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Low flow state in coronary arteries

Alvaro F Vargas Pelaez, Zhaohui Gao, Tariq A Ahmad, Urs A Leuenberger, David N Proctor, Stephan R Maman, Matthew D Muller
Myocardial oxygen supply and demand mismatch is fundamental to the pathophysiology of ischemia and infarction. The sympathetic nervous system, through α-adrenergic receptors and β-adrenergic receptors, influences both myocardial oxygen supply and demand. In animal models, mechanistic studies have established that adrenergic receptors contribute to coronary vascular tone. The purpose of this laboratory study was to noninvasively quantify coronary responses to adrenergic receptor stimulation in humans. Fourteen healthy volunteers (11 men and 3 women) performed isometric handgrip exercise to fatigue followed by intravenous infusion of isoproterenol...
May 2016: Physiological Reports
Michael S Lee, Evan Shlofmitz, Richard Shlofmitz, Sheila Sahni, Brad Martinsen, Jeffrey Chambers
OBJECTIVES: The ORBIT II trial reported excellent outcomes in patients with severely calcified coronary lesions treated with orbital atherectomy. Severe calcification of the left main (LM) artery represents a complex coronary lesion subset. This study evaluated the safety and efficacy of coronary orbital atherectomy to prepare severely calcified protected LM artery lesions for stent placement. METHODS: The ORBIT II trial was a prospective, multicenter clinical trial that enrolled 443 patients with severely calcified coronary lesions in the United States...
September 2016: Journal of Invasive Cardiology
V A Sandrikov, T Yu Kulagina, I V Arkhipov, A S Krylov, A M Yatchenko, Yu N Petrova, E Yu Van
The paper analyzes the study of the myocardium in patients with coronary artery disease to identify new predictors of reduction of myocardial contractility. Research carried out on the basis of transthoracic echocardiography and transesophageal on Vivid 7 unit and Vivid-E9 with multifrequency array sensor (3.5-5.5 MHz) by method with the obligatory registration ofstandard ECG. All studies in the form of static and moving images (3-5 cardiocycles Cine-loop) is stored in workstation memory Echopac 7 (GE Vingmed Ultrasound, USA)...
September 2015: Anesteziologiia i Reanimatologiia
Rong Bing, Andy S C Yong, Harry C Lowe
Accurate assessment of the left main coronary artery (LMCA) is critical in determining treatment strategies and delineating revascularization options to improve prognosis. There has been an evolution in invasive techniques that allow detailed assessment of both function and anatomy. As technologies advance, there is an increasing amount of evidence supporting the use of percutaneous coronary intervention for the LMCA. This state-of-the-art paper provides an in-depth exploration of intravascular ultrasound, fractional flow reserve, and optical coherence tomography...
October 2015: JACC. Cardiovascular Interventions
L Hasib, A K Lundberg, H Zachrisson, J Ernerudh, L Jonasson
OBJECTIVE: Regulatory T cells (Tregs) are considered atheroprotective, and low levels have been associated with the acute coronary syndrome (ACS), particularly non-ST elevation (NSTE)-ACS. However, the functional properties as well as homeostasis of Tregs are mainly unknown in coronary artery disease (CAD). Here, we investigated the composition and functional properties of naïve (n) and memory (m)Tregs in patients with NSTE-ACS and in patients 6-12 months post-ACS. METHODS: Based on the expression of CD25, FOXP3, CD127, CD45RA, CD39 and CTLA-4, Treg subsets were defined by flow cytometry in whole blood or isolated CD4(+) T cells...
January 2016: Journal of Internal Medicine
Eric K W Poon, Umair Hayat, Vikas Thondapu, Andrew S H Ooi, Muhammad Asrar Ul Haq, Stephen Moore, Nicolas Foin, Shengxian Tu, Cheng Chin, Jason P Monty, Ivan Marusic, Peter Barlis
Percutaneous coronary intervention (PCI) has shown a high success rate in the treatment of coronary artery disease. The decision to perform PCI often relies on the cardiologist's visual interpretation of coronary lesions during angiography. This has inherent limitations, particularly due to the low resolution and two-dimensional nature of angiography. State-of-the-art modalities such as three-dimensional quantitative coronary angiography, optical coherence tomography and invasive fractional flow reserve (FFR) may improve clinicians' understanding of both the anatomical and physiological importance of coronary lesions...
August 2015: Coronary Artery Disease
Haruhiko Machida, Isao Tanaka, Rika Fukui, Yun Shen, Takuya Ishikawa, Etsuko Tate, Eiko Ueno
Multidetector coronary computed tomography (CT), which is widely performed to assess coronary artery disease noninvasively and accurately, provides excellent image quality. Use of electrocardiography (ECG)-controlled tube current modulation and low tube voltage can reduce patient exposure to nephrotoxic contrast media and carcinogenic radiation when using standard coronary CT with a retrospective ECG-gated helical scan. Various imaging techniques are expected to overcome the limitations of standard coronary CT, which also include insufficient spatial and temporal resolution, beam-hardening artifacts, limited coronary plaque characterization, and an inability to allow functional assessment of coronary stenosis...
