Potentiation of phorbol ester-induced coronary vasoconstriction in dogs following endothelium disruption

International Nuclear Information System (INIS)

Roberts, R.B.; Ku, D.D.

1986-01-01

In the present study, the effect of phorbol ester, 12-0-tetradecanoylphorbol 13-acetate (TPA), activation of protein kinase C on coronary vascular reactivity was studied in isolated dog coronary arteries. Addition of TPA (10-100 nM) produced a slow, time- and dose-dependent contraction reaching a maximum at approx 2-3 hrs and was essentially irreversible upon washing. Disruption of the endothelium(EC) greatly accelerated the development as well as increase the magnitude of TPA contraction (50-100%). Prior treatment of vessels with phentolamine (1μM), cyproheptadine (1μH) and ibuprofen (1μg/ml) did not alter the TPA contraction. Furthermore, in contrast to previously reported calcium-dependence of TPA contraction in other vessels, complete removal of extracellular calcium (Ca 0 ) or addition of 1μM nimodipine after TPA(30nM) resulted in only 32 +/- 4% and 25 +/- 3% reversal of TPA contraction, respectively. Addition of amiloride (10μM to 1mM), however, resulted in a dose-dependent reversal of TPA contraction. The results of the present study indicate that a similar activation of protein kinase C by TPA leads to potent coronary vasoconstriction, which is not completely dependent on Ca 0 . More importantly, these results further support their hypothesis that EC also functions as an inhibitory barrier to prevent circulating vasoconstrictors from exerting their deleterious constrictory effects

Pomegranate Extract Enhances Endothelium-Dependent Coronary Relaxation in Isolated Perfused Hearts from Spontaneously Hypertensive Ovariectomized Rats

Science.gov (United States)

Delgado, Nathalie T. B.; Rouver, Wender do N.; Freitas-Lima, Leandro C.; de Paula, Tiago D.-C.; Duarte, Andressa; Silva, Josiane F.; Lemos, Virgínia S.; Santos, Alexandre M. C.; Mauad, Helder; Santos, Roger L.; Moysés, Margareth R.

2017-01-01

prevented the decreasing in plasmatic nitrite. We observed a reduction in total cholesterol and LDL in the Sham-PHE group. The treatment with PHE enhances the endothelium-dependent coronary relaxation and improves cardiovascular parameters, which suggests a therapeutic role of PHE. PMID:28101057

Rat retinal vasomotion assessed by laser speckle imaging

DEFF Research Database (Denmark)

Neganova, Anastasiia Y; Postnov, Dmitry D; Sosnovtseva, Olga

2017-01-01

Vasomotion is spontaneous or induced rhythmic changes in vascular tone or vessel diameter that lead to rhythmic changes in flow. While the vascular research community debates the physiological and pathophysiological consequence of vasomotion, there is a great need for experimental techniques...... that can address the role and dynamical properties of vasomotion in vivo. We apply laser speckle imaging to study spontaneous and drug induced vasomotion in retinal network of anesthetized rats. The results reveal a wide variety of dynamical patterns. Wavelet-based analysis shows that (i) spontaneous...

Hypersensitivity to thromboxane receptor mediated cerebral vasomotion and CBF oscillations during acute NO-deficiency in rats.

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Béla Horváth

Full Text Available BACKGROUND: Low frequency (4-12 cpm spontaneous fluctuations of the cerebrovascular tone (vasomotion and oscillations of the cerebral blood flow (CBF have been reported in diseases associated with endothelial dysfunction. Since endothelium-derived nitric oxide (NO suppresses constitutively the release and vascular effects of thromboxane A(2 (TXA(2, NO-deficiency is often associated with activation of thromboxane receptors (TP. In the present study we hypothesized that in the absence of NO, overactivation of the TP-receptor mediated cerebrovascular signaling pathway contributes to the development of vasomotion and CBF oscillations. METHODOLOGY/PRINCIPAL FINDINGS: Effects of pharmacological modulation of TP-receptor activation and its downstream signaling pathway have been investigated on CBF oscillations (measured by laser-Doppler flowmetry in anesthetized rats and vasomotion (measured by isometric tension recording in isolated rat middle cerebral arteries, MCAs both under physiological conditions and after acute inhibition of NO synthesis. Administration of the TP-receptor agonist U-46619 (1 µg/kg i.v. to control animals failed to induce any changes of the systemic or cerebral circulatory parameters. Inhibition of the NO synthesis by nitro-L-arginine methyl ester (L-NAME, 100 mg/kg i.v. resulted in increased mean arterial blood pressure and a decreased CBF accompanied by appearance of CBF-oscillations with a dominant frequency of 148±2 mHz. U-46619 significantly augmented the CBF-oscillations induced by L-NAME while inhibition of endogenous TXA(2 synthesis by ozagrel (10 mg/kg i.v. attenuated it. In isolated MCAs U-46619 in a concentration of 100 nM, which induced weak and stable contraction under physiological conditions, evoked sustained vasomotion in the absence of NO, which effect could be completely reversed by inhibition of Rho-kinase by 10 µM Y-27632. CONCLUSION/SIGNIFICANCE: These results suggest that hypersensitivity of the TP

Endothelium-dependent relaxation induced by cathepsin G in porcine pulmonary arteries

Science.gov (United States)

Glusa, Erika; Adam, Christine

2001-01-01

Serine proteinases elicit profound cellular effects in various tissues mediated by activation of proteinase-activated receptors (PAR). In the present study, we investigated the vascular effects of cathepsin G, a serine proteinase that is present in the azurophil granules of leukocytes and is known to activate several cells that express PARs. In prostaglandin F2α (3 μM)-precontracted rings from porcine pulmonary arteries with intact endothelium, cathepsin G caused concentration-dependent relaxant responses (pEC50=9.64±0.12). The endothelium-dependent relaxant effect of cathepsin G could also be demonstrated in porcine coronary arteries (pEC50=9.23±0.07). In pulmonary arteries the cathepsin G-induced relaxation was inhibited after blockade of nitric oxide synthesis by L-NAME (200 μM) and was absent in endothelium-denuded vessels. Bradykinin- and cathepsin G-induced relaxant effects were associated with a 5.7 fold and 2.4 fold increase in the concentration of cyclic GMP, respectively. Compared with thrombin and trypsin, which also produced an endothelium-dependent relaxation in pulmonary arteries, cathepsin G was 2.5 and four times more potent, respectively. Cathepsin G caused only small homologous desensitization. In cathepsin G-challenged vessels, thrombin was still able to elicit a relaxant effect. The effects of cathepsin G were blocked by soybean trypsin inhibitor (IC50=0.043 μg ml−1), suggesting that proteolytic activity is essential for induction of relaxation. Recombinant acetyl-eglin C proved to be a potent inhibitor (IC50=0.14 μg ml−1) of the cathepsin G effect, whereas neither indomethacin (3 μM) nor the thrombin inhibitor hirudin (5 ATU ml−1) elicited any inhibitory activity. Due to their polyanionic structure defibrotide (IC50=0.11 μg ml−1), heparin (IC50=0.48 μg ml−1) and suramin (IC50=1.85 μg ml−1) diminished significantly the relaxation in response to the basic protein cathepsin G. In conclusion, like

Enhanced vasomotion of cerebral arterioles in spontaneously hypertensive rats

Science.gov (United States)

Lefer, D. J.; Lynch, C. D.; Lapinski, K. C.; Hutchins, P. M.

1990-01-01

Intrinsic rhythmic changes in the diameter of pial cerebral arterioles (30-70 microns) in anesthetized normotensive and hypertensive rats were assessed in vivo to determine if any significant differences exist between the two strains. All diameter measurements were analyzed using a traditional graphic analysis technique and a new frequency spectrum analysis technique known as the Prony Spectral Line Estimator. Graphic analysis of the data revealed that spontaneously hypertensive rats (SHR) possess a significantly greater fundamental frequency (5.57 +/- 0.28 cycles/min) of vasomotion compared to the control Wistar-Kyoto normotensive rats (WKY) (1.95 +/- 0.37 cycles/min). Furthermore, the SHR cerebral arterioles exhibited a significantly greater amplitude of vasomotion (10.07 +/- 0.70 microns) when compared to the WKY cerebral arterioles of the same diameter (8.10 +/- 0.70 microns). Diameter measurements processed with the Prony technique revealed that the fundamental frequency of vasomotion in SHR cerebral arterioles (6.14 +/- 0.39 cycles/min) was also significantly greater than that of the WKY cerebral arterioles (2.99 +/- 0.42 cycles/min). The mean amplitudes of vasomotion in the SHR and WKY strains obtained by the Prony analysis were found not to be statistically significant in contrast to the graphic analysis of the vasomotion amplitude of the arterioles. In addition, the Prony system was able to consistently uncover a very low frequency of vasomotion in both strains of rats that was typically less than 1 cycle/min and was not significantly different between the two strains. The amplitude of this slow frequency was also not significantly different between the two strains. The amplitude of the slow frequency of vasomotion (less than 1 cycle/min) was not different from the amplitude of the higher frequency (2-6 cycles/min) vasomotion by Prony or graphic analysis. These data suggest that a fundamental intrinsic defect exists in the spontaneously hypertensive rat

Amiodarona causa vasodilatação dependente do endotélio em artérias coronárias caninas Amiodarone causes endothelium-dependent vasodilation in canine coronary arteries

Directory of Open Access Journals (Sweden)

Alfredo José Rodrigues

2005-03-01

polysorbate 80, amiodarone dissolved in water, amiodarone dissolved in polysorbate 80, and a commercial presentation of amiodarone (Cordarone. The experiments were conducted in the presence of the following enzymatic blockers: only indomethacin, Nw-nitro-L-arginine associated with indomethacin, and only Nw-nitro-L-arginine. RESULTS: Polysorbate 80 caused a small degree of nonendothelium-dependent relaxation. Cordarone, amiodarone dissolved in water, and amiodarone dissolved in polysorbate 80 caused endothelium-dependent relaxation, which was greater for amiodarone dissolved in polysorbate and for Cordarone. Only the association of indomethacin and Nw-nitro-L-arginine could eliminate the endothelium-dependent relaxation caused by amiodarone dissolved in polysorbate 80. CONCLUSION: The results obtained indicate that vasodilation promoted by amiodarone in canine coronary arteries is mainly caused by stimulation of the release of nitric oxide and cyclooxygenase-dependent relaxing endothelial factors.

Novel approaches to improving endothelium-dependent nitric oxide-mediated vasodilatation

DEFF Research Database (Denmark)

Simonsen, Ulf; Rodriguez-Rodriguez, Rosalia; Dalsgaard, Thomas

2009-01-01

Endothelial dysfunction, which is defined by decreased endothelium-dependent vasodilatation, is associated with an increased number of cardiovascular events. Nitric oxide (NO) bioavailability is reduced by altered endothelial signal transduction or increased formation of radical oxygen species...... reacting with NO. Endothelial dysfunction is therapeutically reversible and physical exercise, calcium channel blockers, angiotensin converting enzyme inhibitors, and angiotensin receptor antagonists improve flow-evoked endothelium-dependent vasodilation in patients with hypertension and diabetes. We have...... the endothelial signal transduction pathways involved in vasorelaxation and NO release induced by an olive oil component, oleanolic acid, and (3) investigated the role of calcium-activated K channels in the release of NO induced by receptor activation. Tempol increases endothelium-dependent vasodilatation...

Vildagliptin Improves Endothelium-Dependent Vasodilatation in Type 2 Diabetes

Science.gov (United States)

van Poppel, Pleun C.M.; Netea, Mihai G.; Smits, Paul; Tack, Cees J.

2011-01-01

OBJECTIVE To investigate whether the dipeptidyl peptidase-4 inhibitor vildagliptin improves endothelium-dependent vasodilatation in patients with type 2 diabetes. RESEARCH DESIGN AND METHODS Sixteen subjects with type 2 diabetes (age 59.8 ± 6.8 years, BMI 29.1 ± 4.8 kg/m2, HbA1c 6.97 ± 0.61) on oral blood glucose–lowering treatment were included. Participants received vildagliptin 50 mg b.i.d. or acarbose 100 mg t.i.d. for four consecutive weeks in a randomized, double-blind, cross-over design. At the end of each treatment period, we measured forearm vasodilator responses to intra-arterially administered acetylcholine (endothelium-dependent vasodilator) and sodium nitroprusside (endothelium-independent vasodilator). RESULTS Infusion of acetylcholine induced a dose-dependent increase in forearm blood flow in the experimental arm, which was higher during vildagliptin (3.1 ± 0.7, 7.9 ± 1.1, and 12.6 ± 1.4 mL ⋅ dL−1 ⋅ min−1 in response to three increasing dosages of acetylcholine) than during acarbose (2.0 ± 0.7, 5.0 ± 1.2, and 11.7 ± 1.6 mL ⋅ dL−1 ⋅ min−1, respectively; P = 0.01 by two-way ANOVA). Treatment with vildagliptin did not significantly change the vascular responses to sodium nitroprusside. CONCLUSIONS Four weeks’ treatment with vildagliptin improves endothelium-dependent vasodilatation in subjects with type 2 diabetes. This observation might have favorable cardiovascular implications. PMID:21788633

Endothelium-independent and endothelium-dependent ...

African Journals Online (AJOL)

This endothelium-independent relaxant effect was also sensitive to combination of 1H-[1,2,4]-oxadiazole-[4,3-á]-quinoxalin- 1-one (ODQ, 10 ìM, soluble guanylyl cyclase inhibitor) and N-[2-(p-Bromocinnamylamino)ethyl]-5-isoquinoline sulfonamide dihydrochloride (H89, 100 nM, Protein Kinase A inhibitor). Taken together ...

Maternal nutrient restriction during pregnancy impairs an endothelium-derived hyperpolarizing factor-like pathway in sheep fetal coronary arteries.

Science.gov (United States)

Shukla, Praveen; Ghatta, Srinivas; Dubey, Nidhi; Lemley, Caleb O; Johnson, Mary Lynn; Modgil, Amit; Vonnahme, Kimberly; Caton, Joel S; Reynolds, Lawrence P; Sun, Chengwen; O'Rourke, Stephen T

2014-07-15

The mechanisms underlying developmental programming are poorly understood but may be associated with adaptations by the fetus in response to changes in the maternal environment during pregnancy. We hypothesized that maternal nutrient restriction during pregnancy alters vasodilator responses in fetal coronary arteries. Pregnant ewes were fed a control [100% U.S. National Research Council (NRC)] or nutrient-restricted (60% NRC) diet from days 50 to 130 of gestation (term = 145 days); fetal tissues were collected at day 130. In coronary arteries isolated from control fetal lambs, relaxation to bradykinin was unaffected by nitro-l-arginine (NLA). Iberiotoxin or contraction with KCl abolished the NLA-resistant response to bradykinin. In fetal coronary arteries from nutrient-restricted ewes, relaxation to bradykinin was fully suppressed by NLA. Large-conductance, calcium-activated potassium channel (BKCa) currents did not differ in coronary smooth muscle cells from control and nutrient-restricted animals. The BKCa openers, BMS 191011 and NS1619, and 14,15-epoxyeicosatrienoic acid [a putative endothelium-derived hyperpolarizing factor (EDHF)] each caused fetal coronary artery relaxation and BKCa current activation that was unaffected by maternal nutrient restriction. Expression of BKCa-channel subunits did not differ in fetal coronary arteries from control or undernourished ewes. The results indicate that maternal undernutrition during pregnancy results in loss of the EDHF-like pathway in fetal coronary arteries in response to bradykinin, an effect that cannot be explained by a decreased number or activity of BKCa channels or by decreased sensitivity to mediators that activate BKCa channels in vascular smooth muscle cells. Under these conditions, bradykinin-induced relaxation is completely dependent on nitric oxide, which may represent an adaptive response to compensate for the absence of the EDHF-like pathway. Copyright © 2014 the American Physiological Society.

The relationship of vascular endothelial marker and endothelium-dependent vasodilatation in patients with essential hypertension

International Nuclear Information System (INIS)

Chen Yongjian; Zhou Yonglie; Hu Qingfeng; Qiu Liannv

2009-01-01

Objective: To explore the relationship of vascular endothelial marker and endothelium-dependent vasodilatation in patients with essential hypertension (EH). Methods: Plasma endothlium (ET-1) (with RIA) and von Willber factor (vWF)(with ELISA) levels were measured both before and after 12 wks' treatment in 56 patients with essential hypertension and 32 controls. The brachial artery endothelium-dependent vasodilatation function was examined with high resolving color doppler ultra-sonography. The 56 patients with EH were of two groups A. high and very high risk, n=26 B. low and moderate risk, n=30. Results: Plasma levels of ET-1, vWF in patients with EH as a whole were significantly higher than those in controls group [(53.3±16.2)pg/ml vs(42.5±8.5)pg/ml, (158.2±28.6)% vs(130.6±35.2)%], endothelium-dependent vasodilatation function wasmuch reduced in patients with EH(7.5±4.2)% vs controls(12.3±4.3)%. Among the patients, values in Group A were significantly different from those in Group B. After treatment for 12 weeks, plasma ET-1 and vWF and endothelium-dependent vasodilatation function were significantly improved. There was negative correlation between vascular endothelial marker levels and endothelium-dependent vasodilatation function. Conclusion: The endothelium-dependent vasodilatation function was impaired and plasma ET-1 and vWF levels were increased in patients with EH, the endothelial dysfunction was closely associated with the risk level of EH. Vascular endothelial markers were useful indicators for evaluation of the endothelium-dependent vasodilatation function. (authors)

Obesity and risk of vascular disease: importance of endothelium-dependent vasoconstriction.

Science.gov (United States)

Barton, Matthias; Baretella, Oliver; Meyer, Matthias R

2012-02-01

Obesity has become a serious global health issue affecting both adults and children. Recent devolopments in world demographics and declining health status of the world's population indicate that the prevalence of obesity will continue to increase in the next decades. As a disease, obesity has deleterious effects on metabolic homeostasis, and affects numerous organ systems including heart, kidney and the vascular system. Thus, obesity is now regarded as an independent risk factor for atherosclerosis-related diseases such as coronary artery disease, myocardial infarction and stroke. In the arterial system, endothelial cells are both the source and target of factors contributing to atherosclerosis. Endothelial vasoactive factors regulate vascular homeostasis under physiological conditions and maintain basal vascular tone. Obesity results in an imbalance between endothelium-derived vasoactive factors favouring vasoconstriction, cell growth and inflammatory activation. Abnormal regulation of these factors due to endothelial cell dysfunction is both a consequence and a cause of vascular disease processes. Finally, because of the similarities of the vascular pathomechanisms activated, obesity can be considered to cause accelerated, 'premature' vascular aging. Here, we will review some of the pathomechanisms involved in obesity-related activation of endothelium-dependent vasoconstriction, the clinical relevance of obesity-associated vascular risk, and therapeutic interventions using 'endothelial therapy' aiming at maintaining or restoring vascular endothelial health. This article is part of a themed section on Fat and Vascular Responsiveness. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2012.165.issue-3. © 2011 The Authors. British Journal of Pharmacology © 2011 The British Pharmacological Society.

Resveratrol Protects and Restores Endothelium-Dependent Relaxation in Hypercholesterolemic Rabbit Corpus Cavernosum.

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Murat, Nergiz; Korhan, Peyda; Kizer, Onur; Evcim, Sinem; Kefi, Aykut; Demir, Ömer; Gidener, Sedef; Atabey, Neşe; Esen, Ahmet Adil

2016-01-01

Oxidative stress dependent-decrease in nitric oxide (NO) bioavailability plays an integral role in hypercholesterolemia-induced erectile dysfunction (ED). Resveratrol has been demonstrated to exert beneficial effects against oxidative stress and improve NO bioavailability. The protective and restorative potentials of resveratrol on endothelium-dependent relaxations were evaluated in hypercholesterolemic rabbit corpus cavernosum (CC). Hypercholesterolemia was induced by administering 2% cholesterol diet (CD) (w/w) to the rabbits for 6 weeks. Two different protocols were applied to test the effects of resveratrol on hypercholesterolemia-induced ED. In Protocol-1 (P1), resveratrol was administrated to the rabbits simultaneously with CD in order to evaluate the protective effect, and for Protocol-2 (P2), resveratrol was administrated for 6 weeks after termination of CD in order to evaluate the restorative effect. Endothelium-dependent relaxations of CC were evaluated by using organ bath studies. In order to elucidate the possible molecular mechanisms, we measured endothelial NO synthase (eNOS) and phosphovasodilator-stimulated phosphoprotein (VASP) expressions and activations, NADPH oxidase, superoxide dismutase (SOD), and catalase (CAT) and glutathione peroxidase (GPx) activity in cavernosal tissues obtained at the end of the study. Resveratrol showed an improvement in the endothelium-dependent relaxation responses in vitro. We demonstrated significantly increased activatory-phosphorylation (p[S1177]-eNOS) and activated phosphovasodilator-stimulated phosphoprotein (phospho-VASP) levels, but reduced phosphorylation (p[T495]-eNOS) of eNOS and NADPH oxidase activity in the resveratrol-administered HC animals compared with hypercholesterolemic control rabbits in the P1. In the P2, resveratrol exhibited an improvement in endothelium-dependent relaxation responses and more pronounced effects on eNOS activation. Resveratrol administration, either simultaneously with HC diet

Vildagliptin improves endothelium-dependent vasodilatation in type 2 diabetes

NARCIS (Netherlands)

van Poppel, P.C.; Netea, M.G.; Smits, P.; Tack, C.J.J.

2011-01-01

OBJECTIVE: To investigate whether the dipeptidyl peptidase-4 inhibitor vildagliptin improves endothelium-dependent vasodilatation in patients with type 2 diabetes. RESEARCH DESIGN AND METHODS: Sixteen subjects with type 2 diabetes (age 59.8 +/- 6.8 years, BMI 29.1 +/- 4.8 kg/m(2), HbA(1c) 6.97 +/-

Endothelium-dependent vasodilatation, plasma markers of endothelial function, and adrenergic vasoconstrictor responses in type 1 diabetes under near-normoglycemic conditions

NARCIS (Netherlands)

Huvers, F C; De Leeuw, P W; Houben, A J; De Haan, C H; Hamulyak, K; Schouten, H; Wolffenbuttel, B H; Schaper, N C

It is unknown whether and to what extent changes in various endothelial functions and adrenergic responsiveness are related to the development of microvascular complications in type 1 diabetes. Therefore, endothelium-dependent and endothelium-independent vasodilatation, endothelium-dependent

Maternal smoking and impaired endothelium-dependent nitric oxide-mediated relaxation of uterine small arteries in vitro

DEFF Research Database (Denmark)

Andersen, Malene R; Uldbjerg, Niels; Stender, Steen

2011-01-01

This study aimed to investigate the endothelium-dependent relaxation of uterine small arteries from pregnant nonsmokers, smokers, and ex-smokers who stopped smoking early in pregnancy.......This study aimed to investigate the endothelium-dependent relaxation of uterine small arteries from pregnant nonsmokers, smokers, and ex-smokers who stopped smoking early in pregnancy....

Arbutus unedo induces endothelium-dependent relaxation of the isolated rat aorta.

Science.gov (United States)

Ziyyat, Abderrahim; Mekhfi, Hassane; Bnouham, Mohamed; Tahri, Abdelhafid; Legssyer, Abdelkhaleq; Hoerter, Jacqueline; Fischmeister, Rodolphe

2002-09-01

Arbutus unedo L. (Ericaceae) is used in oriental Morocco to treat arterial hypertension. We studied its vasodilator effect and mechanisms of action in vitro. The root aqueous extract of Arbutus (0.25 mg/mL) produced a relaxation of noradrenaline-precontracted ring preparations of rat aorta with intact endothelium. Relaxation by Arbutus did not occur in specimens without endothelium and was inhibited by pretreatment with 100 microM N(G)-methyl-L-arginine (L-NMA), 10 microM methylene blue or 50 microM 1H-[1,2,4] oxadiazolo [4,3-a] quinoxaline-1-one (ODQ) but not by 10 microM atropine. These results suggest that Arbutus produces an endothelium-dependent relaxation of the isolated rat aorta which may be mediated mainly by a stimulation of the endothelial nitric oxide synthase by mechanisms other than activation of muscarinic receptors. Copyright 2002 John Wiley & Sons, Ltd.

Gou-teng (from Uncaria rhynchophylla Miquel)-induced endothelium-dependent and -independent relaxations in the isolated rat aorta.

Science.gov (United States)

Kuramochi, T; Chu, J; Suga, T

1994-01-01

Gou-teng is a drug used for treatment of hypertension in Chinese medicine. Its antihypertensive action has been previously confirmed in the spontaneously hypertensive rat (SHR). Here, its vasorelaxing effect and the mechanisms of actions were studied in vitro. Gou-teng extract (GTE) relaxed the norepinephrine (NE)-precontracted aortic ring preparations isolated from Wistar Kyoto rats (WKY) with and without intact endothelium; the latter was significantly less sensitive than the former. The GTE-induced endothelium-dependent relaxation was significantly inhibited by NG-monomethyl-L-arginine (NMMA) in a dose-dependent manner while indomethacin did not affect the relaxation. Atropine inhibited the acetylcholine (ACh)-induced endothelium-dependent relaxation but did not the GTE-induced one. Furthermore, once GTE was applied, the following NE-induced contraction was significantly reduced even after repeated washout. NMMA effectively reduced and rather reversed this residual effect of GTE. From these results, it is concluded that GTE relaxes the NE-precontracted rat aorta through endothelium-dependent and, to lesser extent, -independent mechanisms. The endothelium-dependent component would be mediated by EDRF/NO pathway in which the muscarinic cholinoceptors were not involved. Thus, GTE appears to be a potent and long-lasting vasodilator mainly through EDRF/NO release.

[Absorbable coronary stents. New promising technology].

Science.gov (United States)

Erbel, Raimund; Böse, Dirk; Haude, Michael; Kordish, Igor; Churzidze, Sofia; Malyar, Nasser; Konorza, Thomas; Sack, Stefan

2007-06-01

revascularization rate of 23.8% which was below the 30% cut point of the study protocol. No myocardial Q wave infarction or death were reported. The primary endpoint was reached. During the follow-up period, vasomotion was tested in some of the patients. The proof of principle was confirmed: restoration of vasomotion during acetylcholine testing. The development of the absorbable magnesium stent, which was pushed forward by B. Heublein, Hanover, Germany, has been successful and opens new possibilities for treatment of coronary arteries. Permanent foreign-body implantation is avoided allowing further revascularization procedures in the future, bypass grafting, and restoration of vasomotion. Even prophylactic stenting in nonsignificant stenosis, like vulnerable lesions, may become a regular procedure. Noninvasive coronary imaging by CT and MRI is now possible. Stenting of children and in peripheral arteries may become a standard procedure. Currently, the degradation process of the magnesium stent has to be prolonged, and the neointima proliferation rate has to be reduced so that the DREAM (Drug-Eluting Absorbable Magnesium Stent) concept of Ron Waksman, Washington, DC, USA, can be realized.

Mechanisms of cellular synchronization in the vascular wall. Mechanisms of vasomotion.

Science.gov (United States)

Matchkov, Vladimir V

2010-10-01

manner. I have shown that inhibition of the ouabain-sensitive Na+, K+-ATPase inhibits calcium efflux by the Na+/Ca2+-exchanger and this leads to the local elevation of intracellular calcium and inhibition of intercellular communications. This explains the inhibitory action of ouabain on vasomotion. I have also found that the ATP-dependent K+ channel is an important player in this functional unit and this interaction is reciprocal, since K+ channel supplies Na+, K+-ATPase with K+ ions while the ATP-dependent K+ channel current also regulates the Na+, K+-ATPase. This dissertation is based on nine scientific publications where I have suggested the model for generation of vasomotion and characterized the essential elements of this model.

In vivo evidence for an endothelium-dependent mechanism in radiation-induced normal tissue injury

Science.gov (United States)

Rannou, Emilie; François, Agnès; Toullec, Aurore; Guipaud, Olivier; Buard, Valérie; Tarlet, Georges; Mintet, Elodie; Jaillet, Cyprien; Iruela-Arispe, Maria Luisa; Benderitter, Marc; Sabourin, Jean-Christophe; Milliat, Fabien

2015-01-01

The pathophysiological mechanism involved in side effects of radiation therapy, and especially the role of the endothelium remains unclear. Previous results showed that plasminogen activator inhibitor-type 1 (PAI-1) contributes to radiation-induced intestinal injury and suggested that this role could be driven by an endothelium-dependent mechanism. We investigated whether endothelial-specific PAI-1 deletion could affect radiation-induced intestinal injury. We created a mouse model with a specific deletion of PAI-1 in the endothelium (PAI-1KOendo) by a Cre-LoxP system. In a model of radiation enteropathy, survival and intestinal radiation injury were followed as well as intestinal gene transcriptional profile and inflammatory cells intestinal infiltration. Irradiated PAI-1KOendo mice exhibited increased survival, reduced acute enteritis severity and attenuated late fibrosis compared with irradiated PAI-1flx/flx mice. Double E-cadherin/TUNEL labeling confirmed a reduced epithelial cell apoptosis in irradiated PAI-1KOendo. High-throughput gene expression combined with bioinformatic analyses revealed a putative involvement of macrophages. We observed a decrease in CD68+cells in irradiated intestinal tissues from PAI-1KOendo mice as well as modifications associated with M1/M2 polarization. This work shows that PAI-1 plays a role in radiation-induced intestinal injury by an endothelium-dependent mechanism and demonstrates in vivo that the endothelium is directly involved in the progression of radiation-induced enteritis. PMID:26510580

Tibolone and its metabolites acutely relax rabbit coronary arteries in vitro

DEFF Research Database (Denmark)

Lund, Claus Otto; Nilas, Lisbeth; Pedersen, Susan Helene

2004-01-01

under curve (AUC). RESULTS: Tibolone and its metabolites induced a concentration-dependent vasodilatation comparable to that of 17 beta-estradiol with the rank of potency: 3 beta-OH-tibolone approximately = to tibolone>3 alpha-OH-tibolone>Delta 4-isomer (ANOVA). l-NAME partly inhibited the relaxation.......05, ANOVA). CONCLUSIONS: Our data indicate that the acute relaxation induced by tibolone and its metabolites in coronary arteries in vitro are probably mediated by endothelium independent inhibition of calcium channels but may also involve an endothelium-dependent mechanism via nitric oxide. The effect...

Effect of the Menstrual Cycle on Maximum Oxygen Consumption and Endothelium-Dependent Vasodilation

National Research Council Canada - National Science Library

Andrews, Thomas

1997-01-01

.... We studied endothelium-dependent vasodilation of the brachial artery during three phases of the menstrual cycle in 20 eumenorrheic subjects to determine the effect of endogenous estradiol and progesterone...

Upregulation of SK3 and IK1 channels contributes to the enhanced endothelial calcium signaling and the preserved coronary relaxation in obese Zucker rats.

Directory of Open Access Journals (Sweden)

Belén Climent

Full Text Available Endothelial small- and intermediate-conductance KCa channels, SK3 and IK1, are key mediators in the endothelium-derived hyperpolarization and relaxation of vascular smooth muscle and also in the modulation of endothelial Ca2+ signaling and nitric oxide (NO release. Obesity is associated with endothelial dysfunction and impaired relaxation, although how obesity influences endothelial SK3/IK1 function is unclear. Therefore we assessed whether the role of these channels in the coronary circulation is altered in obese animals.In coronary arteries mounted in microvascular myographs, selective blockade of SK3/IK1 channels unmasked an increased contribution of these channels to the ACh- and to the exogenous NO- induced relaxations in arteries of Obese Zucker Rats (OZR compared to Lean Zucker Rats (LZR. Relaxant responses induced by the SK3/IK1 channel activator NS309 were enhanced in OZR and NO- endothelium-dependent in LZR, whereas an additional endothelium-independent relaxant component was found in OZR. Fura2-AM fluorescence revealed a larger ACh-induced intracellular Ca2+ mobilization in the endothelium of coronary arteries from OZR, which was inhibited by blockade of SK3/IK1 channels in both LZR and OZR. Western blot analysis showed an increased expression of SK3/IK1 channels in coronary arteries of OZR and immunohistochemistry suggested that it takes place predominantly in the endothelial layer.Obesity may induce activation of adaptive vascular mechanisms to preserve the dilator function in coronary arteries. Increased function and expression of SK3/IK1 channels by influencing endothelial Ca2+ dynamics might contribute to the unaltered endothelium-dependent coronary relaxation in the early stages of obesity.

Inward rectifier potassium (Kir2.1) channels as end-stage boosters of endothelium-dependent vasodilators.

Science.gov (United States)

Sonkusare, Swapnil K; Dalsgaard, Thomas; Bonev, Adrian D; Nelson, Mark T

2016-06-15

Increase in endothelial cell (EC) calcium activates calcium-sensitive intermediate and small conductance potassium (IK and SK) channels, thereby causing hyperpolarization and endothelium-dependent vasodilatation. Endothelial cells express inward rectifier potassium (Kir) channels, but their role in endothelium-dependent vasodilatation is not clear. In the mesenteric arteries, only ECs, but not smooth muscle cells, displayed Kir currents that were predominantly mediated by the Kir2.1 isoform. Endothelium-dependent vasodilatations in response to muscarinic receptor, TRPV4 (transient receptor potential vanilloid 4) channel and IK/SK channel agonists were highly attenuated by Kir channel inhibitors and by Kir2.1 channel knockdown. These results point to EC Kir channels as amplifiers of vasodilatation in response to increases in EC calcium and IK/SK channel activation and suggest that EC Kir channels could be targeted to treat endothelial dysfunction, which is a hallmark of vascular disorders. Endothelium-dependent vasodilators, such as acetylcholine, increase intracellular Ca(2+) through activation of transient receptor potential vanilloid 4 (TRPV4) channels in the plasma membrane and inositol trisphosphate receptors in the endoplasmic reticulum, leading to stimulation of Ca(2+) -sensitive intermediate and small conductance K(+) (IK and SK, respectively) channels. Although strong inward rectifier K(+) (Kir) channels have been reported in the native endothelial cells (ECs) their role in EC-dependent vasodilatation is not clear. Here, we test the idea that Kir channels boost the EC-dependent vasodilatation of resistance-sized arteries. We show that ECs, but not smooth muscle cells, of small mesenteric arteries have Kir currents, which are substantially reduced in EC-specific Kir2.1 knockdown (EC-Kir2.1(-/-) ) mice. Elevation of extracellular K(+) to 14 mm caused vasodilatation of pressurized arteries, which was prevented by endothelial denudation and Kir channel

Immuno-Spin Trapping-Based Detection of Oxidative Modifications in Cardiomyocytes and Coronary Endothelium in the Progression of Heart Failure in Tgαq*44 Mice

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Bartosz Proniewski

2018-05-01

Full Text Available Recent studies suggest both beneficial and detrimental role of increased reactive oxygen species and oxidative stress in heart failure (HF. However, it is not clear at which stage oxidative stress and oxidative modifications occur in the endothelium in relation to cardiomyocytes in non-ischemic HF. Furthermore, most methods used to date to study oxidative stress are either non-specific or require tissue homogenization. In this study, we used immuno-spin trapping (IST technique with fluorescent microscopy-based detection of DMPO nitrone adducts to localize and quantify oxidative modifications of the hearts from Tgαq*44 mice; a murine model of HF driven by cardiomyocyte-specific overexpression of Gαq* protein. Tgαq*44 mice and age-matched FVB controls at early, transition, and late stages of HF progression were injected with DMPO in vivo and analyzed ex vivo for DMPO nitrone adducts signals. Progressive oxidative modifications in cardiomyocytes, as evidenced by the elevation of DMPO nitrone adducts, were detected in hearts from 10- to 16-month-old, but not in 8-month-old Tgαq*44 mice, as compared with age-matched FVB mice. The DMPO nitrone adducts were detected in left and right ventricle, septum, and papillary muscle. Surprisingly, significant elevation of DMPO nitrone adducts was also present in the coronary endothelium both in large arteries and in microcirculation simultaneously, as in cardiomyocytes, starting from 10-month-old Tgαq*44 mice. On the other hand, superoxide production in heart homogenates was elevated already in 6-month-old Tgαq*44 mice and progressively increased to high levels in 14-month-old Tgαq*44 mice, while the enzymatic activity of catalase, glutathione reductase, and glutathione peroxidase was all elevated as early as in 4-month-old Tgαq*44 mice and stayed at a similar level in 14-month-old Tgαq*44. In summary, this study demonstrates that IST represents a unique method that allows to quantify oxidative

The effect of bioresorbable vascular scaffold implantation on distal coronary endothelial function in dyslipidemic swine with and without diabetes.

