Abstract:
:The rate of QT adaptation to abrupt changes in pacing rate was studied in seven patients with newly diagnosed complete heart block with a ventricular escape rate of less than 40 beats.min-1. Their median age was 70 (range 36-84) years, and none was taking any cardioactive medication known to affect the QT interval. From a baseline pacing rate of 50 or 110 beats.min-1 the ventricular rate was increased or decreased to a new level. The time taken for the ventricular paced QT interval to complete 90% of the change secondary to the change in rate was found to be 136(16) s (mean(SEM] when the rate was increasing and 189(25) s when the rate was decreasing (p less than 0.01). This time interval was independent of the magnitude of the rate change and the baseline heart rate from which the change occurred. Furthermore, the time course of QT adaptation was found to be exponential and was characterised by a time constant of 49.1(2.2) s when the rate was increasing and 60.4(2.0) s when the rate was decreasing (p less than 0.01). It is concluded that QT measurements in response to a change in pacing rate should take into account the time dependent nature of QT changes.
journal_name
Cardiovasc Resjournal_title
Cardiovascular researchauthors
Lau CP,Freedman AR,Fleming S,Malik M,Camm AJ,Ward DEdoi
10.1093/cvr/22.1.67subject
Has Abstractpub_date
1988-01-01 00:00:00pages
67-72issue
1eissn
0008-6363issn
1755-3245journal_volume
22pub_type
杂志文章abstract:OBJECTIVES:While it is probable that the cerebrovascular spasm which occurs after subarachnoid haemorrhage results from the action of haemoglobin, the mechanism of that process remains unclear. These studies were thus designed to test the hypothesis that the action of oxyhaemoglobin results from the iron-catalyzed form...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:
更新日期:1995-10-01 00:00:00
abstract:AIMS:Pulmonary hypertension (PH) is a devastating condition for which no disease-modifying therapies exist. PH is recognized as proliferative disease of the pulmonary artery (PA). In the experimental newborn calf model of hypoxia-induced PH, adventitial fibroblasts in the PA wall exhibit a heightened replication index....
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/cvs194
更新日期:2012-08-01 00:00:00
abstract:OBJECTIVE:To study the effect of cardiac contraction on left coronary artery pressure-flow relations at different vascular volumes and to compare these relations in the beating heart with those in the heart arrested in systole and diastole. METHODS:Maximally vasodilated, Tyrode perfused, rabbit hearts (n = 6) with an ...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1016/s0008-6363(98)00119-9
更新日期:1998-10-01 00:00:00
abstract:AIMS:The aim of this study was to explore meprinα-mediated transactivation of the epidermal growth factor receptor (EGFR) and reactive oxygen species (ROS) production in macrophages. METHODS AND RESULTS:Accelerated atherosclerotic lesions were established by administration of a high-fat diet in apolipoprotein E-defici...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/cvs369
更新日期:2013-03-01 00:00:00
abstract::Peptidyl-prolyl cis-trans-isomerases are a highly conserved family of immunophilins. The three peptidyl-prolyl cis-trans-isomerase subfamilies are cyclophilins, FK-506-binding proteins, and parvulins. Peptidyl-prolyl cis-trans-isomerases are expressed in multiple human tissues and regulate different cellular functions...
journal_title:Cardiovascular research
pub_type: 杂志文章,评审
doi:10.1093/cvr/cvv096
更新日期:2015-06-01 00:00:00
abstract::In this review, we summarize current knowledge on the genetics of coronary artery disease, based on 10 years of genome-wide association studies. The discoveries began with individual studies using 200K single nucleotide polymorphism arrays and progressed to large-scale collaborative efforts, involving more than a 100 ...