July 2015: Radiographics: a Review Publication of the Radiological Society of North America, Inc
E Tutal, M Erkmen Uyar, S Uyanik, Z Bal, O Guliyev, S K Toprak, O Ilhan, S Sezer, M Haberal
OBJECTIVE: The resistance of blood to flow is called plasma viscosity. Increased blood viscosity has been described in patients with coronary and peripheral arterial disease. In this study, we evaluated the influence of clinical and laboratory findings on plasma viscosity in renal transplant recipients. METHODS: Eighty-one kidney transplant recipients (37.8 ± 11.3 years old, 50.38 ± 16.8 months post-transplantation period, 27 female) with normal graft functions were enrolled...
May 2015: Transplantation Proceedings
Javier Moral-Vico, Jaume Barallat, Llibertat Abad, Rosa Olivé-Monllau, Francesc Xavier Muñoz-Pascual, Amparo Galán Ortega, F Javier del Campo, Eva Baldrich
In this work we report on the production of a low cost microfluidic device for the multiplexed electrochemical detection of magneto bioassays. As a proof of concept, the device has been used to detect myeloperoxidase (MPO), a cardiovascular biomarker. With this purpose, two bioassays have been optimized in parallel onto magnetic beads (MBs) for the simultaneous detection of MPO endogenous peroxidase activity and quantification of total MPO. Since the two bioassays produced signals of different magnitude for each concentration of MPO tested, two detection strategies have been compared, which entailed registering steady state currents (Iss) under substrate flow, and measuring the peak currents (Ip) produced in a stopped flow approach...
July 15, 2015: Biosensors & Bioelectronics
Tetsuma Kawaji, Hiroki Shiomi, Takeshi Morimoto, Ryusuke Nishikawa, Mariko Yano, Hirooki Higami, Junichi Tazaki, Masao Imai, Naritatsu Saito, Takeru Makiyama, Satoshi Shizuta, Koh Ono, Takeshi Kimura
BACKGROUND: Multifunction cardiogram (MCG) is a computer-enhanced, resting electrocardiogram analysis developed to detect hemodynamically relevant coronary artery disease (CAD). Based on data from previous studies suggesting excellent diagnostic accuracy in detecting CAD, MCG (approved by the Food and Drugs Administration) received a Current Procedure Terminology (CPT) code in 2010 in United States. However, there is no previous study validating MCG by using fractional flow reserve (FFR) as the reference standard...
September 2015: Annals of Noninvasive Electrocardiology
Jörn F Dopheide, Pascal Knopf, Geraldine C Zeller, Markus Vosseler, Nico Abegunewardene, Thomas Münzel, Christine Espinola-Klein
Monocytes and dendritic cells (DC) produce tumour necrosis factor (TNF)α during inflammatory processes, but secrete interleukin (IL)-10 simultaneously in order to balance the pro-inflammation. In the present study, we investigated the expression of TNFα and IL-10 by monocytes and DC in patients with a poor cardiovascular prognosis after 10 years. Peripheral blood monocytes were isolated from 30 patients with coronary artery disease (CAD) with stable angina pectoris (SAP), or with an acute coronary syndrome (ACS)...
April 2015: Inflammation
Mohammad Nurulqadr Jameel, Qingsong Hu, Jianyi Zhang
Decrease of ambient oxygen level has been used in myocytes culture experiments in examining the responsiveness to stress secondary to hypoxia. However, none of these studies measure the myocytes oxygenation levels resulting in ambiguity as to whether there is insufficient oxygen delivery. This study examined the hypothesis that at a basal myocardial work state, adequate myocyte oxygenation would be maintained until extremely low arterial pO2 levels were reached. Myocyte pO2 values in normal dogs were calculated from the myocardial deoxymyoglobin (Mb- δ) levels using (1)H-spectroscopy (MRS) and were normalized to Mb-δ obtained after complete LAD occlusion...
2014: PloS One
Yinghua Tao, Guang-Hong Chen, Timothy A Hacker, Amish N Raval, Michael S Van Lysel, Michael A Speidel
PURPOSE: Dynamic CT myocardial perfusion imaging has the potential to provide both functional and anatomical information regarding coronary artery stenosis. However, radiation dose can be potentially high due to repeated scanning of the same region. The purpose of this study is to investigate the use of statistical iterative reconstruction to improve parametric maps of myocardial perfusion derived from a low tube current dynamic CT acquisition. METHODS: Four pigs underwent high (500 mA) and low (25 mA) dose dynamic CT myocardial perfusion scans with and without coronary occlusion...
