ST-elevation myocardial infarction (STEMI) results from acute thrombotic obstruction of a coronary artery. Percutaneous coronary intervention (PCI) is the treatment of choice to restore blood flow. The incidence of guidewire-induced reopening of the infarct-related coronary artery (IRA) and its association with post-procedural TIMI flow and long-term mortality were assessed. Angiograms ...

Myocardial bridging (MB) is a congenital anomaly characterized by systolic compression of the tunnelled arterial segment. MB may cause myocardial ischaemia due to abnormal coronary blood flow. We report a case of MB in which transthoracic Doppler echocardiography was used to evaluate the long-term effect of beta-blocker therapy on abnormal ...

coronary microvascular dysfunction may underlie the high cardiovascular risk associated with chronic kidney disease (CKD), but the effects of CKD on coronary microvasculature function remain uncertain. we assessed myocardial blood flow changes in mild-to-moderate CKD and analyzed the association between creatinine clearance (CrCl) and peak myocardial blood flow and coronary ...

The adenine nucleotide hypothesis postulates that the ATP released from red blood cells is broken down to ADP and AMP in coronary capillaries and that ATP, ADP, and AMP act on purinergic receptors on the surface of capillary endothelial cells. Purinergic receptor activation initiates a retrograde conducted vasodilator signal to ...

We sought to assess coronary flow parameters in patients with isolated coronary artery ectasia (CAE) as compared to subjects with normal coronaries. Consecutively, we enrolled 30 patients with ectasia of the left anterior descending (LAD) coronary artery (study group), and 10 subjects with normal coronaries (control group). All patients underwent ...

Coronary artery disease (CAD) is the leading cardiovascular cause of death, and in men, endogenous testosterone concentrations are inversely related to the extent and severity of CAD. Testosterone is known to affect a number of risk factors for CAD and has effects on vascular tone, vasoreactivity and blood flow of ...

OBJECTIVES: This study investigated the association between morphological characteristics of culprit atheromatic lesions as assessed by optical coherence tomography and Thrombolysis In Myocardial Infarction (TIMI) flow grade after thrombolysis in patients with ST-segment elevation myocardial infarction (STEMI). BACKGROUND: Although several variables have been found to predict coronary flow after thrombolysis ...

Background: Coronary sinus (CS) flow in response to a provocative stress has been used as a surrogate measure of coronary flow reserve, and velocity-encoded cine (VEC) magnetic resonance imaging (MRI) is an established technique for measuring CS flow. In this study, the cold pressor test (CPT) was used to measure ...

The endothelial glycocalyx is the negatively charged, gel-like mesh residing at the luminal side of the vascular endothelium and forming the interface between the flowing blood and the vessel wall. The vast majority of glycocalyx volume resides in the microcirculation, particularly in the capillaries. Intravital microscopic observations of capillaries in ...

Background: We sought to assess coronary flow parameters in patients with isolated coronary artery ectasia (CAE) as compared to subjects with normal coronaries. Methods: Consecutively, we enrolled 30 patients with ectasia of the left anterior descending (LAD) coronary artery (study group), and 10 subjects with normal coronaries (control group). All ...

It has been reported that imbibing red wine increases coronary blood flow reserve acutely. In the absence of changes in coronary driving pressure, any increases in coronary blood flow reserve should occur through a decrease in capillary resistance, which in turn is determined by capillary dimensions and whole-blood viscosity. Since ...

BACKGROUND: Recently we reported a decline of circulating myeloid (m) and plasmacytoid (p) dendritic cells (DCs) in patients with coronary artery disease (CAD). This study also determined the total blood DC numbers and focused on effects of extent (one vs. three-vessel disease) and type (stable vs. unstable) of CAD, and ...

OBJECTIVE: During intraaortic balloon inflation, blood volume is displaced toward the heart (V(tip)), traveling retrograde in the descending aorta, passing by the arch vessels, reaching the aortic root (V(root)), and eventually perfusing the coronary circulation (V(cor)). V(cor) leads to coronary flow augmentation, one of the main benefits of the intraaortic ...

