Abstract:
BACKGROUND:Myocardial ischemia is considered to be a possible stimulus for development of the coronary collateral circulation. We therefore hypothesized that chronic reduction of myocardial oxygen demand to lessen ischemia would attenuate coronary collateral development over an 8-week period using left circumflex coronary artery (LCx) ameroid-induced constriction in pigs. METHODS AND RESULTS:Collateral development was assessed by myocardial blood flow (radioactive microspheres) and left ventricular regional function (sonomicrometer dimension gauges). beta-Adrenoceptor blockade with propranolol (160 or 320 mg b.i.d.p.o.) was initiated in 15 animals 1 day after surgery. Compared with 16 untreated animals, beta-adrenoceptor antagonism was documented in the treated group by 1) pharmacological stimulation with isoproterenol, 2) physiological stimulation during graded treadmill exercise, and 3) repeated long-term biotelemetry recordings of oxygen demand (heart rate and blood pressure) and regional myocardial function. In addition to pharmacological and physiological verification of beta-blockade, biotelemetry showed that, compared with the untreated animals, propranolol significantly reduced the daily number, individual duration, and severity of events representing myocardial dysfunction. This suggests that in the beta-blocked group, little if any ischemia was present throughout the first 5 weeks when collateral growth occurs. Transmural myocardial blood flow (expressed as a ratio of flow in the LCx region to the nonoccluded region of the left ventricle) and systolic wall thickening in the LCx region were determined at rest and during treadmill exercise (240 beats per minute) 31-38 days (5 weeks) and 60-67 days (8 weeks) after surgery. Propranolol was withdrawn 3 days before flow and function determinations and was resumed immediately after testing. Blood flow ratios at 5 weeks decreased similarly from rest to exercise in the untreated (0.83 +/- 0.04 to 0.60 +/- 0.05, p less than 0.05) and beta-blockade group (0.82 +/- 0.09 to 0.57 +/- 0.10, p less than 0.05). Systolic wall thickening from rest to exercise was attenuated to the same degree in the untreated (59 +/- 6% to 38 +/- 6%, p less than 0.05) and beta-blockade group (50 +/- 8% to 30 +/- 5%, p less than 0.05). Similar flow and function responses were observed in both groups at 8 weeks. CONCLUSIONS:We conclude that growth and development of the coronary collateral circulation measured functionally during exercise at 90% of maximal heart rate is unrelated to the extent and duration of myocardial ischemia in this model.
journal_name
Circulationjournal_title
Circulationauthors
Symons JD,Pitsillides KF,Longhurst JCdoi
10.1161/01.cir.86.2.660subject
Has Abstractpub_date
1992-08-01 00:00:00pages
660-71issue
2eissn
0009-7322issn
1524-4539journal_volume
86pub_type
杂志文章相关文献
CIRCULATION文献大全abstract:BACKGROUND:In the minutes to days after myocardial infarction, endogenous lysis of an occlusive coronary arterial thrombus occurs in most subjects. Compared with those in whom thrombolysis does not occur, those with antegrade flow in the infarct artery have improved left ventricular performance, less left ventricular d...
journal_title:Circulation
pub_type: 杂志文章
doi:10.1161/01.cir.88.3.935
更新日期:1993-09-01 00:00:00
abstract::Aortic root motion was studied in 24 normal volunteers at rest and during the Valsalva maneuver, isometric exercise, and amyl nitrite inhalation. In addition root motion was correlated with the stroke volumes determined at cardiac catheterization in 24 patients. The root has distinct systolic movement, the amplitude a...
journal_title:Circulation
pub_type: 杂志文章
doi:10.1161/01.cir.53.6.947
更新日期:1976-06-01 00:00:00
abstract:BACKGROUND:Although lipoprotein(a) (Lp[a]) is a risk factor for atherosclerosis, no study has documented the effects of Lp(a) on angiogenesis. In this study, we examined collateral formation in peripheral arterial disease (PAD) model in Lp(a) transgenic mice. In addition, we examined the feasibility of gene therapy by ...
