Abstract:
BACKGROUND:The incidence of syncope exhibits a daily pattern with more occurrences in the morning, possibly as a result of influences from the endogenous circadian system and/or the daily pattern of behavioral/emotional stimuli. This study tested the hypothesis that the circadian system modulates cardiovascular responses to postural stress, leading to increased susceptibility to syncope at specific times of day. METHODS AND RESULTS:Twelve subjects underwent a 13-day in-laboratory protocol in which subjects' sleep-wake cycles were adjusted to 20 hours for 12 cycles. A 15-minute tilt-table test (60° head-up) was performed ≈4.5 hours after scheduled awakening in each cycle so that 12 tests in each subject were distributed evenly across the circadian cycle. Of 144 tests, signs/symptoms of presyncope were observed in 21 tests in 6 subjects. These presyncope events displayed a clear circadian rhythm (P=0.028) with almost all cases (17/21) occurring in the half of the circadian cycle corresponding to the biological night (10:30 pm to 10:30 am). Significant circadian rhythms were also observed in hemodynamic and autonomic function markers (blood pressure, heart rate, epinephrine, norepinephrine, and indices of cardiac vagal tone) that may underlie the circadian rhythm of presyncope susceptibility. CONCLUSIONS:The circadian system affects cardiovascular responses to postural stress, resulting in greater susceptibility to presyncope during the night. This finding suggests that night-shift workers and people with disrupted sleep at night may have greater risk of syncope as a result of their exposure to postural stress during the biological night.
journal_name
Circulationjournal_title
Circulationauthors
Hu K,Scheer FA,Laker M,Smales C,Shea SAdoi
10.1161/CIRCULATIONAHA.110.943019subject
Has Abstractpub_date
2011-03-08 00:00:00pages
961-70issue
9eissn
0009-7322issn
1524-4539pii
CIRCULATIONAHA.110.943019journal_volume
123pub_type
杂志文章相关文献
CIRCULATION文献大全abstract:BACKGROUND:The incidence of cardiovascular disease (CVD), coronary heart disease (CHD), and type 2 diabetes mellitus (T2DM) has not been well defined in persons with the metabolic syndrome (at least 3 of the following: abdominal adiposity, low HDL cholesterol, high triglycerides, hypertension, and impaired fasting gluc...
journal_title:Circulation
pub_type: 杂志文章,多中心研究
doi:10.1161/CIRCULATIONAHA.105.539528
更新日期:2005-11-15 00:00:00
abstract:BACKGROUND:Cardiac myosin-binding protein C (cMyBP-C) is a sarcomeric protein that dynamically regulates thick-filament structure and function. In constitutive cMyBP-C knockout (cMyBP-C(-/-)) mice, loss of cMyBP-C has been linked to left ventricular dilation, cardiac hypertrophy, and systolic and diastolic dysfunction,...
journal_title:Circulation
pub_type: 杂志文章
doi:10.1161/CIRCULATIONAHA.111.089219
更新日期:2012-09-04 00:00:00
abstract:BACKGROUND:Perioperative management of patients with complete mixing of pulmonary and systemic blood centers on approximately equating pulmonary (Qp) and systemic (Qs) blood flow (Qp/Qs approximately 1). This empirically derived target is opposed by theoretical studies advocating a target Qp/Qs well below 1. We studied...
journal_title:Circulation
pub_type: 杂志文章
doi:10.1161/01.cir.100.21.2198
更新日期:1999-11-23 00:00:00
abstract::The International Liaison Committee on Resuscitation has initiated a near-continuous review of cardiopulmonary resuscitation science that replaces the previous 5-year cyclic batch-and-queue approach process. This is the first of an annual series of International Consensus on Cardiopulmonary Resuscitation and Emergency...