journal_title:Cardiovascular research
pub_type: 历史文章,杂志文章,评审
doi:10.1093/cvr/cvy084
更新日期:2018-07-15 00:00:00
abstract:OBJECTIVE:Ghrelin, the endogenous ligand of growth hormone secretagogue receptor (GHS-R), acts on the pituitary and the hypothalamus to stimulate the release of growth hormone (GH) and promotes appetite and adiposity. It has also been reported to increase myocardial contractility, induce vasodilation, and protect again...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1016/j.cardiores.2004.01.024
更新日期:2004-06-01 00:00:00
abstract:OBJECTIVE:Although aldosterone has been implicated in the pathogenesis of cardiac hypertrophy and heart failure, its cellular mechanism of action on cardiomyocyte function is not yet completely elucidated. This study was designed to investigate the effect of aldosterone on calcium channel expression and cardiomyocyte c...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1016/j.cardiores.2005.05.009
更新日期:2005-08-01 00:00:00
abstract::The effects of adrenaline on kinetically-distinct compartments of exchangeable calcium in the spontaneously-beating perfused rat heart were investigated under steady-state conditions using a 45Ca2+ outflow technique together with a nonlinear least-squares curve fitting procedure and 51Cr-EDTA to monitor the loss of fr...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/17.2.88
更新日期:1983-02-01 00:00:00
abstract:OBJECTIVE:We investigated the efficacy of nicaraven in reducing myocardial as well as coronary endothelial preservation-reperfusion (P/R) injury. METHODS:In experiment I, isolated rat hearts were mounted on a Langendorff (L) apparatus to estimate the baseline cardiac function. Group 1, 8- and 12-h storage in histidine...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1016/s0008-6363(96)00268-4
更新日期:1997-03-01 00:00:00
abstract:OBJECTIVE:The aim was to test the hypothesis that in normal humans angiotensin II would stimulate local release of noradrenaline under basal conditions or during a sympathetic stimulus provided by lower body negative pressure (LBNP). METHODS:Nine healthy volunteers received intra-arterial infusions of angiotensin II, ...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/28.5.663
更新日期:1994-05-01 00:00:00
abstract:OBJECTIVE:Impairment of endothelium-dependent relaxation is related to dyslipidemia and may be an early marker for atherosclerosis in angiographically smooth arteries. The aim of the present study was to relate preoperative serum lipids to endothelium-dependent relaxation in internal mammary arteries of patients underg...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1016/s0008-6363(97)00081-3
更新日期:1997-06-01 00:00:00
abstract:OBJECTIVE:Temporal effects of prolonged hypoxaemia and reoxygenation, on the systemic pulmonary and mesenteric circulations in newborn piglets, were investigated. METHODS:Two groups [control (n = 5), hypoxaemic (n = 7)] of 1-3 day old anaesthetised piglets were instrumented with ultrasound flow probes placed to measur...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1016/s0008-6363(98)00080-7
更新日期:1998-08-01 00:00:00
abstract::There is mounting interest in the use of the monophasic action potential for electrophysiological investigation of regional myocardial ischaemia. There is, however, no systematic study of the relation between the changes in monophasic action potential and regional myocardial blood flow. In this study monophasic action...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/20.10.740
更新日期:1986-10-01 00:00:00
abstract:OBJECTIVE:Anisotropic conduction characteristics, which may be expressed as the ratio of conduction velocities in the longitudinal (Vlong) and transverse (Vtrans) fibre directions, have been shown to stabilise reentry and favour the induction of sustained, uniform ventricular tachycardia. The aim of this study was to i...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1016/s0008-6363(96)88593-2
更新日期:1995-03-01 00:00:00
abstract:AIMS:Both mitochondria and nitric oxide (NO*) contribute to cardioprotection by ischaemic preconditioning (IPC). IPC causes mild uncoupling of mitochondria via uncoupling proteins (UCPs) and the adenine nucleotide translocase (ANT), and mild uncoupling per se is cardioprotective. Although electrophilic lipids are known...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/cvn323
更新日期:2009-05-01 00:00:00
abstract:AIMS:Atrial fibrillation (AF) is a major risk factor for cardio-embolic stroke. Anticoagulant drugs are effective in preventing AF-related stroke. However, the high frequency of anticoagulant-associated major bleeding is a major concern. This study sought to identify new targets to develop safer antithrombotic therapie...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/cvw049
更新日期:2016-06-01 00:00:00
abstract:OBJECTIVES:Epidemiological evidence in humans suggests that intrauterine growth retardation is associated with an increased risk of hypertension and coronary heart disease in later life. To begin to understand the mechanisms involved, we developed and exploited a rat model of intrauterine growth retardation to assess p...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1016/s0008-6363(00)00167-x
更新日期:2000-11-01 00:00:00
abstract:OBJECTIVE:The aim was to correlate the relative abilities of amiodarone, lignocaine, and penticainide in suppressing ventricular tachyarrhythmias in response to coronary artery occlusion with their relative abilities to prolong ventricular functional refractory periods and to reduce intraventricular conduction velociti...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/26.11.1116
更新日期:1992-11-01 00:00:00
abstract::The afterload dependency of relaxation rate was reappraised in isolated canine hearts both in isovolumic and isobaric contractions by using the reliable exponential method in which the asymptote LV pressure (P chi) is variable. This method provided a closer correlation (r = 0.999 +/- 0.001) between the measured LV pre...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/19.10.649
更新日期:1985-10-01 00:00:00
abstract::Congenital coronary artery anomalies are of major significance in clinical cardiology and cardiac surgery due to their association with myocardial ischaemia and sudden death. Such anomalies are detectable by imaging modalities and, according to various definitions, their prevalence ranges from 0.21 to 5.79%. This cons...