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van den Heuvel, Mieke; Sorop, Oana; van Ditzhuijzen, Nienke S; de Vries, René; van Duin, Richard W B; Peters, Ilona; van Loon, Janine E; de Maat, Moniek P; van Beusekom, Heleen M; van der Giessen, Wim J; Jan Danser, A H; Duncker, Dirk J

2018-02-01

We studied the effect of bioresorbable vascular scaffold (BVS) implantation on distal coronary endothelial function, in swine on a high fat diet without (HFD) or with diabetes (DM+HFD). Five DM+HFD and five HFD swine underwent BVS implantation on top of coronary plaques, and were studied six months later. Conduit artery segments >5mm proximal and distal to the scaffold and corresponding segments of non-scaffolded coronary arteries, and segments of small arteries within the flow-territory of scaffolded and non-scaffolded arteries were harvested for in vitro vasoreactivity studies. Conduit segments proximal and distal of the BVS edges showed reduced endothelium-dependent vasodilation as compared to control vessels (p≤0.01), with distal segments being most prominently affected(p≤0.01). Endothelial dysfunction was only observed in DM±HFD swine and was principally due to a loss of NO. Endothelium-independent vasodilation and vasoconstriction were unaffected. Surprisingly, segments from the microcirculation distal to the BVS showed enhanced endothelium-dependent vasodilation (pswine, and did not appear to be either NO- or EDHF-mediated. Six months of BVS implantation in DM+HFD swine causes NO-mediated endothelial dysfunction in nearby coronary segments, which is accompanied by a, possibly compensatory, increase in endothelial function of the distal microcirculation. Endothelial dysfunction extending into coronary conduit segments beyond the implantation-site, is in agreement with recent reports expressing concern for late scaffold thrombosis and of early BVS failure in diabetic patients. Copyright © 2017. Published by Elsevier B.V.

Recruitment of quiet cells at the onset of vasomotion in mesenteric arteries

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Brings Jacobsen, Jens Christian; Aalkjær, Christian; Matchkov, Vladimir

2008-01-01

quiet. At the onset of vasomotion however, all cells, including those that were previously quiet, are forced into synchronized oscillation. We hypothesize that this entrainment of previously quiet cells is caused by the driving force from a collective cyclic variation in membrane potential.   Methods...

Endothelium-Dependent Relaxation Effect of Apocynum venetum Leaf Extract via Src/PI3K/Akt Signalling Pathway

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Yeh Siang Lau

2015-06-01

Full Text Available Botanical herbs are consumed globally not only as an essential diet but also as medicines or as functional/recreational food supplements. The extract of the Apocynum venetum leaves (AVLE, also known as Luobuma, exerts its antihypertensive effect via dilating the blood vessels in an endothelium- and concentration-dependent manner with optimal effect seen at as low as 10 µg/mL. A commercial Luoboma “antihypertensive tea” is available commercially in the western province of China. The present study seeks to investigate the underlying cellular mechanisms of the nitric oxide (NO-releasing property of AVLE in rat aortas and human umbilical vein endothelial cells (HUVECs. Endothelium-dependent relaxation induced by AVLE was assessed in organ chambers in the presence or absence of polyethyleneglycol catalase (PP2, 20 µM; inhibitor of Src kinase, wortmannin (30 nM and LY294002 (20 µM; PI3 (phosphatidylinositol3-Kinase inhibitor, NG-nitro-l-arginine (L-NAME, 100 µM; endothelial NO synthase inhibitor (eNOS and ODQ (1 µM; soluble guanylyl cyclase inhibitor. Total nitrite and nitrate (NOx level and protein expression of p-Akt and p-eNOS were measured. AVLE-induced endothelium-dependent relaxation was reduced by PP2, wortmannin and LY294002 and abolished by L-NAME and ODQ. AVLE significantly increased total NOx level in rat aortas and in HUVECs compared to control. It also instigated phosphorylation of Akt and eNOS in cultured HUVECs in a concentration-dependent manner and this was markedly suppressed by PP2, wortmannin and LY294002. AVLE also inhibited superoxide generated from both NADPH oxidase and xanthine/xanthine oxidase system. Taken together, AVLE causes endothelium-dependent NO mediated relaxations of rat aortas through Src/PI3K/Akt dependent NO signalling pathway and possesses superoxide scavenging activity.

Sympathetic mediated vasomotion and skin capillary permeability in diabetic patients with peripheral neuropathy

NARCIS (Netherlands)

Lefrandt, JD; Hoeven, JH; Roon, AM; Smit, AJ; Hoogenberg, K

Aims/hypothesis. A loss of sympathetic function could lead to changes in capillary fluid filtration in diabetic patients. We investigated whether a decreased sympathetically mediated vasomotion in the skin in diabetic patients with peripheral neuropathy is associated with an abnormal capillary

Effect of lithium on endothelium-dependent and neurogenic relaxation of rat corpus cavernosum: role of nitric oxide pathway.

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Sadeghipour, Hamed; Ghasemi, Mehdi; Ebrahimi, Farzad; Dehpour, Ahmad Reza

2007-02-01

Some studies have reported erectile dysfunction in patients receiving lithium through a mechanism that has not yet been defined. The aim of the present study was to verify the effect of acute lithium administration on the nonadrenergic noncholinergic (NANC)- and endothelium-mediated relaxation of rat isolated corpus cavernosum. The isolated rat corporeal strips were precontracted with phenylephrine hydrochloride (7.5 microM) and electrical field stimulation (EFS) was applied at different frequencies (2, 5, 10, and 15 Hz) to obtain NANC-mediated relaxation or relaxed by adding cumulative doses of acetylcholine (10nM-1mM) to obtain endothelium-dependent relaxation in the presence or absence of lithium (0.3, 0.5, 1, and 5mM). Also, effects of combining lithium (0.3mM) with 30 nM and 0.1 nM L-NAME (an NO synthase inhibitor) on NANC- and acetylcholine-mediated relaxation was investigated, respectively. Moreover, effects of combining lithium (1mM) with 0.1mM and 10 microM L-arginine (a precursor of NO) on NANC- and endothelium-mediated relaxation was assessed, respectively. Also, the effect of lithium (1mM) on relaxation to sodium nitroprusside (SNP; 1nM-1mM), an NO donor, was investigated. The NANC-mediated relaxation was significantly (Pacetylcholine in a concentration-dependent manner. Combination of lithium (0.3mM) with 30 and 0.1 nM L-NAME, which separately had a minimum effect on NANC- and endothelium-mediated relaxation, significantly (Pacetylcholine and EFS, it improved the inhibition by lithium (1mM) of relaxant responses to acetylcholine and EFS, respectively. Also, SNP produced similar concentration-dependent relaxations from both groups. Our experiments indicated that lithium likely by interfering with NO pathway in both endothelium and nitrergic nerve can result in impairment of both the endothelium- and NANC-mediated relaxation of rat corpus cavernosum.

The ent-15α-Acetoxykaur-16-en-19-oic Acid Relaxes Rat Artery Mesenteric Superior via Endothelium-Dependent and Endothelium-Independent Mechanisms

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Êurica Adélia Nogueira Ribeiro

2012-01-01

Full Text Available The objective of the study was to investigate the mechanism of the relaxant activity of the ent-15α-acetoxykaur-16-en-19-oic acid (KA-acetoxy. In rat mesenteric artery rings, KA-acetoxy induced a concentration-dependent relaxation in vessels precontracted with phenylephrine. In the absence of endothelium, the vasorelaxation was significantly shifted to the right without reduction of the maximum effect. Endothelium-dependent relaxation was significantly attenuated by pretreatment with L-NAME, an inhibitor of the NO-synthase (NOS, indomethacin, an inhibitor of the cyclooxygenase, L-NAME + indomethacin, atropine, a nonselective antagonist of the muscarinic receptors, ODQ, selective inhibitor of the guanylyl cyclase enzyme, or hydroxocobalamin, a nitric oxide scavenger. The relaxation was completely reversed in the presence of L-NAME + 1 mM L-arginine or L-arginine, an NO precursor. Diterpene-induced relaxation was not affected by TEA, a nonselective inhibitor of K+ channels. The KA-acetoxy antagonized CaCl2-induced contractions in a concentration-dependent manner and also inhibited an 80 mM KCl-induced contraction. The KA-acetoxy did not interfere with Ca2+ release from intracellular stores. The vasorelaxant induced by KA-acetoxy seems to involve the inhibition of the Ca2+ influx and also, at least in part, by endothelial muscarinic receptors activation, NO and PGI2 release.

Protective effects of simvastatin on coronary artery function in swine with acute infection

DEFF Research Database (Denmark)

Liuba, Petru; Pesonen, Erkki; Forslid, Anders

2006-01-01

cholesterol) between the groups (p>0.2). CONCLUSION:: Acute infection is associated with impairment of the muscarinic and kinin-related reactivity of coronary circulation. These functional abnormalities are in part prevented by simvastatin through mechanisms unrelated to lipid lowering......BACKGROUND:: The risk for coronary events may rise during acute infection. Perturbation in coronary endothelial function emerges as one important link. We investigated whether simvastatin could protect the coronary arterial function from the adverse effects of acute infection in swine. METHODS......:: Coronary endothelium-dependent and -independent vasomotor responses were assessed by Doppler velocimetry in 12 Chlamydia pneumoniae-infected and 6 sham-infected swine 2 weeks after intratracheal inoculation. Half of animals from the infection group were pre-treated with simvastatin (80mg daily), while...

Uridine Adenosine Tetraphosphate-Induced Coronary Relaxation Is Blunted in Swine With Pressure Overload: A Role for Vasoconstrictor Prostanoids.

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Zhou, Zhichao; Lankhuizen, Inge M; van Beusekom, Heleen M; Cheng, Caroline; Duncker, Dirk J; Merkus, Daphne

2018-01-01

Plasma levels of the vasoactive substance uridine adenosine tetraphosphate (Up 4 A) are elevated in hypertensive patients and Up 4 A-induced vascular contraction is exacerbated in various arteries isolated from hypertensive animals, suggesting a potential role of Up 4 A in development of hypertension. We previously demonstrated that Up 4 A produced potent and partially endothelium-dependent relaxation in the porcine coronary microvasculature. Since pressure-overload is accompanied by structural abnormalities in the coronary microvasculature as well as by endothelial dysfunction, we hypothesized that pressure-overload blunts the coronary vasodilator response to Up 4 A, and that the involvement of purinergic receptors and endothelium-derived factors is altered. The effects of Up 4 A were investigated using wire-myography in isolated coronary small arteries from Sham-operated swine and swine with prolonged (8 weeks) pressure overload of the left ventricle induced by aortic banding (AoB). Expression of purinergic receptors and endothelium-derived factors was assessed in isolated coronary small arteries using real-time PCR. Up 4 A (10 -9 to 10 -5 M) failed to produce contraction in isolated coronary small arteries from either Sham or AoB swine, but produced relaxation in preconstricted arteries, which was significantly blunted in AoB compared to Sham. Blockade of purinergic P1, and P2 receptors attenuated Up 4 A-induced coronary relaxation more, while the effect of P2X 1 -blockade was similar and the effects of A 2A - and P2Y 1 -blockade were reduced in AoB as compared to Sham. mRNA expression of neither A1, A2, A3, nor P2X 1 , P2X 7 , P2Y 1 , P2Y 2 , nor P2Y 6 -receptors was altered in AoB as compared to Sham, while P2Y 12 expression was higher in AoB. eNOS inhibition attenuated Up 4 A-induced coronary relaxation in both Sham and AoB. Additional blockade of cyclooxygenase enhanced Up 4 A-induced coronary relaxation in AoB but not Sham swine, suggesting the involvement

Arginase up-regulation and eNOS uncoupling contribute to impaired endothelium-dependent vasodilation in a rat model of intrauterine growth restriction.

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Grandvuillemin, Isabelle; Buffat, Christophe; Boubred, Farid; Lamy, Edouard; Fromonot, Julien; Charpiot, Philippe; Simoncini, Stephanie; Sabatier, Florence; Dignat-George, Françoise; Peyter, Anne-Christine; Simeoni, Umberto; Yzydorczyk, Catherine

2018-05-09

Individuals born after intrauterine growth restriction (IUGR) are at increased risk of developing cardiovascular diseases in adulthood, notably hypertension (HTN). Alterations in the vascular system, particularly impaired endothelium-dependent vasodilation, may play an important role in long-term effects of IUGR. Whether such vascular dysfunction precedes HTN has not been fully established in individuals born after IUGR. Moreover, the intimate mechanisms of altered endothelium-dependent vasodilation remain incompletely elucidated. We therefore investigated, using a rat model of IUGR, whether impaired endothelium-dependent relaxation precedes the development of HTN and whether key components of the L-Arginine-nitric oxide (NO) pathway are involved in its pathogenesis. Pregnant rats were fed with a control (CTRL, 23% casein) or low-protein diet (LP, 9% casein) to induce IUGR. Systolic blood pressure (SBP) was measured by tail-cuff plethysmography in 5- and 8-week-old male offspring. Aortic rings were isolated to investigate relaxation to acetylcholine, NO production, eNOS protein content, arginase activity, and superoxide anion production. SBP was not different at 5 weeks, but significantly increased in 8-week-old LP vs. CRTL offspring. In 5-week-old LP vs. CRTL males, endothelium-dependent vasorelaxation was significantly impaired, but restored by pre-incubation with L-Arginine or the arginase inhibitor BEC; NO production was significantly reduced, but restored by L-Arginine pretreatment; total eNOS protein, dimer/monomer ratio, and arginase activity were significantly increased; superoxide anion production was significantly enhanced, but normalized by pretreatment with the NOS inhibitor L-NNA. In this model, IUGR leads to early-impaired endothelium-dependent vasorelaxation, resulting from arginase up-regulation and eNOS uncoupling, which precedes the development of HTN.

Deficiency of sex hormones does not affect 17-ß-estradiol-induced coronary vasodilation in the isolated rat heart.

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Santos, R L; Lima, J T; Rouver, W N; Moysés, M R

2016-01-01

The relaxation of coronary arteries by estrogens in the coronary vascular beds of naive and hypertensive rats has been well described. However, little is known about this action in gonadectomized rats. We investigated the effect of 17-ß-estradiol (E2) in coronary arteries from gonadectomized rats, as well as the contributions of endothelium-derived factors and potassium channels. Eight-week-old female and male Wistar rats weighing 220-300 g were divided into sham-operated and gonadectomized groups (n=9-12 animals per group). The baseline coronary perfusion pressure (CPP) was determined, and the vasoactive effects of 10 μM E2 were assessed by bolus administration before and after endothelium denudation or by perfusion with NG-nitro-L-arginine methyl ester (L-NAME), indomethacin, clotrimazole, L-NAME plus indomethacin, L-NAME plus clotrimazole or tetraethylammonium (TEA). The CPP differed significantly between the female and sham-operated male animals. Gonadectomy reduced the CPP only in female rats. Differences in E2-induced relaxation were observed between the female and male animals, but male castration did not alter this response. For both sexes, the relaxation response to E2 was, at least partly, endothelium-dependent. The response to E2 was reduced only in the sham-operated female rats treated with L-NAME. However, in the presence of indomethacin, clotrimazole, L-NAME plus indomethacin or L-NAME plus clotrimazole, or TEA, the E2 response was significantly reduced in all groups. These results highlight the importance of prostacyclin, endothelium-derived hyperpolarizing factor, and potassium channels in the relaxation response of coronary arteries to E2 in all groups, whereas nitric oxide may have had an important role only in the sham-operated female group.

Model of the coronary circulation based on pressure dependence of coronary resistance and compliance

NARCIS (Netherlands)

Bruinsma, P.; Arts, T.; Dankelman, J.; Spaan, J. A.

1988-01-01

The effect of pressure-dependent changes in vascular volume, resistance and capacitance in the coronary micro-circulation, has been studied by a distributed mathematical model of the coronary micro-vasculature in the left ventricular wall. The model does not include regulation of coronary blood flow

Brachial artery vasomotion and transducer pressure effect on measurements by active contour segmentation on ultrasound

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Cary, Theodore W.; Sultan, Laith R.; Sehgal, Chandra M., E-mail: sehgalc@uphs.upenn.edu [Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104 (United States); Reamer, Courtney B.; Mohler, Emile R. [Department of Medicine, Division of Cardiovascular Medicine, Section of Vascular Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104 (United States)

2014-02-15

Purpose: To use feed-forward active contours (snakes) to track and measure brachial artery vasomotion on ultrasound images recorded in both transverse and longitudinal views; and to compare the algorithm's performance in each view. Methods: Longitudinal and transverse view ultrasound image sequences of 45 brachial arteries were segmented by feed-forward active contour (FFAC). The segmented regions were used to measure vasomotion artery diameter, cross-sectional area, and distention both as peak-to-peak diameter and as area. ECG waveforms were also simultaneously extracted frame-by-frame by thresholding a running finite-difference image between consecutive images. The arterial and ECG waveforms were compared as they traced each phase of the cardiac cycle. Results: FFAC successfully segmented arteries in longitudinal and transverse views in all 45 cases. The automated analysis took significantly less time than manual tracing, but produced superior, well-behaved arterial waveforms. Automated arterial measurements also had lower interobserver variability as measured by correlation, difference in mean values, and coefficient of variation. Although FFAC successfully segmented both the longitudinal and transverse images, transverse measurements were less variable. The cross-sectional area computed from the longitudinal images was 27% lower than the area measured from transverse images, possibly due to the compression of the artery along the image depth by transducer pressure. Conclusions: FFAC is a robust and sensitive vasomotion segmentation algorithm in both transverse and longitudinal views. Transverse imaging may offer advantages over longitudinal imaging: transverse measurements are more consistent, possibly because the method is less sensitive to variations in transducer pressure during imaging.

Effect of subchronic exposure to mainstream cigarette smoke on endothelium-dependent vasodilation in rat arteries

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Helena Lenasi

2005-07-01

Full Text Available Background: Cigarette smoking is reported to impair endothelium-dependent vasodilation. The aim of the present study was to assess the effect of 30-day exposure to mainstream cigarette smoke on vascular reactivity of rat abdominal aorta, carotid, renal and mesenteric artery. Separately, the NO-mediated and the EDHF-mediated, endothelium-dependent vascular relaxations were determined.Methods: Two groups of »Whistar Kyoto« rats were exposed to mainstream cigarette smoke (2 hours/day, 5 days/week for 30 days and to fresh conditioned air, respectively. Rats were sacrificed on the second day after the last exposition to cigarette smoke. Vascular reactivity studies were performed on isolated, endothelium-intact, phenylephrine-preconstricted rat artery rings. Cumulative concentration-relaxation curves to acetylcholine (ACh were obtained in the absence and presence of the endothelial NO synthase (eNOS inhibitor N ω nitro L-arginine (L-NA and the cyclo-oxygenase (COX inhibitor diclofenac, respectively. After washing period of 1 hour, vessels were exposed either to the intracellular superoxide scavenger tiron, to the cytochrome P450 (CYP inhibitor miconazole or the Na-K-ATPase inhibitor ouabain before being preconstricted with phenylephrine and determining the concentration-response curve to ACh.Results: ACh induced concentration-dependent relaxations. In none of the vessels investigated did we observe a significant difference in the relaxations obtained in arteries from control rats and rats exposed to cigarettee smoke. Although smoking is known to cause an increase in oxidative stress, treatment of the vessels with tiron did not affect the NOmediated relaxations. To evaluate the contribution of EDHF to endothelium-dependent vasodilation rings were preincubated with L-NA. The EDHF-mediated relaxations were significantly attenuated compared to the NO-mediated relaxations in renal and mesenteric artery and almost completely abolished in aorta and

Endothelium-dependent relaxation and angiotensin II sensitivity in experimental preeclampsia.

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Anne Marijn van der Graaf

Full Text Available OBJECTIVE: We investigated endothelial dysfunction and the role of angiotensin (Ang-II type I (AT1-R and type II (AT2-R receptor in the changes in the Ang-II sensitivity in experimental preeclampsia in the rat. METHODS: Aortic rings were isolated from low dose lipopolysaccharide (LPS infused pregnant rats (experimental preeclampsia; n=9, saline-infused pregnant rats (n=8, and saline (n=8 and LPS (n=8 infused non-pregnant rats. Endothelium-dependent acetylcholine-mediated relaxation was studied in phenylephrine-preconstricted aortic rings in the presence of vehicle, N(G-nitro-L-arginine methyl ester and/or indomethacin. To evaluate the role for AT1-R and AT2-R in Ang-II sensitivity, full concentration response curves were obtained for Ang-II in the presence of losartan or PD123319. mRNA expression of the AT1-R and AT2-R, eNOS and iNOS, COX1 and COX2 in aorta were evaluated using real-time RT-PCR. RESULTS: The role of vasodilator prostaglandins in the aorta was increased and the role of endothelium-derived hyperpolarizing factor and response of the AT1-R and AT2-R to Ang-II was decreased in pregnant saline infused rats as compared with non-pregnant rats. These changes were not observed during preeclampsia. CONCLUSION: Pregnancy induced adaptations in endothelial function, which were not observed in the rat model for preeclampsia. This role of lack of pregnancy induced endothelial adaptation in the pathophysiology of experimental preeclampsia needs further investigation.

Role of endothelium-derived hyperpolarization in the vasodilatation of rat intrarenal arteries

DEFF Research Database (Denmark)

Pinilla, Estéfano; Sánchez-Pina, Ana; Muñoz Picos, Mercedes

2016-01-01

Background and purpose: Endothelium-dependent vasodilation plays an important role in the regulation of vascular tone in different vascular beds. Besides the release of prostacyclin (PGI2) and nitric oxide (NO), the endothelium mediates vasodilation through endothelium-derived hyperpolarization (...

Endothelium-Dependent Vasorelaxant Effect of Butanolic Fraction from Caryocar brasiliense Camb. Leaves in Rat Thoracic Aorta

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Lais Moraes de Oliveira

2012-01-01

Full Text Available Caryocar brasiliense Camb. “pequi” is a native plant from the Cerrado region of Brazil that contains bioactive components reported to be antioxidant agents. Previous work has demonstrated that dietary supplementation with pequi decreased the arterial pressure of volunteer athletes. We found that the crude hydroalcoholic extract (CHE of C. brasiliense leaves relaxed, in a concentration-dependent manner, rat aortic rings precontracted with phenylephrine, and that the butanolic fraction (BF produced an effect similar to that of the CHE. Aortic relaxation induced by BF was abolished by endothelium removal, by incubation of the nitric oxide synthase inhibitor L-NAME, or the soluble guanylatecyclase inhibitor ODQ. However, incubation with atropine and pyrilamine had no effect on the BF-induced vasorelaxation. Moreover, this effect was not inhibited by indomethacin and tetraethylammonium. The concentration-response curve to calcium in denuded-endothelium rings was not modified after incubation with BF, and the vasorelaxation by BF in endothelium-intact rings precontracted with KCl was abolished after incubation with L-NAME. In addition, administration of BF in anesthetized rats resulted in a reversible hypotension. The results reveal that C. brasiliense possesses both in vivo and in vitro activities and that the vascular effect of BF involves stimulation of the nitric oxide/cyclic GMP pathway.

Androgen action via testicular arteriole smooth muscle cells is important for Leydig cell function, vasomotion and testicular fluid dynamics.

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Michelle Welsh

2010-10-01

Full Text Available Regulation of blood flow through the testicular microvasculature by vasomotion is thought to be important for normal testis function as it regulates interstitial fluid (IF dynamics which is an important intra-testicular transport medium. Androgens control vasomotion, but how they exert these effects remains unclear. One possibility is by signalling via androgen receptors (AR expressed in testicular arteriole smooth muscle cells. To investigate this and determine the overall importance of this mechanism in testis function, we generated a blood vessel smooth muscle cell-specific AR knockout mouse (SMARKO. Gross reproductive development was normal in SMARKO mice but testis weight was reduced in adulthood compared to control littermates; this reduction was not due to any changes in germ cell volume or to deficits in testosterone, LH or FSH concentrations and did not cause infertility. However, seminiferous tubule lumen volume was reduced in adult SMARKO males while interstitial volume was increased, perhaps indicating altered fluid dynamics; this was associated with compensated Leydig cell failure. Vasomotion was impaired in adult SMARKO males, though overall testis blood flow was normal and there was an increase in the overall blood vessel volume per testis in adult SMARKOs. In conclusion, these results indicate that ablating arteriole smooth muscle AR does not grossly alter spermatogenesis or affect male fertility but does subtly impair Leydig cell function and testicular fluid exchange, possibly by locally regulating microvascular blood flow within the testis.

Coronary and muscle blood flow during physical exercise in humans; heterogenic alliance.

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Zoladz, Jerzy A; Majerczak, Joanna; Duda, Krzysztof; Chlopicki, Stefan

2015-08-01

In this review, we present the relation between power generation capabilities and pulmonary oxygen uptake during incremental cycling exercise in humans and the effect of exercise intensity on the oxygen cost of work. We also discuss the importance of oxygen delivery to the working muscles as a factor determining maximal oxygen uptake in humans. Subsequently, we outline the importance of coronary blood flow, myocardial oxygen uptake and myocardial metabolic stability for exercise tolerance. Finally, we describe mechanisms of endothelium-dependent regulation of coronary and skeletal muscle blood flow, dysregulation of which may impair exercise capacity and increase the cardiovascular risk of exercise. Copyright © 2015 Institute of Pharmacology, Polish Academy of Sciences. All rights reserved.

Effect of simvastatin on vascular tone in porcine coronary artery: Potential role of the mitochondria

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Almukhtar, H.; Garle, M.J.; Smith, P.A.; Roberts, R.E.

2016-01-01

Statins induce acute vasorelaxation which may contribute to the overall benefits of statins in the treatment of cardiovascular disease. The mechanism underlying this relaxation is unknown. As statins have been shown to alter mitochondrial function, in this study we investigated the role of mitochondria in the relaxation to simvastatin. Relaxation of porcine coronary artery segments by statins was measured using isolated tissue baths. Mitochondrial activity was determined by measuring changes in rhodamine 123 fluorescence. Changes in intracellular calcium levels were determined in freshly isolated smooth muscle cells with Fluo-4 using standard epifluorescent imaging techniques. Simvastatin, but not pravastatin, produced a slow relaxation of the coronary artery, which was independent of the endothelium. The relaxation was attenuated by the mitochondrial complex I inhibitor rotenone (10 μM) and the complex III inhibitor myxothiazol (10 μM), or a combination of the two. The complex III inhibitor antimycin A (10 μM) produced a similar time-dependent relaxation of the porcine coronary artery, which was attenuated by rotenone. Changes in rhodamine 123 fluorescence showed that simvastatin (10 μM) depolarized the membrane potential of mitochondria in both isolated mitochondria and intact blood vessels. Simvastatin and antimycin A both inhibited calcium-induced contractions in isolated blood vessels and calcium influx in smooth muscle cells and this inhibition was prevented by rotenone. In conclusion, simvastatin produces an endothelium-independent relaxation of the porcine coronary artery which is dependent, in part, upon effects on the mitochondria. The effects on the mitochondria may lead to a reduction in calcium influx and hence relaxation of the blood vessel. - Highlights: • Simvastatin produces a relaxation of the porcine coronary artery. • This relaxation is inhibited by mitochondrial complex inhibitors. • Simvastatin alters mitochondrial membrane potential

Effect of simvastatin on vascular tone in porcine coronary artery: Potential role of the mitochondria

Energy Technology Data Exchange (ETDEWEB)

Almukhtar, H.; Garle, M.J.; Smith, P.A.; Roberts, R.E., E-mail: richard.roberts@nottingham.ac.uk

2016-08-15

Statins induce acute vasorelaxation which may contribute to the overall benefits of statins in the treatment of cardiovascular disease. The mechanism underlying this relaxation is unknown. As statins have been shown to alter mitochondrial function, in this study we investigated the role of mitochondria in the relaxation to simvastatin. Relaxation of porcine coronary artery segments by statins was measured using isolated tissue baths. Mitochondrial activity was determined by measuring changes in rhodamine 123 fluorescence. Changes in intracellular calcium levels were determined in freshly isolated smooth muscle cells with Fluo-4 using standard epifluorescent imaging techniques. Simvastatin, but not pravastatin, produced a slow relaxation of the coronary artery, which was independent of the endothelium. The relaxation was attenuated by the mitochondrial complex I inhibitor rotenone (10 μM) and the complex III inhibitor myxothiazol (10 μM), or a combination of the two. The complex III inhibitor antimycin A (10 μM) produced a similar time-dependent relaxation of the porcine coronary artery, which was attenuated by rotenone. Changes in rhodamine 123 fluorescence showed that simvastatin (10 μM) depolarized the membrane potential of mitochondria in both isolated mitochondria and intact blood vessels. Simvastatin and antimycin A both inhibited calcium-induced contractions in isolated blood vessels and calcium influx in smooth muscle cells and this inhibition was prevented by rotenone. In conclusion, simvastatin produces an endothelium-independent relaxation of the porcine coronary artery which is dependent, in part, upon effects on the mitochondria. The effects on the mitochondria may lead to a reduction in calcium influx and hence relaxation of the blood vessel. - Highlights: • Simvastatin produces a relaxation of the porcine coronary artery. • This relaxation is inhibited by mitochondrial complex inhibitors. • Simvastatin alters mitochondrial membrane potential

Ivabradine in acute coronary syndromes: Protection beyond heart rate lowering.

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Niccoli, Giampaolo; Borovac, Josip Anđelo; Vetrugno, Vincenzo; Camici, Paolo G; Crea, Filippo

2017-06-01

Ivabradine is a heart rate reducing agent that exhibits anti-ischemic effects through the inhibition of funny electrical current in the sinus node resulting in heart rate reduction, thus enabling longer diastolic perfusion time, and reduced myocardial oxygen consumption without detrimental changes in arterial blood pressure, coronary vasomotion, and ventricular contractility. The current guideline-based clinical use of Ivabradine is reserved for patients with stable angina pectoris who cannot tolerate or whose symptoms are inadequately controlled with beta blockers. In patients with chronic heart failure and reduced ejection fraction, Ivabradine has demonstrated beneficial effects in improving clinical outcomes when added to conventional therapy. However, the role of Ivabradine in acute coronary syndromes has not been established. Based on the results from some relevant preclinical studies and a limited amount of clinical data that were reported recently, the role of Ivabradine in acute ischemic events warrants further investigation. The aim of this review is to provide an overview of the available literature on the potential role of Ivabradine in the clinical context of acute coronary syndromes. Copyright © 2017 Elsevier B.V. All rights reserved.

Endothelium Protective Function of Statins in Men and Women with Coronary Atherosclerosis

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M. V. Klimushina; N. G. Gumanova; A. Ju. Gorshkov; N. E. Gavrilova; V. A. Metel'skaja; S. A. Boytsov

2016-01-01

Aim. To study the relationship between serum endothelin levels and lipid-lowering therapy in patients with confirmed coronary atherosclerosis.Material and methods. Patients (n=447; 320 men and 127 women; mean age 62.7±8.8 years) with coronary atherosclerosis, confirmed by coronary angiography, were included into the study. Serum endothelin levels were assessed by enzyme immunoassay (ELISA).Results. Negative correlation between the statins receiving and serum endothelin level was found in men ...

Exercise capacity and cardiac hemodynamic response in female ApoE/LDLR−/− mice: a paradox of preserved V’O2max and exercise capacity despite coronary atherosclerosis

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Wojewoda, M.; Tyrankiewicz, U.; Gwozdz, P.; Skorka, T.; Jablonska, M.; Orzylowska, A.; Jasinski, K.; Jasztal, A.; Przyborowski, K.; Kostogrys, R. B.; Zoladz, J. A.; Chlopicki, S.

2016-01-01

We assessed exercise performance, coronary blood flow and cardiac reserve of female ApoE/LDLR−/− mice with advanced atherosclerosis compared with age-matched, wild-type C57BL6/J mice. Exercise capacity was assessed as whole body maximal oxygen consumption (V’O2max), maximum running velocity (vmax) and maximum distance (DISTmax) during treadmill exercise. Cardiac systolic and diastolic function in basal conditions and in response to dobutamine (mimicking exercise-induced cardiac stress) were assessed by Magnetic Resonance Imaging (MRI) in vivo. Function of coronary circulation was assessed in isolated perfused hearts. In female ApoE/LDLR−/− mice V’O2max, vmax and DISTmax were not impaired as compared with C57BL6/J mice. Cardiac function at rest and systolic and diastolic cardiac reserve were also preserved in female ApoE/LDLR−/− mice as evidenced by preserved fractional area change and similar fall in systolic and end diastolic area after dobutamine. Moreover, endothelium-dependent responses of coronary circulation induced by bradykinin (Bk) and acetylcholine (ACh) were preserved, while endothelium-independent responses induced by NO-donors were augmented in female ApoE/LDLR−/− mice. Basal COX-2-dependent production of 6-keto-PGF1α was increased. Concluding, we suggest that robust compensatory mechanisms in coronary circulation involving PGI2- and NO-pathways may efficiently counterbalance coronary atherosclerosis-induced impairment in V’O2max and exercise capacity. PMID:27108697

Tetrahydrobiopterin restores impaired coronary microvascular dysfunction in hypercholesterolaemia

Energy Technology Data Exchange (ETDEWEB)

Wyss, Christophe A.; Koepfli, Pascal; Namdar, Mehdi; Siegrist, Patrick T.; Kaufmann, Philipp A. [University Hospital, Nuclear Cardiology, Cardiovascular Center, Zurich (Switzerland); Luscher, Thomas F. [University Hospital, Division of Cardiology, Cardiovascular Center, Zurich (Switzerland); Camici, Paolo G. [Hammersmith Hospital, MRC Clinical Sciences Centre, Faculty of Medicine, Imperial College of Science, Technology and Medicine, London (United Kingdom)

2005-01-01

Tetrahydrobiopterin (BH{sub 4}) is an essential co-factor for the synthesis of nitric oxide (NO), and BH{sub 4} deficiency may cause impaired NO synthase (NOS) activity. We studied whether BH{sub 4} deficiency contributes to the coronary microcirculatory dysfunction observed in patients with hypercholesterolaemia. Myocardial blood flow (MBF; ml min{sup -1} g{sup -1}) was measured at rest, during adenosine-induced (140 {mu}g kg{sup -1} min{sup -1} over 7 min) hyperaemia (mainly non-endothelium dependent) and immediately after supine bicycle exercise (endothelium-dependent) stress in ten healthy volunteers and in nine hypercholesterolaemic subjects using {sup 15}O-labelled water and positron emission tomography. Measurements were repeated 60 min later, after intravenous infusion of BH{sub 4} (10 mg kg{sup -1} body weight over 30 min). Adenosine-induced hyperaemic MBF is considered to represent (near) maximal flow. Flow reserve utilisation was calculated as the ratio of exercise-induced to adenosine-induced hyperaemic MBF and expressed as percent to indicate how much of the maximal (adenosine-induced) hyperaemia can be achieved by bicycle stress. BH{sub 4} increased exercise-induced hyperaemia in controls (2.96{+-}0.58 vs 3.41{+-}0.73 ml min{sup -1} g{sup -1}, p<0.05) and hypercholesterolaemic subjects (2.47{+-}0.78 vs 2.70{+-}0.72 ml min{sup -1} g{sup -1}, p<0.01) but had no influence on MBF at rest or during adenosine-induced hyperaemia in controls (4.52{+-}1.10 vs 4.85{+-}0.45 ml min{sup -1} g{sup -1}, p=NS) or hypercholesterolaemic subjects (4.86{+-}1.18 vs 4.53{+-}0.93 ml min{sup -1} g{sup -1}, p=NS). Flow reserve utilisation remained unchanged in controls (70{+-}17% vs 71{+-}19%, p=NS) but increased significantly in hypercholesterolaemic subjects (53{+-}15% vs 66{+-}14%, p<0.05). BH{sub 4} restores flow reserve utilisation of the coronary microcirculation in hypercholesterolaemic subjects, suggesting that BH{sub 4} deficiency may contribute to coronary

Activation of eNOS by D-pinitol Induces an Endothelium-Dependent Vasodilatation in Mouse Mesenteric Artery

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Luciana N. Moreira

2018-05-01

Full Text Available D-pinitol is a cyclitol present in several edible plant species and extensively investigated for the treatment of metabolic diseases in humans, as food supplement, and demonstrated protective effects in the cardiovascular system. For these reasons, the present work aimed at investigating the mechanisms involved in the vascular effects of D-pinitol in mouse mesenteric artery. Mesenteric arteries from male C57BL/6 mice were mounted in a wire myograph. Nitrite was measured by the 2,3-diaminonaphthalene (DAN method. Protein expression and phosphorylation were measured by Western blot. The systolic blood pressure (SBP was measured by tail-cuff plethysmography. D-pinitol induced a concentration-dependent vasodilatation in endothelium-intact, but not in endothelium-denuded arteries. Nω-Nitro-L-arginine methyl ester (300 μM abolished the effect of D-pinitol, while 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ; 10 μM shifted the concentration-response curve to the right. KN-93 (1 μM blunted the vasodilator effect of D-pinitol, but H-89 (0.1 μM did not change it. 1-[2-(Trifluoromethyl phenyl]imidazole (300 μM, indomethacin (10 μM, celecoxib (5 μM, wortmannin (1 μM, ruthenium red (10 μM, tiron (10 μM, MnTMPyP (30 μM, MPP (0.1 μM, PHTPP (0.1 μM, and atropine (1 μM did not change the effect of D-pinitol. D-pinitol increased the concentration of nitrite, which was inhibited by L-NAME and calmidazolium (10 μM. D-pinitol increased the phosphorylation level of eNOS activation site at Ser1177 and reduced the phosphorylation level of its inactivation site at Thr495. In normotensive mice, the intraperitoneal administration of D-pinitol (10 mg/kg induced a significant reduction of the SBP after 30 min. The present results led us to conclude that D-pinitol has an endothelium- and NO-dependent vasodilator effect in mouse mesenteric artery through a mechanism dependent on the activation of eNOS by the calcium-calmodulin complex, which can explain its

Association of Adventitial Vasa Vasorum and Inflammation With Coronary Hyperconstriction After Drug-Eluting Stent Implantation in Pigs In Vivo.

