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The histological structure of blood vessels. Bloocd vessels are composed of three layers, called (from the lumen outwards) intima, media, and adventitia.
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Blood is pumped into the cardiac muscle through arteries called the coronary arteries. Over time, the accumulation of cholesterol, coagulation factors, and cells on the walls of these arteries causes the walls to thicken and lose their elasticity, resulting in the development of atherosclerosis. When the blood supply of the heart is diminished by a...
Citations
... They were selected based on their proven role in collagen deposition and remodeling 51 , our previously obtained experience using these cells for cardiovascular tissue engineering purposes 19,21,44,47,63,72 , and the anticipated large number of caps that can be consistently created in vitro with cells of a single donor. The human vena saphena magna is often used for coronary bypass surgeries 73 and adventitial myofibroblast as well as phenotypically altered synthetic VSMCs are deemed responsible for fibrous cap formation 74,75 . Consistent results were obtained between the two serial experiments, confirming the repeatability of the methodology. ...
A significant amount of vascular thrombotic events are associated with rupture of the fibrous cap that overlie atherosclerotic plaques. Cap rupture is however difficult to predict due to the heterogenous composition of the plaque, unknown material properties, and the stochastic nature of the event. Here, we aim to create tissue engineered human fibrous cap models with a variable but controllable collagen composition, suitable for mechanical testing, to scrutinize the reciprocal relationships between composition and mechanical properties. Myofibroblasts were cultured in 1 × 1.5 cm-sized fibrin-based constrained gels for 21 days according to established (dynamic) culture protocols (i.e. static, intermittent or continuous loading) to vary collagen composition (e.g. amount, type and organization). At day 7, a soft 2 mm ∅ fibrin inclusion was introduced in the centre of each tissue to mimic the soft lipid core, simulating the heterogeneity of a plaque. Results demonstrate reproducible collagenous tissues, that mimic the bulk mechanical properties of human caps and vary in collagen composition due to the presence of a successfully integrated soft inclusion and the culture protocol applied. The models can be deployed to assess tissue mechanics, evolution and failure of fibrous caps or complex heterogeneous tissues in general.
... Intima: Lines the lumen and is made of endothelium which is a single layer of endothelial cells and the sub-endothelial layer [11]. The latter comprises a basal lamina of loose fibroelastic connective tissue and occasional smooth muscle cells and an outermost part, the membrane elastic interna, rich in elastic fibers [12]. The endothelium has an important regulatory role in maintaining vascular tone and it also secretes vasodilator substances such as nitric oxide (NO) and vasoconstrictive substances like the endothelins and angiotensin II [13]. ...
In this review, the aim is to discuss the pathological development of vascular calcification including a brief description of arterial wall structure and function, the development of atherosclerosis, highlighting normal physiological and vascular calcification with particular emphasis on their common characteristics, critically review the recent findings implicating the role of vascular smooth muscle cells in the pathogenesis of the calcification process including the role of microRNAs in regulation of these cells phenotype as a target to control cardiovascular calcification.
... However, when stents are insufficient, coronary bypass is performed by cardiac pulmonary bypass surgery using the left internal mammary artery or saphenous vein to maintain regular nourishment of the heart. 5 AMI has found its place in the concept of acute coronary syndrome (ACS). ACS includes a group of clinical syndromes ranging from unstable angina pectoris, AMI with non-S (downward deflection immediately after ventricular contraction)-segment elevation, and T (recovery of ventricles)-segment elevation to AMI, with ST-segment submit your manuscript | www.dovepress.com ...
Purpose
Acute myocardial infarction (AMI) is the most common cause of death in the world. Comprehensive risk assessment of patients presenting with chest pain and eliminating undesirable results should decrease morbidity and mortality rates, increase the quality of life of patients, and decrease health expenditure in many countries. In this study, the advantages and disadvantages of the enzymatic and nonenzymatic biomarkers used in the diagnosis of patients with AMI are given in historical sequence, and some candidate biomarkers – hFABP, GPBB, S100, PAPP-A, RP, TNF, IL6, IL18, CD40 ligand, MPO, MMP9, cell-adhesion molecules, oxidized LDL, glutathione, homocysteine, fibrinogen, and D-dimer procalcitonin – with a possible role in the diagnosis of AMI are discussed.