Mice are now commonly used as models of human cardiovascular diseases and conditions, but it is challenging to measure blood flow velocity in small vessels such as coronary arteries. Accordingly, we have developed a method using a 2 mm diameter 20 MHz pulsed Doppler probe applied to the chest of ...

Coronary angiography is limited in assessing the hemodynamic significance of a coronary lesion or the state of the coronary microcirculation. Noninvasive transthoracic (TTE) and transesophageal (TEE) Doppler echocardiography have been used to measure coronary blood flow velocity and coronary flow reserve and thus the physiology of the coronary vasculature (normal, ...

Vascular endothelium is covered with an extensive mesh of glycocalyx constituents, which acts like an effective barrier up to several micrometers thick that shields the luminal surface of the vasculature from direct exposure to flowing blood. Many studies report that various enzymatic and pharmaceutical challenges are able to increase glycocalyx ...

Functional severity of coronary stenosis is often assessed using diagnostic parameters. These parameters are evaluated from the combined pressure and/or flow measurements taken at the site of the stenosis. However, when there are functional collaterals operating downstream to the stenosis, the coronary flow-rate increases, and the pressure in the stenosed ...

Slow coronary flow (SCF) is the phenomenon of slow progression of angiographic contrast in the coronary arteries in the absence of stenosis in the epicardial vessels in some patients presenting with chest pain. There are no definite treatment modalities for patients with SCF. Our aim was to investigate the efficacy ...

BACKGROUND: International guidelines recommend the routine use of oxygen in the initial treatment of myocardial infarction, yet it is uncertain what effect this might have on physiologic and clinical outcomes. METHODS: We undertook a systematic search of Medline, Cochrane Database of Systematic Reviews, EMBASE, and CINHAL using the key words ...

BACKGROUND: Inducing stable maximal coronary hyperemia is essential for measurement of fractional flow reserve (FFR). We evaluated the efficacy of the intracoronary (IC) continuous adenosine infusion method via a microcatheter for inducing maximal coronary hyperemia. METHODS: In 43 patients with 44 intermediate coronary lesions, FFR was measured consecutively by IC ...

OBJECTIVES: The aim of this study was to evaluate the effects of alcohol septal ablation (ASA) on coronary blood flow in symptomatic hypertrophic obstructive cardiomyopathy (HOCM) using cardiac MR (CMR) coronary flow measurements. Background CMR flow mapping enables quantification of coronary blood flow in a noninvasive way. Both left ventricular ...

OBJECTIVE: This study was conducted to investigate the potential role of intravascular oxidative stress in inexplicable episodes of coronary artery spasm (CAS) during coronary angiography (CAG). DESIGN AND METHODS: Serial patients with stable angina scheduled for routine CAG were prospectively evaluated. Patients with clinical evidence of variant angina were excluded. ...

Mice are now commonly used as models of human cardiovascular diseases and conditions, but it is challenging to measure blood flow velocity in small vessels such as coronary arteries. Accordingly, we have developed a method using a 2 mm diameter 20 MHz pulsed Doppler probe applied to the chest of ...

OBJECTIVES: We evaluated the impairment of endothelium-dependent and endothelium-independent coronary blood flow reserve after administration of intracoronary acetylcholine and adenosine, and its association with hypertensive cardiac disease. INTRODUCTION: Coronary blood flow reserve reduction has been proposed as a mechanism for the progression of compensated left ventricular hypertrophy to ventricular dysfunction. ...

Results in animals suggest favourable coronary vasomotor actions of isoflavones; however, the effects of isoflavones on the human coronary circulation have not been determined. In the present study, we therefore investigated the effects of short-term isoflavone-intact soya protein ingestion on basal coronary arterial tone and stimulated vasoreactivity and blood flow ...