journal_title:Circulation
pub_type: 杂志文章,实务指引,评审
doi:10.1161/CIR.0000000000000541
更新日期:2017-12-05 00:00:00
abstract:BACKGROUND:Activated fibroblasts (myofibroblasts) play a critical role in cardiac fibrosis; however, their origin in the diseased heart remains unclear, warranting further investigation. Recent studies suggest the contribution of bone marrow fibroblast progenitor cells (BM-FPCs) in pressure overload-induced cardiac fib...
journal_title:Circulation
pub_type: 杂志文章
doi:10.1161/CIRCULATIONAHA.117.027889
更新日期:2017-09-05 00:00:00
abstract:BACKGROUND:Reducing sympathetic output to the heart from the neuraxis can protect against ventricular arrhythmias. The purpose of this study was to assess the value of thoracic epidural anesthesia (TEA) and left cardiac sympathetic denervation (LCSD) in the management of ventricular arrhythmias in patients with structu...
journal_title:Circulation
pub_type: 杂志文章,多中心研究
doi:10.1161/CIRCULATIONAHA.109.929703
更新日期:2010-06-01 00:00:00
abstract::Between 1976 and 1982, 413 consecutive patients underwent valvular replacement with a bioprosthesis. Aortic valve replacement was performed in 240 patients, mitral valve replacement in 132, and multiple-valve replacement in 41. Four prostheses were employed: Carpentier-Edwards porcine (n = 336), Angel-Shiley porcine (...
journal_title:Circulation
pub_type: 杂志文章
doi:
更新日期:1989-09-01 00:00:00
abstract:BACKGROUND:Anisotropy creates nonuniformity in electrical propagation and may contribute to the occurrence of unidirectional conduction block and reentry. We describe the characteristics of reentrant tachycardia in a 2D layer of anisotropic ventricular myocardium. METHODS AND RESULTS:A Langendorff-perfused epicardial ...
journal_title:Circulation
pub_type: 杂志文章
doi:10.1161/01.cir.102.21.2650
更新日期:2000-11-21 00:00:00
abstract:BACKGROUND:Autoimmune mechanisms have been implicated in the pathogenesis of chronic ongoing myocarditis. To investigate this relation, we used an A/J mouse model inoculated with coxsackievirus B3 and determined whether myocarditis would be transferred to normal hearts that were heterotopically transplanted. METHODS A...
journal_title:Circulation
pub_type: 杂志文章
doi:10.1161/01.cir.94.12.3348
更新日期:1996-12-15 00:00:00
abstract::Two-dimensional suprasternal notch echocardiography was performed in 1033 patients, ages 1 day to 18 years. For the long-axis suprasternal notch view, the transducer was positioned in the suprasternal notch and angled to obtain a plane passing between the right nipple and left scapular tip. In this view, the entire ao...
journal_title:Circulation
pub_type: 杂志文章
doi:10.1161/01.cir.63.1.165
更新日期:1981-01-01 00:00:00
abstract:BACKGROUND:Our aim was to compare the electron-beam CT (EBCT) features of coronary arteries in heart transplant recipients with those of biplane coronary angiography and intracoronary ultrasound (ICUS). METHODS AND RESULTS:We examined 112 heart transplant recipients (25 female; age, 17 to 69 years; median, 52 years) 1...
journal_title:Circulation
pub_type: 临床试验,杂志文章
doi:10.1161/01.cir.101.17.2078
更新日期:2000-05-02 00:00:00
abstract:BACKGROUND:Considering the controversial results published in the literature concerning associations between human leukocyte antigens (HLA) and rheumatic fever (RF), the purpose of the present study was to investigate by means of cosegregation analysis the participation of HLA genes in susceptibility to RF. METHODS AN...
journal_title:Circulation
pub_type: 杂志文章
doi:10.1161/01.cir.89.1.138
更新日期:1994-01-01 00:00:00
abstract:BACKGROUND:The main goal of the initial treatment of ST-segment elevation myocardial infarction is prompt reperfusion of the infarct-related artery. The value of pretreatment with clopidogrel before primary percutaneous coronary intervention is currently unclear. METHODS AND RESULTS:Studies were retrieved through MEDL...
