metabolites (4,658.9 ± 1,670.9 vs 7,735.8 ± 3,747.9 vs 5,166.0 ± 2,234.5, P = 0.03; respectively) and dehydroepiandrosterone (41.4 ± 27.46, 161.2 ± 222.77, and 252.4 ± 385.40, respectively; P = 0.05). The response data on adrenocorticotropic hormone stimulation cortisol also trended in the hypothesized direction (P = 0.17). CONCLUSIONS: Both TA and SA reduce VMS frequency and severity and improve VMS-related quality of life compared with WC; however, TA alone may impact the hypothalamic-pituitary-adrenal axis. This association is viewed as preliminary and hypothesis generating and should be explored in a large clinical trial.
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Terapia por Acupuntura , Fogachos/prevenção & controle , Menopausa/fisiologia , Feminino , Humanos , Sistema Hipotálamo-Hipofisário/fisiologia , Pessoa de Meia-Idade , Perimenopausa/fisiologia , Projetos Piloto , Sistema Hipófise-Suprarrenal/fisiologia , Placebos , Pós-Menopausa/fisiologia , Qualidade de Vida , Método Simples-Cego , Inquéritos e QuestionáriosRESUMO
Patients with persistent chest pain and no obstructive coronary artery disease are often labeled as having noncardiac pain and not offered further cardiologic testing or treatment. Diagnostic uncertainty for persistent chest pain is associated with adverse quality of life, morbidity, and health care costs. Two underdiagnosed cardiac causes for persistent chest pain include microvascular coronary disease and abnormal cardiac nociception. Microvascular coronary disease is associated with an increased risk of adverse cardiovascular events such as myocardial infarction, congestive heart failure, and sudden cardiac death, and treatment directed at improving endothelial function can improve outcomes. Abnormal cardiac nociception is also a cause for persistent chest pain caused by heightened coronary pain perception. Coronary reactivity testing allows for direct measurement of blood flow characteristics in response to vasoactive agents for the diagnoses of microvascular coronary disease and can be a useful tool to differentiate causes of chest pain. Coronary reactivity testing is an invasive method for assessing coronary vascular function, with current evidence suggesting that its associated risk is relatively low compared with the adverse prognosis associated with microvascular coronary dysfunction. Accurate diagnosis in patients with persistent chest pain and normal coronary arteries can be challenging and deserves adequate investigation in light of the associated morbidity, mortality, and health care costs.
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Dor no Peito/etiologia , Técnicas de Diagnóstico Cardiovascular , Angina Microvascular/diagnóstico , Nociceptores , Radiografia Intervencionista , Adulto , Velocidade do Fluxo Sanguíneo , Fármacos Cardiovasculares/uso terapêutico , Dor no Peito/terapia , Circulação Coronária , Vasoespasmo Coronário/diagnóstico , Diagnóstico Diferencial , Feminino , Humanos , Imipramina/uso terapêutico , Angina Microvascular/tratamento farmacológico , Pessoa de Meia-Idade , Medição da Dor , Estimulação Elétrica Nervosa Transcutânea , VasodilatadoresRESUMO
BACKGROUND: Significant cardiac neural and electrophysiologic remodeling occurs with hypercholesterolemia (HC). Whether simvastatin can reverse HC-induced remodeling is unclear. OBJECTIVE: The purpose of this study was to determine the mechanisms underlying the antiarrhythmic effects of statins. METHODS: Rabbits (N = 38) were fed HC chow (HC), standard chow (Control), HC chow followed by standard chow (Withdrawal), or HC chow and simvastatin (Statin) for 8 weeks. The hearts then were Langendorff-perfused for electrophysiologic studies. Nerves were identified by immunostaining of growth-associated protein-43 (GAP43) and tyrosine hydroxylase (TH). Action potential duration (APD) restitution in normal hearts with (N = 5) and without (N = 5) simvastatin