journal_title:Circulation
pub_type: 杂志文章
doi:10.1161/01.cir.0000012146.07240.fd
更新日期:2002-03-26 00:00:00
abstract::More accurate characterization of coronary artery lesions is needed for evaluation of short and long-term interventions in coronary disease. A method of segmental artery analysis has been developed to maximize the information obtained from coronary arteriograms. Coronary lesions are traced from two projected, perpendi...
journal_title:Circulation
pub_type: 杂志文章
doi:10.1161/01.cir.55.2.329
更新日期:1977-02-01 00:00:00
abstract:BACKGROUND:Platelet deposition and aggregation are central to the pathogenesis of ischemic complications of acute coronary syndromes (ACS). Pharmacodynamic effects of the platelet glycoprotein IIb/IIIa antagonist eptifibatide have been delineated in healthy subjects but not in patients with ACS. We assessed effects of ...
journal_title:Circulation
pub_type: 临床试验,杂志文章,随机对照试验
doi:10.1161/hc2901.093500
更新日期:2001-07-24 00:00:00
abstract:BACKGROUND:Modeling of the time-[1-(11)C]acetate activity curve assumes a constant concentration of labeled tricarboxylic acid cycle intermediates and associated metabolites, such as glutamate and aspartate, which may, however, decrease in short-term hibernating myocardium. METHODS AND RESULTS:In 12 anesthetized pigs,...
journal_title:Circulation
pub_type: 杂志文章
doi:10.1161/01.cir.97.10.1009
更新日期:1998-03-17 00:00:00
abstract::The acute hemodynamic effects of dobutamine and nitroprusside were compared in 19 patients with low output cardiac failure. At dosage levels yielding similar increases in cardiac index (12 patients), nitroprusside resulted in significantly lower arterial systolic and wedge pressures and did not increase heart rate sug...
journal_title:Circulation
pub_type: 杂志文章
doi:10.1161/01.cir.56.6.918
更新日期:1977-12-01 00:00:00
abstract:BACKGROUND:Aging results in vascular stiffening and an increase in the velocity of the pressure wave as it travels down the aorta. Increased aortic pulse wave velocity (aPWV) has been associated with mortality in clinical but not general populations. The objective of this investigation was to determine whether aPWV is ...
journal_title:Circulation
pub_type: 杂志文章
doi:10.1161/CIRCULATIONAHA.104.483628
更新日期:2005-06-28 00:00:00
abstract:BACKGROUND:The mainstay of treatment for atrial fibrillation (AF) remains pharmacological; however, catheter ablation has increasingly been used over the last decade. The relative merits of each strategy have not been extensively studied. METHODS AND RESULTS:We conducted a randomized multicenter comparison of these 2 ...
journal_title:Circulation
pub_type: 杂志文章,多中心研究,随机对照试验
doi:10.1161/CIRCULATIONAHA.108.772582
更新日期:2008-12-09 00:00:00
abstract:BACKGROUND:Long-term beta-adrenergic blockade does not appear to be associated with drug-induced training in patients with congestive heart failure (CHF); whether exercise training can increase peak aerobic capacity in patients with CHF who are treated with beta-adrenergic blockers is currently unknown. METHODS AND RE...
journal_title:Circulation
pub_type: 临床试验,杂志文章
doi:10.1161/01.cir.95.7.1764
更新日期:1997-04-01 00:00:00
abstract:BACKGROUND:Fortilin, a recently characterized nuclear antiapoptotic factor structurally distinct from inhibitor of apoptosis proteins (IAPs) and Bcl-2 family member proteins, has been suggested to be involved in cell survival and regulation of apoptosis within the cardiovascular system. In this continued investigation,...
journal_title:Circulation
pub_type: 杂志文章
doi:10.1161/01.cir.0000047675.86603.eb
更新日期:2003-01-07 00:00:00
abstract::Between 1973 and 1983, 90 patients with tricuspid atresia underwent the Fontan operation at the Mayo Clinic. Operative mortality was 12% overall and decreased to 7% during the second 5 year period. At postoperative follow-up of 65 patients (1 to 10 years, mean 4), 50 (86%) of 58 present survivors were in excellent con...