journal_title:Circulation
pub_type: 杂志文章,评审
doi:10.1161/CIRCULATIONAHA.107.749531
更新日期:2008-10-28 00:00:00
abstract::Contrary to opinions generally accepted in the past, CHD is very common in both African-American men and women, with incidence rates approaching those of US Caucasians. Higher prevalence of hypertension, diabetes, cigarette smoking, and obesity all contribute to the high level of CHD in African-Americans. Additional r...
journal_title:Circulation
pub_type: 杂志文章
doi:10.1161/01.cir.83.4.1474
更新日期:1991-04-01 00:00:00
abstract:BACKGROUND:Cigarette smoking has been recognized as an important risk factor for cardiovascular disease in men and women. Whether the increased risk results from an atherogenic effect of smoking is still debated. We examined the relation between cigarette smoking and atherosclerotic changes in the abdominal aorta. MET...
journal_title:Circulation
pub_type: 杂志文章
doi:10.1161/01.cir.88.5.2156
更新日期:1993-11-01 00:00:00
abstract::Reactive oxygen species such as the superoxide anion (.O2-) have recently been implicated as important agents involved in causing cell death in the setting of myocardial ischemia and reperfusion. When superoxide anion is involved in ischemic injury the administration of superoxide dismutase (SOD) may limit infarct siz...
journal_title:Circulation
pub_type: 杂志文章
doi:10.1161/01.cir.75.6.1237
更新日期:1987-06-01 00:00:00
abstract::Cardiovascular disease continues to be the leading cause of death among women in the United States. One of the barriers to improving cardiovascular disease outcomes in women is the lack of reliable, effective screening modalities. Breast arterial calcification has emerged as a potential risk stratification tool. Local...
journal_title:Circulation
pub_type: 杂志文章
doi:10.1161/CIRCULATIONAHA.118.038092
更新日期:2019-02-19 00:00:00
abstract:BACKGROUND:Patients with a non-ST-elevation acute coronary syndrome and prior CABG are at high risk of a recurrent ischemic event despite aspirin therapy. This trial investigated the potential benefit of secondary prevention with warfarin. METHODS AND RESULTS:In a double-blind randomized trial, 135 patients with unsta...
journal_title:Circulation
pub_type: 临床试验,杂志文章,随机对照试验
doi:10.1161/01.cir.103.25.3069
更新日期:2001-06-26 00:00:00
abstract:BACKGROUND:MicroRNAs (miRs) participate in many cardiac pathophysiological processes, including ischemia/reperfusion (I/R)-induced cardiac injury. Recently, we and others observed that miR-494 was downregulated in murine I/R-injured and human infarcted hearts. However, the functional consequence of miR-494 in response ...
journal_title:Circulation
pub_type: 杂志文章
doi:10.1161/CIRCULATIONAHA.110.964684
更新日期:2010-09-28 00:00:00
abstract::Experience with percutaneous transluminal coronary angioplasty (PTCA) of multiple vessels was reviewed to assess short-term outcome and long-term results. PTCA of multiple vessels was performed in 100 of the initial 500 patients (20%) who underwent PTCA at the Medical College of Virginia between July 1979 and August 1...
journal_title:Circulation
pub_type: 杂志文章
doi:10.1161/01.cir.72.6.1314
更新日期:1985-12-01 00:00:00
abstract:BACKGROUND:We have developed a new measure of myocardial viability, the water-perfusable tissue index (PTI), which is calculated from transmission, C15O, and H2(15)O positron emission tomography (PET) data sets. It is defined as the proportion of the total anatomical tissue within a given region of interest (ROI) that ...
journal_title:Circulation
pub_type: 杂志文章
doi:10.1161/01.cir.86.1.167
更新日期:1992-07-01 00:00:00
abstract::The hypothesis tested in this study was that despite the presence of severe postischemic myocardial dysfunction ("stunning"), the extraction and subsequent intracellular washout of thallium 201 should be preserved as long as irreversible sarcolemmal membrane injury was avoided. To produce myocardial stunning, 19 open-...