journal_title:Cardiovascular research
pub_type: 杂志文章,评审
doi:10.1093/cvr/cvv251
更新日期:2016-02-01 00:00:00
abstract:OBJECTIVE:This study aimed to examine the effects of adenovirus-mediated expression of p35, a baculovirus gene, on apoptosis induced by hypoxia/reoxygenation (H/R) in cardiomyocytes. METHODS:Neonatal rat cardiomyocytes were infected with recombinant adenoviral vectors expressing p35 (Ad2/CMVp35) or no transgene (Ad2/C...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1016/s0008-6363(02)00412-1
更新日期:2002-08-01 00:00:00
abstract:AIMS:Although the use of drug-eluting stents (DESs) has been shown to limit neointima hyperplasia, currently available DESs may adversely affect re-endothelialization. To evaluate whether a novel gene silencer pyrrole-imidazole (PI) polyamide targeting transforming growth factor (TGF)-beta1 is a candidate agent for the...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/cvn355
更新日期:2009-03-01 00:00:00
abstract:AIMS:Cardiovascular research requires complex and functionally intact experimental models. Due to major differences in the cellular and subcellular composition of the myocardium between species, the use of human heart tissue is highly desirable. To enhance the experimental use of the human myocardium, we established me...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/cvr259
更新日期:2012-01-01 00:00:00
abstract::Functional studies in extrarenal non-epithelial cells such as smooth muscle cells and easily accessible human lymphocytes have demonstrated that aldosterone not only produces classical genomic effects, but also rapid non-genomic effects on transmembrane electrolyte movements. These involve the activation of the Na+/H+...
journal_title:Cardiovascular research
pub_type: 杂志文章,评审
doi:
更新日期:1995-02-01 00:00:00
abstract:OBJECTIVE:Washed platelets have been shown to protect isolated buffer perfused rat hearts from injury and dysfunction following ischaemia-reperfusion. This study was designed to investigate whether platelet glutathione redox cycle contributes to the protective effect of platelets. METHODS:Isolated rat hearts were perf...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/28.10.1586
更新日期:1994-10-01 00:00:00
abstract::The cardiac SR Ca(2+)-ATPase (SERCA2a) regulates intracellular Ca(2+)-handling and thus, plays a crucial role in initiating cardiac contraction and relaxation. SERCA2a may be modulated through its accessory phosphoprotein phospholamban or by direct phosphorylation through Ca(2+)/calmodulin dependent protein kinase II ...
journal_title:Cardiovascular research
pub_type: 杂志文章,评审
doi:10.1016/s0008-6363(02)00694-6
更新日期:2003-01-01 00:00:00
abstract:OBJECTIVE:Air bubbles entering the coronary artery may have harmful effects on cardiac function. From the physical point of view it is the relatively high surface tension of the blood-air interface which causes bubbles to trap in small vessels. The aim of the present study was to reduce depression of myocardial functio...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1016/s0008-6363(97)00063-1
更新日期:1997-06-01 00:00:00
abstract::Myocardial lactate content and simultaneous evolution of a lactate arteriovenous gradient associated with incomplete obstruction of the left coronary bed were studied in dog hearts. Samples of blood were taken from a peripheral artery and the coronary sinus; transmural samples of myocardial tissue were obtained from t...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/16.10.552
更新日期:1982-10-01 00:00:00
abstract::Mechanical stress signals transmitted through the heart walls during hemodynamic loading are sensed by the myocytes, which respond with changes in contractile performance and gene expression. External forces play an important role in physiological heart development and hypertrophy, but disruption of the well-balanced ...
journal_title:Cardiovascular research
pub_type: 杂志文章,评审
doi:10.1016/j.cardiores.2007.03.029
更新日期:2008-03-01 00:00:00