BACKGROUND: Calcitonin gene-related peptide (CGRP) and substance P (SP) play counter-regulatory roles in coronary flow. This study is to assess whether effects of CGRP and SP are gender-specific. METHODS: Langendorff-perfused hearts were used to compare coronary flow rates among 119 wild-type, alpha-CGRP and SP receptor knockout mice under various perfusion ...

To investigate the effects of Xuefu Zhuyu Oral Liquid, a compound traditional Chinese herbal medicine for resolving stagnation, on hemorheology in the patients with blood-stasis syndrome due to coronary disease and their relationship with human platelet antigen-3 (HPA-3) polymorphism of membrane glycoprotein IIb (GPIIb). Thirty-two patients with blood-stasis syndrome due ...

Several studies have suggested that mediastinitis is a strong predictor for poor long-term survival after coronary artery bypass surgery (CABG). In those studies, several conventional wound-healing techniques were used. Previously, we have shown no difference in long-term survival between CABG patients with topical negative pressure (TNP)-treated mediastinitis and CABG patients ...

The endogenous nucleoside adenosine has profound tissue protective effects in situations of ischaemia or inflammation. Animal studies have shown that various drugs can activate this protective mechanism by interfering with the metabolism of adenosine. Translation of this concept to the clinical arena is hampered by the difficulties encountered in measuring ...

BACKGROUND: Canine and porcine hearts have been widely used to investigate diagnoses, interventions, and surgical therapies for ischemic heart disease. Dogs and pigs are known to vary with regard to the anatomic distribution of their coronary arteries. However, the mechanisms of these differences and the differing phasic coronary blood flow ...

Endovascular stents reside in a dynamic flow environment and yet the impact of flow on arterial drug deposition after stent-based delivery is only now emerging. We employed computational fluid dynamic modeling tools to investigate the influence of luminal flow patterns on arterial drug deposition and distribution. Flow imposes recirculation zones ...

Blood flow is distributed through the heart muscle via a system of vessels forming the coronary circulation. The perfusion of the myocardium can be hampered by atherosclerosis creating localized obstructions in the epicardial vessels or by microvascular disease. In early stages of the disease, these impediments to blood flow are ...

This thesis explores two possible ways of detecting soft plaque present in the coronary arteries, using CTA imagery. The coronary arteries are vessels that supply oxidized blood to the cardiac muscle and are thus important for the proper functioning of heart. Cholesterol or reactive oxygen species from cigarette smoke and ...

BACKGROUND AND AIMS: Aging is a dominant process that alters vascular stiffness, endothelial function and coronary flow regulation. The objective of our work was to assess simultaneously the elastic properties of the descending aorta and coronary flow velocity reserve (CFR) during the same transesophageal echocardiography (TEE) in elderly patients. METHODS: ...

OBJECTIVES: To assess the effect of intravenous sodium nitroprusside and nitroglycerin on coronary blood flow distal to a severe coronary artery stenosis. METHODS: Parameters of coronary arteries and coronary blood flow were measured distally to the stenosis during nitroprusside and nitroglycerin infusions in a dose producing a 25% decrease in ...

Introduction: It is well known that hemoglobin is a scavenger of nitric oxide (NO). The present study used a canine model to test the hypothesis that acute normovolemic hemodilution (ANH) affects NO-mediated coronary vasodilation. METHODS: Studies were performed in 18 open-chest, anesthetized dogs. In Series 1, the contribution of endogenous ...

Daidzein is a very good candidate for treating cardio-cerebrovascular diseases, but its poor oral absorption and bioavailability limit its curative efficacy. In this work, daidzein-loaded solid lipid nanoparticles (SLNs) with PEGylated phospholipid as stabilizer were successfully prepared by hot homogenization method. SLNs showed the mean particle size 126+/-14 nm with ...