journal_title:Circulation
pub_type: 杂志文章
doi:10.1161/01.cir.81.5.1622
更新日期:1990-05-01 00:00:00
abstract:BACKGROUND:We previously reported beneficial effects of pentoxifylline, a xanthine-derived agent known to inhibit the production of tumor necrosis factor-alpha, in patients with idiopathic dilated cardiomyopathy treated with diuretics, digoxin, and ACE inhibitors. Since then, 3 large clinical trials showed important cl...
journal_title:Circulation
pub_type: 临床试验,杂志文章,随机对照试验
doi:10.1161/01.cir.103.8.1083
更新日期:2001-02-27 00:00:00
abstract:BACKGROUND:The myocardial velocity gradient (MVG) is a recent index of regional myocardial function derived from endocardial and epicardial velocities obtained by tissue Doppler imaging (TDI). This index might be useful for discriminating between physiological and pathological left ventricular hypertrophy (LVH) and for...
journal_title:Circulation
pub_type: 杂志文章
doi:10.1161/01.cir.0000012943.91101.d7
更新日期:2002-04-02 00:00:00
abstract::Fifty-four Japanese patients with occlusive thromboaortopathy (OTAP), including four males, were classified according to evidence of complications attributed to OTAP at the time when the diagnosis was established: Group I, uncomplicated OTAP with or without the involvement of the pulmonary artery. Group II, mono-compl...
journal_title:Circulation
pub_type: 杂志文章
doi:10.1161/01.cir.57.1.27
更新日期:1978-01-01 00:00:00
abstract:BACKGROUND:Restenosis after initial, successful percutaneous transluminal coronary angioplasty (PTCA) is due to fibrocellular proliferation. METHODS AND RESULTS:The present study focused on the nature of fibrocellular tissue in humans by use of immunocytochemical techniques. Four hearts (five coronary arteries) were i...
journal_title:Circulation
pub_type: 杂志文章
doi:10.1161/01.cir.83.4.1327
更新日期:1991-04-01 00:00:00
abstract::The myocardial uptake of 125I- and 131I-antimyosin monoclonal antibody Fab in experimental myocarditis in BALB/c mice induced by encephalomyocarditis virus was studied. The biodistribution of 125I-antimyosin demonstrated that the highest ratio of radioactivity appears in the heart of infected mice on day 14 (the ratio...
journal_title:Circulation
pub_type: 杂志文章
doi:10.1161/01.cir.79.2.400
更新日期:1989-02-01 00:00:00
abstract:BACKGROUND:Physical activity is associated with lower risk of cardiovascular disease, but the mechanisms are uncertain. Hemostatic and inflammatory markers have been linked with risk of cardiovascular disease. We therefore examined the relationship between physical activity and hemostatic and inflammatory variables. M...
journal_title:Circulation
pub_type: 杂志文章
doi:10.1161/hc1502.107117
更新日期:2002-04-16 00:00:00
abstract:BACKGROUND:Gene-nutrient interactions affecting high-density lipoprotein cholesterol (HDL-C) concentrations may contribute to the interindividual variability of the cardiovascular disease risk associated with dietary fat intake. Hepatic lipase (HL) is a key determinant of HDL metabolism. Four polymorphisms in linkage d...
journal_title:Circulation
pub_type: 杂志文章
doi:10.1161/01.cir.0000036597.52291.c9
更新日期:2002-10-29 00:00:00
abstract::Two hundred forty-five patients with variant angina were followed for an average of 80.5 months (range, 36-184 months). Survival rate at 1, 3, 5, and 10 years was 98%, 97%, 97%, and 93%, respectively. Survival rate without myocardial infarction at 1, 3, 5, and 10 years was 86%, 85%, 83%, and 81%, respectively. By univ...
journal_title:Circulation
pub_type: 杂志文章
doi:10.1161/01.cir.78.1.1
更新日期:1988-07-01 00:00:00