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Nishimiya, Kensuke; Matsumoto, Yasuharu; Shindo, Tomohiko; Hanawa, Kenichiro; Hasebe, Yuhi; Tsuburaya, Ryuji; Shiroto, Takashi; Takahashi, Jun; Ito, Kenta; Ishibashi-Ueda, Hatsue; Yasuda, Satoshi; Shimokawa, Hiroaki

2015-01-01

The importance of adventitial inflammation has been implicated for the pathogenesis of coronary artery disease. However, the roles of adventitial changes in drug-eluting stent (DES)-induced coronary hyperconstriction remain largely unknown. In the present study, this issue in pigs in vivo with a special reference to adventitial vasa vasorum (VV) formation and Rho-kinase activation, a central mechanism of coronary vasospasm, was examined. Each animal received a sirolimus-eluting stent (SES) and a biolimus A9-eluting stent (BES), one in the left anterior descending and another in the left circumflex coronary arteries in a randomized manner (n=18). After 1, 3 and 6 months, coronary vasomotion was examined. At 1 month, coronary vasoconstriction to serotonin was significantly enhanced at the SES edges as compared with the BES edges (SES, 52±7% vs. BES, 22±3%, Pmicro-CT showed VV augmentation at the SES site, extending to the proximal and distal edges. Immunostainings demonstrated that VV formation, macrophage infiltration in the adventitia and Rho-kinase expressions/activation were significantly enhanced at the SES edges as compared with the BES edges. The DES with durable polymers enhances VV formation and inflammation in the adventitia, associating with the pathogenesis of DES-induced coronary hyperconstriction through Rho-kinase activation in pigs in vivo.

Short- and long-term black tea consumption reverses endothelial dysfunction in patients with coronary artery disease.

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Duffy, S J; Keaney , J F; Holbrook, M; Gokce, N; Swerdloff, P L; Frei, B; Vita, J A

2001-07-10

Epidemiological studies suggest that tea consumption decreases cardiovascular risk, but the mechanisms of benefit remain undefined. Endothelial dysfunction has been associated with coronary artery disease and increased oxidative stress. Some antioxidants have been shown to reverse endothelial dysfunction, and tea contains antioxidant flavonoids. Methods and Results-- To test the hypothesis that tea consumption will reverse endothelial dysfunction, we randomized 66 patients with proven coronary artery disease to consume black tea and water in a crossover design. Short-term effects were examined 2 hours after consumption of 450 mL tea or water. Long-term effects were examined after consumption of 900 mL tea or water daily for 4 weeks. Vasomotor function of the brachial artery was examined at baseline and after each intervention with vascular ultrasound. Fifty patients completed the protocol and had technically suitable ultrasound measurements. Both short- and long-term tea consumption improved endothelium- dependent flow-mediated dilation of the brachial artery, whereas consumption of water had no effect (Peffect on endothelium-independent nitroglycerin-induced dilation. An equivalent oral dose of caffeine (200 mg) had no short-term effect on flow-mediated dilation. Plasma flavonoids increased after short- and long-term tea consumption. Short- and long-term black tea consumption reverses endothelial vasomotor dysfunction in patients with coronary artery disease. This finding may partly explain the association between tea intake and decreased cardiovascular disease events.

Oxidant-NO dependent gene regulation in dogs with type I diabetes: impact on cardiac function and metabolism

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Ojaimi Caroline

2010-08-01

Full Text Available Abstract Background The mechanisms responsible for the cardiovascular mortality in type I diabetes (DM have not been defined completely. We have shown in conscious dogs with DM that: 1 baseline coronary blood flow (CBF was significantly decreased, 2 endothelium-dependent (ACh coronary vasodilation was impaired, and 3 reflex cholinergic NO-dependent coronary vasodilation was selectively depressed. The most likely mechanism responsible for the depressed reflex cholinergic NO-dependent coronary vasodilation was the decreased bioactivity of NO from the vascular endothelium. The goal of this study was to investigate changes in cardiac gene expression in a canine model of alloxan-induced type 1 diabetes. Methods Mongrel dogs were chronically instrumented and the dogs were divided into two groups: one normal and the other diabetic. In the diabetic group, the dogs were injected with alloxan monohydrate (40-60 mg/kg iv over 1 min. The global changes in cardiac gene expression in dogs with alloxan-induced diabetes were studied using Affymetrix Canine Array. Cardiac RNA was extracted from the control and DM (n = 4. Results The array data revealed that 797 genes were differentially expressed (P 2+ cycling genes (ryanodine receptor; SERCA2 Calcium ATPase, structural proteins (actin alpha. Of particular interests are genes involved in glutathione metabolism (glutathione peroxidase 1, glutathione reductase and glutathione S-transferase, which were markedly down regulated. Conclusion our findings suggest that type I diabetes might have a direct effect on the heart by impairing NO bioavailability through oxidative stress and perhaps lipid peroxidases.

cIMP synthesized by sGC as a mediator of hypoxic contraction of coronary arteries.

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Chen, Zhengju; Zhang, Xu; Ying, Lei; Dou, Dou; Li, Yanhui; Bai, Yun; Liu, Juan; Liu, Limei; Feng, Han; Yu, Xiaoxing; Leung, Susan Wai-Sum; Vanhoutte, Paul M; Gao, Yuansheng

2014-08-01

cGMP is considered the only mediator synthesized by soluble guanylyl cyclase (sGC) in response to nitric oxide (NO). However, purified sGC can synthesize several other cyclic nucleotides, including inosine 3',5'-cyclic monophosphate (cIMP). The present study was designed to determine the role of cIMP in hypoxic contractions of isolated porcine coronary arteries. Vascular responses were examined by measuring isometric tension. Cyclic nucleotides were assayed by HPLC tandem mass spectroscopy. Rho kinase (ROCK) activity was determined by measuring the phosphorylation of myosin phosphatase target subunit 1 using Western blot analysis and an ELISA kit. The level of cIMP, but not that of cGMP, was elevated by hypoxia in arteries with, but not in those without, endothelium [except if treated with diethylenetriamine (DETA) NONOate]; the increases in cIMP were inhibited by the sGC inhibitor 1H-[1,2,4]oxadiazolo[4,3,-a]quinoxalin-1-one (ODQ). Hypoxia (Po2: 25-30 mmHg) augmented contractions of arteries with and without endothelium if treated with DETA NONOate; these hypoxic contractions were blocked by ODQ. In arteries without endothelium, hypoxic augmentation of contraction was also obtained with exogenous cIMP. In arteries with endothelium, hypoxic augmentation of contraction was further enhanced by inosine 5'-triphosphate, the precursor for cIMP. The augmentation of contraction caused by hypoxia or cIMP was accompanied by increased phosphorylation of myosin phosphatase target subunit 1 at Thr(853), which was prevented by the ROCK inhibitor Y-27632. ROCK activity in the supernatant of isolated arteries was stimulated by cIMP in a concentration-dependent fashion. These results demonstrate that cIMP synthesized by sGC is the likely mediator of hypoxic augmentation of coronary vasoconstriction, in part by activating ROCK. Copyright © 2014 the American Physiological Society.

Inhibition of PKC-dependent extracellular Ca2+ entry contributes to the depression of contractile activity in long-term pressure-overloaded endothelium-denuded rat aortas

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Padilla, J.; López, R.M.; López, P.; Castillo, M.C.; Querejeta, E.; Ruiz, A.; Castillo, E.F.

2014-01-01

We examined the contractile responsiveness of rat thoracic aortas under pressure overload after long-term suprarenal abdominal aortic coarctation (lt-Srac). Endothelium-dependent angiotensin II (ANG II) type 2 receptor (AT 2 R)-mediated depression of contractions to ANG II has been reported in short-term (1 week) pressure-overloaded rat aortas. Contractility was evaluated in the aortic rings of rats subjected to lt-Srac or sham surgery (Sham) for 8 weeks. ANG I and II levels and AT 2 R protein expression in the aortas of lt-Srac and Sham rats were also evaluated. lt-Srac attenuated the contractions of ANG II and phenylephrine in the aortas in an endothelium-independent manner. However, lt-Srac did not influence the transient contractions induced in endothelium-denuded aortic rings by ANG II, phenylephrine, or caffeine in Ca 2+ -free medium or the subsequent tonic constrictions induced by the addition of Ca 2+ in the absence of agonists. Thus, the contractions induced by Ca 2+ release from intracellular stores and Ca 2+ influx through stored-operated channels were not inhibited in the aortas of lt-Srac rats. Potassium-elicited contractions in endothelium-denuded aortic rings of lt-Srac rats remained unaltered compared with control tissues. Consequently, the contractile depression observed in aortic tissues of lt-Srac rats cannot be explained by direct inhibition of voltage-operated Ca 2+ channels. Interestingly, 12-O-tetradecanoylphorbol-13-acetate-induced contractions in endothelium-denuded aortic rings of lt-Srac rats were depressed in the presence but not in the absence of extracellular Ca 2+ . Neither levels of angiotensins nor of AT 2 R were modified in the aortas after lt-Srac. The results suggest that, in rat thoracic aortas, lt-Srac selectively inhibited protein kinase C-mediated activation of contraction that is dependent on extracellular Ca 2+ entry

Leptin-induced endothelium-dependent vasorelaxation of peripheral arteries in lean and obese rats: role of nitric oxide and hydrogen sulfide.

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Anna Jamroz-Wiśniewska

Full Text Available Adipose tissue hormone leptin induces endothelium-dependent vasorelaxation mediated by nitric oxide (NO and endothelium-derived hyperpolarizing factors (EDHF. Previously it has been demonstrated that in short-term obesity the NO-dependent and the EDHF-dependent components of vascular effect of leptin are impaired and up-regulated, respectively. Herein we examined the mechanism of the EDHF-dependent vasodilatory effect of leptin and tested the hypothesis that alterations of acute vascular effects of leptin in obesity are accounted for by chronic hyperleptinemia. The study was performed in 5 groups of rats: (1 control, (2 treated with exogenous leptin for 1 week to induce hyperleptinemia, (3 obese, fed highly-palatable diet for 4 weeks, (4 obese treated with pegylated superactive rat leptin receptor antagonist (PEG-SRLA for 1 week, (5 fed standard chow and treated with PEG-SRLA. Acute effect of leptin on isometric tension of mesenteric artery segments was measured ex vivo. Leptin relaxed phenylephrine-preconstricted vascular segments in NO- and EDHF-dependent manner. The NO-dependent component was impaired and the EDHF-dependent component was increased in the leptin-treated and obese groups and in the latter group both these effects were abolished by PEG-SRLA. The EDHF-dependent vasodilatory effect of leptin was blocked by either the inhibitor of cystathionine γ-lyase, propargylglycine, or a hydrogen sulfide (H2S scavenger, bismuth (III subsalicylate. The results indicate that NO deficiency is compensated by the up-regulation of EDHF in obese rats and both effects are accounted for by chronic hyperleptinemia. The EDHF-dependent component of leptin-induced vasorelaxation is mediated, at least partially, by H2S.

What can we learn about treating heart failure from the heart's response to acute exercise? Focus on the coronary microcirculation.

Science.gov (United States)

Heinonen, Ilkka; Sorop, Oana; de Beer, Vincent J; Duncker, Dirk J; Merkus, Daphne

2015-10-15

Coronary microvascular function and cardiac function are closely related in that proper cardiac function requires adequate oxygen delivery through the coronary microvasculature. Because of the close proximity of cardiomyocytes and coronary microvascular endothelium, cardiomyocytes not only communicate their metabolic needs to the coronary microvasculature, but endothelium-derived factors also directly modulate cardiac function. This review summarizes evidence that the myocardial oxygen balance is disturbed in the failing heart because of increased extravascular compressive forces and coronary microvascular dysfunction. The perturbations in myocardial oxygen balance are exaggerated during exercise and are due to alterations in neurohumoral influences, endothelial function, and oxidative stress. Although there is some evidence from animal studies that the myocardial oxygen balance can partly be restored by exercise training, it is largely unknown to what extent the beneficial effects of exercise training include improvements in endothelial function and/or oxidative stress in the coronary microvasculature and how these improvements are impacted by risk factors such as diabetes, obesity, and hypercholesterolemia. Copyright © 2015 the American Physiological Society.

Endothelium-dependent relaxation of rat aorta to a histamine H3 agonist is reduced by inhibitors of nitric oxide synthase, guanylate cyclase and Na+,K+-ATPase

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D. M. Djuric

1996-01-01

Full Text Available The possible involvement of different effector systems (nitric oxide synthase, guanylate cyclase, β-adrenergic and muscarinic cholinergic receptors, cyclooxygenase and lipoxygenase, and Na+,K+-ATPase was evaluated in a histamine H3 receptor agonist-induced ((Rα-methylhistamine, (Rα-MeHA endothelium-dependent rat aorta relaxation assay. (Rα-MeHA (0.1 nM – 0.01 mM relaxed endothelium-dependent rat aorta, with a pD2 value of 8.22 ± 0.06, compared with a pD2 value of 7.98 ± 0.02 caused by histamine (50% and 70% relaxation, respectively. The effect of (Rα-MeHA (0.1 nM – 0.01 mM was competitively antagonized by thioperamide (1, 10 and 30 nM (pA2 = 9.21 ± 0.40; slope = 1.03 ± 0.35 but it was unaffected by pyrilamine (100 nM, cimetidine (1 μM, atropine (10 μM, propranolol (1 μM, indomethacin (10 μM or nordthydroguaiaretic acid (0.1 mM. Inhibitors of nitric oxide synthase, L-NG-monomethylarginine (L-NMMA, 10 μM and NG-nitro-L-arginine methylester (L-NOARG, 10 μM inhibited the relaxation effect of (Rα-MeHA, by approximately 52% and 70%, respectively. This inhibitory effect of L-NMMA was partially reversed by L-arginine (10 μM. Methylene blue (10 μM and ouabain (10 μM inhibited relaxation (Rα-MeHA-induced by approximately 50% and 90%, respectively. The products of cyclooxygenase and lipoxygenase are not involved in (Rα-MeHA-induced endothelium-dependent rat aorta relaxation nor are the muscarinic cholinergic and β-adrenergic receptors. The results also suggest the involvement of NO synthase, guanylate cyclase and Na+,K+-ATPase in (Rα-MeHA-induced endothelium-dependent rat aorta relaxation.

Hyperglycaemia-induced impairment of endothelium-dependent vasorelaxation in rat mesenteric arteries is mediated by intracellular methylglyoxal levels in a pathway dependent on oxidative stress

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Brouwers, O; Niessen, P M; Haenen, G

2010-01-01

-hydro-5-methylimidazolone (MG-H1) was detected with an antibody against MG-H1 and quantified with ultra-performance liquid chromatography (tandem) mass spectrometry. Reactive oxygen species formation was measured with a 5-(and-6)-chloromethyl-2'7'-dichlorodihydrofluorescein diacetate acetyl ester probe...... for AGE ligand S100b did (p cells and adventitia by fivefold accompanied by an eightfold increase in the oxidative stress marker nitrotyrosine. Antioxidant pre-incubation prevented methylglyoxal......-induced impairment of vasoreactivity. CONCLUSIONS/INTERPRETATION: These data show that hyperglycaemia-induced impairment of endothelium-dependent vasorelaxation is mediated by increased intracellular methylglyoxal levels in a pathway dependent on oxidative stress....

Tocotrienol rich tocomin attenuates oxidative stress and improves endothelium-dependent relaxation in aortae from rats fed a high-fat western diet

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Saher F Ali

2016-10-01

Full Text Available We have previously reported that tocomin, a mixture high in tocotrienol content and also containing tocopherol, acutely preserves endothelial function in the presence of oxidative stress. In this study we investigated whether tocomin treatment would preserve endothelial function in aortae isolated from rats fed a high fat diet known to cause oxidative stress. Wistar hooded rats were fed a western diet (WD, 21% fat or control rat chow (SD, 6% fat for 12 weeks. Tocomin (40 mg/kg/day sc or its vehicle (peanut oil was administered for the last 4 weeks of the feeding regime. Aortae from WD rats showed an impairment of endothelium-dependent relaxation that was associated with an increased expression of the NADPH oxidase Nox2 subunit and an increase in the vascular generation of superoxide measured using L-012 chemiluminescence. The increase in vascular oxidative stress was accompanied by a decrease in basal NO release and impairment of the contribution of NO to ACh-induced relaxation. The impaired relaxation is likely contributed to by a decreased expression of eNOS, calmodulin and phosphorylated Akt and an increase in caveolin-Tocotrienol rich tocomin, which prevented the diet-induced changes in vascular function, reduced vascular superoxide production and abolished the diet-induced changes in eNOS and other protein expression. Using selective inhibitors of nitric oxide synthase (NOS, soluble guanylate cyclase (sGC and calcium activated potassium (KCa channels we demonstrated that tocomin increased NO mediated relaxation, without affecting the contribution of endothelium-dependent hyperpolarization type relaxation to the endothelium-dependent relaxation. The beneficial actions of tocomin in this diet-induced model of obesity suggests that it may have potential to be used as a therapeutic agent to prevent vascular disease in obesity.

Effects of sapropterin on endothelium-dependent vasodilation in patients with CADASIL: a randomized controlled trial.

Science.gov (United States)

De Maria, Renata; Campolo, Jonica; Frontali, Marina; Taroni, Franco; Federico, Antonio; Inzitari, Domenico; Tavani, Alessandra; Romano, Silvia; Puca, Emanuele; Orzi, Francesco; Francia, Ada; Mariotti, Caterina; Tomasello, Chiara; Dotti, Maria Teresa; Stromillo, Maria Laura; Pantoni, Leonardo; Pescini, Francesca; Valenti, Raffaella; Pelucchi, Claudio; Parolini, Marina; Parodi, Oberdan

2014-10-01

Cerebral autosomal-dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), a rare autosomal dominant disorder caused by NOTCH3 mutations, is characterized by vascular smooth muscle and endothelial cells abnormalities, altered vasoreactivity, and recurrent lacunar infarcts. Vasomotor function may represent a key factor for disease progression. Tetrahydrobiopterin, essential cofactor for nitric oxide synthesis in endothelial cells, ameliorates endothelial function. We assessed whether supplementation with sapropterin, a synthetic tetrahydrobiopterin analog, improves endothelium-dependent vasodilation in CADASIL patients. In a 24-month, multicenter randomized, double-blind, placebo-controlled trial, CADASIL patients aged 30 to 65 years were randomly assigned to receive placebo or sapropterin 200 to 400 mg BID. The primary end point was change in the reactive hyperemia index by peripheral arterial tonometry at 24 months. We also assessed the safety and tolerability of sapropterin. Analysis was done by intention-to-treat. The intention-to-treat population included 61 patients. We found no significant difference between sapropterin (n=32) and placebo (n=29) in the primary end point (mean difference in reactive hyperemia index by peripheral arterial tonometry changes 0.19 [95% confidence interval, -0.18, 0.56]). Reactive hyperemia index by peripheral arterial tonometry increased after 24 months in 37% of patients on sapropterin and in 28% on placebo; however, after adjustment for age, sex, and clinical characteristics, improvement was not associated with treatment arm. The proportion of patients with adverse events was similar on sapropterin and on placebo (50% versus 48.3%); serious adverse events occurred in 6.3% versus 13.8%, respectively. Sapropterin was safe and well-tolerated at the average dose of 5 mg/kg/day, but did not affect endothelium-dependent vasodilation in CADASIL patients. https://www.clinicaltrialsregister.eu. Unique

Ethanol extract of seeds of Oenothera odorata induces vasorelaxation via endothelium-dependent NO-cGMP signaling through activation of Akt-eNOS-sGC pathway.

Science.gov (United States)

Kim, Hye Yoom; Oh, Hyuncheol; Li, Xiang; Cho, Kyung Woo; Kang, Dae Gill; Lee, Ho Sub

2011-01-27

The vasorelaxant effect of ethanol extract of seeds of Oenothera odorata (Onagraceae) (one species of evening primroses) (ESOO) and its mechanisms involved were defined. Changes in vascular tension, guanosine 3',5'-cyclic monophosphate (cGMP) levels, and Akt expression were measured in carotid arterial rings from rats. Seeds of Oenothera odorata were extracted with ethanol (94%) and the extract was filtered, concentrated and stored at -70°C. ESOO relaxed endothelium-intact, but not endothelium-denuded, carotid arterial rings in a concentration-dependent manner. Similarly, ESOO increased cGMP levels of the carotid arterial rings. Pretreatment of endothelium-intact arterial rings with L-NAME, an inhibitor of nitric oxide synthase (NOS), or ODQ, an inhibitor of soluble guanylyl cyclase (sGC), blocked the ESOO-induced vasorelaxation and increase in cGMP levels. Nominally Ca(2+)-free but not L-typed Ca(2+) channel inhibition attenuated the ESOO-induced vasorelaxation. Thapsigargin, Gd(3+), and 2-aminoethyl diphenylborinate, modulators of store-operated Ca(2+) entry (SOCE), significantly attenuated the ESOO-induced vasorelaxation and increase in cGMP levels. Further, wortmannin, an inhibitor of Akt, attenuated the ESOO-induced vasorelaxation and increases in cGMP levels and phosphorylated Akt2 expression. K(+) channel blockade with TEA, 4-aminopyridine, and glibenclamide attenuated the ESOO-induced vascular relaxation. Taken together, the present study demonstrates that ESOO relaxes vascular smooth muscle via endothelium-dependent NO-cGMP signaling through activation of the Akt-eNOS-sGC pathway. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

Factor VIII-associated antigen in human lymphatic endothelium.

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Nagle, R B; Witte, M H; Martinez, A P; Witte, C L; Hendrix, M J; Way, D; Reed, K

1987-03-01

Lymphatic vascular endothelium both on tissue section and in culture exhibits positivity for Factor VIII-associated antigen although staining is generally less intense and more spotty than in comparable blood vascular endothelium. Lymphatic endothelium also exhibits Weibel-Palade bodies. Neither marker, therefore, reliably distinguishes blood vascular endothelium from lymphatic endothelium.

Na,K-ATPase regulates intercellular communication in the vascular wall via cSrc kinase dependent connexin43 phosphorylation

DEFF Research Database (Denmark)

Hangaard, Lise; Bouzinova, Elena; Stæhr, Christian Albeck

2017-01-01

Communication between vascular smooth muscle cells (VSMCs) is dependent on gap junctions and is regulated by the Na-K-ATPase. The Na-K-ATPase is therefore important for synchronized VSMC oscillatory activity, i.e., vasomotion. The signaling between the Na-K-ATPase and gap junctions is unknown. We...... coupling in rat mesenteric small arteries in vitro. Phosphorylation of cSrc kinase and connexin43 (Cx43) were semiquantified by Western blotting. Micromole concentration of ouabain reduced the amplitude of norepinephrine-induced vasomotion and desynchronized Ca2+ transients in VSMC in the arterial wall...

P2X1 receptors and the endothelium

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LS Harrington

2005-03-01

Full Text Available Adenosine triphosphate (ATP is now established as a principle vaso-active mediator in the vasculature. Its actions on arteries are complex, and are mediated by the P2X and P2Y receptor families. It is generally accepted that ATP induces a bi-phasic response in arteries, inducing contraction via the P2X and P2Y receptors on the smooth muscle cells, and vasodilation via the actions of P2Y receptors located on the endothelium. However, a number of recent studies have placed P2X1 receptors on the endothelium of some arteries. The use of a specific P2X1 receptor ligand, a, b methylene ATP has demonstrated that P2X1 receptors also have a bi-functional role. The actions of ATP on P2X1 receptors is therefore dependant on its location, inducing contraction when located on the smooth muscle cells, and dilation when expressed on the endothelium, comparable to that of P2Y receptors.

Inhibition of PKC-dependent extracellular Ca{sup 2+} entry contributes to the depression of contractile activity in long-term pressure-overloaded endothelium-denuded rat aortas

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Padilla, J.; López, R.M.; López, P.; Castillo, M.C.; Querejeta, E.; Ruiz, A.; Castillo, E.F. [Sección de Estudios de Posgrado e Investigación, Escuela Superior de Medicina, Instituto Politécnico Nacional, México, DF (Mexico)

2014-08-01

We examined the contractile responsiveness of rat thoracic aortas under pressure overload after long-term suprarenal abdominal aortic coarctation (lt-Srac). Endothelium-dependent angiotensin II (ANG II) type 2 receptor (AT{sub 2}R)-mediated depression of contractions to ANG II has been reported in short-term (1 week) pressure-overloaded rat aortas. Contractility was evaluated in the aortic rings of rats subjected to lt-Srac or sham surgery (Sham) for 8 weeks. ANG I and II levels and AT{sub 2}R protein expression in the aortas of lt-Srac and Sham rats were also evaluated. lt-Srac attenuated the contractions of ANG II and phenylephrine in the aortas in an endothelium-independent manner. However, lt-Srac did not influence the transient contractions induced in endothelium-denuded aortic rings by ANG II, phenylephrine, or caffeine in Ca{sup 2+}-free medium or the subsequent tonic constrictions induced by the addition of Ca{sup 2+} in the absence of agonists. Thus, the contractions induced by Ca{sup 2+} release from intracellular stores and Ca{sup 2+} influx through stored-operated channels were not inhibited in the aortas of lt-Srac rats. Potassium-elicited contractions in endothelium-denuded aortic rings of lt-Srac rats remained unaltered compared with control tissues. Consequently, the contractile depression observed in aortic tissues of lt-Srac rats cannot be explained by direct inhibition of voltage-operated Ca{sup 2+} channels. Interestingly, 12-O-tetradecanoylphorbol-13-acetate-induced contractions in endothelium-denuded aortic rings of lt-Srac rats were depressed in the presence but not in the absence of extracellular Ca{sup 2+}. Neither levels of angiotensins nor of AT{sub 2}R were modified in the aortas after lt-Srac. The results suggest that, in rat thoracic aortas, lt-Srac selectively inhibited protein kinase C-mediated activation of contraction that is dependent on extracellular Ca{sup 2+} entry.

[The endothelium injuries caused by homocysteine and treatmental effects of Tongxinluo powder].

Science.gov (United States)

Liang, Jun-Qing; Wu, Yi-Ling; Xu, Hai-Bo; Zhao, Shao-Hua; Jia, Zhen-Hua; Zhang, Qiu-Yan; Wei, Cong; Dong, Xiao-Wei

2008-02-01

To observe the effect of homocysteine (HCY) on the function of endothelium cell, and to discuss the possible mechanisms that Tongxinluo super powder affected. Healthy male Wistar rats were divided into randomly the control group, the model group, the Tongxinluo group. The effect of Ach on isolated rat thoracic aorta in vitro was examined, the microcirculation was observed by microcirculation meter, the activity of SOD and GSH-PX and content of NO, MDA, ET, Ang II, TXA2, PGI2 was detected. Compared with control group, the effect of Ach on isolated rat thoracic aorta in vitro weakened markablely (P homocystein might cause the contracted and dilated function decreased, it might get involved in endothelium disfunction as a result of the massive free radicals production and diastolic-contract factors balance disorder induced by high homocystein. (2) Tongxinluo powder could improve the function of endothelium-dependment dilation induced by high homocystein, that associated with inhibitting the excessive production of free radicals, and improved function of endothelium.

Polydatin Restores Endothelium-Dependent Relaxation in Rat Aorta Rings Impaired by High Glucose: A Novel Insight into the PPARβ-NO Signaling Pathway.

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Yang Wu

Full Text Available Polydatin, a natural component from Polygonum Cuspidatum, has important therapeutic effects on metabolic syndrome. A novel therapeutic strategy using polydatin to improve vascular function has recently been proposed to treat diabetes-related cardiovascular complications. However, the biological role and molecular basis of polydatin's action on vascular endothelial cells (VECs-mediated vasodilatation under diabetes-related hyperglycemia condition remain elusive. The present study aimed to assess the contribution of polydatin in restoring endothelium-dependent relaxation and to determine the details of its underlying mechanism. By measuring endothelium-dependent relaxation, we found that acetylcholine-induced vasodilation was impaired by elevated glucose (55 mmol/L; however, polydatin (1, 3, 10 μmol/L could restore the relaxation in a dose-dependent manner. Polydatin could also improve the histological damage to endothelial cells in the thoracic aorta. Polydatin's effects were mediated via promoting the expression of endothelial NO synthase (eNOS, enhancing eNOS activity and decreasing the inducible NOS (iNOS level, finally resulting in a beneficial increase in NO release, which probably, at least in part, through activation of the PPARβ signaling pathway. The results provided a novel insight into polydatin action, via PPARβ-NO signaling pathways, in restoring endothelial function in high glucose conditions. The results also indicated the potential utility of polydatin to treat diabetes related cardiovascular diseases.

The human coronary vasodilatory response to acute mental stress is mediated by neuronal nitric oxide synthase

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Khan, Sitara G.; Melikian, Narbeh; Shabeeh, Husain; Cabaco, Ana R.; Martin, Katherine; Khan, Faisal; O’Gallagher, Kevin; Chowienczyk, Philip J.

2017-01-01

Mental stress-induced ischemia approximately doubles the risk of cardiac events in patients with coronary artery disease, yet the mechanisms underlying changes in coronary blood flow in response to mental stress are poorly characterized. Neuronal nitric oxide synthase (nNOS) regulates basal coronary blood flow in healthy humans and mediates mental stress-induced vasodilation in the forearm. However, its possible role in mental stress-induced increases in coronary blood flow is unknown. We studied 11 patients (6 men and 5 women, mean age: 58 ± 14 yr) undergoing elective diagnostic cardiac catheterization and assessed the vasodilator response to mental stress elicited by the Stroop color-word test. Intracoronary substance P (20 pmol/min) and isosorbide dinitrate (1 mg) were used to assess endothelium-dependent and -independent vasodilation, respectively. Coronary blood flow was estimated using intracoronary Doppler recordings and quantitative coronary angiography to measure coronary artery diameter. Mental stress increased coronary flow by 34 ± 7.0% over the preceding baseline during saline infusion (P coronary artery diameter by 6.9 ± 3.7% (P = 0.02) and 0.5 ± 2.8% (P = 0.51) in the presence of S-methyl-l-thiocitrulline. The response to substance P did not predict the response to mental stress (r2 = −0.22, P = 0.83). nNOS mediates the human coronary vasodilator response to mental stress, predominantly through actions at the level of coronary resistance vessels. NEW & NOTEWORTHY Acute mental stress induces vasodilation of the coronary microvasculature. Here, we show that this response involves neuronal nitric oxide synthase in the human coronary circulation. Listen to this article’s corresponding podcast at http://ajpheart.podbean.com/e/nnos-and-coronary-flow-during-mental-stress/. PMID:28646032

The human coronary vasodilatory response to acute mental stress is mediated by neuronal nitric oxide synthase.

Science.gov (United States)

Khan, Sitara G; Melikian, Narbeh; Shabeeh, Husain; Cabaco, Ana R; Martin, Katherine; Khan, Faisal; O'Gallagher, Kevin; Chowienczyk, Philip J; Shah, Ajay M

2017-09-01

Mental stress-induced ischemia approximately doubles the risk of cardiac events in patients with coronary artery disease, yet the mechanisms underlying changes in coronary blood flow in response to mental stress are poorly characterized. Neuronal nitric oxide synthase (nNOS) regulates basal coronary blood flow in healthy humans and mediates mental stress-induced vasodilation in the forearm. However, its possible role in mental stress-induced increases in coronary blood flow is unknown. We studied 11 patients (6 men and 5 women, mean age: 58 ± 14 yr) undergoing elective diagnostic cardiac catheterization and assessed the vasodilator response to mental stress elicited by the Stroop color-word test. Intracoronary substance P (20 pmol/min) and isosorbide dinitrate (1 mg) were used to assess endothelium-dependent and -independent vasodilation, respectively. Coronary blood flow was estimated using intracoronary Doppler recordings and quantitative coronary angiography to measure coronary artery diameter. Mental stress increased coronary flow by 34 ± 7.0% over the preceding baseline during saline infusion ( P stress increased coronary artery diameter by 6.9 ± 3.7% ( P = 0.02) and 0.5 ± 2.8% ( P = 0.51) in the presence of S -methyl-l-thiocitrulline. The response to substance P did not predict the response to mental stress ( r 2 = -0.22, P = 0.83). nNOS mediates the human coronary vasodilator response to mental stress, predominantly through actions at the level of coronary resistance vessels. NEW & NOTEWORTHY Acute mental stress induces vasodilation of the coronary microvasculature. Here, we show that this response involves neuronal nitric oxide synthase in the human coronary circulation.Listen to this article's corresponding podcast at http://ajpheart.podbean.com/e/nnos-and-coronary-flow-during-mental-stress/. Copyright © 2017 the American Physiological Society.

CYP epoxygenase-derived H2O2 is involved in the endothelium-derived hyperpolarization (EDH) and relaxation of intrarenal arteries.

Science.gov (United States)

Muñoz, Mercedes; López-Oliva, Maria Elvira; Pinilla, Estéfano; Martínez, María Pilar; Sánchez, Ana; Rodríguez, Claudia; García-Sacristán, Albino; Hernández, Medardo; Rivera, Luis; Prieto, Dolores

2017-05-01

Reactive oxygen species (ROS) like hydrogen peroxide (H 2 O 2 ) are involved in the in endothelium-derived hyperpolarization (EDH)-type relaxant responses of coronary and mesenteric arterioles. The role of ROS in kidney vascular function has mainly been investigated in the context of harmful ROS generation associated to kidney disease. The present study was sought to investigate whether H 2 O 2 is involved in the endothelium-dependent relaxations of intrarenal arteries as well the possible endothelial sources of ROS generation involved in these responses. Under conditions of cyclooxygenase (COX) and nitric oxide (NO) synthase inhibition, acetylcholine (ACh) induced relaxations and stimulated H 2 O 2 release that were reduced by catalase and by the glutathione peroxidase (GPx) mimetic ebselen in rat renal interlobar arteries, suggesting the involvement of H 2 O 2 in the endothelium-dependent responses. ACh relaxations were also blunted by the CYP2C inhibitor sulfaphenazole and by the NADPH oxidase inhibitor apocynin. Acetylcholine stimulated both superoxide (O 2 •- ) and H 2 O 2 production that were reduced by sulfaphenazole and apocynin. Expression of the antioxidant enzyme CuZnSOD and of the H 2 O 2 reducing enzymes catalase and GPx-1 was found in both intrarenal arteries and renal cortex. On the other hand, exogenous H 2 O 2 relaxed renal arteries by decreasing vascular smooth muscle (VSM) intracellular calcium concentration [Ca 2+ ] i and markedly enhanced endothelial K Ca currents in freshly isolated renal endothelial cells. CYP2C11 and CYP2C23 epoxygenases were highly expressed in interlobar renal arteries and renal cortex, respectively, and were co-localized with eNOS in renal endothelial cells. These results demonstrate that H 2 O 2 is involved in the EDH-type relaxant responses of renal arteries and that CYP 2C epoxygenases are physiologically relevant endothelial sources of vasodilator H 2 O 2 in the kidney. Copyright © 2017 Elsevier Inc. All rights

Stress susceptibility as a determinant of endothelium-dependent vascular reactivity in rat mesenteric arteries.

NARCIS (Netherlands)

Riksen, N.P.; Ellenbroek, B.A.; Cools, A.R.; Siero, H.L.M.; Rongen, G.A.P.J.M.; Smits, B.W.; Russel, F.G.M.; Smits, P.

2003-01-01

In order to investigate the consequences of stress susceptibility on vascular function, the authors assessed the respective contributions of nitric oxide (NO), prostanoids, and endothelium-derived hyperpolarizing factor to the vascular tone in rats with a constitutionally determined high and low

Purple grape juice improves endothelial function and reduces the susceptibility of LDL cholesterol to oxidation in patients with coronary artery disease.