Fractional flow reserve (FFR) provides an objective physiological evaluation of stenosis severity. A technique that can measure FFR using only angiographic images would be a valuable tool in the cardiac catheterization laboratory. To perform this, the diseased blood flow can be measured with a first pass distribution analysis and the ...

In patients with coronary artery disease (CAD), coronary blood flow is usually impaired due to imbalanced vasoactive substances such as nitric oxide (NO) and endothelin-1 (ET-1). The study was designed to test the effects of Ginkgo biloba extract (GBE) on the distal left anterior descending coronary artery (LAD) blood flow ...

BACKGROUND: The temporal behavior of the coronary microcirculation in acute myocardial infarction may affect outcome. Diastolic deceleration time and early systolic flow reversal derived from coronary artery blood flow velocity patterns reflect microcirculatory function. OBJECTIVES: To assess left anterior descending coronary artery flow velocity patterns using Doppler transthoracic echocardiography after ...

The aim of the study was to validate a newly-designed epicardial coronary artery Doppler probe and test its detection of changes in coronary blood flow velocity. Left anterior descending (LAD) coronary blood flow and flow velocity were evaluated in four pigs with a pericoronary transit time flow (TTF) probe and ...

Relatively limited and conflicting data are available on the effects of cardiac resynchronization therapy (CRT) on coronary blood flow (CBF). To investigate changes in the left anterior descending coronary artery (LAD) flow under different CRT pacing modes by means of transthoracic Doppler echocardiography (TTE). Twenty-two responders to CRT (67+/-11 years) ...

OBJECTIVES: The study's objective was to evaluate a novel two-dimensional ultrasound imaging modality termed "blood flow imaging" (BFI) for intraoperative assessment of blood flow patterns in coronary anastomoses. The BFI modality extends color Doppler imaging (CDI) with information on flow direction and velocity that is not limited by angle dependency ...

OBJECTIVE: It has previously been observed that coronary diameter may increase following relief of flow-limiting obstruction. Flow mediated dilatation (FMD) is a fundamental adaptive mechanism for arteries, which is dependent on intact endothelial function. We thus aimed to characterize whether the degree of this flow-mediated dilatation was related to risk ...

Advancing age decreases endothelial function; accordingly, it alters the physiological regulation of coronary blood flow. Ginkgo biloba extract (GBE) has well-documented anti-ageing effects. However, little is yet known about the pharmacological actions of GBE on endothelial dysfunction and coronary blood flow in healthy elderly adults. We designed the study to ...

We describe a new approach that combines several techniques to allow abnormal electrical and calcium activity to be visualized within hypoperfused myocardial tissue. A flexible microcannula was inserted into the left anterior descending artery of Langendorff perfused rat hearts, an air-tight seal between the coronary artery and the cannula was ...

The treatment of coronary artery disease (CAD) is clinically measured by monitoring changes in venous lipids and inflammatory markers. There is currently no established quantified relationship between coronary flow reserve and markers of inflammatory CAD. A total of 120 men and women underwent quantified measurement of coronary blood flow using ...

Starting out from a brief description of the determinants of coronary blood flow (perfusion, pressure, extravascular compression, autoregulation, metabolic regulation, endothelium-mediated regulation and neurohumoral regulation) the present review highlights the overwhelming importance of metabolic regulation such that coronary blood flow is increased at increased heart rate under physiological circumstances and ...

Coronary blood flow in one (circumflex) branch of the left coronary artery increases when an adjacent (left anterior descending [LAD]) branch is occluded for periods of between 1 min and 25 min. To examine the possible role of the myocardial release of vasoactive substances in such 'compensatory blood flow' increase ...

The atherosclerosis modifications at the vascular level are evidentiated early by diminishing the blood flow mediated vasodilatation, thickening of the arterial wall and the appearance since childhood of the aortic fibrose plates. Their evolution is determined mainly by the atherosclerotic dislipidemia. The maximum risk for atherosclerosis and coronary disease appears ...