journal_title:Circulation
pub_type: 杂志文章
doi:
更新日期:1985-09-01 00:00:00
abstract::We examined the temporal kinetics of onset and offset of the cardiac electrophysiologic effects of orally administered amiodarone in chronically instrumented, unsedated adult dogs (n = 8). Right atrial (RA), atrioventricular nodal (AVN), and right ventricular (RV) effective refractory period (ERP), and AVN functional ...
journal_title:Circulation
pub_type: 杂志文章
doi:10.1161/01.cir.72.6.1380
更新日期:1985-12-01 00:00:00
abstract:BACKGROUND:The mechanisms linking obesity to hypertension have not been established, but sodium retention and excessive sympathetic tone are key contributors. The natriuretic peptides are important regulators of sodium homeostasis and neurohormonal activation, raising the possibility that obese individuals have an impa...
journal_title:Circulation
pub_type: 杂志文章
doi:10.1161/01.CIR.0000112582.16683.EA
更新日期:2004-02-10 00:00:00
abstract::To assess myocardial infarction quantitatively in 15 mm thick transverse sections of the canine heart in vivo we utilized a new technique, positron emission transaxial tomography (PETT) and cyclotron-produced 11C-palmitate (11C-P) injected intravenously. Results were compared to regional myocardial creatine phosphokin...
journal_title:Circulation
pub_type: 杂志文章
doi:10.1161/01.cir.55.1.66
更新日期:1977-01-01 00:00:00
abstract:BACKGROUND:The aim of this prospective, randomized study was to examine whether additional school exercise lessons would result in improved peak oxygen uptake (primary end point) and body mass index-standard deviation score, motor and coordinative abilities, circulating progenitor cells, and high-density lipoprotein ch...
journal_title:Circulation
pub_type: 杂志文章,随机对照试验
doi:10.1161/CIRCULATIONAHA.109.865808
更新日期:2009-12-01 00:00:00
abstract:BACKGROUND:Functional benefit in heart failure due to idiopathic dilated cardiomyopathy has been observed after beta-blockade, but improvement in survival has not been established in a large-scale randomized trial. This was the main objective of the Cardiac Insufficiency Bisoprolol Study (CIBIS). METHODS AND RESULTS:S...
journal_title:Circulation
pub_type: 临床试验,杂志文章,多中心研究,随机对照试验
doi:10.1161/01.cir.90.4.1765
更新日期:1994-10-01 00:00:00
abstract:BACKGROUND:Exposure to risk factors such as hypertension or hypercholesterolemia decreases the bioavailability of endothelium-derived nitric oxide (NO) and impairs endothelium-dependent vasodilation. Recently, a circulating endogenous NO synthase inhibitor, asymmetric dimethylarginine (ADMA), has been detected in human...
journal_title:Circulation
pub_type: 杂志文章
doi:10.1161/01.cir.99.9.1141
更新日期:1999-03-09 00:00:00
abstract::The relationship between fasting plasma cholesterol and triglyceride concentrations and the frequency and extensiveness of coronary artery disease (CAD) was studied in 496 subjects evaluated for chest pain by coronary arteriography at The Methodist Hospital. One hundred six of the patients had no CAD while 390 had 25%...
journal_title:Circulation
pub_type: 杂志文章
doi:10.1161/01.cir.56.5.875
更新日期:1977-11-01 00:00:00
abstract::To determine the evolution of amyloid heart disease, 28 patients with familial amyloid polyneuropathy (FAP) were studied by echocardiography. The incidence and degree of the abnormalities were correlated with the neurologic disabilities, duration of the illness, and age in cross-sectional studies. Serial studies were ...
journal_title:Circulation
pub_type: 杂志文章
doi:10.1161/01.cir.73.2.249
更新日期:1986-02-01 00:00:00
abstract:BACKGROUND:Retrospective studies in dialysis patients have reported increased survival after coronary artery bypass (CAB) compared with coronary artery stenting and PTCA. The purpose of this study was to compare the long-term outcome of renal transplant recipients after stent, PTCA, or CAB with or without internal mamm...