Methods
The present study was carried out using meta-analyses, reviews of clinical trials, evidence-based medicine, and guidelines indexed in PubMed and Web of Science.
Results
These numerous AMI biomarkers guide clinical applications (diagnostic methods, risk stratification, and treatment). Today, however, TnI remains the gold standard for the diagnosis of AMI. Details in the text will be given of many biomarkers for the diagnosis of AMI.
Conclusion
We evaluated the advantages and disadvantages of routine enzymatic and nonenzymatic biomarkers and the literature evidence of other candidate biomarkers in the diagnosis of AMI, and discuss challenges and constraints that limit translational use from bench to bedside.
... The vessels feeding the heart contract or become clogged over time. Coronary artery bypass surgery (open heart surgery) bypasses the vessels that are occluded or constricted, using vessels taken from other parts of body: left internal mammary artery (LIMA), leg vein (saphenous vein), or arm artery (radial artery), and blood flow can be restored after the bypass (bridging) (2,3) . ...
... As noted above, since open heart surgery is performed with circulatory cardiopulmonary machinery and this nonphysiological event directly affects the endocrinal system, the primary aim of this pioneering study was to determine how the amounts of adropin, ELA, and NO change in blood samples taken at various periods in patients undergoing cardiopulmonary bypass and whether they are related to certain hemodynamic parameters (2,3) . ...
... The pursuit of additional grafts and anastomosis techniques to achieve complete revascularisation (5-6 distal anastomoses) has not proved to be an easy task (9,10). One option is the radial artery (RA), which supplies a long graft with a calibre superior to ITA but is prone to spasm and intimal hyperplasia in case of inadequate harvesting and preparation due to its muscular structure, leading to its abandonment in the early years of CABG (11). Improved harvesting and preparation finally made RA a viable option as a graft superior to SVG in terms of long-term patency (91.8% vs. 86.4%) ...
... Over the decades, graft patency has been assessed for individual grafts alone and not for CABG as an entity per se, while the dilemma of designing an optimal grafting technique bringing considerable haemodynamic improvement and graft patency remained unsolved despite the increase in worldwide research. A literature review allowed us to classify factors influencing graft patency into morphological (vessel type, graft length, and calibre) (11,15), pathophysiological (competitive flow through the native coronary artery, graft degenerative changes) (15), and surgical (technical expertise, graft harvesting and preparation, grafting design, and anastomosis technique) categories (16,17). This single-centre study analysed graft patency according to surgical technique, namely proximal and distal anastomosis type and angle. ...
The aim of the current study was to identify surgical factors associated with long-term patency of grafts used in coronary artery bypass grafting (CABG). The present study analyzed data from 127 patients who underwent CABG at our institute between 2000 and 2006 and presented for ambulatory examination and coronary computed tomography angiography evaluation of graft patency in 2016 (139.78±36.64 months post-CABG). The 127 patients received 340 grafts (2.68 grafts/patient) and 399 distal anastomoses (3.14 anastomoses/patient), 220 (55.14%) with arterial grafts and 179 (44.86%) with saphenous vein grafts. Graft patency varied according to coronary territory, proximal anastomosis type (in situ graft, composite graft, graft anastomosed to the ascending aorta), Y anastomosis angle (47.21˚ for patent arterial grafts vs. 56˚ for occluded), and distal anastomosis angle (in sequential anastomoses irrespective to graft type, 48.60˚ for patent side-to-side anastomosis vs. 53.97˚ for occluded, 65.12˚ for patent end-to-side anastomosis vs. 90.80˚ for occluded; in single end-to-side anastomosis of arterial grafts, 39.46˚ for patent and 44.94˚ for occluded). A single end-to-side anastomosis angle 60˚ or greater was associated with a 5.149 occlusion odds ratio (OR) (P<0.001) for arterial grafts. Venous grafts were not sensitive to single end-to-side anastomosis angle. In conclusion, a small anastomosis angle for proximal Y and distal anastomoses is associated with a higher long-term patency of the free graft. Radial artery grafts registered higher patency rates when anastomosed to the ascending aorta compared with composite grafting with the left internal thoracic artery, whereas in situ right internal thoracic artery (RITA) anastomosed to the right coronary territory is associated with a lower patency rate compared with free RITA used to revascularise the anterolateral or circumflex territory in composite grafting.