July 2014: Medical Physics
M Malvè, A M Gharib, S K Yazdani, G Finet, M A Martínez, R Pettigrew, J Ohayon
The purpose of the present study was to determine whether in vivo bifurcation geometric factors would permit prediction of the risk of atherosclerosis. It is worldwide accepted that low or oscillatory wall shear stress (WSS) is a robust hemodynamic factor in the development of atherosclerotic plaque and has a strong correlation with the local site of plaque deposition. However, it still remains unclear how coronary bifurcation geometries are correlated with such hemodynamic forces. Computational fluid dynamics simulations were performed on left main (LM) coronary bifurcation geometries derived from CT of eight patients without significant atherosclerosis...
January 2015: Annals of Biomedical Engineering
Michael S Lee, Tae Yang, George Adams
PURPOSE: To compare the acute outcomes of orbital atherectomy treatment in diabetic vs. non-diabetic patients with peripheral artery disease (PAD). METHODS: The CONFIRM registry series contained 1842 diabetic patients (1111 men; mean age 70.6±10.2 years) with 2819 lesions and 1247 non-diabetic patients (732 men; mean age 72.9±10.7 years) with 1885 lesions. The composite rate of procedure-related complications, including dissection, perforation, slow flow, vessel closure, spasm, embolism, and thrombus formation, was analyzed for the diabetic and non-diabetic groups...
April 2014: Journal of Endovascular Therapy
Maarit Hallikainen, Janne Halonen, Jussi Konttinen, Harri Lindholm, Piia Simonen, Markku J Nissinen, Helena Gylling
BACKGROUND: For decades in Finland, intensive population strategies and preventive activities have been used to lower the risk of atherosclerotic coronary heart disease (CHD). Lifestyle changes, with the emphasis on diet, play an important role in preventive strategies. The aim of this study was to evaluate arterial stiffness and endothelial function in asymptomatic free-living adults and to relate the results to CHD risk factors and lifestyle habits with the emphasis on diet. METHODS: Ninety-four asymptomatic participants were recruited by advertisements in four large companies and two research institutes employing mainly office workers...
2013: Nutrition & Metabolism
Javaid Iqbal, Ruth Andrew, Nicholas L Cruden, Christopher J Kenyon, Katherine A Hughes, David E Newby, Patrick W F Hadoke, Brian R Walker
CONTEXT: Mineralocorticoid receptor (MR) antagonists have beneficial effects in patients with heart failure and myocardial infarction, often attributed to blocking aldosterone action in the myocardium. However, binding of aldosterone to MR requires local activity of the enzyme 11β-hydroxysteroid dehydrogenase type 2 (11β-HSD2), which inactivates cortisol to cortisone and thereby prevents receptor occupancy by cortisol. In vivo activity of 11β-HSD2 and potential occupancy of MR by cortisol in human heart have not been quantified...
March 2014: Journal of Clinical Endocrinology and Metabolism
Eulália Pereira, Nuno Bettencourt, Nuno Ferreira, Andreas Schuster, Amedeo Chiribiri, João Primo, Madalena Teixeira, Lino Simões, Adelino Leite-Moreira, José Silva-Cardoso, Vasco Gama, Eike Nagel
INTRODUCTION: Cardiac magnetic resonance myocardial perfusion imaging (CMR-MPI) is considered a state-of-the-art non-invasive modality for ischemia detection but its additive value in a multiple-test strategy in patients with suspected coronary artery disease (CAD) is not fully validated. We aimed to evaluate CMR-MPI integration with exercise treadmill test (ETT) for the diagnostic workup of patients with suspected CAD, having invasive fractional flow reserve (FFR) as reference standard...
October 9, 2013: International Journal of Cardiology
Sanjeev Bhattacharyya, Omar Chehab, Rajdeep Khattar, Guy Lloyd, Roxy Senior
AIMS: Stress echocardiography (SE) is one of the leading modalities for the assessment of coronary artery disease and dynamic valvular heart disease. A wide range of different techniques have been established. There are no data which identify how current techniques have been integrated into clinical practice. METHODS AND RESULTS: An electronic questionnaire was devised to identify SE practice in five core areas: service demographics, indications, methods, reporting, and adverse events...
February 2014: European Heart Journal Cardiovascular Imaging
Gabrielle J Pennings, Justine Siegwald, Andy S C Yong, Leonard Kritharides, Harry C Lowe
Platelets and leukocytes play an important role in atherosclerotic plaque progression. Determining the activation state of both the platelet and leukocyte population at the lesion site has become increasingly of interest. A novel thrombus aspiration catheter, the Thrombuster II (Kaneka Medical Products, Osaka, Japan), has recently been introduced into clinical practice, and is finding rapidly increasing use. This catheter is capable of local blood collection within the coronary tree, but to our knowledge has not previously been validated to demonstrate lack of platelet activation...
April 2014: Journal of Thrombosis and Thrombolysis
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