Science.gov (United States)

Stein, J H; Keevil, J G; Wiebe, D A; Aeschlimann, S; Folts, J D

1999-09-07

In vitro, the flavonoid components of red wine and purple grape juice are powerful antioxidants that induce endothelium-dependent vasodilation of vascular rings derived from rat aortas and human coronary arteries. Although improved endothelial function and inhibition of LDL oxidation may be potential mechanisms by which red wine and flavonoids reduce cardiovascular risk, the in vivo effects of grape products on endothelial function and LDL oxidation have not been investigated. This study assessed the effects of ingesting purple grape juice on endothelial function and LDL susceptibility to oxidation in patients with coronary artery disease (CAD). Fifteen adults with angiographically documented CAD ingested 7.7+/-1.2 mL. kg(-1). d(-1) of purple grape juice for 14 days. Flow-mediated vasodilation (FMD) was measured using high-resolution brachial artery ultrasonography. Susceptibility of LDL particles to oxidation was determined from the rate of conjugated diene formation after exposure to copper chloride. At baseline, FMD was impaired (2.2+/-2. 9%). After ingestion of grape juice, FMD increased to 6.4+/-4.7% (P=0.003). In a linear regression model that included age, artery diameter, lipid values, and use of lipid-lowering and antioxidant therapies, the effect of grape juice on FMD remained significant (mean change 4.2+/-4.4%, PFMD and reduces LDL susceptibility to oxidation in CAD patients. Improved endothelium-dependent vasodilation and prevention of LDL oxidation are potential mechanisms by which flavonoids in purple grape products may prevent cardiovascular events, independent of alcohol content.

Rho-kinase inhibitor and nicotinamide adenine dinucleotide phosphate oxidase inhibitor prevent impairment of endothelium-dependent cerebral vasodilation by acute cigarette smoking in rats.

Science.gov (United States)

Iida, Hiroki; Iida, Mami; Takenaka, Motoyasu; Fukuoka, Naokazu; Dohi, Shuji

2008-06-01

We previously reported that acute cigarette smoking can cause a dysfunction of endothelium-dependent vasodilation in cerebral vessels, and that blocking the angiotensin II (Ang II) type 1 (AT1) receptor with valsartan prevented this impairment. Our aim was to investigate the effects of a Rho-kinase inhibitor (fasudil) and a Nicotinamide Adenine Dinucleotide PHosphate (NADPH) oxidase inhibitor (apocynin) on smoking-induced endothelial dysfunction in cerebral arterioles. In Sprague-Dawley rats, we used a closed cranial window preparation to measure changes in pial vessel diameters following topical acetylcholine (ACh) before smoking. After one-minute smoking, we again examined the arteriolar responses to ACh. Finally, after intravenous fasudil or apocynin pre-treatment we re-examined the vasodilator responses to topical ACh (before and after cigarette smoking). Under control conditions, cerebral arterioles were dose-dependently dilated by topical ACh (10(-6) M and 10(-5) M). One hour after a one-minute smoking (1 mg-nicotine cigarette), 10(-5) M ACh constricted cerebral arterioles. However, one hour after a one-minute smoking, 10(-5) M ACh dilated cerebral pial arteries both in the fasudil pre-treatment and the apocynin pre-treatment groups, responses that were significantly different from those obtained without fasudil or apocynin pre-treatment. Thus, inhibition of Rho-kinase and NADPH oxidase activities may prevent the above smoking-induced impairment of endothelium-dependent vasodilation.

Surface Topographical Modification of Coronary Stent: A Review

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Tan, C. H.; Muhamad, N.; Abdullah, M. M. A. B.

2017-06-01

Driven by the urge of mediating the inflammatory response from coronary stent implant to improve patency rates of the current coronary stent, concern has been focusing on reducing the risk of in-stent restenosis and thrombosis for long-term safety. Surface modification approach has been found to carry great potential due to the surface is the vital parts that act as a buffer layer between the biomaterial and the organic material like blood and vessel tissues. Nevertheless, manipulating cell response in situ using physical patterning is very complex as the exact mechanism were yet elucidated. Thus, the aim of this review is to summarise the recent efforts on modifying the surface topography of coronary stent at the micro- and nanometer scale with the purpose of inducing rapid in situ endothelialization to regenerate a healthy endothelium layer on biomaterial surface. In particular, a discussion on the surface patterns that have been investigated on cell selective behaviour together with the methods used to generate them are presented. Furthermore, the probable future work involving the surface modification of coronary stent were indicated.

EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA); Scientific Opinion on the substantiation of a health claim related to cocoa flavanols and maintenance of normal endothelium-dependent vasodilation pursuant to Article 13(5) of Regulation (EC) No 1924/2006

DEFF Research Database (Denmark)

Tetens, Inge

Following an application from Barry Callebaut Belgium nv, submitted pursuant to Article 13(5) of Regulation (EC) No 1924/2006 via the Competent Authority of Belgium, the Panel on Dietetic Products, Nutrition and Allergies (NDA) was asked to deliver an opinion on the scientific substantiation...... of a health claim related to cocoa flavanols and maintenance of normal endothelium-dependent vasodilation. Cocoa flavanols are sufficiently characterised. The claimed effect is “help maintain endothelium-dependent vasodilation which contributes to healthy blood flow”. The target population proposed...... by the applicant is the general healthy adult population. The Panel considers that maintenance of normal endothelium-dependent vasodilation is a beneficial physiological effect. In weighing the evidence, the Panel took into account that cocoa flavanols consumed for 12 weeks have been shown to increase fasting ED...

The study of the functional state of the endothelium via a complex of markers with reactive hyperemia

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Berezhniy V.

2016-03-01

Full Text Available Diagnosis of endothelial dysfunction is a key point in the prevention and treatment of cardiovascular diseases. In scientific research the study of the state of the endothelium used test with reactive hyperemia of brachial artery wich present as the value of endothelium dependent and independent artery dilatation. However, the disadvantage of this marker is ignoring the size of arteries, well know that small arteries has a greater degree of dilation more than big arterias, this fact making difficult to compare results between different patients. The aim of our study was to examine the state of endothelium using a complex of markers, compare them informative in children with JRA who are at risk for the development of endothelial dysfunction. Materials and Methods. The study was included 40 children with juvenile rheumatoid arthritis who were treated at the department of children's cardiorheumatology Kyiv City Children's Hospital #1 and Kiev Regional Hospital m. Boyarka. Results. The study found a development of endothelial dysfunction changes in endothelium dependent vasodilation, reactive hyperemia and coefficient of vasodilation. Simultaneous marked change of endothelium vasodilation of the brachial artery and coefficient of vasodilatation. There were no pathological changes in endothelial shear stress in patients compared with healthy children. Conclusions. Evaluate the state of the endothelium is necessary with the help of a set of indicators (RH, EDVD, VC that will help to avoid diagnostic mistakes during the test with the reactive hyperemia.

Effect of prolonged incubation with copper on endothelium-dependent relaxation in rat isolated aorta

Science.gov (United States)

Chiarugi, Alberto; Pitari, Giovanni Mario; Costa, Rosa; Ferrante, Margherita; Villari, Loredana; Amico-Roxas, Matilde; Godfraind, Théophile; Bianchi, Alfredo; Salomone, Salvatore

2002-01-01

We investigated the effects of prolonged exposure to copper (Cu2+) on vascular functioning of isolated rat aorta. Aortic rings were exposed to CuSO4 (3–24 h) in Dulbecco's modified Eagle medium with or without 10% foetal bovine serum (FBS) and then challenged with vasoconstrictors or vasodilators in the absence of Cu2+. Exposure to 2 μM Cu2+ in the absence of FBS did not modify the response to phenylephrine (PE) or acetylcholine (ACh) in aortic rings incubated for 24 h. Identical exposure in the presence of FBS increased the contractile response to 1 μM PE by 30% (P<0.05) and impaired the relaxant response to 3 μM ACh or 1 μM A23187 (ACh, from 65.7±7.1 to 6.2±1.1%, n=8; A23187, from 74.6±8.2 to 12.0±0.8%, n=6; P<0.01 for both). Cu2+ exposure did not affect the relaxant response to NO-donors. Impairment of vasorelaxation appeared 3 h after incubation with 2 μM Cu2+ and required 12 h to attain a steady state. Vasorelaxation to ACh was partially restored by 1 mM tiron (intracellular scavenger of superoxide ions; maximum relaxation 34.2±6.4%, n=10, P<0.01 vs Cu2+ alone), whereas catalase, superoxide dismutase or cycloheximide were ineffective. Twenty-four hour-exposure to 2 μM Cu2+ did not affect endothelium integrity or eNOS expression, and increased the Cu content in arterial rings from 6.8±1.1 to 18.9±2.9 ng mg−1 wet weight, n=8; P<0.01. Our results show that, in the presence of FBS, prolonged exposure to submicromolar concentrations of Cu2+ impaired endothelium-dependent vasorelaxation in aortic rings, probably through an intracellular generation of superoxide ions. PMID:12163352

Hypertrophy of cultured bovine aortic endothelium following irradiation

International Nuclear Information System (INIS)

Rosen, E.M.; Vinter, D.W.; Goldberg, I.D.

1989-01-01

The vascular endothelium is a vital multifunctional tissue which covers the entire luminal surface of the circulatory system. Loss of continuity of the endothelial lining normally results in cell migration and proliferation to make up for cell loss and to ensure that exposure of the thrombogenic subendothelium to platelets and clotting factors is minimized. We showed that ionizing radiation (400-3000 cGy) causes dose-dependent cell loss from confluent monolayer cultures of bovine aortic endothelium, which cannot immediately be compensated by cell proliferation. Within 24 h, the remaining attached cells undergo substantial somatic hypertrophy (evidenced by increased protein content, cell volume, and attachment area) but remain diploid. If cell loss is not excessive, monolayer continuity is restored within several days. Although reduced protein degradation may contribute, most of the protein accumulation is due to synthesis of new protein. Unlike endothelium, irradiation of smooth muscle cultures causes neither cell loss nor increased protein synthesis. Hypertrophy of irradiated endothelial cells appears to be a consequence of a proliferative stimulus (cell loss) in a population of cells which is unable to divide. It can be modulated by replating irradiated cells at different densities. We suggest that endothelial hypertrophy is an early vascular homeostatic response before clonal proliferation of surviving cells or repopulation by cells from outside of the irradiated field can compensate for cell loss

Vitamin C Deficiency Reduces Muscarinic Receptor Coronary Artery Vasoconstriction and Plasma Tetrahydrobiopterin Concentration in Guinea Pigs

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Gry Freja Skovsted

2017-07-01

Full Text Available Vitamin C (vitC deficiency is associated with increased cardiovascular disease risk, but its specific interplay with arteriolar function is unclear. This study investigates the effect of vitC deficiency in guinea pigs on plasma biopterin status and the vasomotor responses in coronary arteries exposed to vasoconstrictor/-dilator agents. Dunkin Hartley female guinea pigs (n = 32 were randomized to high (1500 mg/kg diet or low (0 to 50 mg/kg diet vitC for 10–12 weeks. At euthanasia, coronary artery segments were dissected and mounted in a wire-myograph. Vasomotor responses to potassium, carbachol, sodium nitroprusside (SNP, U46619, sarafotoxin 6c (S6c and endothelin-1 (ET-1 were recorded. Plasma vitC and tetrahydrobiopterin were measured by HPLC. Plasma vitC status reflected the diets with deficient animals displaying reduced tetrahydrobiopterin. Vasoconstrictor responses to carbachol were significantly decreased in vitC deficient coronary arteries independent of their general vasoconstrictor/vasodilator capacity (p < 0.001. Moreover, in vitC deficient animals, carbachol-induced vasodilator responses correlated with coronary artery diameter (p < 0.001. Inhibition of cyclooxygenases with indomethacin increased carbachol-induced vasoconstriction, suggesting an augmented carbachol-induced release of vasodilator prostanoids. Atropine abolished carbachol-induced vasomotion, supporting a specific muscarinic receptor effect. Arterial responses to SNP, potassium, S6c, U46619 and ET-1 were unaffected by vitC status. The study shows that vitC deficiency decreases tetrahydrobiopterin concentrations and muscarinic receptor mediated contraction in coronary arteries. This attenuated vasoconstrictor response may be linked to altered production of vasoactive arachidonic acid metabolites and reduced muscarinic receptor expression/signaling.

Autonomic control of vasomotion in the porcine coronary circulation during treadmill exercise: evidence for feed-forward beta-adrenergic control

NARCIS (Netherlands)

D.J.G.M. Duncker (Dirk); R. Stubenitsky (René); P.D. Verdouw (Pieter)

1998-01-01

textabstractTo date, no studies have investigated coronary vasomotor control of myocardial O2 delivery (MDO2) and its modulation by the autonomic nervous system in the porcine heart during treadmill exercise. We studied 8 chronically instrumented swine under resting

Swimming training prevents coronary endothelial dysfunction in ovariectomized spontaneously hypertensive rats

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E.R.G. Claudio

Full Text Available Estrogen deficiency and hypertension are considered major risk factors for the development of coronary heart disease. On the other hand, exercise training is considered an effective form to prevent and treat cardiovascular diseases. However, the effects of swimming training (SW on coronary vascular reactivity in female ovariectomized hypertensive rats are not known. We aimed to evaluate the effects of SW on endothelium-dependent coronary vasodilation in ovariectomized hypertensive rats. Three-month old spontaneously hypertensive rats (SHR, n=50 were divided into four groups: sham (SH, sham plus swimming training (SSW, ovariectomized (OVX, and ovariectomized plus swimming training (OSW. The SW protocol (5 times/week, 60 min/day was conducted for 8 weeks. The vasodilatory response was measured in isolated hearts in the absence and presence of a nitric oxide synthase inhibitor (L-NAME, 100 µM. Cardiac oxidative stress was evaluated in situ by dihydroethidium fluorescence, while the expression of antioxidant enzymes (SOD-2 and catalase and their activities were assessed by western blotting and spectrophotometry, respectively. Vasodilation in SHR was significantly reduced by OVX, even in the presence of L-NAME, in conjunction with an increased oxidative stress. These effects were prevented by SW, and were associated with a decrease in oxidative stress. Superoxide dismutase 2 (SOD-2 and catalase expression increased only in the OSW group. However, no significant difference was found in the activity of these enzymes. In conclusion, SW prevented the endothelial dysfunction in the coronary bed of ovariectomized SHR associated with an increase in the expression of antioxidant enzymes, and therefore may prevent coronary heart disease in hypertensive postmenopausal women.

Excess L-arginine restores endothelium-dependent relaxation impaired by monocrotaline pyrrole

International Nuclear Information System (INIS)

Cheng Wei; Oike, Masahiro; Hirakawa, Masakazu; Ohnaka, Keizo; Koyama, Tetsuya; Ito, Yushi

2005-01-01

The pyrrolizidine alkaloid plant toxin monocrotaline pyrrole (MCTP) causes pulmonary hypertension in experimental animals. The present study aimed to examine the effects of MCTP on the endothelium-dependent relaxation. We constructed an in vitro disease model of pulmonary hypertension by overlaying MCTP-treated bovine pulmonary artery endothelial cells (CPAEs) onto pulmonary artery smooth muscle cell-embedded collagen gel lattice. Acetylcholine (Ach) induced a relaxation of the control CPAEs-overlaid gels that were pre-contracted with noradrenaline, and the relaxation was inhibited by L-NAME, an inhibitor of NO synthase (NOS). In contrast, when MCTP-treated CPAEs were overlaid, the pre-contracted gels did not show a relaxation in response to Ach in the presence of 0.5 mM L-arginine. Expression of endothelial NOS protein, Ach-induced Ca 2+ transients and cellular uptake of L-[ 3 H]arginine were significantly smaller in MCTP-treated CPAEs than in control cells, indicating that these changes were responsible for the impaired NO production in MCTP-treated CPAEs. Since cellular uptake of L-[ 3 H]arginine linearly increased according to its extracellular concentration, we hypothesized that the excess concentration of extracellular L-arginine might restore NO production in MCTP-treated CPAEs. As expected, in the presence of 10 mM L-arginine, Ach showed a relaxation of the MCTP-treated CPAEs-overlaid gels. These results indicate that the impaired NO production in damaged endothelial cells can be reversed by supplying excess L-arginine

Cigarette smoke extract increases albumin flux across pulmonary endothelium in vitro

International Nuclear Information System (INIS)

Holden, W.E.; Maier, J.M.; Malinow, M.R.

1989-01-01

Cigarette smoking causes lung inflammation, and a characteristic of inflammation is an increase in vascular permeability. To determine if cigarette smoke could alter endothelial permeability, we studied flux of radiolabeled albumin across monolayers of porcine pulmonary artery endothelium grown in culture on microporous membranes. Extracts (in either dimethylsulfoxide or phosphate-buffered saline) of cigarette smoke in a range estimate of concentrations simulating cigarette smoke exposure to the lungs in vivo caused a dose-dependent increase in albumin flux that was dependent on extracellular divalent cations and associated with polymerization of cellular actin. The effect was reversible, independent of the surface of endothelial cells exposed (either luminal or abluminal), and due primarily to components of the vapor phase of smoke. The effects occurred without evidence of cell damage, but subtle morphological changes were produced by exposure to the smoke extracts. These findings suggest that cigarette smoke can alter permeability of the lung endothelium through effects on cytoskeletal elements

Endothelium-dependent hyperpolarization-related relaxations diminish with age in murine saphenous arteries of both sexes

DEFF Research Database (Denmark)

Chennupati, R.; Lamers, W. H.; Koehler, S. E.

2013-01-01

nitroprusside and to ACh in the absence of pharmacological inhibitors (indomethacin and L-NAME), were similar in all age groups and sexes, but those mediated by endothelium-derived NO were slightly but significantly increased in 64-week-old male mice. In the presence of inhibitors, 12-week-old animals showed...... pronounced ACh-induced relaxation, which was significantly reduced in 34- and 64-week-old mice of both sexes. The EDH-related component of ACh-induced relaxations was abolished by TRAM-34 (K(Ca)3.1 blocker) or UCL 1684 (K(Ca)2.3 blocker). Although the maximal relaxation induced by NS309 (K-Ca activator......) was not affected by aging, the sensitivity for NS309 significantly decreased with aging. The presence of SKA-31 (K-Ca modulator) potentiated relaxations induced by ACh in arteries of 12-week-old but not older mice. CONCLUSION AND IMPLICATIONS In a small muscular artery of mice of either sex, total endothelium...

Threshold-dependent variability of coronary artery calcification measurements - implications for contrast-enhanced multi-detector row-computed tomography

International Nuclear Information System (INIS)

Moselewski, Fabian; Ferencik, Maros; Achenbach, Stephan; Abbara, Suhny; Cury, Ricardo C.; Booth, Sarah L.; Jang, Ik-Kyung; Brady, Thomas J.; Hoffmann, Udo

2006-01-01

Introduction: The present study investigated the threshold-dependent variability of coronary artery calcification (CAC) measurements and the potential to quantify CAC in contrast-enhanced multi-detector row-computed tomography (MDCT). Methods: We compared the mean CT attenuation of CAC to luminal contrast enhancement of the coronary arteries in 30 patients (n = 30) undergoing standard coronary contrast-enhanced spiral MDCT. The modified Agatston score [AS], calcified plaque volume [CV], and mineral mass [MM]) at four different thresholds (130, 200, 300, and 400 HU) were measured in 50 patients who underwent non-contrast-enhanced MDCT. Results: Mean CT attenuation of CAC was similar to the attenuation of the contrast-enhanced coronary lumen (CAC 297.1 ± 68.7 HU versus 295 ± 65 HU (p < 0.0001), respectively). Above a threshold of 300 HU CAC measurements significantly varied to standard measurements obtained at a threshold of 130 HU (p < 0.0001). The threshold-dependent variation of MM measurements was significantly smaller than for AS and CV (130 HU versus 400 HU: 63, 75, and 81, respectively; p < 0.001). These differences resulted in a change of age and gender based percentile category for AS in 78% of subjects. Discussion: We demonstrated that CAC measurements are threshold dependent with MM measurements having significantly less variation than AS or CV. Due to the similarity of mean CT attenuation of CAC and the contrast-enhanced coronary lumen accurate quantification of CAC may be difficult in standard coronary contrast-enhanced spiral MDCT

Threshold-dependent variability of coronary artery calcification measurements - implications for contrast-enhanced multi-detector row-computed tomography

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Moselewski, Fabian [Division of Cardiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA (United States); Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA (United States); Ferencik, Maros [Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA (United States); Achenbach, Stephan [Division of Cardiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA (United States); Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA (United States); Department of Internal Medicine II (Cardiology), University of Erlangen (Germany); Abbara, Suhny [Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA (United States); Cury, Ricardo C. [Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA (United States); Booth, Sarah L. [Jean Mayer USDA Human Nutrition Research Center on Aging, 711 Washington St., Boston, MA 02114 (United States); Jang, Ik-Kyung [Division of Cardiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA (United States); Brady, Thomas J. [Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA (United States); Hoffmann, Udo [Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA (United States)]. E-mail: uhoffman@partners.org

2006-03-15

Introduction: The present study investigated the threshold-dependent variability of coronary artery calcification (CAC) measurements and the potential to quantify CAC in contrast-enhanced multi-detector row-computed tomography (MDCT). Methods: We compared the mean CT attenuation of CAC to luminal contrast enhancement of the coronary arteries in 30 patients (n = 30) undergoing standard coronary contrast-enhanced spiral MDCT. The modified Agatston score [AS], calcified plaque volume [CV], and mineral mass [MM] at four different thresholds (130, 200, 300, and 400 HU) were measured in 50 patients who underwent non-contrast-enhanced MDCT. Results: Mean CT attenuation of CAC was similar to the attenuation of the contrast-enhanced coronary lumen (CAC 297.1 {+-} 68.7 HU versus 295 {+-} 65 HU (p < 0.0001), respectively). Above a threshold of 300 HU CAC measurements significantly varied to standard measurements obtained at a threshold of 130 HU (p < 0.0001). The threshold-dependent variation of MM measurements was significantly smaller than for AS and CV (130 HU versus 400 HU: 63, 75, and 81, respectively; p < 0.001). These differences resulted in a change of age and gender based percentile category for AS in 78% of subjects. Discussion: We demonstrated that CAC measurements are threshold dependent with MM measurements having significantly less variation than AS or CV. Due to the similarity of mean CT attenuation of CAC and the contrast-enhanced coronary lumen accurate quantification of CAC may be difficult in standard coronary contrast-enhanced spiral MDCT.

Semi-quantitative assessments of dextran toxicity on corneal endothelium: conceptual design of a predictive algorithm.

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Filev, Filip; Oezcan, Ceprail; Feuerstacke, Jana; Linke, Stephan J; Wulff, Birgit; Hellwinkel, Olaf J C

2017-03-01

Dextran is added to corneal culture medium for at least 8 h prior to transplantation to ensure that the cornea is osmotically dehydrated. It is presumed that dextran has a certain toxic effect on corneal endothelium but the degree and the kinetics of this effect have not been quantified so far. We consider that such data regarding the toxicity of dextran on the corneal endothelium could have an impact on scheduling and logistics of corneal preparation in eye banking. In retrospective statistic analyses, we compared the progress of corneal endothelium (endothelium cell loss per day) of 1334 organ-cultured corneal explants in media with and without dextran. Also, the influence of donor-age, sex and cause of death on the observed dextran-mediated effect on endothelial cell counts was studied. Corneas cultured in dextran-free medium showed a mean endothelium cell count decrease of 0.7% per day. Dextran supplementation led to a mean endothelium cell loss of 2.01% per day; this reflects an increase by the factor of 2.9. The toxic impact of dextran was found to be time dependent; while the prevailing part of the effect was observed within the first 24 h after dextran-addition. Donor age, sex and cause of death did not seem to have an influence on the dextran-mediated toxicity. Based on these findings, we could design an algorithm which approximately describes the kinetics of dextran-toxicity. We reproduced the previously reported toxic effect of dextran on the corneal endothelium in vitro. Additionally, this is the first work that provides an algorithmic instrument for the semi-quantitative calculation of the putative endothelium cell count decrease in dextran containing medium for a given incubation time and could thus influence the time management and planning of corneal transplantations.

Nitric oxide, cholesterol oxides and endothelium-dependent vasodilation in plasma of patients with essential hypertension

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P. Moriel

2002-11-01

Full Text Available The objective of the present study was to identify disturbances of nitric oxide radical (·NO metabolism and the formation of cholesterol oxidation products in human essential hypertension. The concentrations of·NO derivatives (nitrite, nitrate, S-nitrosothiols and nitrotyrosine, water and lipid-soluble antioxidants and cholesterol oxides were measured in plasma of 11 patients with mild essential hypertension (H: 57.8 ± 9.7 years; blood pressure, 148.3 ± 24.8/90.8 ± 10.2 mmHg and in 11 healthy subjects (N: 48.4 ± 7.0 years; blood pressure, 119.4 ± 9.4/75.0 ± 8.0 mmHg.Nitrite, nitrate and S-nitrosothiols were measured by chemiluminescence and nitrotyrosine was determined by ELISA. Antioxidants were determined by reverse-phase HPLC and cholesterol oxides by gas chromatography. Hypertensive patients had reduced endothelium-dependent vasodilation in response to reactive hyperemia (H: 9.3 and N: 15.1% increase of diameter 90 s after hyperemia, and lower levels of ascorbate (H: 29.2 ± 26.0, N: 54.2 ± 24.9 µM, urate (H: 108.5 ± 18.9, N: 156.4 ± 26.3 µM, ß-carotene (H: 1.1 ± 0.8, N: 2.5 ± 1.2 nmol/mg cholesterol, and lycopene (H: 0.4 ± 0.2, N: 0.7 ± 0.2 nmol/mg cholesterol, in plasma, compared to normotensive subjects. The content of 7-ketocholesterol, 5alpha-cholestane-3ß,5,6ß-triol and 5,6alpha-epoxy-5alpha-cholestan-3alpha-ol in LDL, and the concentration of endothelin-1 (H: 0.9 ± 0.2, N: 0.7 ± 0.1 ng/ml in plasma were increased in hypertensive patients. No differences were found for ·NO derivatives between groups. These data suggest that an increase in cholesterol oxidation is associated with endothelium dysfunction in essential hypertension and oxidative stress, although ·NO metabolite levels in plasma are not modified in the presence of elevated cholesterol oxides.

Endothelium-dependent vasorelaxant effect of procyanidin B2 on human internal mammary artery.

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Novakovic, Aleksandra; Marinko, Marija; Jankovic, Goran; Stojanovic, Ivan; Milojevic, Predrag; Nenezic, Dragoslav; Kanjuh, Vladimir; Yang, Qin; He, Guo-Wei

2017-07-15

The aim of the present study was to investigate and characterize vasorelaxant effect of procyanidin B2 on human internal mammary artery (HIMA) as one of the mechanisms of its protective effect against vascular risk. Procyanidin B2 induced strong concentration-dependent relaxation of HIMA rings pre-contracted by phenylephrine. Pretreatment with L-NAME, a NO synthase inhibitor, hydroxocobalamin, a NO scavenger, and ODQ, an inhibitor of soluble guanylate cyclase, significantly inhibited procyanidin B2-induced relaxation of HIMA, while indomethacin, a cyclooxygenase inhibitor, considerably reduced effects of low concentrations. Among K + channel blockers, iberiotoxin, a selective blocker of large conductance Ca 2+ -activated K + channels (BK Ca ), abolished procyanidin B2-induced relaxation, glibenclamide, a selective ATP-sensitive K + (K ATP ) channels blocker, induced partial inhibition, while 4-aminopyridine, a blocker of voltage-gated K + (K V ) channels, and TRAM-34, an inhibitor of intermediate-conductance Ca 2+ -activated K + (IK Ca ) channels, slightly reduced maximal relaxation of HIMA. Further, procyanidin B2 relaxed contraction induced by phenylephrine in Ca 2+ -free Krebs solution, but had no effect on contraction induced by caffeine. Finally, thapsigargin, a sarcoplasmic reticulum Ca 2+ -ATPase inhibitor, significantly reduced relaxation of HIMA produced by procyanidin B2. These results demonstrate that procyanidin B2 produces endothelium-dependent relaxation of HIMA pre-contracted by phenylephrine. This effect is primarily the result of an increased NO synthesis and secretion by endothelial cells and partially of prostacyclin, although it involves activation of BK Ca and K ATP , as well as K V and IK Ca channels in high concentrations of procyanidin B2. Copyright © 2017 Elsevier B.V. All rights reserved.

Vasomotor Regulation of Coronary Microcirculation by Oxidative Stress: Role of Arginase

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Lih eKuo

2013-08-01

Full Text Available Overproduction of reactive oxygen species, i.e., oxidative stress, is associated with the activation of redox signaling pathways linking to inflammatory insults and cardiovascular diseases by impairing endothelial function and consequently blood flow dysregulation due to microvascular dysfunction. This review focuses on the regulation of vasomotor function in the coronary microcirculation by endothelial nitric oxide (NO during oxidative stress and inflammation related to the activation of L-arginine consuming enzyme arginase. Superoxide produced in the vascular wall compromises vasomotor function by not only scavenging endothelium-derived NO but also inhibiting prostacyclin synthesis due to formation of peroxynitrite. The upregulation of arginase contributes to the deficiency of endothelial NO and microvascular dysfunction in various vascular diseases by initiating or following oxidative stress and inflammation. Hydrogen peroxide, a diffusible and stable oxidizing agent, exerts vasodilator function and plays important roles in the physiological regulation of coronary blood flow. In occlusive coronary ischemia, the release of hydrogen peroxide from the microvasculature helps to restore vasomotor function of coronary collateral microvessels with exercise training. However, excessive production and prolonged exposure of microvessels to hydrogen peroxide impairs NO-mediated endothelial function by reducing L-arginine availability through hydroxyl radical-dependent upregulation of arginase. The redox signaling can be a double-edged sword in the microcirculation, which helps tissue survival in one way by improving vasomotor regulation and elicits oxidative stress and tissue injury in the other way by causing vascular dysfunction. The impact of vascular arginase on the development of vasomotor dysfunction associated with angiotensin II receptor activation, hypertension, ischemia-reperfusion, hypercholesterolemia and inflammatory insults is discussed.

Modified method for intravital-fluorescent microscopy for on-line measurement of vasomotion in cutaneous microcirculation of mice in vivo

International Nuclear Information System (INIS)

Traikov, L.; Jia, F.; Ushiyama, A.; Masuda, H.; Ohkubo, C.

2004-01-01

The purpose of this study was establishing of the suitable method for long term investigations of changes of the blood vessel diameter up to 60 min continuous measurements with the main aim to be detected possible changes in low frequency component of vasomotion at cutaneous microcirculation of mice in vivo without using anesthetized animals. For investigation of micro-circulatory changes of blood vessel diameter, it is necessary to be used as high as possible quality video images with high resolution (1591x1061 pixels) - at this time the best method for this purpose is intravital microscopy, with high magnification and high resolution this method allows to be observed blood vessels from 5 to 100 μm - and also to be determined blood vessel wall and surrounded blood vessel cells. In this investigation BALB/c mice were used, and a Dorsal Skin-fold Chamber (DSC), were surgically implanted 4 days before the experiment. Intravital video-microscopy measurements of vasomotion in vivo were realized by 3CCD-camera, SONY Inc. and Nikon Inc. microscopy system. Fluorescence signal from the blood vessel, were enhanced by using DVS-3000 system (Hamamatsu Inc.) Vasomotion or temporal changes of the blood vessel diameter was measured by High-speed Digital Machine Vision System CV-2100 (KEYENCE Inc.), using an edge-gap detection algorithm (with a sampling time 389 ms), for on-line calculating the outer diameter of the blood vessels by means of fluorescence-image visualization (with precision 0.5 μm), after caudal vein injection of (from 50h150 μl per 25g animal) Fluorescein Isothiocyanate (FITC)-labeled Dextrans from 60-250 kDa concentration 2.5% in PBS solution pH=7.5. First part of this study was set up the intensity of the fluorescence using different concentrations and molecular weight Dextrans for visualization of the blood plasma with enough high intensity and as low as possible effects on the blood viscosity. Set up of the edge finding algorithm from off-line calculations

Activation of a cGMP-sensitive calcium-dependent chloride channel may cause transition from calcium waves to whole-cell oscillations in smooth muscle cells

DEFF Research Database (Denmark)

Jacobsen, Jens Christian; Aalkjær, Christian; Nilsson, Holger

2007-01-01

waves sweeping through the cytoplasm when the SR is stimulated to release calcium. A rise in cyclic guanosine monophosphate (cGMP) leads to the experimentally observed transition from waves to whole-cell calcium oscillations. At the same time membrane potential starts to oscillate and the frequency...... approximately doubles. In this transition, the simulated results point to a key role for a recently discovered cGMP-sensitive calcium-dependent chloride channel. This channel depolarizes the membrane in response to calcium released from the SR. In turn, depolarization causes uniform opening of L-type calcium...... onset of oscillations in membrane potential within the individual cell may underlie sudden intercellular synchronization and the appearance of vasomotion. Key words: Vasomotion, Chloride channel, cGMP, Mathematical model, Calcium waves....

Depletion of NADP(H) due to CD38 activation triggers endothelial dysfunction in the postischemic heart.

Science.gov (United States)

Reyes, Levy A; Boslett, James; Varadharaj, Saradhadevi; De Pascali, Francesco; Hemann, Craig; Druhan, Lawrence J; Ambrosio, Giuseppe; El-Mahdy, Mohamed; Zweier, Jay L

2015-09-15

In the postischemic heart, coronary vasodilation is impaired due to loss of endothelial nitric oxide synthase (eNOS) function. Although the eNOS cofactor tetrahydrobiopterin (BH4) is depleted, its repletion only partially restores eNOS-mediated coronary vasodilation, indicating that other critical factors trigger endothelial dysfunction. Therefore, studies were performed to characterize the unidentified factor(s) that trigger endothelial dysfunction in the postischemic heart. We observed that depletion of the eNOS substrate NADPH occurs in the postischemic heart with near total depletion from the endothelium, triggering impaired eNOS function and limiting BH4 rescue through NADPH-dependent salvage pathways. In isolated rat hearts subjected to 30 min of ischemia and reperfusion (I/R), depletion of the NADP(H) pool occurred and was most marked in the endothelium, with >85% depletion. Repletion of NADPH after I/R increased NOS-dependent coronary flow well above that with BH4 alone. With combined NADPH and BH4 repletion, full restoration of NOS-dependent coronary flow occurred. Profound endothelial NADPH depletion was identified to be due to marked activation of the NAD(P)ase-activity of CD38 and could be prevented by inhibition or specific knockdown of this protein. Depletion of the NADPH precursor, NADP(+), coincided with formation of 2'-phospho-ADP ribose, a CD38-derived signaling molecule. Inhibition of CD38 prevented NADP(H) depletion and preserved endothelium-dependent relaxation and NO generation with increased recovery of contractile function and decreased infarction in the postischemic heart. Thus, CD38 activation is an important cause of postischemic endothelial dysfunction and presents a novel therapeutic target for prevention of this dysfunction in unstable coronary syndromes.

The Deletion of Endothelial Sodium Channel α (αENaC Impairs Endothelium-Dependent Vasodilation and Endothelial Barrier Integrity in Endotoxemia in Vivo

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Magdalena Sternak

2018-04-01

Full Text Available The role of epithelial sodium channel (ENaC activity in the regulation of endothelial function is not clear. Here, we analyze the role of ENaC in the regulation of endothelium-dependent vasodilation and endothelial permeability in vivo in mice with conditional αENaC subunit gene inactivation in the endothelium (endo-αENaCKO mice using unique MRI-based analysis of acetylcholine-, flow-mediated dilation and vascular permeability. Mice were challenged or not with lipopolysaccharide (LPS, from Salmonella typhosa, 10 mg/kg, i.p.. In addition, changes in vascular permeability in ex vivo organs were analyzed by Evans Blue assay, while changes in vascular permeability in perfused mesenteric artery were determined by a FITC-dextran-based assay. In basal conditions, Ach-induced response was completely lost, flow-induced vasodilation was inhibited approximately by half but endothelial permeability was not changed in endo-αENaCKO vs. control mice. In LPS-treated mice, both Ach- and flow-induced vasodilation was more severely impaired in endo-αENaCKO vs. control mice. There was also a dramatic increase in permeability in lungs, brain and isolated vessels as evidenced by in vivo and ex vivo analysis in endotoxemic endo-αENaCKO vs. control mice. The impaired endothelial function in endotoxemia in endo-αENaCKO was associated with a decrease of lectin and CD31 endothelial staining in the lung as compared with control mice. In conclusion, the activity of endothelial ENaC in vivo contributes to endothelial-dependent vasodilation in the physiological conditions and the preservation of endothelial barrier integrity in endotoxemia.

Toxicity of methods of implant material sterilization on corneal endothelium

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Singh, G.; Boehnke, Mv.; von Domarus, D.; Draeger, J.

1985-11-01

The toxicity of different procedures utilized for the sterilization of intraocular implant material was assessed on the endothelium of organ-cultured porcine corneas. Polymethylmethacrylate lenses sterilized by treatment with sodium hydroxide (NaOH), ethylene oxide, formaldehyde, and gamma radiation were added to a culture medium containing normal porcine corneas. Considering the viability of endothelial cells, appearance of intracellular degenerative vacuoles, and denudation of corneal Descemet's membrane as criterion for the evaluation of toxicity of different methods of sterilization, the NaOH-treated lenses were found to be the least toxic to porcine corneal endothelium. Phase-contrast microscopy and vital staining of the endothelium permitted direct viewing of the endothelium aiding in the assessment of toxicity.