... Compared with the veins, the internal thoracic arteries [left internal thoracic artery (LITA) or right internal thoracic artery (RITA)] have an extremely low attrition rate with very good long-term patency rates (96.4% >15 years) (6). The anatomical imperfection of the veins and the incapacity of performing a complete revascularization using only ITAs led to the pursuit of additional grafts [the most commonly used being a. radialis (RA), followed by a. gastroepiploica dextra, a. epigastrica inferior, a. splenica, a. ulnaris, a. subscapularis, a. gastrica sinistra, and a. circumflexa femoris lateralis] and imagining new operative techniques in order to obtain a complete revascularization (5-6 distal anastomoses) using a limited number of grafts (7). ...
... Over the decades, graft patency has been assessed for individual grafts alone and not for CABG as an entity per se while the dilemma of designing an optimal grafting technique in terms of graft type, harvesting, preparation, features, configuration, or anastomoses remained unsolved despite the increase in worldwide research. Literature review allowed us to classify the factors influencing graft patency into morphological (vessel type, graft length, and caliber) (7,8), pathophysiological (competitive flow through the native coronary artery and graft degenerative changes) (8,9), and surgical (technical expertise, graft harvesting and preparation, grafting design, and anastomosis technique) (10)(11)(12). This single center study analyzed long-term graft patency according to morphological and pathophysiological factors. ...
Objective
The aim of the present study was to identify morphological and pathophysiological factors associated with long-term patency of grafts used in coronary artery bypass grafting (CABG).
Methods
A total of 127 patients who underwent CABG between 2000 and 2006 and presented for computed tomography evaluation of graft patency at 139.78±36.64 months post-CABG were analyzed. Patients received 340 grafts (2.68 grafts/patient), 399 distal anastomoses (3.14 anastomoses/patient), 220 (55.14%) performed using arterial grafts, and 179 (44.86%) using saphenous vein grafts (SVGs).
Results
Graft patency varied according to vessel type and coronary territory. Overall graft patency was 90.16% for the left internal thoracic artery (LITA), 75.55% for the right internal thoracic artery (RITA), 79.25% for the radial artery (RA), and 74.3% for the SVG. The maximum patency rate was obtained with the RA (80.65%) for the right coronary territory, RITA (92.86%) for the anterolateral territory, and SVG (82.54%) for the circumflex territory. The LITA.left anterior descending artery graft occluded in 13 (7.93%) cases, 7 due to competitive flow. The influence of graft length on patency rates after indexing to height was not significant. The target vessel degree of stenosis influenced arterial graft patency rates with an occlusion odds ratio (OR) of 3.02 when anastomosed to target vessels with <90% stenosis. Target vessel caliber also influenced patency rates with occlusion ORs of 2.63 for SVGs and 2.31 for arterial grafts when anastomosed to .1.5 mm target vessels.
Conclusion
Morphological parameters, such as graft type, target territory, target vessel caliber, and degree of stenosis, are important factors conditioning long-term graft patency.
... Coronary arteries that surround the heart and supply the myocardium with blood are constricted and obstructed over time. These constricted or obstructed vessels are bypassed by vessels taken from another body part to ensure regular blood supply to the heart [1]. Over the duration of coronary bypass surgery, since all body organs are perfused by a pump outside the body, the blood is cooled by an oxygenator and heat *Address correspondence to this author at the Cardiovascular Surgery Department, Elazig Research and Education Hospital, Health Science University, Elazig 23119; Department of Anatomy, School of Medicine, Firat University, Elazig 23119, Turkey; Tel: +90 5327856138; Fax: +90 424 2379138; E-mail: cerrah52@hotmail.com ...
