Search results for "coronary circulation"
showing 10 items of 75 documents
Early detection of coronary artery flow and myocardial perfusion impairment in hypertensive patients evidenced by myocardial blush grade (MBG) and th…
2012
OBJECTIVE: In hypertensive patients with typical chest pain but absence of coronary stenosis the coronary microcirculation may be impaired, thus, our study aimed to appraise, in these subjects, the role of the coronary microcirculation, assessed by Myocardial Blush Grade (MBG) and Thrombolysis in Myocardial Infarction (TIMI) Frame Count (TFC). METHODS: A total of 95 subjects with chest pain and uninjured coronary arteries were recruited into the study: 80 subjects were hypertensive while 15 subjects were normotensive. The hypertensive subjects were divided into two subgroups: hypertensive subjects with positive scintigraphy and hypertensive subjects with negative scintigraphy. The TFC, a qu…
Physical training and hypertension have opposite effects on endothelial brain-derived neurotrophic factor expression
2013
AIMS: Changes in circulating brain-derived neurotrophic factor (BDNF) levels were reported in patients with or at risk for cardiovascular diseases associated with endothelial dysfunction, suggesting a link between BDNF and endothelial functionality. However, little is known on cardiovascular BDNF. Our aim was to investigate levels/localization, function, and relevance of cardiovascular BDNF. METHODS AND RESULTS: BDNF levels (western blotting) and localization (immunostaining) were assessed in the heart and aorta from rats with impaired (spontaneously hypertensive rats [SHR]), normal (Wistar Kyoto rats [WKY]), and improved (SHR and WKY subjected to physical training) endothelial function. BD…
The new clinical standard of integrated quadruple stress echocardiography with ABCD protocol
2018
Abstract Background The detection of regional wall motion abnormalities is the cornerstone of stress echocardiography. Today, stress echo shows increasing trends of utilization due to growing concerns for radiation risk, higher cost and stronger environmental impact of competing techniques. However, it has also limitations: underused ability to identify factors of clinical vulnerability outside coronary artery stenosis; operator-dependence; low positivity rate in contemporary populations; intermediate risk associated with a negative test; limited value of wall motion beyond coronary artery disease. Nevertheless, stress echo has potential to adapt to a changing environment and overcome its c…
Evidence of impaired coronary flow reserve and elevated microvascular resistances in a case of recurrent left apical ballooning.
2011
A 56-year old man was admitted for precordial pain associated with dyspnea and evidence of myocardial ischemia on ECG and cardiac ultrasound. His previous history included an episode of left apical ballooning five years before. At angiography, no evidence of significant epicardial coronary artery disease was manifest. Interestingly, both coronary flow reserve and the index of microvascular resistances were abnormal, showing evidence of impaired microvascular function. This is the first report providing direct evidence of microvascular dysfunction in a patient with (recurrent) apical ballooning.
Arrhythmias and inhibition of noradrenaline uptake caused by tricyclic antidepressants and chlorpromazine on the isolated perfused rabbit heart
1975
1. Isolated rabbit hearts were perfused with a modified Tyrode solution containing noradrenaline in concentrations increasing stepwise from 5.9 nM to 5.9 μM at 5 min intervals. This dose regime was applied twice before and once 20 min after starting perfusion with one of 9 tricyclic drugs. Ventricular rate and right atrial and ventricular tensions were recorded using the transverse method. 2. Infusions of noradrenaline evoked ventricular arrhythmias in hearts perfused with amitriptyline 4.8 μM, chlorpromazine 5.0 μM, desipramine 5.0 μM, dibenzepine 34.7 μM, doxepin 4.7 μM, imipramine 4.7 μM, noxiptiline 9.1 μM and opipramole 9.2 μM. The incidence of arrhythmias increased with the concentrat…
Analysis of myocardial perfusion or myocardial function for detection of regional myocardial abnormalities. An echocardiographic multicenter comparis…
2007
Background: Echocardiography based myocardial perfusion imaging and regional wall motion analysis are used for evaluation of coronary artery disease and regional myocardial abnormalities. Aim: This study sought to compare myocardial contrast echocardiography (MCE) and 2D echocardiography with regard to interobserver variability and detection of regional myocardial abnormalities. Methods: In 70 patients evenly distributed between three ejection fraction groups based on biplane cineventriculography (>55%, 35-55%, <35%), unenhanced and contrast enhanced 2D echocardiography and myocardial contrast echocardiography (MCE; SonoVue (R); Bracco) were performed. Regional watt motion and myocardial pe…
Prognostic value of exercise myocardial scintigraphy in patients with coronary chronic total occlusions.
2010
Objectives: To evaluate the prognostic value of exercise myocardial scintigraphy in patients undergoing incomplete revascularization by means of percutaneous coronary intervention (PCI) with at least a residual chronic total occlusion (CTO) left untreated. Methods: Of 569 consecutive patients with multivessel disease undergoing myocardial scintigraphy after incomplete revascularization by PCI between March 1997 and December 2004, 126 (79% male, 64 ± 10 years) with ≥ 1 residual CTO fulfilled the eligibility criteria and entered in the study. Hard events defined as cardiac death and myocardial infarction, soft events defined as incidence of unstable angina and PCI procedures, and their compos…
Effect of theophylline on calcium exchangeability in ventricular myocardium.
1976
The effects of theophylline on contractile force and myocardial calcium exchangeability were studied in isolated, electrically driven Langendorff perfused guinea-pig hearts. Following a 30-min exposure to 45Ca, total cellular calcium and 45Ca activity were measured in right ventricular samples. "Nontoxic" theophylline concentrations (5 x 10(-5) -10(-3) g/ml) which augmented contractile force without producing arrhythmias or contractures had no effect on total tissue calcium and did not alter the size of the fraction of cellular calcium exchangeable under steady-state conditions. A "toxic" concentration of theophylline (2 x 10(-3) g/ml) induced contractures and increased the amount of exchan…
Microvascular perfusion 1 week and 6 months after myocardial infarction by first-pass perfusion cardiovascular magnetic resonance imaging
2006
To characterise the evolution of myocardial perfusion during the first 6 months after myocardial infarction by first-pass perfusion cardiovascular magnetic resonance imaging (CMR) and determine its significance.Prospective cohort design.Single-centre study in a teaching hospital in Spain.40 patients with a first ST-elevation myocardial infarction, single-vessel disease and thrombolysis in myocardial infarction (TIMI) grade 3 flow (stent in 33 patients) underwent rest and low-dose dobutamine CMR 7 (SD 1) and 184 (SD 11) days after infarction. Microvascular perfusion was assessed at rest by visual assessment and quantitative analysis of first-pass perfusion CMR. Of the 640 segments, 290 segme…
Correlation between longitudinal strain analysis and coronary microvascular dysfunction in patients with heart failure with preserved ejection fracti…
2020
Objective: The aim of this study was to evaluate in patients with microvascular angina and heart failure with preserved ejection fraction, the speckle-tracking echocardiography, and longitudinal myocardial strain to evaluate the possible presence of alterations in heart failure with preserved ejection fraction patients compared with a control population. We also investigated the correlation between the longitudinal strain analysis and the TIMI frame count after coronary angiography. Methods: Our study was performed on a population 41 patients with microvascular angina that underwent coronary angiography and speckle-tracking echocardiography. We divided the sample into two categories: patien…