The Role of the Endothelium in HPS Pathogenesis and Potential Therapeutic Approaches

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Irina Gavrilovskaya

2012-01-01

Full Text Available American hantaviruses cause a highly lethal acute pulmonary edema termed hantavirus pulmonary syndrome (HPS. Hantaviruses nonlytically infect endothelial cells and cause dramatic changes in barrier functions of the endothelium without disrupting the endothelium. Instead hantaviruses cause changes in the function of infected endothelial cells that normally regulate fluid barrier functions of capillaries. The endothelium of arteries, veins, and lymphatic vessels is unique and central to the function of vast pulmonary capillary beds, which regulate pulmonary fluid accumulation. The endothelium maintains vascular barrier functions through a complex series of redundant receptors and signaling pathways that serve to both permit fluid and immune cell efflux into tissues and restrict tissue edema. Infection of the endothelium provides several mechanisms for hantaviruses to alter capillary permeability but also defines potential therapeutic targets for regulating acute pulmonary edema and HPS disease. Here we discuss interactions of HPS causing hantaviruses with the endothelium, potential endothelial cell-directed permeability mechanisms, and therapeutic targeting of the endothelium as a means of reducing the severity of HPS disease.

Glucose-coated gold nanoparticles transfer across human brain endothelium and enter astrocytes in vitro.

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Radka Gromnicova

Full Text Available The blood-brain barrier prevents the entry of many therapeutic agents into the brain. Various nanocarriers have been developed to help agents to cross this barrier, but they all have limitations, with regard to tissue-selectivity and their ability to cross the endothelium. This study investigated the potential for 4 nm coated gold nanoparticles to act as selective carriers across human brain endothelium and subsequently to enter astrocytes. The transfer rate of glucose-coated gold nanoparticles across primary human brain endothelium was at least three times faster than across non-brain endothelia. Movement of these nanoparticles occurred across the apical and basal plasma membranes via the cytosol with relatively little vesicular or paracellular migration; antibiotics that interfere with vesicular transport did not block migration. The transfer rate was also dependent on the surface coating of the nanoparticle and incubation temperature. Using a novel 3-dimensional co-culture system, which includes primary human astrocytes and a brain endothelial cell line hCMEC/D3, we demonstrated that the glucose-coated nanoparticles traverse the endothelium, move through the extracellular matrix and localize in astrocytes. The movement of the nanoparticles through the matrix was >10 µm/hour and they appeared in the nuclei of the astrocytes in considerable numbers. These nanoparticles have the correct properties for efficient and selective carriers of therapeutic agents across the blood-brain barrier.

Beneficial effects of atorvastatin on myocardial regions with initially low vasodilatory capacity at various stages of coronary artery disease

International Nuclear Information System (INIS)

Wielepp, Peter; Baller, Detlev; Gleichmann, Ulrich; Pulawski, Ewa; Horstkotte, Dieter; Burchert, Wolfgang

2005-01-01

The aim of this study was to analyse non-invasively the regional effect of therapy with an HMG-CoA reductase inhibitor on myocardial blood flow in patients with coronary artery disease (CAD) with special reference to segments with initially substantially impaired vasodilation. The study included 26 patients with untreated hypercholesterolaemia. Coronary angiography revealed CAD in nine patients with stenosis >50% and wall irregularities or minimal stenosis 13 N-ammonia positron emission tomography (PET) studies were performed at rest and under pharmacological stress. Minimum coronary vascular resistance (MCR) and coronary flow reserve (CFR) were determined. Segments were divided into those with normal or near-normal (MBF during adenosine ≥2.0 ml/min/g) and those with abnormal (MBF<2.0 ml/min/g) vasodilator flow response. In CAD patients, 156 segments were analysed, 85 of which had abnormal MBF; in the non-obstructive group, 59 of 297 segments had abnormal MBF. LDL cholesterol decreased after atorvastatin therapy from 186±43 mg/dl to 101±26 mg/dl (p<0.001). In normal segments no significant changes in MBF, CFR and MCR were found. However, initially abnormal segments showed significant improvements in MCR (15%, p<0.0001) and MBF during adenosine (30%, p<0.0001) after therapy. The improvement in regional coronary vasodilator function after atorvastatin in patients with coronary atherosclerosis may be caused, at least in part, by increased flow-mediated (endothelium-dependent) dilation of the total arteriolar and arterial vascular system. These data further support the concept of non-invasive management of stable CAD by statin therapy and life-style modification guided by PET. (orig.)

Maternal melatonin administration mitigates coronary stiffness and endothelial dysfunction, and improves heart resilience to insult in growth restricted lambs.

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Tare, Marianne; Parkington, Helena C; Wallace, Euan M; Sutherland, Amy E; Lim, Rebecca; Yawno, Tamara; Coleman, Harold A; Jenkin, Graham; Miller, Suzanne L

2014-06-15

Intrauterine growth restriction (IUGR) is associated with impaired cardiac function in childhood and is linked to short- and long-term morbidities. Placental dysfunction underlies most IUGR, and causes fetal oxidative stress which may impact on cardiac development. Accordingly, we investigated whether antenatal melatonin treatment, which possesses antioxidant properties, may afford cardiovascular protection in these vulnerable fetuses. IUGR was induced in sheep fetuses using single umbilical artery ligation on day 105-110 of pregnancy (term 147). Study 1: melatonin (2 mg h(-1)) was administered i.v. to ewes on days 5 and 6 after surgery. On day 7 fetal heart function was assessed using a Langendorff apparatus. Study 2: a lower dose of melatonin (0.25 mg h(-1)) was administered continuously following IUGR induction and the ewes gave birth normally at term. Lambs were killed when 24 h old and coronary vessels studied. Melatonin significantly improved fetal oxygenation in vivo. Contractile function in the right ventricle and coronary flow were enhanced by melatonin. Ischaemia-reperfusion-induced infarct area was 3-fold greater in IUGR hearts than in controls and this increase was prevented by melatonin. In isolated neonatal coronary arteries, endothelium-dependent nitric oxide (NO) bioavailability was reduced in IUGR, and was rescued by modest melatonin treatment. Melatonin exposure also induced the emergence of an indomethacin-sensitive vasodilation. IUGR caused marked stiffening of the coronary artery and this was prevented by melatonin. Maternal melatonin treatment reduces fetal hypoxaemia, improves heart function and coronary blood flow and rescues cardio-coronary deficit induced by IUGR. © 2014 The Authors. The Journal of Physiology © 2014 The Physiological Society.

Low-dose ultraviolet-B irradiation of donor corneal endothelium and graft survival

International Nuclear Information System (INIS)

Dana, M.R.; Olkowski, S.T.; Ahmadian, H.; Stark, W.J.; Young, E.M.

1990-01-01

Donor rabbit corneal endothelium was pretreated with different doses of ultraviolet (UV-B) irradiation (302 nm) before grafting to test whether allograft survival could be favorably affected in comparison with untreated corneas grafted into the same recipients. Endothelial rejection was observed in 19 of 32 (59%) eyes that received no treatment compared with five of 32 (16%) eyes that received UV-B (P less than 0.001), and increasing doses of UV-B were associated with lower rejection rates (P less than 0.05). Although exposure of donor endothelium significantly reduced endothelial rejection at all doses tested, it resulted in primary graft failure in a substantial proportion of corneas treated at high doses. Class II (Ia) antigen staining of corneal tissue was present in conjunction with clinical evidence of rejection, and the magnitude of staining correlated with the histologic extent of inflammation. Scanning electron microscopy revealed various endothelial cell surface irregularities and membrane defects in high-dose UV-treated corneas. Endothelial cell cultures exposed in vitro to UV-B light showed a dose-dependent loss in cell viability. These data suggest that UV-B pretreatment of donor corneal endothelium prolongs graft survival but that toxic side effects must be carefully controlled

Jabuticaba-Induced Endothelium-Independent Vasodilating Effect on Isolated Arteries

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Daniela Medeiros Lobo de Andrade

2016-01-01

Full Text Available Abstract Background: Despite the important biological effects of jabuticaba, its actions on the cardiovascular system have not been clarified. Objectives: To determine the effects of jabuticaba hydroalcoholic extract (JHE on vascular smooth muscle (VSM of isolated arteries. Methods: Endothelium-denuded aortic rings of rats were mounted in isolated organ bath to record isometric tension. The relaxant effect of JHE and the influence of K+ channels and Ca2+ intra- and extracellular sources on JHE-stimulated response were assessed. Results: Arteries pre-contracted with phenylephrine showed concentration-dependent relaxation (0.380 to 1.92 mg/mL. Treatment with K+ channel blockers (tetraethyl-ammonium, glibenclamide, 4-aminopyridine hindered relaxation due to JHE. In addition, phenylephrine-stimulated contraction was hindered by previous treatment with JHE. Inhibition of sarcoplasmic reticulum Ca2+ ATPase did not change relaxation due to JHE. In addition, JHE inhibited the contraction caused by Ca2+ influx stimulated by phenylephrine and KCl (75 mM. Conclusion: JHE induces endothelium-independent vasodilation. Activation of K+ channels and inhibition of Ca2+ influx through the membrane are involved in the JHE relaxant effect.

Elevated 20-HETE impairs coronary collateral growth in metabolic syndrome via endothelial dysfunction.

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Joseph, Gregory; Soler, Amanda; Hutcheson, Rebecca; Hunter, Ian; Bradford, Chastity; Hutcheson, Brenda; Gotlinger, Katherine H; Jiang, Houli; Falck, John R; Proctor, Spencer; Schwartzman, Michal Laniado; Rocic, Petra

2017-03-01

Coronary collateral growth (CCG) is impaired in metabolic syndrome (MetS). microRNA-145 (miR-145-Adv) delivery to our rat model of MetS (JCR) completely restored and neutrophil depletion significantly improved CCG. We determined whether low endogenous levels of miR-145 in MetS allowed for elevated production of 20-hydroxyeicosatetraenoic acid (20-HETE), which, in turn, resulted in excessive neutrophil accumulation and endothelial dysfunction leading to impaired CCG. Rats underwent 0-9 days of repetitive ischemia (RI). RI-induced cardiac CYP4F (neutrophil-specific 20-HETE synthase) expression and 20-HETE levels were increased (4-fold) in JCR vs. normal rats. miR-145-Adv and 20-HETE antagonists abolished and neutrophil depletion (blocking antibodies) reduced (~60%) RI-induced increases in CYP4F expression and 20-HETE production in JCR rats. Impaired CCG in JCR rats (collateral-dependent blood flow using microspheres) was completely restored by 20-HETE antagonists [collateral-dependent zone (CZ)/normal zone (NZ) flow ratio was 0.76 ± 0.07 in JCR + 20-SOLA, 0.84 ± 0.05 in JCR + 20-HEDGE vs. 0.11 ± 0.02 in JCR vs. 0.84 ± 0.03 in normal rats]. In JCR rats, elevated 20-HETE was associated with excessive expression of endothelial adhesion molecules and neutrophil infiltration, which were reversed by miR-145-Adv. Endothelium-dependent vasodilation of coronary arteries, endothelial nitric oxide synthase (eNOS) Ser1179 phosphorylation, eNOS-dependent NO ·- production and endothelial cell survival were compromised in JCR rats. These parameters of endothelial dysfunction were completely reversed by 20-HETE antagonism or miR-145-Adv delivery, whereas neutrophil depletion resulted in partial reversal (~70%). We conclude that low miR-145 in MetS allows for increased 20-HETE, mainly from neutrophils, which compromises endothelial cell survival and function leading to impaired CCG. 20-HETE antagonists could provide viable therapy for restoration of CCG in MetS. NEW & NOTEWORTHY

Aerobic exercise reduces oxidative stress and improves vascular changes of small mesenteric and coronary arteries in hypertension.

Science.gov (United States)

Roque, Fernanda R; Briones, Ana M; García-Redondo, Ana B; Galán, María; Martínez-Revelles, Sonia; Avendaño, Maria S; Cachofeiro, Victoria; Fernandes, Tiago; Vassallo, Dalton V; Oliveira, Edilamar M; Salaices, Mercedes

2013-02-01

Regular physical activity is an effective non-pharmacological therapy for prevention and control of hypertension. We investigated the effects of aerobic exercise training in vascular remodelling and in the mechanical and functional alterations of coronary and small mesenteric arteries from spontaneously hypertensive rats (SHR). Normotensive Wistar Kyoto (WKY), SHR and SHR trained on a treadmill for 12 weeks were used to evaluate vascular structural, mechanical and functional properties. Exercise did not affect lumen diameter, wall thickness and wall/lumen ratio but reduced vascular stiffness of coronary and mesenteric arteries from SHR. Exercise also reduced collagen deposition and normalized altered internal elastic lamina organization and expression of MMP-9 in mesenteric arteries from SHR. Exercise did not affect contractile responses of coronary arteries but improved the endothelium-dependent relaxation in SHR. In mesenteric arteries, training normalized the increased contractile responses induced by U46619 and by high concentrations of acetylcholine. In vessels from SHR, exercise normalized the effects of the NADPH oxidase inhibitor apocynin and the NOS inhibitor l-NAME in vasodilator or vasoconstrictor responses, normalized the increased O(2) (-) production and the reduced Cu/Zn superoxide dismutase expression and increased NO production. Exercise training of SHR improves endothelial function and vascular stiffness in coronary and small mesenteric arteries. This might be related to the concomitant decrease of oxidative stress and increase of NO bioavailability. Such effects demonstrate the beneficial effects of exercise on the vascular system and could contribute to a reduction in blood pressure. © 2012 The Authors. British Journal of Pharmacology © 2012 The British Pharmacological Society.

Aerobic exercise reduces oxidative stress and improves vascular changes of small mesenteric and coronary arteries in hypertension

Science.gov (United States)

Roque, Fernanda R; Briones, Ana M; García-Redondo, Ana B; Galán, María; Martínez-Revelles, Sonia; Avendaño, Maria S; Cachofeiro, Victoria; Fernandes, Tiago; Vassallo, Dalton V; Oliveira, Edilamar M; Salaices, Mercedes

2013-01-01

Background and Purpose Regular physical activity is an effective non-pharmacological therapy for prevention and control of hypertension. We investigated the effects of aerobic exercise training in vascular remodelling and in the mechanical and functional alterations of coronary and small mesenteric arteries from spontaneously hypertensive rats (SHR). Experimental Approach Normotensive Wistar Kyoto (WKY), SHR and SHR trained on a treadmill for 12 weeks were used to evaluate vascular structural, mechanical and functional properties. Key Results Exercise did not affect lumen diameter, wall thickness and wall/lumen ratio but reduced vascular stiffness of coronary and mesenteric arteries from SHR. Exercise also reduced collagen deposition and normalized altered internal elastic lamina organization and expression of MMP-9 in mesenteric arteries from SHR. Exercise did not affect contractile responses of coronary arteries but improved the endothelium-dependent relaxation in SHR. In mesenteric arteries, training normalized the increased contractile responses induced by U46619 and by high concentrations of acetylcholine. In vessels from SHR, exercise normalized the effects of the NADPH oxidase inhibitor apocynin and the NOS inhibitor l-NAME in vasodilator or vasoconstrictor responses, normalized the increased O2− production and the reduced Cu/Zn superoxide dismutase expression and increased NO production. Conclusions and Implications Exercise training of SHR improves endothelial function and vascular stiffness in coronary and small mesenteric arteries. This might be related to the concomitant decrease of oxidative stress and increase of NO bioavailability. Such effects demonstrate the beneficial effects of exercise on the vascular system and could contribute to a reduction in blood pressure. PMID:22994554

Morphological and functional evaluation of the bioresorption of the bioresorbable everolimus-eluting vascular scaffold using IVUS, echogenicity and vasomotion testing at two year follow-up: a patient level insight into the ABSORB A clinical trial.

Science.gov (United States)

Sarno, Giovanna; Bruining, Nico; Onuma, Yoshinobu; Garg, Scot; Brugaletta, Salvatore; De Winter, Sebastiaan; Regar, Evelyn; Thuesen, Leif; Dudek, Dariusz; Veldhof, Susan; Dorange, Cecile; Garcia-Garcia, Hector M; Ormiston, John A; Serruys, Patrick W

2012-01-01

The aim of this study was to describe vaso-reactivity (by Acetylcholine and Methergine tests) at 2 year follow-up in parallel with the individual changes in the echogenicity characteristics of the polymer struts of the everolimus eluting bioresorbable vascular scaffold (BVS), from post-treatment to 2 year follow-up, in patients enrolled in the ABSORB Cohort A study. Intravascular ultrasound assessment was performed with a phased array catheter (EagleEye, Volcano Corporation, Cordova, CA, USA) with automated pullback at 0.5 mm per second. The % ratio at 6 months and 2 years [(Scaffold Area post PCI- Lumen Area)/Scaffold Area post PCI] was calculated as a measure of scaffold shrinkage. The % change of hyperechogenicity was defined as: ([post-procedural hyperechogenicity] - [2 year follow up hyperechogenicity])/[post-procedural hyperechogenicity]) × 100. The vasomotion test with intracoronary acetylcholine (10(-6) M) or intravenous methergine (0.4 mg) was performed at 2 years. Overall nine patients received all these analyses and were enrolled in the present analysis. A 50-96% reduction in hyperechogenicity was observed between baseline and 2 years, which corresponded to a change in vasoreactivity between 2 and 22%. A vasoconstriction of the scaffolded segment was observed in the 5 patients, who underwent the methergine test, with a mean decrease in lumen diameter after methergine of 9 ± 7% (P = 0.06), while vasodilatation occurred in the 4 patients who underwent the acetylcholine test with a mean increase in lumen diameter after acetylcholine of 8 ± 5% (P = 0.125). Bioresorption of the BVS is accompanied by re-establishment of both endothelial and non-endothelial dependent vasomotion.

HOXB4 Promotes Hemogenic Endothelium Formation without Perturbing Endothelial Cell Development

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Nadine Teichweyde

2018-03-01

Full Text Available Summary: Generation of hematopoietic stem cells (HSCs from pluripotent stem cells, in vitro, holds great promise for regenerative therapies. Primarily, this has been achieved in mouse cells by overexpression of the homeotic selector protein HOXB4. The exact cellular stage at which HOXB4 promotes hematopoietic development, in vitro, is not yet known. However, its identification is a prerequisite to unambiguously identify the molecular circuits controlling hematopoiesis, since the activity of HOX proteins is highly cell and context dependent. To identify that stage, we retrovirally expressed HOXB4 in differentiating mouse embryonic stem cells (ESCs. Through the use of Runx1(−/− ESCs containing a doxycycline-inducible Runx1 coding sequence, we uncovered that HOXB4 promoted the formation of hemogenic endothelium cells without altering endothelial cell development. Whole-transcriptome analysis revealed that its expression mediated the upregulation of transcription of core transcription factors necessary for hematopoiesis, culminating in the formation of blood progenitors upon initiation of Runx1 expression. : In this article, Klump and colleagues demonstrate that the human homeotic selector protein HOXB4 promotes ESC-derived hematopoiesis by inducing hemogenic endothelium formation, in vitro. It propels hematopoietic specification by upregulating the transcription of genes essential for hematopoietic development, such as those encoding members of the so-called heptad transcription factors. Keywords: HOXB4, hematopoietic stem cells, hemangioblast, hemogenic endothelium, hematopoietic specification, EHT, RUNX1, pluripotent stem cells

Beneficial effects of atorvastatin on myocardial regions with initially low vasodilatory capacity at various stages of coronary artery disease

Energy Technology Data Exchange (ETDEWEB)

Wielepp, Peter [Ruhr-University Bochum, Institute of Molecular Biophysics, Radiopharmacy and Nuclear Medicinea, Bad Oeynhausen (Germany); Heart and Diabetes Center North Rhine-Westphalia, Bad Oeynhausen (Germany); Baller, Detlev [Ruhr-University Bochum, Department of Cardiology, Heart and Diabetes Center North Rhine-Westphalia, Bad Oeynhausen (Germany); Heart and Diabetes Center North Rhine-Westphalia, Bad Oeynhausen (Germany); Gleichmann, Ulrich; Pulawski, Ewa; Horstkotte, Dieter [Ruhr-University Bochum, Department of Cardiology, Heart and Diabetes Center North Rhine-Westphalia, Bad Oeynhausen (Germany); Burchert, Wolfgang [Ruhr-University Bochum, Institute of Molecular Biophysics, Radiopharmacy and Nuclear Medicinea, Bad Oeynhausen (Germany)

2005-12-01

The aim of this study was to analyse non-invasively the regional effect of therapy with an HMG-CoA reductase inhibitor on myocardial blood flow in patients with coronary artery disease (CAD) with special reference to segments with initially substantially impaired vasodilation. The study included 26 patients with untreated hypercholesterolaemia. Coronary angiography revealed CAD in nine patients with stenosis >50% and wall irregularities or minimal stenosis <30% in 17 patients. Before and 4.6{+-}1.8 months after atorvastatin therapy,{sup 13}N-ammonia positron emission tomography (PET) studies were performed at rest and under pharmacological stress. Minimum coronary vascular resistance (MCR) and coronary flow reserve (CFR) were determined. Segments were divided into those with normal or near-normal (MBF during adenosine {>=}2.0 ml/min/g) and those with abnormal (MBF<2.0 ml/min/g) vasodilator flow response. In CAD patients, 156 segments were analysed, 85 of which had abnormal MBF; in the non-obstructive group, 59 of 297 segments had abnormal MBF. LDL cholesterol decreased after atorvastatin therapy from 186{+-}43 mg/dl to 101{+-}26 mg/dl (p<0.001). In normal segments no significant changes in MBF, CFR and MCR were found. However, initially abnormal segments showed significant improvements in MCR (15%, p<0.0001) and MBF during adenosine (30%, p<0.0001) after therapy. The improvement in regional coronary vasodilator function after atorvastatin in patients with coronary atherosclerosis may be caused, at least in part, by increased flow-mediated (endothelium-dependent) dilation of the total arteriolar and arterial vascular system. These data further support the concept of non-invasive management of stable CAD by statin therapy and life-style modification guided by PET. (orig.)

Age-dependent trends in postoperative mortality and preoperative comorbidity in isolated coronary artery bypass surgery

DEFF Research Database (Denmark)

Thorsteinsson, Kristinn; Fonager, Kirsten; Mérie, Charlotte

2016-01-01

OBJECTIVES: An increasing number of octogenarians are being subjected to coronary artery bypass grafting (CABG). The purpose of this study was to examine age-dependent trends in postoperative mortality and preoperative comorbidity over time following CABG. METHODS: All patients who underwent isol...

Junctional transfer in cultured vascular endothelium: II. Dye and nucleotide transfer

International Nuclear Information System (INIS)

Larson, D.M.; Sheridan, J.D.

1985-01-01

Vascular endothelial cultures, derived from large vessels, retain many of the characteristics of their in vivo counterparts. However, the observed reduction in size and complexity of intercellular gap and tight junctions in these cultured cells suggests that important functions, thought to be mediated by these structures, may be altered in vitro. In continuing studies on intercellular communication in vessel wall cells, the authors have quantitated the extent of junctional transfer of small molecular tracers (the fluorescent dye Lucifer Yellow CH and tritiated uridine nucleotides) in confluent cultures of calf aortic (BAEC) and umbilical vein (BVEC) endothelium. Both BAEC and BVEC show extensive (and quantitatively equivalent) dye and nucleotide transfer. As an analogue of intimal endothelium, the authors have also tested dye transfer in freshly isolated sheets of endothelium. Transfer in BAEC and BVEC sheets was more rapid, extensive and homogeneous than in the cultured cells, implying a reduction in molecular coupling as endothelium adapts to culture conditions. In addition, they have documented heterocellular nucleotide transfer between cultured endothelium and vascular smooth muscle cells, of particular interest considering the prevalence of ''myo-endothelial'' junctions in vivo. These data yield further information on junctional transfer in cultured vascular endothelium and have broad implications for the functional integration of the vessel wall in the physiology and pathophysiology of the vasculature

Coronary artery disease and its association with Vitamin D deficiency

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Ramesh Aggarwal

2016-01-01

Full Text Available Coronary artery disease (CAD has become the latest scourge of humankind and referred to in this article as CAD, is the end result of the accumulation of atheromatous plaques within the walls of coronary arteries that supply the myocardium, a process also known as atherosclerosis and manifests mostly in the form of chronic stable angina or acute coronary syndrome. Vitamin D has attracted considerable interest recently due to its role in a number of extraskeletal disease processes including multiple sclerosis, malignancies, diabetes mellitus, and CAD. It is also known as sunshine vitamin due to its production in the body following exposure to ultraviolet rays, and it is a unique vitamin as it acts like a hormone with its receptor present in a wide range of tissues including endothelium, which is the important mediator of atherosclerosis and subsequent CAD. A large number of studies conducted in the past have provided the basic scientific framework and this article attempts to explore the role of Vitamin D deficiency in the pathogenesis of CAD and stresses the need for further research to fill up gap in our knowledge.

Endothelial dysfunction, carotid artery plaque burden, and conventional exercise-induced myocardial ischemia as predictors of coronary artery disease prognosis

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Ishihara Masayuki

2008-12-01

Full Text Available Abstract Background While both flow-mediated vasodilation (FMD in the brachial artery (BA, which measures endothelium-dependent vasodilatation, and intima-media thickness (IMT in the carotid artery are correlated with the prognosis of coronary artery disease (CAD, it is not clear which modality is a better predictor of CAD. Furthermore, it has not been fully determined whether either of these modalities is superior to conventional ST-segment depression on exercise stress electrocardiogram (ECG as a predictor. Thus, the goal of the present study was to compare the predictive value of FMD, IMT, and stress ECG for CAD prognosis. Methods and Results A total of 103 consecutive patients (62 ± 9 years old, 79 men with clinically suspected CAD had FMD and nitroglycerin-induced dilation (NTG-D in the BA, carotid artery IMT measurement using high-resolution ultrasound, and exercise treadmill testing. The 73 CAD patients and 30 normal coronary patients were followed for 50 ± 15 months. Fifteen patients had coronary events during this period (1 cardiac death, 2 non-fatal myocardial infarctions, 3 acute heart failures, and 9 unstable anginas. On Kaplan-Meier analysis, only FMD and stress ECG were significant predictors for cardiac events. Conclusion Brachial endothelial function as reflected by FMD and conventional exercise stress testing has comparable prognostic value, whereas carotid artery plaque burden appears to be less powerful for predicting future cardiac events.

Role of endothelial function in coronary slow-flow phenomenon with angiographically normal coronaries

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Srikanth Nathani

2016-01-01

Conclusion: Coronary slow flow phenomenon is a marker of atherosclerosis (as documented by carotid intima media thickness and our study has also shown that endothelial function is significantly impaired in patients with coronary slow flow (as documented by impaired endothelial dependent vasodilatation than that of patients with normal epicardial coronaries with normal flow.

Acetylcholine versus cold pressor testing for evaluation of coronary endothelial function.

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Ahmed AlBadri

Full Text Available Assessment of coronary endothelial function with intracoronary acetylcholine (IC-Ach provides diagnostic and prognostic data in patients with suspected coronary microvascular dysfunction (CMD, but is often not feasible due in part to the time and expertise needed for pharmacologic mixing. Cold pressor testing (CPT is a simple and safe stimulus useful for either invasive or non-invasive endothelial function testing and myocardial perfusion imaging but has not been specifically evaluated among symptomatic women with signs of ischemic heart disease (IHD who have no obstructive coronary artery disease (CAD.163 women with signs and symptoms of IHD and no obstructive CAD from the NHLBI- Women's Ischemia Syndrome Evaluation-Coronary Vascular Dysfunction (WISE-CVD study underwent coronary reactivity testing with a Doppler flow wire (FloWire® Volcano, San Diego, CA in the proximal left anterior descending artery. Coronary artery diameter and coronary blood flow (CBF assessed by core lab using QCA before and after IC-Ach (18.2 μg/ml infused over 3 minutes and during CPT.Mean age was 55 ± 12 years. Rate pressure product (RPP in response to IC-Ach did not change (baseline to peak, P = 0.26, but increased during CPT (363±1457; P = 0.0028. CBF in response to CPT was poorly correlated to IC-Ach CBF. Change in coronary artery diameter after IC-Ach correlated with change after CPT (r = 0.59, P<0.001. The correlation coefficient was stronger in subjects with coronary dilation to IC-Ach (r = 0.628, P<0.001 versus those without dilation (r = 0.353, P = 0.002, suggesting that other factors may be important to this relationship when endothelium is abnormal.In women with no obstructive CAD and suspected CMD, coronary diameter changes with IC-Ach and CPT are moderately-well correlated suggesting that CPT testing may be of some use, particularly among patients with normal endothelial function, however, not an alternative to IC-Ach for diagnosis of coronary

Hypotensive effect and endothelium-dependent vascular action of leaves of Alpinia purpurata (Vieill K. Schum

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Alessandra Tesch da Silva

2014-04-01

Full Text Available The aims of this study were to evaluate the chemical profile, vascular reactivity, and acute hypotensive effect (AHE of the ethanolic extract of leaves of Alpinia purpurata (Vieill K. Schum (EEAP. Its chemical profile was evaluated using HPLC-UV, ICP-OES, and colorimetric quantification of total flavonoids and polyphenols. The vascular reactivity of the extract was determined using the mesenteric bed isolated from WKY. AHE dose-response curves were obtained for both EEAP and inorganic material isolated from AP (IAP in WKY and SHR animals. Cytotoxic and mutagenic safety levels were determined by the micronucleus test. Rutin-like flavonoids were quantified in the EEAP (1.8 ± 0.03%, and the total flavonoid and polyphenol ratios were 4.1 ± 1.8% and 5.1 ± 0.3%, respectively. We observed that the vasodilation action of EEAP was partially mediated by nitric oxide (·NO. The IAP showed the presence of calcium (137.76 ± 4.08 μg mg-1. The EEAP and IAP showed an AHE in WKY and SHR animals. EEAP did not have cytotoxic effects or cause chromosomic alterations. The AHE shown by EEAP could result from its endothelium-dependent vascular action. Rutin-like flavonoids, among other polyphenols, could contribute to these biological activities, and the calcium present in EEAP could act in a synergistic way.

Relative permeability of the endothelium and epithelium of rabbit lungs

International Nuclear Information System (INIS)

Effros, R.M.; Mason, G.R.; Silverman, P.; Hukkanen, J.

1986-01-01

Electron micrographic studies of lungs suggest that the epithelial cells are more tightly joined than the underlying endothelium, and macromolecules penetrate the endothelium more readily than the epithelium. Comparisons of epithelial and endothelial permeability to small molecules have been based upon the relative rates at which solutes traverse the alveolar-capillary barrier in fluid filled lungs and those at which they equilibrate across the capillaries in air-filled lungs. Because the former process is much slower than the latter, it has been concluded that the epithelium is less permeable to small solutes than the endothelium. However this difference may be related to inadequate access of solutes to airway surfaces. In this study, solute losses from the vascular space were compared to those from the airspace in perfused, fluid-filled rabbit lungs. 36 Cl - and 125 I - were lost from air-spaces almost twice as rapidly as 22 Na + . In contrast, the endothelium is equally permeable to 22 Na + and these anions. Loss of 3 H-mannitol from the perfusate resembled that of 22 Na + for about 30 minutes, after which diffusion of 3 H-mannitol into the tissue nearly ceased. These observations suggest that the epithelium is more permselective than the endothelium. By resisting solute and water transport, the epithelium tends to prevent alveolar flooding and confines edema to the interstitium, where it is less likely to interfere with gas exchange

Effects of Buddhism walking meditation on depression, functional fitness, and endothelium-dependent vasodilation in depressed elderly.

Science.gov (United States)

Prakhinkit, Susaree; Suppapitiporn, Siriluck; Tanaka, Hirofumi; Suksom, Daroonwan

2014-05-01

The objectives of this study were to determine the effects of the novel Buddhism-based walking meditation (BWM) and the traditional walking exercise (TWE) on depression, functional fitness, and vascular reactivity. This was a randomized exercise intervention study. The study was conducted in a university hospital setting. Forty-five elderly participants aged 60-90 years with mild-to-moderate depressive symptoms were randomly allocated to the sedentary control, TWE, and BWM groups. The BWM program was based on aerobic walking exercise incorporating the Buddhist meditations performed 3 times/week for 12 weeks. Depression score, functional fitness, and endothelium-dependent vasodilation as measured by the flow-mediated dilation (FMD) were the outcome measures used. Muscle strength, flexibility, agility, dynamic balance, and cardiorespiratory endurance increased in both exercise groups (p<0.05). Depression score decreased (p<0.05) only in the BWM group. FMD improved (p<0.05) in both exercise groups. Significant reduction in plasma cholesterol, triglyceride, high-density lipoprotein cholesterol, and C-reactive protein were found in both exercise groups, whereas low-density lipoprotein cholesterol, cortisol, and interleukin-6 concentrations decreased only in the BWM group. Buddhist walking meditation was effective in reducing depression, improving functional fitness and vascular reactivity, and appears to confer greater overall improvements than the traditional walking program.

Variation in the Sodium-Dependent Vitamin C Transporter 2 Gene Is Associated with Risk of Acute Coronary Syndrome among Women

DEFF Research Database (Denmark)

Dalgård, Christine; Christiansen, Lene; Vogel, Ulla

2013-01-01

Vitamin C is associated with a lower risk of coronary heart disease possibly due to its anti-oxidative effects, beneficial effects on endothelial function and importance in collagen synthesis. The sodium-dependent vitamin C transporter 2 is responsible for the transport of vitamin C into various...... cells and malfunction of this protein leads to reduced vitamin C in tissue, including the arterial wall. We tested the hypothesis that candidate variations rs6139591 and rs1776964 in the gene coding for sodium-dependent vitamin C transporter 2 are associated with development of acute coronary syndrome....

Influence of endothelium on the membrane-stabilizing effect of calcium

African Journals Online (AJOL)

Dr Olaleye

increase in [Ca2+]o (low bicarbonate PSS) from 5.0 to 25.0mM in rings with intact endothelium resulted in relaxation responses. These relaxation responses were attenuated in endothelium- denuded rings as well as following exposure to methylene blue. Conclusion: The results show that relaxation responses induced by ...

Effects of nicorandil on coronary collateral circulation depend on the donor arteries

International Nuclear Information System (INIS)

Umezawa, Shigeo; Ogawara, Shigeko; Okamoto, Yoshihiro; Igawa, Masayuki; Aonuma, Kazutaka; Inada, Mihoe; Korenaga, Masayoshi; Hiroe, Michiaki; Marumo, Fumiaki.

1996-01-01

The effects of nicorandil on coronary collateral circulation during exercise-induced ischemia were compared between the different donor arteries in 13 patients with effort angina, 7 with complete obstruction of the left anterior descending artery (LAD) with well-developed collateral vessels from the right coronary artery (RCA) (LAD group), and 6 with complete occlusion of the RCA (segment 2-3) with well-developed collateral vessels from the LAD (RCA group). Initial percentage thallium (%Tl) uptake (thallium-201 single photon emission computed tomography) and washout rate were measured in the anterior, septal and posterior regions during ergometer exercise. The submaximal treadmill exercise test was also performed using a cardiopulmonary monitoring system to measure Vo 2 at anaerobic threshold (AT). After the controls were obtained, nicorandil (15 mg/day) was administered for 4 weeks, during which ergometer exercise and treadmill exercise tests were carried out repeatedly. A significant improvement of initial %Tl uptake on exercise was observed in the LAD group with nicorandil therapy, but no improvement was shown in the RCA group. The AT significantly increased after nicorandil treatment in the LAD group (13.9±0.38 → 16.8±1.18 ml/min/kg), reflecting the improvement of cardiac function through the increased collateral flow. However, in the RCA group, it remained unchanged, suggesting no improvement of cardiac function. Nicorandil was effective to increase collateral flow from the RCA, but ineffective on that from the LAD. Nicorandil is an effective coronary dilator and is reported to affect both large and small coronary arteries. The effect on the collateral circulation is dependent on the donor artery supplying different areas. The vasodilator effect of nicorandil is mainly on the LAD, which is large enough to supply blood to a wider area of the heart, rather than the RCA. (author)

An in vitro model of hemogenic endothelium commitment and hematopoietic production

NARCIS (Netherlands)

Yvernogeau, Laurent; Gautier, Rodolphe; Khoury, Hanane; Menegatti, Sara; Schmidt, Melanie; Gilles, Jean Francois; Jaffredo, Thierry

2016-01-01

Adult-type hematopoietic stem and progenitor cells are formed during ontogeny from a specialized subset of endothelium, termed the hemogenic endothelium, via an endothelial-to-hematopoietic transition (EHT) that occurs in the embryonic aorta and the associated arteries. Despite efforts to generate

Statistical dependence of clinical data on the chosen treatment of patients with a multivessel coronary artery disease.