therapy also was studied. RESULTS: Serum cholesterol levels (mg/dL) were 1,855 +/- 533 in HC, 50 +/- 21 in Control, 570 +/- 115 in Withdrawal, and 873 +/- 112 in Statin groups (P <.001). Compared with HC (16,700 +/- 5,342; 12,200 +/- 3,878 microm(2)/mm(2)), the Statin group had significantly reduced GAP43-positive (10,289 +/- 3,393 microm(2)/mm(2), P = .03) and TH-positive (7,685 +/- 2,959 microm(2)/mm(2), P = .04) nerve density, respectively. APD was longer in HC rabbits than in controls (192 +/- 20 ms vs 174 +/- 17 ms; P <.03). Withdrawal and Statin groups had less APD prolongation than HC group. Statin group has less repolarization heterogeneity than HC group (P <.01). Statin therapy flattened the slope of APD restitution in normal hearts. Ventricular fibrillation was either induced or occurred spontaneously in 79% of hearts in HC, 20% in Control, and 66% in Withdrawal groups. However, there was no VF in hearts of Statin group (P <.001). CONCLUSION: Simvastatin significantly reduced vulnerability to ventricular fibrillation via the mechanism of reduction of HC-induced neural and electrophysiologic remodeling.
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Colesterol/sangue , Sistema de Condução Cardíaco/patologia , Ventrículos do Coração/inervação , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Hipercolesterolemia/tratamento farmacológico , Sinvastatina/uso terapêutico , Remodelação Ventricular/efeitos dos fármacos , Animais , Técnicas Eletrofisiológicas Cardíacas , Feminino , Seguimentos , Sistema de Condução Cardíaco/efeitos dos fármacos , Sistema de Condução Cardíaco/fisiopatologia , Ventrículos do Coração/efeitos dos fármacos , Ventrículos do Coração/fisiopatologia , Hipercolesterolemia/sangue , Hipercolesterolemia/fisiopatologia , Imuno-Histoquímica , Coelhos , Resultado do Tratamento , Fibrilação Ventricular/fisiopatologia , Fibrilação Ventricular/prevenção & controle , Remodelação Ventricular/fisiologiaRESUMO
BACKGROUND: The metabolic syndrome is thought to be a contributor to coronary heart disease (CHD), and components of the syndrome have been identified as possible therapeutic targets. Previous data implicate neurohumoral activation related to psychosocial stress as a contributor to the metabolic syndrome. The aim of this study was to evaluate the efficacy of transcendental meditation (TM) on components of the metabolic syndrome and CHD. METHODS: We conducted a randomized, placebo-controlled clinical trial of 16 weeks of TM or active control treatment (health education), matched for frequency and time, at an academic medical center in a total of 103 subjects with stable CHD. Main outcome measures included blood pressure, lipoprotein profile, and insulin resistance determined by homeostasis model assessment (calculated as follows: [(fasting plasma glucose level [in milligrams per deciliter] x fasting plasma insulin level [in microunits per milliliter]) x 0.0552]/22.5); endothelial function measured by brachial artery reactivity testing; and cardiac autonomic system activity measured by heart rate variability. RESULTS: The TM group had beneficial changes (measured as mean +/- SD) in adjusted systolic blood pressure (-3.4 +/- 2.0 vs 2.8 +/- 2.1 mm Hg; P = .04), insulin resistance (-0.75 +/- 2.04 vs 0.52 +/- 2.84; P = .01), and heart rate variability (0.10 +/- 0.17 vs -0.50 +/- 0.17 high-frequency power; P = .07) compared with the health education group, respectively. There was no effect of brachial artery reactivity testing. CONCLUSIONS: Use of TM for 16 weeks in CHD patients improved blood pressure and insulin resistance components of the metabolic syndrome as well as cardiac autonomic nervous system tone compared with a control group receiving health education. These results suggest that TM may modulate the physiological response to stress and improve CHD risk factors, which may be a novel therapeutic target for the treatment of CHD.