... It has been known for many years that extra-corporeal circulation directly affects the endocrinal system [1]. In the present study, we examined how lactate and irisin, in addition to hemodynamic parameters, changed in the blood samples collected from coronary artery bypass patients before induction (T1), before bypass (T2), before (T3) and after (T4) removing the cross-clamp, upon admission to intensive care (T5), and at the post-operative 24 (T6) and 72 (T7) hours and whether there was a correlation between the changes in lactate and irisin levels (p: < 0.05, r: 0.98) (Fig. 3). ...
Introduction:
In coronary bypass surgery, after cardiopulmonary bypass is initiated by arterial cannulation in the ascending aorta and venous cannulation through a single vein generally in the right atrium, the process of cooling the patient is started. There is a relation between cooling the patient and irisin, which is responsible for releasing heat.
Objective:
Therefore, the main objective of the present study is to explore how irisin concentrations and some other panel of myocardium injury in patients undergoing coronary artery bypass surgery changes.
Methods:
The blood samples collected before induction (T1), before bypass (T2), before (T3) and after (T4) removing the cross-clamp, upon admission to intensive care (T5), and at the post-operative 24 (T6) and 72 (T7) hours, and whether these concentrations are correlated with lactate levels classically used in monitoring this surgery. A total of biological samples, 23 from control individuals and 105 from bypass patients (14-16 samples for each timeframe) were analyzed to determine irisin, CK-MB, TnT and BNP levels by ELISA and lactate levels by lactate assay kit. Both lactate and irisin were seen to increase gradually from the time of induction to the removal of the cross clamp. After the cross clamp was removed and the patient was started to be warmed, both parameters began to decrease gradually and were restored to normal levels on the second and third post-operative days. The increase and decrease in irisin were found correlated with lactate levels. CK-MB, TnT and BNP alteration were similar to each other.
Results:
Based on these results, it is estimated that measurement of irisin along with lactate may prove to be a useful parameter in monitoring the coronary bypass surgery and irisin may be a significant marker of hypothermia. Beside CK-MB, TnT and BNP, measurements of irisin concentration in open heart surgery may be also useful parameters for the panel of myocardium injury.
... guidelines. [4][5][6] Additionally, iloprost is the first line of treatment in occlusions seen in peripheral artery disease. 7 Iloprost (ILO) is an eicosanoid pharmaceutical agent from the prostacyclin group. ...
Aim:
Insufficient oxygen supply to organs and tissues due to reduced arterial or venous blood flow results in ischaemia, during which, although ATP production stops, AMP and adenosine continue to be produced from ATP. The fate of irisin, which causes the production of heat instead of ATP during ischaemia, is unknown. Iloprost and sildenafil are two pharmaceutical agents that mediate the resumption of reperfusion (blood supply) via vasodilatation during ischaemic conditions. Our study aimed to explore the effects of iloprost and sildenafil on irisin levels in the heart, liver and kidney tissues and whether these pharmaceutical agents had any impact on serum irisin and nitric oxide levels in rats with induced experimental myocardial ischaemia.
Methods:
The study included adult male Sprague-Dawley rats aged 10 months and weighing between 250 and 280 g. The animals were randomly allocated to eight groups, with five rats in each group. The groups were: sham (control), iloprost (ILO), sildenafil (SIL), ILO + SIL, myocardial ischaemia (MI), MI + ILO, MI + SIL and MI + ILO + SIL. The treatment protocols were implemented before inducing ischaemia, which was done by occluding the left coronary artery with a plastic ligature for 30 minutes. Following the reperfusion procedure, all rats were sacrificed after 24 hours, and their heart, liver and kidney tissues and blood samples were collected for analyses. An immunohistochemical method was used to measure the change in irisin levels, the ELISA method to quantify blood irisin levels, and Griess' assay to determine nitric oxide (NO) levels in the serum and tissue. Myocardial ischaemia was confirmed based on the results of Masson's trichrome staining, as well as levels of troponin and creatine kinase MB.