Science.gov (United States)

Walichiewicz, P; Wodniecki, J; Szczurek-Katański, K; Jacheć, W; Nowalany-Kozielska, E; Trzeciak, P; Janik, J

2001-01-01

In this study we tried to check which clinical data are connected with the choice of treatment in patients with a multivessel coronary artery disease. The data of 137 patients with a multivessel coronary artery disease, were analysed retrospectively. The patients were divided into three groups: treated conservatively, CABG and PTCA. Multivessel coronary artery disease was recognised when there were atherosclerotic changes in more a 2 vessels with a not less a 2 mm in diameter. Patients with previous CABG or a left main coronary artery disease were excluded. The data were analysed by means of several methods, variance analysis, correlation analysis, discriminant functions, chi-square test and T-Student test. For treatment decision making in multivessel coronary artery disease of statistical significance were: the state of the left anterior descendent artery below the first diagonal branch, the state of the first diagonal branch and peripheral parts of the left anterior descendent artery and right coronary artery, the systolic function of the antero-lateral, apical and phrenic segments of the left ventricle, the global left ventricular ejection fraction in angiography and echocardiography, local systolic disturbances of the left ventricular observed in echocardiography, the coexistence of symptoms of heart failure as well as unstable angina. Treatment decision making will always depend not only on diagnostic procedures but also on all the clinical data about the patient and the experience of coworking cardiology and surgery centres.

In vitro study of histamine and histamine receptor ligands influence on the adhesion of purified human eosinophils to endothelium.

Science.gov (United States)

Grosicki, Marek; Wójcik, Tomasz; Chlopicki, Stefan; Kieć-Kononowicz, Katarzyna

2016-04-15

It is a well-known fact that histamine is involved in eosinophil-dependent inflammatory responses including cellular chemotaxis and migration. Nevertheless, the relative role of histamine receptors in the mechanisms of eosinophils adhesion to endothelial cells is not known. Therefore the aim of presented study was to examine the effect of selective histamine receptors ligands on eosinophils adhesion to endothelium. For that purpose the highly purified human eosinophils have been isolated from the peripheral blood. The viability and functional integrity of isolated eosinophils have been validated in several tests. Histamine as well as 4-methylhistamine (selective H4 agonist) in concentration-dependent manner significantly increased number of eosinophils that adhere to endothelium. Among the selective histamine receptors antagonist or H1 inverse agonist only JNJ7777120 (histamine H4 antagonist) and thioperamide (dual histamine H3/H4 antagonist) had direct effect on eosinophils adhesion to endothelial cells. Antagonists of H1 (diphenhydramine, mepyramine) H2 (ranitidine and famotidine) and H3 (pitolisant) histamine receptors were ineffective. To the best of our knowledge, this is the first study to demonstrate that histamine receptor H4 plays a dominant role in histamine-induced eosinophils adhesion to endothelium. Copyright © 2016 Elsevier B.V. All rights reserved.

Regulation of the renin–angiotensin system in coronary atherosclerosis: A review of the literature

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Ramadan A Hammoud

2008-01-01

Full Text Available Ramadan A Hammoud, Christopher S Vaccari, Sameer H Nagamia, Bobby V KhanEmory University School of Medicine, Division of Cardiology, Grady Memorial Hospital Vascular Research Laboratory, Atlanta, Georgia, USAAbstract: Activation of the renin–angiotensin system (RAS is significant in the pathogenesis of cardiovascular disease and specifically coronary atherosclerosis. There is strong evidence that the RAS has effects on the mechanisms of action of atherosclerosis, including fibrinolytic balance, endothelial function, and plaque stability. Pharmacological inhibition of the renin angiotensin system includes angiotensin converting enzyme (ACE inhibitors, angiotensin receptor blockers (ARBs, and renin inhibitors. These agents have clinical benefits in reducing morbidity and mortality in the management of hypertension. In addition, ACE inhibitors and ARBs have shown to be effective in the management of congestive heart failure and acute myocardial infarction. This review article discusses the biochemical and molecular mechanisms involving the RAS in coronary atherosclerosis as well as the effects of RAS inhibition in clinical studies involving coronary atherosclerosis.Keywords: angiotensin II, atherosclerosis, endothelium, inflammation, vasculature

PSYCHOLOGICAL FEATURES IN PATIENTS WITH CORONARY HEART DISEASE (MEN AND WOMEN PRIOR TO CORONARY ARTERY BYPASS GRAFTING DEPENDING ON THEIR INVOLVEMENT IN THE INDIVIDUAL PSYCHO-CORRECTION PROGRAM

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D. A. Starunskaya

2017-01-01

Full Text Available Importance. The study of psychological characteristics of patients is important for the creation and planning of psychological correction and improve the efficiency of the treatment of coronary heart disease.Тhe purpose. This research is devoted to the study of the psychological features in patients with coronary artery disease (CHD in the preoperative period, depending on their involvement in psycho-correction program.Material and methods. We observed 30 patients with coronary heart disease before coronary bypass surgery. Clinical-psychological method (observation, conversation and psychological testing were used.Results  and conclusions. We found that patients who participated in psycho-correction program had lower values of «anxiety», «phobic anxiety» and «obsessive-compulsive» symptoms. In both groups of patients, on average, we identified the prevalence  of the coping-strategies «self-control» and «planning solution». Furthermore, on average, the «self-awareness» and «extraversion» were more manifested features in the structure of the personality traits of the surveyed patients. The revealed features should be taken into account in planning the programs of psycho-correction for patients with CHD prior to CABG surgery.

Endothelium-Independent Vasorelaxant Effect of Ligusticum jeholense Root and Rhizoma on Rat Thoracic Aorta

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Bumjung Kim

2015-06-01

Full Text Available Ligusticum jeholense has been used as the traditional medicine ‘Go-Bon’ (Chinese name, Gao-ben in China and Korea. Considering the increased use of medicinal herbs to treat hypertension, in this study, we aimed to investigate the mechanisms of the vasorelaxation effect caused by L. jeholense. We tested the methanol (MeOH extract of L. jeholense root and rhizoma for vasorelaxant effects; while using an isolated organ-chamber technique, L. jeholense extract (LJE induced relaxation in the rat aortic rings by stimulating vascular endothelial and smooth muscle cells. LJE showed concentration-dependent relaxant effects on endothelium-intact and endothelium-denuded aortic rings pre-contracted with both phenylephrine (PE and potassium chloride (KCl in Krebs-Henseleit (KH buffer. The vasorelaxant effect of LJE was partly attenuated by pre-treatment with glibenclamide or 4-aminopyridine (4-AP as K+ channel blockers. Moreover, LJE showed concentration-dependent inhibition of vasoconstriction by Ca2+ supplementation in the aortic rings that were pre-contracted with PE or KCl in Ca2+-free KH buffer. In addition, a combination of LJE and nifedipine, pre-incubated further, decreased PE-induced contractions. The results suggested that LJE-induced vasorelaxation were related to blocking K+ channels and inhibiting entry of extracellular Ca2+ via receptor-operative Ca2+ channels (ROCCs or voltage-dependent Ca2+ channels (VDCCs.

Confocal microscopy and electrophysiological study of single patient corneal endothelium cell cultures

Science.gov (United States)

Tatini, Francesca; Rossi, Francesca; Coppi, Elisabetta; Magni, Giada; Fusco, Irene; Menabuoni, Luca; Pedata, Felicita; Pugliese, Anna Maria; Pini, Roberto

2016-04-01

The characterization of the ion channels in corneal endothelial cells and the elucidation of their involvement in corneal pathologies would lead to the identification of new molecular target for pharmacological treatments and to the clarification of corneal physiology. The corneal endothelium is an amitotic cell monolayer with a major role in preserving corneal transparency and in regulating the water and solute flux across the posterior surface of the cornea. Although endothelial cells are non-excitable, they express a range of ion channels, such as voltage-dependent Na+ channels and K+ channels, L-type Ca2 channels and many others. Interestingly, purinergic receptors have been linked to a variety of conditions within the eye but their presence in the endothelium and their role in its pathophysiology is still uncertain. In this study, we were able to extract endothelial cells from single human corneas, thus obtaining primary cultures that represent the peculiarity of each donor. Corneas were from tissues not suitable for transplant in patients. We characterized the endothelial cells by confocal microscopy, both within the intact cornea and in the primary endothelial cells cultures. We also studied the functional role of the purinergic system (adenosine, ATP and their receptors) by means of electrophysiological recordings. The experiments were performed by patch clamp recordings and confocal time-lapse microscopy and our results indicate that the application of purinergic compounds modulates the amplitude of outward currents in the isolated endothelial cells. These findings may lead to the proposal of new therapies for endothelium-related corneal diseases.

Hypoxia and hydrogen sulfide differentially affect normal and tumor-derived vascular endothelium

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Serena Bianco

2017-08-01

Full Text Available Background: endothelial cells play a key role in vessels formation both under physiological and pathological conditions. Their behavior is influenced by blood components including gasotransmitters (H2S, NO and CO. Tumor cells are subjected to a cyclic shift between pro-oxidative and hypoxic state and, in this scenario, H2S can be both cytoprotective and detrimental depending on its concentration. H2S effects on tumors onset and development is scarcely studied, particularly concerning tumor angiogenesis. We previously demonstrated that H2S is proangiogenic for tumoral but not for normal endothelium and this may represent a target for antiangiogenic therapeutical strategies. Methods: in this work, we investigate cell viability, migration and tubulogenesis on human EC derived from two different tumors, breast and renal carcinoma (BTEC and RTEC, compared to normal microvascular endothelium (HMEC under oxidative stress, hypoxia and treatment with exogenous H2S. Results: all EC types are similarly sensitive to oxidative stress induced by hydrogen peroxide; chemical hypoxia differentially affects endothelial viability, that results unaltered by real hypoxia. H2S neither affects cell viability nor prevents hypoxia and H2O2-induced damage. Endothelial migration is enhanced by hypoxia, while tubulogenesis is inhibited for all EC types. H2S acts differentially on EC migration and tubulogenesis. Conclusions: these data provide evidence for a great variability of normal and altered endothelium in response to the environmental conditions. Keywords: Hydrogen sulfide, Human microvascular endothelial cells, Human breast carcinoma-derived EC, Human renal carcinoma-derived EC, Tumor angiogenesis

Visualization of three pathways for macromolecule transport across cultured endothelium and their modification by flow.

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Ghim, Mean; Alpresa, Paola; Yang, Sung-Wook; Braakman, Sietse T; Gray, Stephen G; Sherwin, Spencer J; van Reeuwijk, Maarten; Weinberg, Peter D

2017-11-01

Transport of macromolecules across vascular endothelium and its modification by fluid mechanical forces are important for normal tissue function and in the development of atherosclerosis. However, the routes by which macromolecules cross endothelium, the hemodynamic stresses that maintain endothelial physiology or trigger disease, and the dependence of transendothelial transport on hemodynamic stresses are controversial. We visualized pathways for macromolecule transport and determined the effect on these pathways of different types of flow. Endothelial monolayers were cultured under static conditions or on an orbital shaker producing different flow profiles in different parts of the wells. Fluorescent tracers that bound to the substrate after crossing the endothelium were used to identify transport pathways. Maps of tracer distribution were compared with numerical simulations of flow to determine effects of different shear stress metrics on permeability. Albumin-sized tracers dominantly crossed the cultured endothelium via junctions between neighboring cells, high-density lipoprotein-sized tracers crossed at tricellular junctions, and low-density lipoprotein-sized tracers crossed through cells. Cells aligned close to the angle that minimized shear stresses across their long axis. The rate of paracellular transport under flow correlated with the magnitude of these minimized transverse stresses, whereas transport across cells was uniformly reduced by all types of flow. These results contradict the long-standing two-pore theory of solute transport across microvessel walls and the consensus view that endothelial cells align with the mean shear vector. They suggest that endothelial cells minimize transverse shear, supporting its postulated proatherogenic role. Preliminary data show that similar tracer techniques are practicable in vivo. NEW & NOTEWORTHY Solutes of increasing size crossed cultured endothelium through intercellular junctions, through tricellular

Coronary blood flow and coronary stenosis correlations in ischemic heart patients

International Nuclear Information System (INIS)

Manukov, I.

2003-01-01

The aim of the study is the assessment of the methodology for the C-TIMI frame count by Gibson for easy and fast determination of the coronary blood flow during a selective coronary angiography. 75 patient have been studied with one-branch affection of the coronary arteries. The criteria for exclusion are: myocardial hypertrophy, valve lesions, myocardial infarction and dyslipidemia. Depending of the characteristics of the coronary stenotic changes, the patients have been divided into two groups: 1) Patients with 'ordinary' stenosis of the coronary artery and 2) Patients with 'complex' stenosis. The severity of the stenotic changes in percents is the same for the two groups - 78%±13% vs 81±12%, respectively. In the first group a pronounced correlation is observed between the severity of the coronary stenosis and the slowing of the coronary blood flow. The 'threshold' stenotic level is 89%. In the second group the lowest value of the coronary stenosis is 73% (p>0.01 vs group 1). No correlation is observed between the severity of the coronary stenosis and the slowing of the coronary blood flow. A conclusion is made that the Gibson method for the assessment of the blood flow is convenient for the daily practice not only for the assessment of the significance of the coronary changes, but also for fast analysis of the achieved reconstruction of the coronary arteries after angioplasty. Additional studies of the significance of the different signs of 'complexity' of the coronary stenosis for the slowing of the blood flow are necessary

Thrombin-induced increase in albumin permeability across the endothelium

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Garcia, J.G.; Siflinger-Birnboim, A.; Bizios, R.; Del Vecchio, P.J.; Fenton, J.W. II; Malik, A.B.

1986-01-01

We studied the effect of thrombin on albumin permeability across the endothelial monolayer in vitro. Bovine pulmonary artery endothelial cells were grown on micropore membranes. Morphologic analysis confirmed the presence of a confluent monolayer with interendothelial junctions. Albumin permeability was measured by the clearance of 125I-albumin across the endothelial monolayer. The control 125I-albumin clearance was 0.273 +/- 0.02 microliter/min. The native enzyme, alpha-thrombin (10(-6) to 10(-10) M), added to the luminal side of the endothelium produced concentration-dependent increases in albumin clearance (maximum clearance of 0.586 +/- 0.08 microliter/min at 10(-6) M). Gamma (gamma) thrombin (10(-6) M and 10(-8) M), which lacks the fibrinogen recognition site, also produced a concentration-dependent increase in albumin clearance similar to that observed with alpha-thrombin. Moreover, the two proteolytically inactive forms of the native enzyme, i-Pr2 P-alpha-thrombin and D-Phe-Pro-Arg-CH2-alpha-thrombin, increased the 125I-albumin clearance (0.610 +/- 0.09 microliter/min and 0.609 +/- 0.02 microliter/min for i-Pr2 P-alpha-thrombin and D-Phe-Pro-Arg-CH2-alpha-thrombin at 10(-6) M, respectively). Since the modified forms of thrombin lack the fibrinogen recognition and active serine protease sites, the results indicate that neither site is required for increased albumin permeability. The increase in albumin clearance with alpha-thrombin was not secondary to endothelial cell lysis because lactate dehydrogenase concentration in the medium following thrombin was not significantly different from baseline values. There was also no morphological evidence of cell lysis. Moreover, the increase in 125I-albumin clearance induced by alpha-thrombin was reversible by washing thrombin from the endothelium

Indications for coronary angiography

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Kaltenbach, M.; Vallbracht, C.

1985-01-01

Today selective coronary angiography, introduced by Sones in 1957, is used as clinical routine for diagnosing morphological changes in the coronary arteries. Hitherto, more recent techniques such as digital subtraction angiography cannot provide comparable information. Strict criteria for its indication depending on possible therapeutic consequences, have to be applied, although the risk is low with a letality of 0.01 to 0.05 percent. Radionuclear investigations can be used as additional tool in selected cases. The careful indication for coronary angiography usually implies the possible need for coronary bypass graft surgery of balloon angioplasty. (orig./MG) [de

Resistin Enhances Inflammatory Cytokine Production in Coronary Artery Tissues by Activating the NF-κB Signaling

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Fang Gao

2016-01-01

Full Text Available Purpose. Kawasaki disease (KD is a systemic vasculitis and is a leading cause of coronary artery lesions (CALs in childhood. Our previous study has shown higher levels of serum Resistin in KD patients with coronary aneurysm. This study aimed at examining the association of Resistin with inflammatory cytokine expression in mouse model of coronary arteritis and determining the potential mechanisms. Methods. C57BL/6 mice were injected with Lactobacillus cell wall extract (LCWE to induce coronary arteritis. The relative levels of Resistin, TNF-α, IL-1β, and MMP-9 expression and inflammatory infiltrates in the coronary arteries were determined longitudinally by quantitative RT-PCR, ELISA, and histology. The effect of TLR4 and NF-κB activation on Resistin-induced TNF-α and IL-1β expression in human coronary artery endothelium cells (HCAECs was examined by quantitative RT-PCR. Results. Higher levels of Resistin, TNF-α, IL-1β, and MMP-9 expression were associated with the degrees of inflammatory infiltrates in the coronary artery walls of the LCWE-injected mice. Resistin enhanced TNF-α and IL-1β expression in HCAECs at 18 or 24 hours after stimulation. Pretreatment with anti-TLR4 attenuated Resistin-enhanced IL-1β, but not TNF-α, expression and pretreatment with parthenolide or QNZ demolished Resistin-enhanced TNF-α expression in HACECs. Pretreatment with parthenolide, but not QNZ, blocked Resistin-enhanced IL-1β expression in HCAECs. Conclusion. Resistin may enhance inflammation by cross-talking with TLR4/NF-κB signaling during the development of coronary arteritis in mice.

Partial deletion of eNOS gene causes hyperinsulinemic state, unbalance of cardiac insulin signaling pathways and coronary dysfunction independently of high fat diet.

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Cecilia Vecoli

Full Text Available Abnormalities in eNOS gene, possibly interacting with high fat diet (HFD, affect peripheral vascular function and glucose metabolism. The relative role of eNOS gene, HFD and metabolic derangement on coronary function has not been fully elucidated. We test whether eNOS gene deficiency per se or in association with HFD modulates coronary function through mechanisms involving molecular pathways related to insulin signaling. Wild type (WT, eNOS-/- and eNOS+/- mice were studied. WT and eNOS+/- mice were fed with either standard or HF diet for 16 weeks and compared with standard diet fed eNOS-/-. Glucose and insulin tolerance tests were performed during the last week of diet. Coronary resistance (CR was measured at baseline and during infusions of acetylcholine (Ach or sodium-nitroprusside (SNP to evaluate endothelium-dependent or independent vasodilation, in the Langendorff isolated hearts. Cardiac expression of Akt and ERK genes as evaluation of two major insulin-regulated signaling pathways involved in the control of vascular tone were assessed by western blot. HFD-fed mice developed an overt diabetic state. Conversely, chow-fed genetically modified mice (in particular eNOS-/- showed a metabolic pattern characterized by normoglycemia and hyperinsulinemia with a limited degree of insulin resistance. CR was significantly higher in animals with eNOS gene deletions than in WT, independently of diet. Percent decrease in CR, during Ach infusion, was significantly lower in both eNOS-/- and eNOS+/- mice than in WT, independently of diet. SNP reduced CR in all groups except eNOS-/-. The cardiac ERK1-2/Akt ratio, increased in animals with eNOS gene deletions compared with WT, independently of diet. These results suggest that the eNOS genetic deficiency, associated or not with HFD, has a relevant effect on coronary vascular function, possibly mediated by increase in blood insulin levels and unbalance in insulin-dependent signaling in coronary vessels

Ondas ultra-sônicas de alta freqüência causam disfunção endotelial em artérias coronárias caninas epicárdicas High-frequency ultrasonic waves cause endothelial dysfunction on canine epicardial coronary arteries

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Berent Discigil

2008-06-01

investigations. METHODS: To determine whether ultrasound energy impairs the production of nitric oxide or damages vascular smooth muscle function, isolated canine epicardial coronary artery segments were exposed to either high (25 W or low (0-10 W ultrasonic energy outputs, for 15 seconds, using an endarterectomy device prototype. After exposure, segments of epicardial coronary artery were studied in organ chambers. The following drugs were used: adenosine diphosphate (ADP, acetylcholine (Ach and sodium fluoride (NaF to study endothelium-dependent relaxation and sodium nitroprusside (SNP and isoproterenol to evaluate endothelium-independent relaxation. RESULTS: Application of high ultrasonic energy power impaired endothelium-dependent relaxation to ADP (10-9 - 10-4 M, Ach (10-9 - 10-4 M and NaF (0.5 - 9.5 mM in epicardial coronary arteries. However, low ultrasound energy output at the tip of the probe did not alter the endothelium-dependent relaxation (either maximal relaxation or EC50 to the same agonists. Vascular smooth muscle relaxation to isoproterenol (10-9 - 10-5 M or SNP (10-9 - 10-6 M was unaltered following exposure to either low or high ultrasonic energy outputs. CONCLUSION: These experiments currently prove that ultrasonic energy changes endothelial function of epicardial coronary arteries at high power. However, ultrasound does not alter the ability of vascular smooth muscle of canine epicardial coronary arteries to relax.

Short- and long-term influence of diet and simvastatin on brachial artery endothelial function

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Jensen, Lisette Okkels; Thayssen, Per; Petersen, Knud Erik

2006-01-01

BACKGROUND: Endothelium-dependent dilation (EDD) has often been studied in patients with hypercholesterolemia without overt coronary atherosclerosis where an improvement after statin treatment has been documented within few weeks. The aim of the study was to assess the short-term effect of diet...

The value of endothelium dependent vasodilatation in diagnosing coronary artery disease and its comparison with the results of routine diagnostic tests

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Ghaffari, S.; Toufan, M.

2007-01-01

To determine the predictive value of flow mediated vasodilatation (FMD) compared with angina pectoris, exercise electrocardiography and myocardial perfusion imaging (MPI). This study was carried out in Shahid Madani Heart Center, Tabriz, Iran from April 2004 to September 2006. A total of 92 patients with chest pain syndrome were enrolled in this study. Using high resolution ultrasound system endothelial function was evaluated and the result of the flow-mediated dilation (FMD %) was defined as the percent change in the internal diameter of the brachial artery during reactive hyperemia related to baseline. Coronary artery disease (CAD) was documented in 77 (83.7%) patients. The percentage of FMD was lower in patients with CAD compared with those without it (3.55 +- 3.71 versus 10.76 +- 4.61, p=0.001). In comparison with typical anginal chest pain (sensitivity 46.7%, specificity 80%) exercise stress test (sensitivity 75%, specificity 60%) and MPI (sensitivity 96.5%, specificity 55.6%) the receiver operator characteristic curve showed the percentage FMD optimal cut-off value as <= 7.41 with a sensitivity of 87.0%, specificity of 66.7%, negative predictive value of 93.0% and positive predictive value of 50%. In patients with chest pain syndrome, the FMD is a sensitive indicator of CAD with moderate specificity that is unable to predict accurately the extent and severity of it. (author)

Effect of arginase inhibition on ischemia-reperfusion injury in patients with coronary artery disease with and without diabetes mellitus.

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Oskar Kövamees

Full Text Available Arginase competes with nitric oxide synthase for their common substrate L-arginine. Up-regulation of arginase in coronary artery disease (CAD and diabetes mellitus may reduce nitric oxide bioavailability contributing to endothelial dysfunction and ischemia-reperfusion injury. Arginase inhibition reduces infarct size in animal models. Therefore the aim of the current study was to investigate if arginase inhibition protects from endothelial dysfunction induced by ischemia-reperfusion in patients with CAD with or without type 2 diabetes (NCT02009527.Male patients with CAD (n = 12 or CAD + type 2 diabetes (n = 12, were included in this cross-over study with blinded evaluation. Endothelium-dependent vasodilatation was assessed by flow-mediated dilatation (FMD of the radial artery before and after 20 min ischemia-reperfusion during intra-arterial infusion of the arginase inhibitor (Nω-hydroxy-nor-L-arginine, 0.1 mg/min or saline.The forearm ischemia-reperfusion was well tolerated. Endothelium-independent vasodilatation was assessed by sublingual nitroglycerin. Ischemia-reperfusion decreased FMD in patients with CAD from 12.7±5.2% to 7.9±4.0% during saline administration (P<0.05. Nω-hydroxy-nor-L-arginine administration prevented the decrease in FMD in the CAD group (10.3±4.3% at baseline vs. 11.5±3.6% at reperfusion. Ischemia-reperfusion did not significantly reduce FMD in patients with CAD + type 2 diabetes. However, FMD at reperfusion was higher following nor-NOHA than following saline administration in both groups (P<0.01. Endothelium-independent vasodilatation did not differ between the occasions.Inhibition of arginase protects against endothelial dysfunction caused by ischemia-reperfusion in patients with CAD. Arginase inhibition may thereby be a promising therapeutic strategy in the treatment of ischemia-reperfusion injury.

Effects of a Single Bout of Resistance Exercise in Different Volumes on Endothelium Adaptations in Healthy Animals

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Marcelo Mendonça Mota

Full Text Available Abstract Background: Resistance exercise (RE has been recommended for patients with cardiovascular diseases. Recently, a few studies have demonstrated that the intensity of a single bout of RE has an effect on endothelial adaptations to exercise. However, there is no data about the effects of different volumes of RE on endothelium function. Objective: The aim of the study was to evaluate the effects of different volumes of RE in a single bout on endothelium-dependent vasodilatation and nitric oxide (NO synthesis in the mesenteric artery of healthy animals. Methods: Male Wistar rats were divided into three groups: Control (Ct; low-volume RE (LV, 5 sets x 10 repetitions and high-volume RE (HV, 15 sets x 10 repetitions. The established intensity was 70% of the maximal repetition test. After the exercise protocol, rings of mesenteric artery were used for assessment of vascular reactivity, and other mesenteric arteries were prepared for detection of measure NO production by DAF-FM fluorescence. Insulin responsiveness on NO synthesis was evaluated by stimulating the vascular rings with insulin (10 nM. Results: The maximal relaxation response to insulin increased in the HV group only as compared with the Ct group. Moreover, the inhibition of nitric oxide synthesis (L-NAME completely abolished the insulin-induced vasorelaxation in exercised rats. NO production showed a volume-dependent increase in the endothelial and smooth muscle layer. In endothelial layer, only Ct and LV groups showed a significant increase in NO synthesis when compared to their respective group under basal condition. On the other hand, in smooth muscle layer, NO fluorescence increased in all groups when compared to their respective group under basal condition. Conclusions: Our results suggest that a single bout of RE promotes vascular endothelium changes in a volume-dependent manner. The 15 sets x 10 repetitions exercise plan induced the greatest levels of NO synthesis.

Beer elicits vasculoprotective effects through Akt/eNOS activation.

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Vilahur, Gemma; Casani, Laura; Mendieta, Guiomar; Lamuela-Raventos, Rosa M; Estruch, Ramon; Badimon, Lina

2014-12-01

There is controversy regarding the effect of alcohol beverage intake in vascular vasodilatory function in peripheral arteries. The effects of beer intake in coronary vasodilation remain unknown. We investigated whether regular beer intake (alcohol and alcohol-free) protects against hypercholesterolaemia-induced coronary endothelial dysfunction and the mechanisms behind this effect. Pigs were fed 10 days: (i) a Western-type hypercholesterolaemic diet (WD); (ii) WD+low-dose beer (12·5 g alcohol/day); (iii) WD+moderate-dose beer (25 g alcohol/day); or (iv) WD+moderate-dose alcohol-free-beer (0·0 g alcohol/day). Coronary responses to endothelium-dependent vasoactive drugs (acetylcholine: receptor mediated; calcium ionophore-A23189: nonreceptor mediated), endothelium-independent vasoactive drug (SNP) and L-NMMA (NOS-antagonist) were evaluated in the LAD coronary artery by flow Doppler. Coronary Akt/eNOS activation, MCP-1 expression, oxidative DNA damage and superoxide production were assessed. Lipid profile, lipoproteins resistance to oxidation and urinary isoxanthohumol concentration were evaluated. Alcoholic and nonalcoholic beer intake prevented WD-induced impairment of receptor- and non-receptor-operated endothelial-dependent coronary vasodilation. All animals displayed a similar vasodilatory response to SNP and L-NMMA blunted all endothelial-dependent vasorelaxation responses. Haemodynamic parameters remained unchanged. Coronary arteries showed lower DNA damage and increased Akt/eNOS axis activation in beer-fed animals. Animals taking beer showed HDL with higher antioxidant capacity, higher LDL resistance to oxidation and increased isoxanthohumol levels. Weight, lipids levels, liver enzymes and MCP-1 expression were not affected by beer intake. Non-alcoholic-related beer components protect against hyperlipemia-induced coronary endothelial dysfunction by counteracting vascular oxidative damage and preserving the Akt/eNOS pathway. Light-to-moderate beer

Targeted Delivery of Neutralizing Anti-C5 Antibody to Renal Endothelium Prevents Complement-Dependent Tissue Damage

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Paolo Durigutto

2017-09-01

Full Text Available Complement activation is largely implicated in the pathogenesis of several clinical conditions and its therapeutic neutralization has proven effective in preventing tissue and organ damage. A problem that still needs to be solved in the therapeutic control of complement-mediated diseases is how to avoid side effects associated with chronic neutralization of the complement system, in particular, the increased risk of infections. We addressed this issue developing a strategy based on the preferential delivery of a C5 complement inhibitor to the organ involved in the pathologic process. To this end, we generated Ergidina, a neutralizing recombinant anti-C5 human antibody coupled with a cyclic-RGD peptide, with a distinctive homing property for ischemic endothelial cells and effective in controlling tissue damage in a rat model of renal ischemia/reperfusion injury (IRI. As a result of its preferential localization on renal endothelium, the molecule induced complete inhibition of complement activation at tissue level, and local protection from complement-mediated tissue damage without affecting circulating C5. The ex vivo binding of Ergidina to surgically removed kidney exposed to cold ischemia supports its therapeutic use to prevent posttransplant IRI leading to delay of graft function. Moreover, the finding that the ex vivo binding of Ergidina was not restricted to the kidney, but was also seen on ischemic heart, suggests that this RGD-targeted anti-C5 antibody may represent a useful tool to treat organs prior to transplantation. Based on this evidence, we propose preliminary data showing that Ergidina is a novel targeted drug to prevent complement activation on the endothelium of ischemic kidney.

Enhanced K+-channel-mediated endothelium-dependent local and conducted dilation of small mesenteric arteries from ApoE−/− mice

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Beleznai, Timea; Takano, Hiromichi; Hamill, Claire; Yarova, Polina; Douglas, Gillian; Channon, Keith; Dora, Kim

2011-01-01

Aims Agonists that evoke smooth muscle cell hyperpolarization have the potential to stimulate both local and conducted dilation. We investigated whether the endothelium-dependent vasodilators acetylcholine (ACh) and SLIGRL stimulated conducted dilation and whether this was altered by deficiency in apolipoprotein E (ApoE−/−). Methods and results Isolated mesenteric arteries were cannulated, pressurized, and precontracted with phenylephrine. Agonists were either added to the bath to study local dilation or were restricted to one end of arteries to study conducted dilation. An enhanced sensitivity to both ACh and SLIGRL was observed in mesenteric arteries from ApoE−/− mice compared with wild-type controls. Inhibition of nitric oxide (NO) synthase blocked ACh responses, but had no effect on maximum dilation to SLIGRL. SLIGRL increased endothelial cell Ca2+, hyperpolarized smooth muscle cells, and fully dilated arteries. The NO-independent dilation to SLIGRL was blocked with high [KCl] or Ca2+-activated K+-channel blockers. The hyperpolarization and dilation to SLIGRL passed through the artery to at least 2.5 mm upstream. The conducted dilation was not affected by a deficit in ApoE and could also be stimulated by ACh, suggesting NO itself could stimulate conducted dilation. Conclusion In small mesenteric arteries of ApoE−/− mice, NO-independent dilation is enhanced. Since both NO-dependent and -independent pathways can stimulate local and conducted dilation, the potential for reducing vascular resistance is improved in these vessels. PMID:21690174

Biased activity of soluble guanylyl cyclase: the Janus face of thymoquinone.

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Detremmerie, Charlotte; Vanhoutte, Paul M; Leung, Susan

2017-07-01

The natural compound thymoquinone, extracted from Nigella sativa (black cumin), is widely used in humans for its anti-oxidative properties. Thymoquinone is known for its acute endothelium-independent vasodilator effects in isolated rat aortae and pulmonary arteries, depending in part on activation of adenosine triphosphate-sensitive potassium channels and inhibition of voltage-dependent calcium channels. The compound also improves endothelial dysfunction in mesenteric arteries of ageing rodents and in aortae of rabbits treated with pyrogallol, by inhibiting oxidative stress. Serendipitously, thymoquinone was found to augment contractions in isolated arteries with endothelium of both rats and pigs. The endothelium-dependent augmentation it causes counterintuitively depends on biased activation of soluble guanylyl cyclase (sGC) producing inosine 3',5'-cyclic monophosphate (cyclic IMP) rather than guanosine 3',5'-cyclic monophosphate. This phenomenon shows a striking mechanistic similarity to the hypoxic augmentation previously observed in porcine coronary arteries. The cyclic IMP preferentially produced under thymoquinone exposure causes an increased contractility of arterial smooth muscle by interfering with calcium homeostasis. This brief review summarizes the vascular pharmacology of thymoquinone, focussing in particular on how the compound causes endothelium-dependent contractions by biasing the activity of sGC.

Flow-mediated dilatation has no independent prognostic effect in patients with chest pain with or without ischaemic heart disease

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Ulriksen, Line Skjold; Malmqvist, Beata B; Hansen, Are

2009-01-01

OBJECTIVE: The purpose of this study was to assess the prognostic effect of flow-mediated dilatation (FMD) in patients with chest pain admitted to a coronary care unit. METHODS: Endothelium-dependent FMD in the brachial artery was examined in 223 patients with acute chest pain. All patients...... underwent a stress test at the time of admittance. On the basis of a positive stress test, a prior myocardial infarction (MI), prior percutaneous coronary intervention (PCI) or coronary bypass surgery (CABG), 137 patients were categorized as having ischaemic heart disease (IHD). RESULTS: Patients with IHD...

Human haemato-endothelial precursors: cord blood CD34+ cells produce haemogenic endothelium.

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Elvira Pelosi

Full Text Available Embryologic and genetic evidence suggest a common origin of haematopoietic and endothelial lineages. In the murine embryo, recent studies indicate the presence of haemogenic endothelium and of a common haemato-endothelial precursor, the haemangioblast. Conversely, so far, little evidence supports the presence of haemogenic endothelium and haemangioblasts in later stages of development. Our studies indicate that human cord blood haematopoietic progenitors (CD34+45+144-, triggered by murine hepatocyte conditioned medium, differentiate into adherent proliferating endothelial precursors (CD144+CD105+CD146+CD31+CD45- capable of functioning as haemogenic endothelium. These cells, proven to give rise to functional vasculature in vivo, if further instructed by haematopoietic growth factors, first switch to transitional CD144+45+ cells and then to haematopoietic cells. These results highlight the plasticity of haemato-endhothelial precursors in human post-natal life. Furthermore, these studies may provide highly enriched populations of human post-fetal haemogenic endothelium, paving the way for innovative projects at a basic and possibly clinical level.