journal_title:Circulation
pub_type: 杂志文章
doi:10.1161/01.CIR.0000129317.12580.68
更新日期:2004-06-15 00:00:00
abstract:BACKGROUND:Radiofrequency ablation of type 1 atrial flutter (AF1) has recently evolved toward an anatomically guided procedure directed to isthmuses at the lower part of the right atrium (RA). However, different types of block at these isthmuses may be observed and potentially correlated with different late outcomes. I...
journal_title:Circulation
pub_type: 临床试验,杂志文章
doi:10.1161/01.cir.94.12.3204
更新日期:1996-12-15 00:00:00
abstract:BACKGROUND:Several mechanisms have been advanced to explain Mobitz type II atrioventricular block in the ischemically damaged His-Purkinje system. Only recently, however, has an animal model been developed to study this form of conduction defect in vivo and in vitro. METHODS AND RESULTS:Conduction defects were induced...
journal_title:Circulation
pub_type: 杂志文章
doi:10.1161/01.cir.87.4.1389
更新日期:1993-04-01 00:00:00
abstract:BACKGROUND:Recurrent arterial thrombosis and venous thrombosis are frequent complications of the antiphospholipid syndrome (APS). Patients produce anti-cardiolipin antibodies, but the role of these antibodies in thrombus formation is uncertain. This study used a unique CD-1 mouse model of thrombosis to determine whethe...
journal_title:Circulation
pub_type: 杂志文章
doi:10.1161/01.cir.94.7.1746
更新日期:1996-10-01 00:00:00
abstract::We performed transventricular pulmonary valvotomy as initial surgery in 22 consecutive patients with pulmonary atresia and intact ventricular septum who had a patent infundibulum. Nineteen patients also had placement of a central aortopulmonary shunt. All patients survived surgery, and 16 patients have had preoperativ...
journal_title:Circulation
pub_type: 杂志文章
doi:
更新日期:1990-11-01 00:00:00
abstract::Twelve consecutive patients who developed torsade de pointes (polymorphous ventricular tachycardia with marked QT prolongation, TdP) over a 4 year period were treated with intravenous injections of magnesium sulfate. In nine of the patients a single bolus of 2 g completely abolished the TdP within 1 to 5 min, and in t...
journal_title:Circulation
pub_type: 杂志文章
doi:10.1161/01.cir.77.2.392
更新日期:1988-02-01 00:00:00
abstract::Acute aortic regurgitation was created experimentally in 21 mongrel dogs to examine the relationship of the regurgitant jet to observed echocardiographic findings. The direction of the regurgitant jet was studied by echo contrast injections in the aortic root. Diastolic fluttering of the anterior mitral leaflet (AML) ...
journal_title:Circulation
pub_type: 杂志文章
doi:10.1161/01.cir.67.4.860
更新日期:1983-04-01 00:00:00
abstract:BACKGROUND:Among patients with documented stable coronary artery disease and in whom no revascularization was performed, we compared the respective values of angiographic diameter stenosis (DS) and fractional flow reserve (FFR) in predicting natural history. METHODS:The present analysis included the 607 patients from ...
journal_title:Circulation
pub_type: 临床试验,杂志文章
doi:10.1161/CIRCULATIONAHA.117.028782
更新日期:2018-04-03 00:00:00
abstract:BACKGROUND:Mildly oxidized LDL (moxLDL) is thought to play a role in atherogenesis. MoxLDL induces derivatization of cell proteins and triggers a variety of intracellular signaling. We aimed to investigate whether moxLDL-induced protein derivatization may influence the activity of platelet-derived growth factor recepto...
journal_title:Circulation
pub_type: 杂志文章
doi:10.1161/hc4001.097179
更新日期:2001-10-09 00:00:00
abstract::The endothelin (ET) system is comprised of 4 active ETs, with ET-1 being the predominant isoform in the cardiovascular system. Because of the potent vasoconstricting and mitogenic effects of ET-1 and its involvement in various cardiovascular diseases, blockade of the ET receptor has received considerable attention. ET...
journal_title:Circulation
pub_type: 杂志文章,评审
doi:10.1161/01.CIR.0000094397.19932.78
更新日期:2003-11-04 00:00:00