Results:
Irisin levels in biological tissue and serum dropped statistically significantly in the ischaemic group (MI), but were restored with ILO and SIL administration. Individual SIL administration was more potently restorative than individual ILO administration or the combined administration of the two agents. NO level, on the other hand, showed the opposite tendency, reaching the highest level in the MI group, and falling with the use of pharmaceutical agents.
Conclusions:
Individual or combined administration of ILO and SIL reduced myocardial ischaemia and NO levels, and increased irisin levels. Elevated levels of irisin obtained by drug administration could possibly contribute to accelerated wound recovery by local heat production. Sildenafil was more effective than iloprost in eliminating ischaemia and may be the first choice in offsetting the effects of ischaemia in the future.
... Currently, arterial grafts, venous grafts and synthetic grafts are all used in coronary bypass surgery. Grafts are usually classified as autologous and non-autologous, and are characterized by different long-term patency rates [22]. ...
Restenosis is pathophysiological process occurring in 10-15% of patients submitted to revascularization procedures of coronary, carotid and peripheral arteries. It can be considered as an excessive healing reaction of the vascular wall submitted to arterial/venous bypass graft interposition, endarterectomy or angioplasty. The advent of bare metal stents, drug-eluting stents and of the more recent drug-eluting balloons, significantly reduced but not eliminated the incidence of restenosis, which remains a clinically relevant problem.
Biomedical research in preclinical animal models of (re)stenosis, despite its limitations, enormously contributed to the identification of processes involved in restenosis progression, going well beyond the initial dogma of a primarily proliferative disease.
Although the main molecular and cellular mechanisms underlying restenosis have been well described, new signalling molecules and cell types controlling the progress of restenosis are continuously discovered. In particular, microRNAs and vascular progenitor cells recently revealed a key role in this pathophysiological process. Also, the advanced, highly-sensitive highthroughput analyses of molecular alterations at transcriptome, proteome and metabolome level occurring in injured vessels in animal models of disease and in human specimens, are serving as a basis to identify novel potential therapeutic targets for restenosis. Molecular analyses are also contributing to the identification of reliable circulating biomarkers predictive of post-interventional restenosis in patients, that could be potentially helpful in the establishment of an early diagnosis and therapy.
This review summarizes the most recent and promising therapeutic strategies identified in experimental models of (re)stenosis and potentially translatable in patients submitted to revascularization procedures.
Purpose
Cardiopulmonary bypass (CPB) is a nonphysiological procedure in which inflammatory reactions and oxidative stress are induced, hormones and hemodynamic parameters are affected, and circulation is maintained outside the body. This study aimed to examine the effects of CPB on blood subfatin (SUB), asprossin (ASP), alamandine (ALA) and maresin-1 (MaR-1) levels.
Materials and Methods
Controls and patients who underwent open-heart surgery with CPB and whose age and body mass indices were compatible with each other were included in the study. Venous blood samples were collected from CPB patients (n =19) before anesthesia induction (T1), before CPB (T2), 5 min before cross-clamp removal (T3), 5 min after cross-clamp removal (T4), when taken to the intensive care unit (T5), postoperative 24th hour (T6) and 72nd hour (T7) postoperatively. Venous blood was collected from the healthy controls (n =19). The amounts of SUB, ASP, ALA, and MaR-1 in the blood samples were measured using an Enzyme-Linked Immunosorbent Assay (ELISA).
Results
The amounts of SUB and MaR-1 in the control group were significantly higher than those in CPB patients, while these parameters in T1-T3 blood gradually decreased in CPB patients (p<0.01). It was also reported that the amounts of ASP and ALA in the control group were significantly lower than those in CPB patients, whereas those parameters in the T1-T3 blood samples increased gradually in CPB patients, but started to decrease in T4-T7 blood samples.
Conclusion
These hormonal changes in the organism due to CPB demonstrate that “hormonal metabolic adaptation” mechanisms may be activated to eliminate the negative consequences of surgery. According to these data, SUB, MaR-1, anti-alamandine, and anti-asprosin could be used in CPB surgeries may come to the fore in the future to increase the safety of CPB surgeries.