Evaluation of the restenosis of coronary artery after percutaneous transluminal coronary angioplasty by three-dimensional coronary magnetic resonance angiography

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Arisaka, Hiraku

2000-01-01

Coronary magnetic resonance angiography (MRA) has been recently brought into clinical use, however, there has not been reports on the comparison with MRA and conventional contrast coronary angiography (CAG) in the detection of the localization and characteristics of coronary restenosis after percutaneous transluminal coronary angioplasty (PTCA). To assess the restenosis of coronary artery after PTCA, this study compared three-dimensional (3D) coronary MRA and CAG. One hundred three patients (76 males and 27 females, average age of 64.6±9.3 years old) were performed coronary MRA at 3-6 months after PTCA. The right coronary artery (RCA) group consist of 21 patients, the left anterior descending branch (LAD) 63 patients and the left circumflex branch (LCX) 19 patients. Coronary MRA was performed with the patients in supine position on a 1.5 T whole body scanner (MAGNETOM VISION, Siemens AG, Germany) using body array coil. The imaging technique used a 3-D gradient echo sequence with respiratory gating and fat suppression. The slice thickness was 2 mm, slab thickness 32 mm, a field of view of 300 mm and a matrix of 128 x 256. Other parameters were an echo time of 2.7 ms and a repetition time of 600 to 1100 msec. The measurement time of 1 imaging slab took 15 to 20 minutes depending on the patient's heart rate. The coronary arteries were reconstructed from the 3-D data set using a multiplanar reconstruction (MPR) technique. According to previous coronary MRA studies, a significant stenosis with a luminal reduction of ≥50% was assumed if a marked signal reduction or signal loss of a vessel segment was visible. In CAG, 57 of 103 patients showed restenosis. In coronary MRA, 37 of 103 patients demonstrated restenosis. The sensitivity, specificity, positive and negative predictive values were 64.9%, 100%, 100% and 69.6%, respectively. Predictive accuracy was 79.6%. Three-dimensional coronary MRA is useful in a noninvasive diagnostic method to evaluate the coronary

Evaluation of combined intracoronary two-dimensional and doppler ultransound techniques in the relaxation function of coronary microcirculation

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Qi Chunmei; Li Dongye; Pan Defeng; Zhu Hong

2005-01-01

Objective: To observe the value of detecting the relaxation function of coronary microcirculation by using combined intracoronary two-dimensional (IVUS) and Doppler interventional ultransound (ICD) techniques with mean arteries pressure. Methods: Fourteen healthy male swines were divided into two groups randomly: eight swines fed with 1% cholesterol-rich diet for 12 weeks as a model of early atherosclerosis were classified as the experimental group; six swines fed with standard diet were classified as control group. All the swines were undergone cardiovascular catheterization examination after 12 weeks. Combined IVUS and ICD techniques were taken to calculate the change of coronary blood flow (CBF) after the administration of acetylcholine and nitroglycerin. The pressure of the root of aorta and then the relaxation function of coronary microcirculation can be accessed with coronary resistance index (RI). At last, all of the examed coronary arteries and related coronary microcirculation were undergone pathological examinations. Results: The pathological examinations demonstrated that the average intima thickness in experimental group was increased more evidently than that of control group (74.80 μm ± 17.60 μm vs 7.60 μm ± 4.27 μm P<0.001). The intima thickness increase can not be seen in the coronary microcirculation. Acetylcholine induced increase in RI in experimental group compared with control group (-0.18 ± 0.09 vs 0.29 ± 0.18, P<0.05). Nitroglycerin induced a decrease in RI for both groups (-0.40 ± 0.13 vs -0.34 ± 0.20). Conclusions: Using IVUS and ICD techniques combined mean arterial pressure can identify the endothelium-mediated dysfunction on coronary microcirculation in the early stage of AS. (authors)

Spinal anesthesia reduces postoperative delirium in opium dependent patients undergoing coronary artery bypass grafting.

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Tabatabaie, O; Matin, N; Heidari, A; Tabatabaie, A; Hadaegh, A; Yazdanynejad, S; Tabatabaie, K

2015-01-01

We investigated the effect of high spinal anesthesia on postoperative delirium in opium dependent patients undergoing coronary artery bypass grafting (CABG). The study was conducted in a tertiary referral university hospital on a population of 60 opium dependent patients undergoing CABG surgery. Patients were divided into two groups based on anesthesia protocol. One group were given general anesthesia (GA Group), the other group additionally received intrathecal morphine and bupivacaine (SGA Group). Postoperative delirium (POD) was defined as the main outcome of interest. Incidence of POD was significantly higher in patients of GA Group as compared with those in SGA Group (47% and 17% for GA and SGA respectively; P-value = 0.01). Time to extubation was on average 2.2 h shorter in SGA than in GA (7.1 h and 9.3 h respectively, P-value opium dependent patients.

Circulating microparticles from patients with valvular heart disease and cardiac surgery inhibit endothelium-dependent vasodilation.

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Fu, Li; Hu, Xiao-Xia; Lin, Ze-Bang; Chang, Feng-Jun; Ou, Zhi-Jun; Wang, Zhi-Ping; Ou, Jing-Song

2015-09-01

Vascular function is very important for maintaining circulation after cardiac surgery. Circulating microparticles (MPs) generated in various diseases play important roles in causing inflammation, coagulation, and vascular injury. However, the impact of MPs generated from patients who have valvular heart disease (VHD), before and after cardiac surgery, on vascular function remains unknown. This study is designed to investigate the impact of such MPs on vasodilation. Microparticles were isolated from age-matched healthy subjects and patients who had VHD, before cardiac surgery, and at 12 hours and 72 hours afterward. The number of MPs was measured and compared. Effects evaluated were of the impact of MPs on: vasodilation of mice aorta; the phosphorylation and expression of Akt, endothelial nitric oxide synthase (eNOS), protein kinase C-βII (PKC-βII), and p70 ribosomal protein S6 kinase (p70S6K); expression of caveolin-1; the association of eNOS with heat shock protein 90 (HSP90); and generation of nitric oxide and superoxide anion of human umbilical vein endothelial cells. Compared with the healthy subjects, VHD patients had significantly higher levels of circulating MPs and those MPs before cardiac surgery can: impair endothelium-dependent vasodilation; inhibit phosphorylation of Akt and eNOS; increase activation of PKC-βII and p70S6K; enhance expression of caveolin-1; reduce the association of HSP90 with eNOS; decrease nitric oxide production, and increase superoxide anion generation. These deleterious effects were even stronger in postoperative MPs. Our data demonstrate that MPs generated from VHD patients before and after cardiac surgery contributed to endothelial dysfunction, by uncoupling and inhibiting eNOS. Circulating MPs are potential therapeutic targets for the maintenance of vascular function postoperatively. Copyright © 2015 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.

Monoclonal antibody PAL-E specific for endothelium

NARCIS (Netherlands)

Schlingemann, R. O.; Dingjan, G. M.; Emeis, J. J.; Blok, J.; Warnaar, S. O.; Ruiter, D. J.

1985-01-01

A monoclonal antibody, PAL-E, is described that is specific for endothelial cells. The monoclonal antibody, an IgG2a, markedly stains endothelium of capillaries, medium-sized and small veins, and venules in frozen sections of human and some animal tissues tested. It reacts not at all or only weakly

Coronary Flow Reserve Predicts Cardiopulmonary Fitness in Patients with Coronary Artery Disease Independently of Systolic and Diastolic Function

DEFF Research Database (Denmark)

Snoer, Martin; Olsen, Rasmus Huan; Monk-Hansen, Tea

2014-01-01

Aims Despite revascularization and optimal medical treatment, patients with coronary artery disease (CAD) have reduced exercise capacity. In the absence of coronary artery stenosis, coronary flow reserve (CFR) is a measure of coronary microvascular function, and a marker of future poor outcome...... in CAD patients. The aim of this study was to examine the relationship among CFR, systolic and diastolic function, peripheral vascular function, and cardiopulmonary fitness in CAD patients. Methods and Results Forty patients with median left ventricular ejection fraction (LVEF) 49 (interquartile 46....... Conclusions Coronary flow reserve measured noninvasively predicts cardiopulmonary fitness independently of resting systolic and diastolic function in CAD patients, indicating that cardiac output during maximal exercise is dependent on the ability of the coronary circulation to adapt to the higher metabolic...

Biased activity of soluble guanylyl cyclase: the Janus face of thymoquinone

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Charlotte Detremmerie

2017-07-01

Full Text Available The natural compound thymoquinone, extracted from Nigella sativa (black cumin, is widely used in humans for its anti-oxidative properties. Thymoquinone is known for its acute endothelium-independent vasodilator effects in isolated rat aortae and pulmonary arteries, depending in part on activation of adenosine triphosphate-sensitive potassium channels and inhibition of voltage-dependent calcium channels. The compound also improves endothelial dysfunction in mesenteric arteries of ageing rodents and in aortae of rabbits treated with pyrogallol, by inhibiting oxidative stress. Serendipitously, thymoquinone was found to augment contractions in isolated arteries with endothelium of both rats and pigs. The endothelium-dependent augmentation it causes counterintuitively depends on biased activation of soluble guanylyl cyclase (sGC producing inosine 3ʹ,5ʹ-cyclic monophosphate (cyclic IMP rather than guanosine 3ʹ,5ʹ-cyclic monophosphate. This phenomenon shows a striking mechanistic similarity to the hypoxic augmentation previously observed in porcine coronary arteries. The cyclic IMP preferentially produced under thymoquinone exposure causes an increased contractility of arterial smooth muscle by interfering with calcium homeostasis. This brief review summarizes the vascular pharmacology of thymoquinone, focussing in particular on how the compound causes endothelium-dependent contractions by biasing the activity of sGC.

Consequences of PAI-1 specific deletion in endothelium on radiation-induced intestinal damage

International Nuclear Information System (INIS)

Rannou, Emilie

2015-01-01

Radiation-induced injury to healthy tissues is a real public health problem, since they are one of the most limiting factors that restrict efficiency of radiation therapy. This problematic is also part of the French Cancer Plan 2014-2017, and involves clinical research. Concepts surrounding the development of radiation-induced damage have gradually evolved into a contemporary and integrated view of the pathogenesis, involving all compartments of target tissue. Among them, endothelium seems to be central in the sequence of interrelated events that lead to the development of radiation-induced damage, although there are rare concrete elements that support this concept. By using new transgenic mouse models, this PhD project provides a direct demonstration of an endothelium-dependent continuum in evolution of radiation-induced intestinal damage. Indeed, changes in the endothelial phenotype through targeted deletion of the gene SERPINE1, chosen because of its key role in the development of radiation enteritis, influences various parameters of the development of the disease. Thus, lack of PAI-1 secretion by endothelial cells significantly improves survival of the animals, and limits severity of early and late tissue damage after a localized small bowel irradiation. Furthermore, these mice partially KO for PAI-1 showed a decrease in the number of apoptotic intestinal stem cells in the hours following irradiation, a decrease in the macrophages infiltrate density one week after irradiation, and a change in the polarization of macrophages throughout the pathophysiological process. In an effort to protect healthy tissues from radiation therapy side effects, without hindering the cancer treatment, PAI-1 seems to be an obvious therapeutic target. Conceptually, this work represents the direct demonstration of the link between endothelium phenotype and radiation enteritis pathogenesis. (author)

Hemodynamics, functional state of endothelium and renal function, platelets depending on the body mass index in patients with chronic heart failure and preserved systolic function

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Kushnir Yu.

2014-03-01

Full Text Available The aim of the study was to evaluate hemodynamics, endothelium function of kidneys and platelets depending on the body mass index (BMI in patients with chronic heart failure (CHF and preserved systolic function. 42 patients (mean age - 76,690,83 years with CHF II-III FC NYHA with preserved systolic function (LVEF>45% were enrolled. Echocardiography was performed, endothelial function, serum creatinine levels and microalbuminuria were determined in patients. BMI and glomerulation filtration rate were calculated by formulas. The morphological and functional status of platelets was estimated by electronic microscopy. It was defined that increased BMI in patients with CHF and preserved systolic function determines the structural and functional changes of the myocardium and leads to the endothelial and renal functional changes. An increased risk of thrombogenesis was established in patients with overweight and obesity.

Measurement of coronary flow response to cold pressor stress in asymptomatic women with cardiovascular risk factors using spiral velocity-encoded cine MRI at 3 Tesla

International Nuclear Information System (INIS)

Maroules, Christopher D.; Peshock, Ronald M.; Chang, Alice Y.; Kontak, Andrew; Dimitrov, Ivan; Kotys, Melanie

2010-01-01

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 CS flow response because it elicits an endothelium-dependent coronary vasodilation that may afford greater sensitivity for detecting early changes in coronary endothelial function. Purpose: To investigate the feasibility and reproducibility of CS flow reactivity (CSFR) to CPT using spiral VEC MRI at 3 Tesla in a sample of asymptomatic women with cardiovascular risk factors. Material and Methods: Fourteen asymptomatic women (age 38 years ± 10) with cardiovascular risk factors were studied using 3D spiral VEC MRI of the CS at 3 T. The CPT was utilized as a provocative stress to measure changes in CS flow. CSFR to CPT was calculated from the ratio of CS flow during peak stress to baseline CS flow. Results: CPT induced a significant hemodynamic response as measured by a 45% increase in rate-pressure product (P<0.01). A significant increase in CS volume flow was also observed (baseline, 116 ± 26 ml/min; peak stress, 152 ± 34 ml/min, P=0.01). CSFR to CPT was 1.31 ± 0.20. Test-retest variability of CS volume flow was 5% at baseline and 6% during peak stress. Conclusion: Spiral CS VEC MRI at 3 T is a feasible and reproducible technique for measuring CS flow in asymptomatic women at risk for cardiovascular disease. Significant changes in CSFR to CPT are detectable, without demanding pharmacologic stress

Helium induces preconditioning in human endothelium in vivo

NARCIS (Netherlands)

Smit, Kirsten F.; Oei, Gezina T. M. L.; Brevoord, Daniel; Stroes, Erik S.; Nieuwland, Rienk; Schlack, Wolfgang S.; Hollmann, Markus W.; Weber, Nina C.; Preckel, Benedikt

2013-01-01

Helium protects myocardium by inducing preconditioning in animals. We investigated whether human endothelium is preconditioned by helium inhalation in vivo. Forearm ischemia-reperfusion (I/R) in healthy volunteers (each group n = 10) was performed by inflating a blood pressure cuff for 20 min.

HIF-1α Deletion in the Endothelium, but Not in the Epithelium, Protects From Radiation-Induced Enteritis

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Aurore Toullec

2018-01-01

Conclusions: We demonstrate in vivo that HIF-1α impacts radiation-induced enteritis and that this role differs according to the targeted cell type. Our work provides a new role for HIF-1α and endothelium-dependent mechanisms driving inflammatory processes in gut mucosae. Results presented show that effects on normal tissues have to be taken into account in approaches aiming to modulate hypoxia or hypoxia-related molecular mechanisms.

The Effects of Creatine Monohydrate on Permeability of Coronary Artery Endothelium and Level of Blood Lipoprotein in Diabetic Rats.

Science.gov (United States)

Rahmani, Asghar; Asadollahi, Khairollah; Soleimannejad, Kourosh; Khalighi, Zahra; Mohsenzadeh, Yosouf; Hemati, Ruhollah; Moradkhani, Atefeh; Abangah, Ghobad

2016-09-01

Creatine monohydrate has beneficial effects on serum glucose. This study aimed to investigate the effects of creatine on serum biochemical markers and permeability of coronary arteries among diabetic rats. 32 Wistar rats, which weighed 150-200 grams were randomly divided into 4 groups including: group I, control; group II, creatine monohydrate; group III, diabetic rats; and group IV, diabetic rats + creatine. Creatine monohydrate was applied by 400 mg/kg/daily for 5 months. Animals' weights and blood samples were taken before and after the study. Endothelial permeability rate was measured by Evans Blue method. Data were analysed by SPSS 16. At the end of fifth month, rats' weights in diabetic group under treatment with creatine, compared to those without, increased significantly (pcreatine (pcreatine compared to untreated groups, closed to the intact group (pcreatine monohydrate caused an improvement of serum biochemical markers associated with diabetes and reduced the permeability rate of coronary arteries among diabetic rats. © 2016 by the Association of Clinical Scientists, Inc.

Variation in the sodium-dependent vitamin C transporter 2 gene is associated with risk of acute coronary syndrome among women.

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Christine Dalgård

Full Text Available BACKGROUND: Vitamin C is associated with a lower risk of coronary heart disease possibly due to its anti-oxidative effects, beneficial effects on endothelial function and importance in collagen synthesis. The sodium-dependent vitamin C transporter 2 is responsible for the transport of vitamin C into various cells and malfunction of this protein leads to reduced vitamin C in tissue, including the arterial wall. We tested the hypothesis that candidate variations rs6139591 and rs1776964 in the gene coding for sodium-dependent vitamin C transporter 2 are associated with development of acute coronary syndrome. DESIGN: In the Danish Diet, Cancer and Health cohort study, we performed a case-cohort study among 57,053 subjects aged 50-64 years. RESULTS: During a mean follow-up period of 6.4 years, we identified 936 cases and randomly selected a sub-cohort (n = 1,580 with full information on genotypes and covariates. Using Cox proportional hazard models, we found that women with the rs6139591 TT genotype and a lower than median dietary vitamin C intake had a higher risk of acute coronary syndrome compared with those with the CC genotype (adjusted HR 5.39, 95% confidence interval, 2.01-14.50. We also observed a not as strong but positive although inconsistent association for women at a higher than median intake of vitamin C rich food. For the rs1776964 polymorphism, we found a higher risk (adjusted HR 3.45, 95% CI, 1.16-10.28 among TT-homozygous women with higher than median vitamin C intake compared with the CC genotype and low vitamin C intake. Among men, weaker and non-significant associations were observed for both polymorphisms. CONCLUSION: Genetic variation in the sodium-dependent vitamin C transporter 2 is associated with risk of incident acute coronary syndrome in women. The genotype effects may not be fully compensated by a higher intake of vitamin C rich food.

Efeito dos ácidos graxos ômega-3 sobre o relaxamento-dependente do endotélio em coelhos hipercolesterolêmicos Effects of omega-3 fatty acids on endothelium-dependent relaxation in hypercholesterolemic rabbits

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Paulo Afonso Ribeiro Jorge

1997-07-01

Full Text Available OBJETIVO: Estudar o efeito dos ácidos graxos ômega-3 sobre o relaxamento-dependente do endotélio, o colesterol plasmático, as LDL, VLDL, HDL, triglicérides e a peroxidação lipídica das partículas de LDL-nativas, oxidadas e da parede arterial. MÉTODOS: Coelhos da raça Nova Zelândia foram submetidos a dieta enriquecida com colesterol (0,5% e gordura de coco (2%, por 30 dias e separados em grupo hipercolesterolemia (H e ômega-3 (O-3, sendo administrado ao O-3 ácidos graxos ômega-3 na dose de 300mg/kg/dia, durante 15 dias, através de gavagem. O colesterol plasmático, triglicérides, LDL-colesterol, VLDL e HDL-colesterol foram medidos através de kits enzimáticos e os resultados expressos em mg/dl. As LDL foram obtidas por ultracentrifugação e oxidadas através da exposição ao Cu++. A peroxidação lipídica das LDL e da parede da aorta foi mensurada pela dosagem do malondialdeido (MDA. A função endotelial foi avaliada por curvas de concentração-efeito obtidas pela acetilcolina e nitroprussiato, após contração com norepinefrina. RESULTADOS: Houve aumento do colesterol plasmático e das VLDL, sem interferência nos níveis de LDL e HDL, no O-3. Observou-se redução significante dos triglicérides. Verificou-se aumento significante do teor de MDA nas LDL-nativas e oxidadas, assim como na parede arterial. O relaxamento-dependente do endotélio foi significativamente menor no O-3. CONCLUSÃO: A administração de ácidos graxos ômega-3 na dosagem de 300/mg/kg/dia, a coelhos hipercolesterolêmicos aumentou o colesterol e as VLDL plasmáticas, enquanto reduziu os triglicérides. O relaxamento-dependente do endotélio foi menor que no grupo H.PURPOSE: To study the effect of omega-3 fatty acid on endothelium-dependent relaxation, total plasma cholesterol, LDL-cholesterol, HDL-cholesterol and triglycerides levels as well as, the malondialdehyde (MDA content of the LDL particles and arterial wall. METHODS: Fourteen male rabbits

Rat Liver Enzyme Release Depends on Blood Flow-Bearing Physical Forces Acting in Endothelium Glycocalyx rather than on Liver Damage

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Julieta A. Díaz-Juárez

2017-01-01

Full Text Available We have found selective elevation of serum enzyme activities in rats subjected to partial hepatectomy (PH, apparently controlled by hemodynamic flow-bearing physical forces. Here, we assess the involvement of stretch-sensitive calcium channels and calcium mobilization in isolated livers, after chemical modifications of the endothelial glycocalyx and changing perfusion directionality. Inhibiting in vivo protein synthesis, we found that liver enzyme release is influenced by de novo synthesis of endothelial glycocalyx components, and released enzymes are confined into a liver “pool.” Moreover, liver enzyme release depended on extracellular calcium entry possibly mediated by stretch-sensitive calcium channels, and this endothelial-mediated mechanotransduction in liver enzyme release was also evidenced by modifying the glycocalyx carbohydrate components, directionality of perfusing flow rate, and the participation of nitric oxide (NO and malondialdehyde (MDA, leading to modifications in the intracellular distribution of these enzymes mainly as nuclear enrichment of “mitochondrial” enzymes. In conclusion, the flow-induced shear stress may provide fine-tuned control of released hepatic enzymes through mediation by the endothelium glycocalyx, which provides evidence of a biological role of the enzyme release rather to be merely a biomarker for evaluating hepatotoxicity and liver damage, actually positively influencing progression of liver regeneration in mammals.

Dependence of intramyocardial pressure and coronary flow on ventricular loading and contractility: a model study.

Science.gov (United States)

Bovendeerd, Peter H M; Borsje, Petra; Arts, Theo; van De Vosse, Frans N

2006-12-01

The phasic coronary arterial inflow during the normal cardiac cycle has been explained with simple (waterfall, intramyocardial pump) models, emphasizing the role of ventricular pressure. To explain changes in isovolumic and low afterload beats, these models were extended with the effect of three-dimensional wall stress, nonlinear characteristics of the coronary bed, and extravascular fluid exchange. With the associated increase in the number of model parameters, a detailed parameter sensitivity analysis has become difficult. Therefore we investigated the primary relations between ventricular pressure and volume, wall stress, intramyocardial pressure and coronary blood flow, with a mathematical model with a limited number of parameters. The model replicates several experimental observations: the phasic character of coronary inflow is virtually independent of maximum ventricular pressure, the amplitude of the coronary flow signal varies about proportionally with cardiac contractility, and intramyocardial pressure in the ventricular wall may exceed ventricular pressure. A parameter sensitivity analysis shows that the normalized amplitude of coronary inflow is mainly determined by contractility, reflected in ventricular pressure and, at low ventricular volumes, radial wall stress. Normalized flow amplitude is less sensitive to myocardial coronary compliance and resistance, and to the relation between active fiber stress, time, and sarcomere shortening velocity.

Gastrin-releasing peptide induces monocyte adhesion to vascular endothelium by upregulating endothelial adhesion molecules

International Nuclear Information System (INIS)

Kim, Mi-Kyoung; Park, Hyun-Joo; Kim, Yeon; Kim, Hyung Joon; Bae, Soo-Kyung; Bae, Moon-Kyoung

2017-01-01

Gastrin-releasing peptide (GRP) is a neuropeptide that plays roles in various pathophysiological conditions including inflammatory diseases in peripheral tissues; however, little is known about whether GRP can directly regulate endothelial inflammatory processes. In this study, we showed that GRP promotes the adhesion of leukocytes to human umbilical vein endothelial cells (HUVECs) and the aortic endothelium. GRP increased the expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) by activating nuclear factor-κB (NF-κB) in endothelial cells. In addition, GRP activated extracellular signal-regulated kinase 1/2 (ERK1/2), p38MAPK, and AKT, and the inhibition of these signaling pathways significantly reduced GRP-induced monocyte adhesion to the endothelium. Overall, our results suggested that GRP may cause endothelial dysfunction, which could be of particular relevance in the development of vascular inflammatory disorders. - Highlights: • GRP induces adhesion of monocytes to vascular endothelium. • GRP increases the expression of endothelial adhesion molecules through the activation of NF-κB. • ERK1/2, p38MAPK, and Akt pathways are involved in the GRP-induced leukocyte adhesiveness to endothelium.

Binding of human endothelium to Ulex europaeus I-coated Dynabeads: application to the isolation of microvascular endothelium.

Science.gov (United States)

Jackson, C J; Garbett, P K; Nissen, B; Schrieber, L

1990-06-01

A major problem encountered when isolating human microvascular endothelium is the presence of contaminating cells such as fibroblasts that rapidly over-grow the endothelial cells. We describe here a simple, rapid technique for purifying endothelial cells derived from the microvasculature of neonatal foreskin and osteoarthritic and rheumatoid arthritic synovium. This technique is based on the selective binding of the lectin Ulex europaeus I (UEA I) to the endothelial cell surface via fucose residues. Initially UEA I was covalently bound to tosyl-activated super-paramagnetic polystyrene beads (Dynabeads) by incubation for 24 h at room temperature. Cells were isolated by extracting microvascular segments from enzyme-treated (trypsin and Pronase) cubes of tissue. The mixed population of cells obtained were purified by incubating them at 4 degrees C for 10 min with the UEA I-coated Dynabeads. Endothelium bound to the beads whilst contaminating cells were removed by five washes with HBSS using a magnetic particle concentrator. The endothelial cells thus obtained grew to confluence as a cobblestone-like monolayer and expressed von Willebrand factor antigen. The cells were released from the Dynabeads by the competitive binding of fucose (10 min at 4 degrees C). This new method is simple and reproducible and allows pure human microvascular endothelial cells to be cultured within 2 h of obtaining a specimen.

Sevoflurane mitigates shedding of hyaluronan from the coronary endothelium, also during ischemia/reperfusion: an ex vivo animal study

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Chen C

2016-04-01

Full Text Available Congcong Chen,1,3 Daniel Chappell,2,3 Thorsten Annecke,2,3 Peter Conzen,2 Matthias Jacob,2,3 Ulrich Welsch,4 Bernhard Zwissler,2 Bernhard F Becker3 1Department of Anesthesiology, Second Affiliated Hospital of Zhejiang University, Hangzhou, People's Republic of China; 2Clinic of Anesthesiology, Ludwig-Maximilians-University, Munich, Germany; 3Walter-Brendel-Centre of Experimental Medicine, Ludwig-Maximilians-University, Munich, Germany; 4Institute of Anatomy, Ludwig-Maximilians-University, Munich, Germany Abstract: Glycosaminoglycan hyaluronan (HA, a major constituent of the endothelial glycocalyx, helps to maintain vascular integrity. Preconditioning the heart with volatile anesthetic agents protects against ischemia/reperfusion injury. We investigated a possible protective effect of sevoflurane on the glycocalyx, especially on HA. The effect of pre-ischemic treatment with sevoflurane (15 minutes at 2% vol/vol gas on shedding of HA was evaluated in 28 isolated, beating guinea pig hearts, subjected to warm ischemia (20 minutes at 37°C followed by reperfusion (40 minutes, half with and half without preconditioning by sevoflurane. HA concentration was measured in the coronary effluent. Over the last 20 minutes of reperfusion hydroxyethyl starch (1 g% was continuously infused and the epicardial transudate collected over the last 5 minutes for measuring the colloid extravasation. Additional hearts were fixed by perfusion after the end of reperfusion for immunohistology and electron microscopy. Sevoflurane did not significantly affect post-ischemic oxidative stress, but strongly inhibited shedding of HA during the whole period, surprisingly even prior to ischemia. Immunohistology demonstrated that heparan sulfates and SDC1 of the glycocalyx were also preserved by sevoflurane. Electron microscopy revealed shedding of glycocalyx caused by ischemia and a mostly intact glycocalyx in hearts exposed to sevoflurane. Coronary vascular permeability of the

Ultrastructure of endothelium in ovules of Penstemon gentianoides Poir. (Scrophulariaceae) at mature embryo sac phase.

Science.gov (United States)

Dane, Feruzan; Olgun, Göksel; Ekici, Nuran

2007-06-01

In this study ultrastructural differences between endothelial cells of different location in Penstemon gentianoides have been examined with electron microscope at mature embryo sac phase. Embryo sac is of the Polygonum type and surrounded by endothelium except the micropylar region. The cuticle is located primarily around the chalazal three-fourths of the embryo sac. Endothelium cells around the chalaza and toward the micropylar region are rich in cytoplasmic organelles. The cytoplasm of endothelial cells near the central cell has large vacuoles and few organelles. There are also plasmodesmas on the anticlinal walls of endothelial cells. The endothelium and the micropylar integumentary cells play a role in transport of metabolites into the embryo sac.

Corneal endothelium in xeroderma pigmentosum: clinical specular microscopy study.

Science.gov (United States)

Mohamed, Ashik; Peguda, Rajini; Ramappa, Muralidhar; Ali, Mohammad Javed; Chaurasia, Sunita

2016-06-01

Xeroderma pigmentosum is a condition caused due to a defective DNA repair mechanism when exposed to ultraviolet radiation. Many of the patients with this disorder develop severely oedematous cornea with varying degrees of anterior corneal haze, which necessitates a full-thickness keratoplasty or selective endothelial keratoplasty. Presence of corneal oedema suggests that these patients have a dysfunctional endothelium. The purpose of this study is to evaluate the corneal endothelium in the patients with xeroderma pigmentosum when clinical specular microscopy was feasible. Thirteen patients with classic skin changes of xeroderma pigmentosum were included in the study conducted during January 2010-December 2012. An age-matched group of 13 volunteers were included as controls who were emmetropes without any history of ocular or systemic illness. Corneal endothelium was assessed using specular microscopy from the central clear area of cornea. The mean age of the patients with xeroderma pigmentosum was 16.6±7.2 years and that of the controls was 17.4±6.9 years (p=0.78). The number of analysed cells and endothelial cell density were significantly higher in controls (pxeroderma pigmentosum (p≤0.007). The specular microscopic findings in patients with xeroderma pigmentosum are suggestive of an accelerated endothelial cell loss. It is pertinent that the treating physicians must be involved in emphasising proper ocular protection from ultraviolet radiation to prevent avoidable blindness from xeroderma pigmentosum. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Flow regulation in coronary vascular tree: a model study.

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Xinzhou Xie

Full Text Available Coronary blood flow can always be matched to the metabolic demand of the myocardium due to the regulation of vasoactive segments. Myocardial compressive forces play an important role in determining coronary blood flow but its impact on flow regulation is still unknown. The purpose of this study was to develop a coronary specified flow regulation model, which can integrate myocardial compressive forces and other identified regulation factors, to further investigate the coronary blood flow regulation behavior.A theoretical coronary flow regulation model including the myogenic, shear-dependent and metabolic responses was developed. Myocardial compressive forces were included in the modified wall tension model. Shear-dependent response was estimated by using the experimental data from coronary circulation. Capillary density and basal oxygen consumption were specified to corresponding to those in coronary circulation. Zero flow pressure was also modeled by using a simplified capillary model.Pressure-flow relations predicted by the proposed model are consistent with previous experimental data. The predicted diameter changes in small arteries are in good agreement with experiment observations in adenosine infusion and inhibition of NO synthesis conditions. Results demonstrate that the myocardial compressive forces acting on the vessel wall would extend the auto-regulatory range by decreasing the myogenic tone at the given perfusion pressure.Myocardial compressive forces had great impact on coronary auto-regulation effect. The proposed model was proved to be consistent with experiment observations and can be employed to investigate the coronary blood flow regulation effect in physiological and pathophysiological conditions.

Differential effect of amylin on endothelial-dependent vasodilation in mesenteric arteries from control and insulin resistant rats.

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Mariam El Assar

Full Text Available Insulin resistance (IR is frequently associated with endothelial dysfunction and has been proposed to play a major role in cardiovascular disease (CVD. On the other hand, amylin has long been related to IR. However the role of amylin in the vascular dysfunction associated to IR is not well addressed. Therefore, the aim of the study was to assess the effect of acute treatment with amylin on endothelium-dependent vasodilation of isolated mesenteric arteries from control (CR and insulin resistant (IRR rats and to evaluate the possible mechanisms involved. Five week-old male Wistar rats received 20% D-fructose dissolved in drinking water for 8 weeks and were compared with age-matched CR. Plasmatic levels of glucose, insulin and amylin were measured. Mesenteric microvessels were dissected and mounted in wire myographs to evaluate endothelium-dependent vasodilation to acetylcholine. IRR displayed a significant increase in plasmatic levels of glucose, insulin and amylin and reduced endothelium-dependent relaxation when compared to CR. Acute treatment of mesenteric arteries with r-amylin (40 pM deteriorated endothelium-dependent responses in CR. Amylin-induced reduction of endothelial responses was unaffected by the H2O2 scavenger, catalase, but was prevented by the extracellular superoxide scavenger, superoxide dismutase (SOD or the NADPH oxidase inhibitor (VAS2870. By opposite, amylin failed to further inhibit the impaired relaxation in mesenteric arteries of IRR. SOD, or VAS2870, but not catalase, ameliorated the impairment of endothelium-dependent relaxation in IRR. At concentrations present in insulin resistance conditions, amylin impairs endothelium-dependent vasodilation in mircrovessels from rats with preserved vascular function and low levels of endogenous amylin. In IRR with established endothelial dysfunction and elevated levels of amylin, additional exposure to this peptide has no effect on endothelial vasodilation. Increased superoxide

Dynamic, nondestructive imaging of a bioengineered vascular graft endothelium.

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Bryce M Whited

Full Text Available Bioengineering of vascular grafts holds great potential to address the shortcomings associated with autologous and conventional synthetic vascular grafts used for small diameter grafting procedures. Lumen endothelialization of bioengineered vascular grafts is essential to provide an antithrombogenic graft surface to ensure long-term patency after implantation. Conventional methods used to assess endothelialization in vitro typically involve periodic harvesting of the graft for histological sectioning and staining of the lumen. Endpoint testing methods such as these are effective but do not provide real-time information of endothelial cells in their intact microenvironment, rather only a single time point measurement of endothelium development. Therefore, nondestructive methods are needed to provide dynamic information of graft endothelialization and endothelium maturation in vitro. To address this need, we have developed a nondestructive fiber optic based (FOB imaging method that is capable of dynamic assessment of graft endothelialization without disturbing the graft housed in a bioreactor. In this study we demonstrate the capability of the FOB imaging method to quantify electrospun vascular graft endothelialization, EC detachment, and apoptosis in a nondestructive manner. The electrospun scaffold fiber diameter of the graft lumen was systematically varied and the FOB imaging system was used to noninvasively quantify the affect of topography on graft endothelialization over a 7-day period. Additionally, results demonstrated that the FOB imaging method had a greater imaging penetration depth than that of two-photon microscopy. This imaging method is a powerful tool to optimize vascular grafts and bioreactor conditions in vitro, and can be further adapted to monitor endothelium maturation and response to fluid flow bioreactor preconditioning.

Influence of metabolism modifiers of cyclic nucleotides on contractility of right ventricle of rat heart with intact and removed endocardial endothelium

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Savić Slađana

2010-01-01

Full Text Available Introduction. Endocardial endothelium, a natural biological barrier between circulating blood in heart ventricle and cells, creates a complex yet finely tuned balance of interactions with the immediate environment. Objective. We investigated the roles of theophylline, nonspecific phosphodiesterase inhibitor, and imidazole, an activator of phosphodiesterase on contractility of the right ventricle of rat heart, with intact and removed endocardial endothelium. Methods. Adult rats, of both sexes, type Wistar albino, were used in this experiment. All experiments were conducted on the preparations of the right ventricle using two experimental models. In the first experimental model, an endocardial endothelium (EE was preserved, and in the second model, an endocardial endothelium (-EE was removed using 1% solution Triton X-100. Results. Theophylline (1x10-2 mol/l expressed the positive inotropic effect on the heart, regardless of the presence of the endocardial endothelium. Inotropic response as multiple process can be induced by inhibition of phosphodiesterase, accumulation of cyclic nucleotides and activation of Ca2+ channels. Imidazole (2x10-3 mol/l increased the contractility of the right ventricle of the heart with EE. The modulator effect of endocardial endothelium on contractility of imidazole proved to be significant. As imidazole influenced the contractility of the right ventricle only in the presence of the endocardial endothelium, it is assumed that its effect is mediated via deliverance of endothelial mediators with positive inotropic effect. Conclusion. An intact endocardial endothelium is necessary for completion of contractile performance of the heart.

Antithrombotic strategies in patients undergoing percutaneous coronary intervention for acute coronary syndrome

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Son V Pham

2010-09-01

Full Text Available Son V Pham1, Phuong-Chi T Pham2, Phuong-Mai T Pham3, Jeffrey M Miller4, Phuong-Thu T Pham5, Phuong-Anh T Pham61Bay Pines VA Medical Center, Department of Cardiology, Bay Pines, FL, USA; 2Department of Medicine, Nephrology Division, UCLA-Olive View Medical Center, 3Department of Medicine, Greater Los Angeles VA Medical Center, 4Department of Medicine, Hematology-Oncology Division, UCLA-Olive View Medical Center, 5Department of Medicine, Nephrology Division, Kidney and Pancreas Transplant Program, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA; 6Mercy General Hospital, Heart and Vascular Institute, Department of Cardiology, Sacramento, CA, USAAbstract: In patients undergoing percutaneous coronary intervention (PCI for acute coronary syndrome (ACS, both periprocedural acute myocardial infarction and bleeding complications have been shown to be associated with early and late mortality. Current standard antithrombotic therapy after coronary stent implantation consists of lifelong aspirin and clopidogrel for a variable period depending in part on the stent type. Despite its well-established efficacy in reducing cardiac-related death, myocardial infarction, and stroke, dual antiplatelet therapy with aspirin and clopidogrel is not without shortcomings. While clopidogrel may be of little beneficial effect if administered immediately prior to PCI and may even increase major bleeding risk if coronary artery bypass grafting is anticipated, early discontinuation of the drug may result in insufficient antiplatelet coverage with thrombotic complications. Optimal and rapid inhibition of platelet activity to suppress ischemic and thrombotic events while minimizing bleeding complications is an important therapeutic goal in the management of patients undergoing percutaneous coronary intervention. In this article we present an overview of the literature on clinical trials evaluating the different aspects of antithrombotic therapy in patients

3D flow study in a mildly stenotic coronary artery phantom using a whole volume PIV method.

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Brunette, J; Mongrain, R; Laurier, J; Galaz, R; Tardif, J C

2008-11-01

Blood flow dynamics has an important role in atherosclerosis initiation, progression, plaque rupture and thrombosis eventually causing myocardial infarction. In particular, shear stress is involved in platelet activation, endothelium function and secondary flows have been proposed as possible variables in plaque erosion. In order to investigate these three-dimensional flow characteristics in the context of a mild stenotic coronary artery, a whole volume PIV method has been developed and applied to a scaled-up transparent phantom. Experimental three-dimensional velocity data was processed to estimate the 3D shear stress distributions and secondary flows within the flow volume. The results show that shear stress reaches values out of the normal and atheroprotective range at an early stage of the obstructive pathology and that important secondary flows are also initiated at an early stage of the disease. The results also support the concept of a vena contracta associated with the jet in the context of a coronary artery stenosis with the consequence of higher shear stresses in the post-stenotic region in the blood domain than at the vascular wall.

In vivo serial invasive imaging of the second-generation drug-eluting absorbable metal scaffold (Magmaris - DREAMS 2G) in de novo coronary lesions: Insights from the BIOSOLVE-II First-In-Man Trial.

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Garcia-Garcia, Hector M; Haude, Michael; Kuku, Kayode; Hideo-Kajita, Alexandre; Ince, Hüseyin; Abizaid, Alexandre; Tölg, Ralph; Lemos, Pedro Alves; von Birgelen, Clemens; Christiansen, Evald Høj; Wijns, William; Escaned, Javier; Dijkstra, Jouke; Waksman, Ron

2018-03-15

Bioresorbable scaffolds may confer clinical benefit in long-term studies; early mechanistic studies using intravascular imaging have provided insightful information about the immediate and mid-term local serial effects of BRS on the coronary vessel wall. We assessed baseline, 6- and 12-month imaging data of the drug-eluting absorbable metal scaffold (DREAMS 2G). The international, first-in-man BIOSOLVE-II trial enrolled 123 patients with up to 2 de novo lesions (in vessels of 2.2 to 3.7mm). Angiographic based vasomotion, curvature and angulation were assessed; intravascular ultrasound (IVUS) derived radiofrequency (RF) data analysis and echogenicity were evaluated; optical coherence tomography (OCT) attenuation and backscattering analysis were also performed. There was hardly any difference in curvature between pre-procedure and 12months (-0.0019; p=0.48). The change in angulation from pre- to 12months was negligible (-3.58°; 95% CI [-5.97, -1.20]), but statistically significant. At 6months, the change in QCA based minimum lumen diameter in response to high dose of acetylcholine and IVUS-RF necrotic core percentage showed an inverse relationship (estimate of -0.489; p=0.055) and with fibrous volume a positive relationship (estimate of 0.53, p=0.035). Bioresorption analysis by OCT showed that the maximum attenuation values decreased significantly from post-procedure at 6months (Δ 6months vs. post-proc. is -13.5 [95% CI -14.6, -12.4]) and at 12months (Δ 12months vs. post-proc. is -14.0 [95% CI -15.4, -12.6]). By radiofrequency data, the percentage of dense calcium decreased significantly from post-procedure at 6months and at 12months. Likewise, by echogenicity, hyperechogenic structures decreased significantly from post-procedure at 6months; thereafter, they remained unchanged. Following implantation of DREAMS 2G, restoration of the vessel geometry, vasomotion and bioresorption signs were observed at up to 12months; importantly, these changes occurred with

Dynamic interaction between myocardial contraction and coronary flow.

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Beyar, R; Sideman, S

1997-01-01

Phasic coronary flow is determined by the dynamic interaction between central hemodynamics and myocardial and ventricular mechanics. Various models, including the waterfall, intramyocardial pump and myocardial structural models, have been proposed for the coronary circulation. Concepts such as intramyocardial pressure, local elastance and others have been proposed to help explain the coronary compression by the myocardium. Yet some questions remain unresolved, and a new model has recently been proposed, linking a muscle collagen fibrous model to a physiologically based coronary model, and accounting for transport of fluids across the capillaries and lymphatic flow between the interstitial space and the venous system. One of the unique features of this model is that the intramyocardial pressure (IMP) in the interstitial space is calculated from the balance of forces and fluid transport in the system, and is therefore dependent on the coronary pressure conditions, the myocardial function and the transport properties of the system. The model predicts a wide range of experimentally observed phenomena associated with coronary compression.

Role of Coronary Myogenic Response in Pressure-Flow Autoregulation in Swine: A Meta-Analysis With Coronary Flow Modeling

OpenAIRE

Gregory M. Dick; Ravi Namani; Bhavesh Patel; Ghassan S. Kassab

2018-01-01

Myogenic responses (pressure-dependent contractions) of coronary arterioles play a role in autoregulation (relatively constant flow vs. pressure). Publications on myogenic reactivity in swine coronaries vary in caliber, analysis, and degree of responsiveness. Further, data on myogenic responses and autoregulation in swine have not been completely compiled, compared, and modeled. Thus, it has been difficult to understand these physiological phenomena. Our purpose was to: (a) analyze myogenic d...

Calcified Plaque of Coronary Artery: Factors Influencing Overestimation of Coronary Artery Stenosis on Coronary CT Angiography

International Nuclear Information System (INIS)

Kim, Mok Hee; Kim, Yun Hyeon; Choi, Song; Seon, Hyun Ju; Jeong, Gwang Woo; Park, Jin Gyoon; Kang, Heoung Keun; Ko, Joon Seok

2010-01-01

To assess the influence of calcified plaque characteristics on the overestimation of coronary arterial stenosis on a coronary CT angiography (CCTA). The study included 271 coronary arteries with calcified plaques identified by CCTA, and based on 928 coronary arteries from 232 patients who underwent both CCTA and invasive coronary angiography (ICA). Individual coronary arteries were classified into two groups by agreement based on the degree of stenosis from each CCTA and ICA: 1) group A includes patients with concordant CCTA and ICA results and, 2) group B includes patients with an overestimation of CCTA compared to ICA. Parameters including total calcium score, calcium score of an individual coronary artery, calcium burden number of an individual coronary artery, and the density of each calcified plaque (calcium score / number of calcium burden) for each individual coronary artery were compared between the two groups. Of the 271 coronary arteries, 164 (60.5%) were overestimated on CCTA. The left anterior descending artery (LAD) had a significantly low rate of overestimation (47.1%) compared to the other coronary arteries (p=0.001). No significant differences for total calcium score, calcium score of individual coronary artery, and the density of each calcified plaque from individual coronary arteries between two groups was observed. However, a decreasing tendency for the rate of overestimation on CCTA was observed with an increase in calcium burden of individual coronary arteries (p<0.05). The evaluation of coronary arteries suggests that the degree of coronary arterial stenosis had a tendency to be overestimated by calcified plaques on CCTA. However, the rate of overestimation for the degree of coronary arterial stenosis by calcified plaques was not significantly influenced by total calcium score, calcium score of individual coronary artery, and density of each calcified plaque

Coronary blood flow and coronary stenosis correlations in ischemic heart patients; Interventsionalni protseduri pod obrazen kontrol v usloviyata na dobolnichnata pomosht

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Manukov, I [Plovdiv, (Bulgaria)

2003-07-01

The aim of the study is the assessment of the methodology for the C-TIMI frame count by Gibson for easy and fast determination of the coronary blood flow during a selective coronary angiography. 75 patient have been studied with one-branch affection of the coronary arteries. The criteria for exclusion are: myocardial hypertrophy, valve lesions, myocardial infarction and dyslipidemia. Depending of the characteristics of the coronary stenotic changes, the patients have been divided into two groups: 1) Patients with 'ordinary' stenosis of the coronary artery and 2) Patients with 'complex' stenosis. The severity of the stenotic changes in percents is the same for the two groups - 78%{+-}13% vs 81{+-}12%, respectively. In the first group a pronounced correlation is observed between the severity of the coronary stenosis and the slowing of the coronary blood flow. The 'threshold' stenotic level is 89%. In the second group the lowest value of the coronary stenosis is 73% (p>0.01 vs group 1). No correlation is observed between the severity of the coronary stenosis and the slowing of the coronary blood flow. A conclusion is made that the Gibson method for the assessment of the blood flow is convenient for the daily practice not only for the assessment of the significance of the coronary changes, but also for fast analysis of the achieved reconstruction of the coronary arteries after angioplasty. Additional studies of the significance of the different signs of 'complexity' of the coronary stenosis for the slowing of the blood flow are necessary.

Diet-induced obesity impairs endothelium-derived hyperpolarization via altered potassium channel signaling mechanisms.

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Rebecca E Haddock

Full Text Available BACKGROUND: The vascular endothelium plays a critical role in the control of blood flow. Altered endothelium-mediated vasodilator and vasoconstrictor mechanisms underlie key aspects of cardiovascular disease, including those in obesity. Whilst the mechanism of nitric oxide (NO-mediated vasodilation has been extensively studied in obesity, little is known about the impact of obesity on vasodilation to the endothelium-derived hyperpolarization (EDH mechanism; which predominates in smaller resistance vessels and is characterized in this study. METHODOLOGY/PRINCIPAL FINDINGS: Membrane potential, vessel diameter and luminal pressure were recorded in 4(th order mesenteric arteries with pressure-induced myogenic tone, in control and diet-induced obese rats. Obesity, reflecting that of human dietary etiology, was induced with a cafeteria-style diet (∼30 kJ, fat over 16-20 weeks. Age and sexed matched controls received standard chow (∼12 kJ, fat. Channel protein distribution, expression and vessel morphology were determined using immunohistochemistry, Western blotting and ultrastructural techniques. In control and obese rat vessels, acetylcholine-mediated EDH was abolished by small and intermediate conductance calcium-activated potassium channel (SK(Ca/IK(Ca inhibition; with such activity being impaired in obesity. SK(Ca-IK(Ca activation with cyclohexyl-[2-(3,5-dimethyl-pyrazol-1-yl-6-methyl-pyrimidin-4-yl]-amine (CyPPA and 1-ethyl-2-benzimidazolinone (1-EBIO, respectively, hyperpolarized and relaxed vessels from control and obese rats. IK(Ca-mediated EDH contribution was increased in obesity, and associated with altered IK(Ca distribution and elevated expression. In contrast, the SK(Ca-dependent-EDH component was reduced in obesity. Inward-rectifying potassium channel (K(ir and Na(+/K(+-ATPase inhibition by barium/ouabain, respectively, attenuated and abolished EDH in arteries from control and obese rats, respectively; reflecting differential K

HELICOBACTER PYLORI-ASSOCIATED INFLAMMATION IN PATIENTS WITH ACUTE CORONARY SYNDROME

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O. N. Pavlov

2014-07-01

Full Text Available The aim – assessment of the prevalence of seropositivity to Helicobacter pylori infection and laboratory comparative study of the peripheralblood in patients depending on the course of coronary heart disease (CHD.Materials and methods. Observation of 100 patients with coronary artery disease and 40 control patients is presented. Investigation indicatorsof clinical blood tests, biochemical blood analysis and determination of immunoglobulin antibody titer against Helicobacter pylori.Results. In patients with coronary artery disease signs of systemic inflammation associated with the development of acute coronary syndrome are marked with increased antibody titers to infection Helicobacter pylori.Conclusion. A history of coronary artery disease in patients with Helicobacter pylori-associated gastroduodenal pathology should be considered as a factor that increases the likelihood of unstable coronary desease course. Detected in patients with coronary artery disease signs of systemic inflammation with an increase in titer of antibodies to Helicobacter pylori infection associated with development of acute coronary syndrome.

The minimum coronary artery diameter in which coronary spasm can be identified by synchrotron radiation coronary angiography

International Nuclear Information System (INIS)

Matsushita, Shonosuke; Hyodo, Kazuyuki; Imazuru, Tomohiro; Tokunaga, Chiho; Sato, Fujio; Enomoto, Yoshiharu; Hiramatsu, Yuji; Sakakibara, Yuzuru

2008-01-01

Background: Coronary vasospasm is defined as a temporary, intense narrowing of the coronary conduit artery. It brings about ischemic chest pain and becomes one of the causes of myocardial infarction. Coronary spasms are divided into two categories. One is the coronary spasm of the conduit artery and the other is the coronary microvascular spasm. Although coronary spasms are diagnosed with the images of coronary angiography, microvascular spasms cannot be diagnosed because of the limitations of conventional angiographic systems. However, synchrotron radiation coronary angiography (SRCA) can identify coronary arteries down to 100 μm in diameter in the beating heart and 50 μm in arrested heart. Aim: The purpose of this study was to confirm whether microvascular spasms could be identified or not using SRCA, and then down that size identification was possible. Methods: The Langendorff perfusion system with isolated rat hearts was employed. Krebs-Henseleit solution (KH solution) was used as a perfusate. 10 mM of 4-aminopyridine (4-AP: a voltage-gated potassium channel blocker; spasm inducer) was added to the KH solution and maintained for 5 min. SRCA was performed at pre-, during and 10 min after cessation of the KH solution with 4-AP. Coronary spasms were defined as a temporal 75% reduction of coronary arterial diameter. Results and conclusion: Multiple sizes of coronary arteries showed coronary spasms. The minimum stenosed coronary artery size was 100 μm. Since coronary microvascular spasms are seen in the arterioles (50-400 μm), coronary microvascular spasms may be diagnosed with the use of synchrotron radiation coronary angiography

Gap junctions and hydrogen peroxide are involved in endothelium-derived hyperpolarising responses to bradykinin in omental arteries and veins isolated from pregnant women.

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Hammond, Stephanie; Mathewson, Alastair M; Baker, Philip N; Mayhew, Terry M; Dunn, William R

2011-10-01

Altered endothelial function may underlie human cardiovascular diseases, including hypertension, diabetes and pre-eclampsia. While much is known about endothelial function in small arteries, very little is known about endothelial responses in small veins isolated from humans. Therefore, we assessed endothelium-dependent responses in omental arteries and veins isolated from healthy pregnant women, focussing on endothelium-dependent hyperpolarising (EDH) mechanisms. Human omental arteries and veins were obtained from women undergoing elective caesarean sections and examined using pressure myography. In pressurised vessels, the effects of proposed inhibitors of EDH production/function were examined on responses to bradykinin. The expression of connexins Cx37, 40 and 43 was assessed using immunohistochemistry. Bradykinin caused vasodilatation in human pressurised omental arteries and veins. In both vessels, responses to bradykinin were partially blocked in the presence of the gap junction uncoupler, carbenoxolone, and reduced further with the addition of catalase, which acts to degrade H(2)O(2). The effect of catalase alone was more pronounced in venous preparations. All three connexins were expressed in both arteries and veins, with a similar distribution pattern, where Cx37 and Cx40 were located mainly in the endothelium and Cx43 located mostly in the media. These data show that, in human omental vessels, an EDH mechanism is produced in response to bradykinin that involves gap junction communication and the production of H(2)O(2). These mechanisms may be involved in the haemodynamic alterations that take place during pregnancy, and any aberration in their function could contribute to raised blood pressure in hypertensive disorders of pregnancy, such as pre-eclampsia. Copyright © 2011 Elsevier B.V. All rights reserved.

Simulated hypogravity impairs the angiogenic response of endothelium by up-regulating apoptotic signals

International Nuclear Information System (INIS)

Morbidelli, Lucia; Monici, Monica; Marziliano, Nicola; Cogoli, Augusto; Fusi, Franco; Waltenberger, Johannes; Ziche, Marina

2005-01-01

Health hazards in astronauts are represented by cardiovascular problems and impaired bone healing. These disturbances are characterized by a common event, the loss of function by vascular endothelium, leading to impaired angiogenesis. We investigated whether the exposure of cultured endothelial cells to hypogravity condition could affect their behaviour in terms of functional activity, biochemical responses, morphology, and gene expression. Simulated hypogravity conditions for 72 h produced a reduction of cell number. Genomic analysis of endothelial cells exposed to hypogravity revealed that proapoptotic signals increased, while antiapoptotic and proliferation/survival genes were down-regulated by modelled low gravity. Activation of apoptosis was accompanied by morphological changes with mitochondrial disassembly and organelles/cytoplasmic NAD(P)H redistribution, as evidenced by autofluorescence analysis. In this condition cells were not able to respond to angiogenic stimuli in terms of migration and proliferation. Our study documents functional, morphological, and transcription alterations in vascular endothelium exposed to simulated low gravity conditions, thus providing insights on the occurrence of vascular tissue dysregulation in crewmen during prolonged space flights. Moreover, the alteration of vascular endothelium can intervene as a concause in other systemic effects, like bone remodelling, observed in weightlessness

Cultivation of Human Microvascular Endothelial Cells on Topographical Substrates to Mimic the Human Corneal Endothelium

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Jie Shi Chua

2013-03-01

Full Text Available Human corneal endothelial cells have a limited ability to replicate in vivo and in vitro. Allograft transplantation becomes necessary when an accident or trauma results in excessive cell loss. The reconstruction of the cornea endothelium using autologous cell sources is a promising alternative option for therapeutic or in vitro drug testing applications. The native corneal endothelium rests on the Descemet’s membrane, which has nanotopographies of fibers and pores. The use of synthetic topographies mimics the native environment, and it is hypothesized that this can direct the behavior and growth of human microvascular endothelial cells (HMVECs to resemble the corneal endothelium. In this study, HMVECs are cultivated on substrates with micron and nano-scaled pillar and well topographies. Closely packed HMVEC monolayers with polygonal cells and well-developed tight junctions were formed on the topographical substrates. Sodium/potassium (Na+/K+ adenine triphosphatase (ATPase expression was enhanced on the microwells substrate, which also promotes microvilli formation, while more hexagonal-like cells are found on the micropillars samples. The data obtained suggests that the use of optimized surface patterning, in particular, the microtopographies, can induce HMVECs to adopt a more corneal endothelium-like morphology with similar barrier and pump functions. The mechanism involved in cell contact guidance by the specific topographical features will be of interest for future studies.

Atherectomy for calcified coronary lesions: When and how?

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Karatasakis, Aris; Brilakis, Emmanouil S

2016-03-01

Percutaneous coronary intervention of heavily calcified lesions can be challenging. Although the ROTAXUS trial did not demonstrate long-term clinical benefit with routine rotational atherectomy, atherectomy remains an indispensable tool to achieve acute procedural success. Until new data becomes available determining when and how to optimally use coronary atherectomy depends heavily on personal experience and clinical judgment. © 2016 Wiley Periodicals, Inc.

Perfectionism dimensions and dependency in relation to personality vulnerability and psychosocial adjustment in patients with coronary artery disease.

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Dunkley, David M; Schwartzman, Deborah; Looper, Karl J; Sigal, John J; Pierre, Andrena; Kotowycz, Mark A

2012-06-01

The present study sought to illuminate self-criticism and personal standards dimensions of perfectionism and dependency as specific cognitive-personality vulnerability factors that might contribute to a better understanding of numerous psychosocial problem areas that are relevant to coronary artery disease (CAD). One hundred and twenty-three patients diagnosed with clinically significant CAD completed self-report questionnaires. Zero-order correlations and factor analysis results revealed that self-criticism was primarily related to personality vulnerability (aggression/anger/hostility, Type D negative affectivity) and psychosocial maladjustment (depressive symptoms, worry, avoidant coping, support dissatisfaction), whereas personal standards was primarily related to adaptive coping (problem-focused coping, positive reinterpretation) and dependency was primarily related to worry. Hierarchical regression results demonstrated the incremental utility of self-criticism, personal standards, and dependency in relation to (mal)adjustment over and above aggression/anger/hostility, negative affectivity, and social inhibition. Continued efforts to understand the role of perfectionism dimensions and dependency in CAD appear warranted.

[THE INFLUENCE OF MONO- AND MULTIVASCULAR LESIONS OF CORONARY ARTERIES ON THE COURSE OF CORONARY HEART DISEASE IN PATIENTS WITH DIABETES MELLITUS TYPE 2].

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Sypalo, A; Kravchun, P; Kadykova, O

2017-03-01

The article assesses the influence of mono- and multivascular lesions of coronary arteries on the course of coronary heart disease at patients with diabetes mellitus type 2. For this purpose, a comprehensive survey of 75 patients with coronary heart disease and diabetes mellitus type 2 was arranged. Depending on the number of vascular lesions of the coronary arteries, according to the data of coronary arteries computer tomography, all patients were divided into two subgroups. The first subgroup included 27 patients with coronary heart disease and diabetes mellitus type 2 with monovascular lesions of coronary arteries. To the second subgroup were included 48 patients with coronary heart disease and diabetes mellitus type 2 with multivascular lesions of coronary arteries. During the analysis of carbohydrate metabolism in cases of coronary heart disease and diabetes mellitus type 2 the HOMA index increase by 25.40% and insulin level increase by 17.05% were revealed at patients with multivascular lesions of coronary arteries in comparison with patients with monovascular lesions of coronary arteries, respectively. The combination of coronary heart disease and diabetes mellitus type 2 with multivascular lesions of coronary arteries was associated with an increase of sortilin level (233,47±47,85 ng/l). A significant increase in triglycerides, lipoprotein cholesterol of very low density influences greatly on the progression of coronary atherosclerosis with lesions of greater number of coronary arteries at patients surveyed. At patients with coronary heart disease and diabetes mellitus type 2 with multivascular lesions of coronary arteries the left ventricle myocardial re-modeling occurred through the increase of left ventricle's size and cavity.

Changes in corneal endothelium cell characteristics after cataract surgery with and without use of viscoelastic substances during intraocular lens implantation

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Schulze SD

2015-11-01

Full Text Available Stephan D Schulze,1 Thomas Bertelmann,1 Irena Manojlovic,2 Stefan Bodanowitz,2 Sebastian Irle,3 Walter Sekundo11Department of Ophthalmology, Philipps University of Marburg, Marburg, 2Private Practice and Ambulatory Surgical Center, Bremen, 3Freelance Statistician, Friedberg, GermanyPurpose: To evaluate whether the use of balanced salt solution (BSS or an ophthalmic viscoelastic device (OVD during hydrophilic acrylic intraocular lens (IOL implantation variously impacts corneal endothelial cell characteristics in eyes undergoing uneventful phacoemulsifications.Methods: Prospective nonrandomized observational clinical trial. Patients were assigned either to the BSS plus® or to the OVD Z-Celcoat™ group depending on the substance used during IOL implantation. Corneal endothelium cell characteristics were obtained before, 1 week, and 6 weeks after surgery. Intraoperative parameters (eg, surgery time, phacoemulsification energy were recorded.Results: Ninety-seven eyes were assigned to the BSS plus and 86 eyes to the Z-Celcoat group. Preoperative corneal endothelium cell density (ECD and endothelium cell size were 2,506±310 cells/mm2/2,433±261 cells/mm2 and 406±47 µm2/416±50 µm2 (P=0.107/P=0.09. After 1 and 6 weeks, ECD decreased and endothelium cell size increased significantly in both groups (each P<0.001 without significant differences between both groups (each P>0.05. Irrigation–aspiration suction time (30.3±16.6 versus 36.3±14.5 seconds and overall surgical time (7.2±1.2 versus 8.0±1.4 minutes were significantly longer in the OVD Z-Celcoat group (each P<0.001. No complications or serious side effects occurred.Conclusion: Implantation of a hydrophilic acrylic IOL under BSS infusion seems to be a useful and faster alternative in experienced hands without generating higher ECD loss rates.Keywords: phacoemulsification, ophthalmic viscoelastic device, endothelial cell density, IOL

Percutaneous coronary intervention versus coronary-artery bypass grafting for severe coronary artery disease

NARCIS (Netherlands)

P.W.J.C. Serruys (Patrick); M-C. Morice (Marie-Claude); A.P. Kappetein (Arie Pieter); A. Colombo (Antonio); D.R. Holmes Jr (David); M.J. Mack (Michael); E. Stahle (Elisabeth); T.E. Feldman (Ted); M.J.B.M. van den Brand (Marcel); E.J. Bass (Eric); N. van Dyck (Nic); K. Leadly (Katrin); K.D. Dawkins (Keith); F.W. Mohr (Friedrich)

2009-01-01

textabstractBACKGROUND Percutaneous coronary intervention (PCI) involving drug-eluting stents is increasingly used to treat complex coronary artery disease, although coronary-artery bypass grafting (CABG) has been the treatment of choice historically. Our trial compared PCI and CABG for treating

EFFECTS OF ENALAPRIL ON ENDOTHELIUM FUNCTION IN PATIENTS WITH ISCHEMIC HEART DISEASE

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L. I. Katelnizkaya

2006-01-01

Full Text Available Aim. To study endothelium vasomotor function (EF in patients with ischemic heart disease (IHD and the influence of angiotensin converting enzyme inhibitor enalapril (Enam, Dr .Reddy’s, India on it. Material and methods. 87 patients were examined totally. 49 patients were suffering from IHD: 18 patients were younger than 60 years old and 31 patients were older . The combination of arterial hypertension (HT and IHD were registered in 38 patients: 18 patients were below and 20 patients were above 60 years old. All patients additionally to basic IHD therapy took enalapril in dose 2,5-30 mg/daily during 12 weeks. Before the beginning and in the end of treatment cuff test, test with nitroglycerine, bicycle exercise test and Holter monitoring were made, the thickness of intima-media complex of carotid artery and the level of endothelin-1 in blood plasma were defined. Results. EF disorders were shown in IHD, maximal disorders were determined in patients with combination of IHD and HT. EF disorders were also more expressive in patients of elder group. Enalapril restored of cuff tests results, nitroglycerine tests results, reduced a number of myocardial ischemia episodes and provided target blood pressure in 60, 5% patients with HT. Conclusion. Enalapril improves endothelium vasomotor function, endothelium reaction on nitroglycerine and clinical course of IHD and HT.

Tocotrienol Rich Palm Oil Extract Is More Effective Than Pure Tocotrienols at Improving Endothelium-Dependent Relaxation in the Presence of Oxidative Stress

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Saher F. Ali

2015-01-01

Full Text Available Oxidative endothelial dysfunction is a critical initiator of vascular disease. Vitamin E is an effective antioxidant but attempts to use it to treat vascular disorders have been disappointing. This study investigated whether tocotrienols, the less abundant components of vitamin E compared to tocopherols, might be more effective at preserving endothelial function. Superoxide generated by hypoxanthine/xanthine oxidase or rat aorta was measured using lucigenin-enhanced chemiluminescence. The effect of α-tocopherol, α-, δ-, and γ-tocotrienols and a tocotrienol rich palm oil extract (tocomin on levels of superoxide was assessed. Endothelial function in rat aorta was assessed in the presence of the auto-oxidant pyrogallol. Whilst all of the compounds displayed antioxidant activity, the tocotrienols were more effective when superoxide was produced by hypoxanthine/xanthine oxidase whereas tocomin and α-tocopherol were more effective in the isolated aorta. Tocomin and α-tocopherol restored endothelial function in the presence of oxidant stress but α-, δ-, and γ-tocotrienols were ineffective. The protective effect of tocomin was replicated when the tocotrienols were present with, but not without, α-tocopherol. Tocotrienol rich tocomin is more effective than α-tocopherol at reducing oxidative stress and restoring endothelium-dependent relaxation in rat aortae and although α-, δ-, and γ-tocotrienols effectively scavenged superoxide, they did not improve endothelial function.

Tocotrienol Rich Palm Oil Extract Is More Effective Than Pure Tocotrienols at Improving Endothelium-Dependent Relaxation in the Presence of Oxidative Stress

Science.gov (United States)

Ali, Saher F.; Woodman, Owen L.

2015-01-01

Oxidative endothelial dysfunction is a critical initiator of vascular disease. Vitamin E is an effective antioxidant but attempts to use it to treat vascular disorders have been disappointing. This study investigated whether tocotrienols, the less abundant components of vitamin E compared to tocopherols, might be more effective at preserving endothelial function. Superoxide generated by hypoxanthine/xanthine oxidase or rat aorta was measured using lucigenin-enhanced chemiluminescence. The effect of α-tocopherol, α-, δ-, and γ-tocotrienols and a tocotrienol rich palm oil extract (tocomin) on levels of superoxide was assessed. Endothelial function in rat aorta was assessed in the presence of the auto-oxidant pyrogallol. Whilst all of the compounds displayed antioxidant activity, the tocotrienols were more effective when superoxide was produced by hypoxanthine/xanthine oxidase whereas tocomin and α-tocopherol were more effective in the isolated aorta. Tocomin and α-tocopherol restored endothelial function in the presence of oxidant stress but α-, δ-, and γ-tocotrienols were ineffective. The protective effect of tocomin was replicated when the tocotrienols were present with, but not without, α-tocopherol. Tocotrienol rich tocomin is more effective than α-tocopherol at reducing oxidative stress and restoring endothelium-dependent relaxation in rat aortae and although α-, δ-, and γ-tocotrienols effectively scavenged superoxide, they did not improve endothelial function. PMID:26075031

Continuous Perfusion of Saphenous Vein by Oxygenated Blood during Beating Coronary Surgery

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Mohammad Hossein Mandegar

2015-09-01

Full Text Available Background: The saphenous vein remains the most commonly used conduit for coronary artery bypass surgery (CABG. However, the long-term success of surgical revascularization is largely limited by development of occlusion in vein grafts. Objectives: We sought to reduce graft ischemia by maintaining the blood flow into the harvested vein throughout surgery at lowest costs and without special devices. Patients and Methods: This study was conducted on three hundred patients aged 58.5 ± 8 years undergoing elective first-time off-pump CABG with saphenous veins. Results: In addition to preserving nutritional materials and oxygen, the veins harvested via this novel technique did not go into spasm and were not subjected to high-pressure distension, eventually resulting in minimal damage to the endothelium. Conclusions: This technique confers favorable myocardial function and protection in the presence of left ventricular dysfunction, especially in elderly patients.

Intracavitary ultrasound impairs left ventricular performance: presumed role of endocardial endothelium

NARCIS (Netherlands)

Gillebert, T. C.; de Hert, S. G.; Andries, L. J.; Jageneau, A. H.; Brutsaert, D. L.

1992-01-01

Irradiation of isolated cardiac muscle by high-power, high-frequency, continuous wave ultrasound selectively damages endocardial endothelium (EE). We evaluated this ultrasound effect in vivo on the performance of the intact ejecting canine left ventricle (LV). A cylindrical ultrasound probe (0.9

CT coronary angiography vs. invasive coronary angiography in CHD

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Anja Hagen

2012-04-01

Full Text Available Scientific background: Various diagnostic tests including conventional invasive coronary angiography and non-invasive computed tomography (CT coronary angiography are used in the diagnosis of coronary heart disease (CHD. Research questions: The present report aims to evaluate the clinical efficacy, diagnostic accuracy, prognostic value cost-effectiveness as well as the ethical, social and legal implications of CT coronary angiography versus invasive coronary angiography in the diagnosis of CHD. Methods: A systematic literature search was conducted in electronic data bases (MEDLINE, EMBASE etc. in October 2010 and was completed with a manual search. The literature search was restricted to articles published from 2006 in German or English. Two independent reviewers were involved in the selection of the relevant publications. The medical evaluation was based on systematic reviews of diagnostic studies with invasive coronary angiography as the reference standard and on diagnostic studies with intracoronary pressure measurement as the reference standard. Study results were combined in a meta-analysis with 95 % confidence intervals (CI. Additionally, data on radiation doses from current non-systematic reviews were taken into account. A health economic evaluation was performed by modelling from the social perspective with clinical assumptions derived from the meta-analysis and economic assumptions derived from contemporary German sources. Data on special indications (bypass or in-stent-restenosis were not included in the evaluation. Only data obtained using CT scanners with at least 64 slices were considered. Results: No studies were found regarding the clinical efficacy or prognostic value of CT coronary angiography versus conventional invasive coronary angiography in the diagnosis of CHD. Overall, 15 systematic reviews with data from 44 diagnostic studies using invasive coronary angiography as the reference standard (identification of obstructive

Gamma irradiation induces acetylcholine-evoked, endothelium-independent relaxation and activatesk-channels of isolated pulmonary artery of rats

International Nuclear Information System (INIS)

Eder, Veronique; Gautier, Mathieu; Boissiere, Julien; Girardin, Catherine; Rebocho, Manuel; Bonnet, Pierre

2004-01-01

Purpose: To test the effects of irradiation (R*) on the pulmonary artery (PA). Methods and materials: Isolated PA rings were submitted to gamma irradiation (cesium, 8 Gy/min -1 ) at doses of 20 Gy-140 Gy. Rings were placed in an organ chamber, contracted with serotonin (10 -4 M 5-hydroxytryptamine [5-HT]), then exposed to acetylcholine (ACh) in incremental concentrations. Smooth muscle cell (SMC) membrane potential was measured with microelectrodes. Results: A high dose of irradiation (60 Gy) increased 5HT contraction by 20%, whereas lower (20 Gy) doses slightly decreased it compared with control. In the absence of the endothelium, 5-HT precontracted rings exposed to 20 Gy irradiation developed a dose-dependent relaxation induced by acetylcholine (EI-ACh) with maximal relaxation of 60 ± 17% (n = 13). This was totally blocked by L-NAME (10 -4 M), partly by 7-nitro indazole; it was abolished by hypoxia and iberiotoxin, decreased by tetra-ethyl-ammonium, and not affected by free radical scavengers. In irradiated rings, hypoxia induced a slight contraction which was never observed in control rings. No differences in SMC membrane potential were observed between irradiated and nonirradiated PA rings. Conclusion: Irradiation mediates endothelium independent relaxation by a mechanism involving the nitric oxide pathway and K-channels

Cardioplegia cristalóide, barotrauma e função endotelial: considerações experimentais Crystalloid cardioplegia, barotrauma and endothelium function: experimental considerations

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Paulo Roberto B Évora

1996-06-01

effect the endothelium function of epicardic canine coronary arteries. These experiments did not show any alterations at level of receptors (dose-response curves to ACH and ADP; signal transduction/G-proteins (dose-response curve to sodium fluoride; intracellular mechanisms of the EDRF/NO release (dose-response curves to phospholipase C and calcium ionophores A23187. The smooth muscular relaxant function (dose-response curves to sodium nitroprusside and isoproterenol and contarctions (doseresponse curves to KCI and PGF2alpha were also preserved. These experimental observations allow the following speculative considerations: a Should barotrauma be a phenomenon present only in damaged coronary circulation? b All infusion were performed in no more than two or three minutes. Is cardioplegia barotrauma a phenomenon time-dependente? c High levels of potassium could be associated with barotrauma, d Cardioplegia barotrauma is a fancy, at least in our experimental conditions? e Experiments in "organ chambers" study only epicardic arteries. Could barotrauma damage the microcirculation? f The canine coronary circulation is less affeccted by high pressure than human coronaries? These data are suggestive that crystalloid moderately hyperkalemic infusions at high pressures for two or three minutes, do not impair the endothelium release of EDRF/NO of canine epicardic coronary arteries.

Role of Coronary Myogenic Response in Pressure-Flow Autoregulation in Swine: A Meta-Analysis With Coronary Flow Modeling

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Dick, Gregory M.; Namani, Ravi; Patel, Bhavesh; Kassab, Ghassan S.

2018-01-01

Myogenic responses (pressure-dependent contractions) of coronary arterioles play a role in autoregulation (relatively constant flow vs. pressure). Publications on myogenic reactivity in swine coronaries vary in caliber, analysis, and degree of responsiveness. Further, data on myogenic responses and autoregulation in swine have not been completely compiled, compared, and modeled. Thus, it has been difficult to understand these physiological phenomena. Our purpose was to: (a) analyze myogenic data with standard criteria; (b) assign results to diameter categories defined by morphometry; and (c) use our novel multiscale flow model to determine the extent to which ex vivo myogenic reactivity can explain autoregulation in vivo. When myogenic responses from the literature are an input for our model, the predicted coronary autoregulation approaches in vivo observations. More complete and appropriate data are now available to investigate the regulation of coronary blood flow in swine, a highly relevant model for human physiology and disease. PMID:29875686

Role of Coronary Myogenic Response in Pressure-Flow Autoregulation in Swine: A Meta-Analysis With Coronary Flow Modeling

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Gregory M. Dick

2018-05-01

Full Text Available Myogenic responses (pressure-dependent contractions of coronary arterioles play a role in autoregulation (relatively constant flow vs. pressure. Publications on myogenic reactivity in swine coronaries vary in caliber, analysis, and degree of responsiveness. Further, data on myogenic responses and autoregulation in swine have not been completely compiled, compared, and modeled. Thus, it has been difficult to understand these physiological phenomena. Our purpose was to: (a analyze myogenic data with standard criteria; (b assign results to diameter categories defined by morphometry; and (c use our novel multiscale flow model to determine the extent to which ex vivo myogenic reactivity can explain autoregulation in vivo. When myogenic responses from the literature are an input for our model, the predicted coronary autoregulation approaches in vivo observations. More complete and appropriate data are now available to investigate the regulation of coronary blood flow in swine, a highly relevant model for human physiology and disease.

Non-invasive detection of coronary endothelial response to sequential handgrip exercise in coronary artery disease patients and healthy adults.

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Allison G Hays

Full Text Available OBJECTIVES: Our objective is to test the hypothesis that coronary endothelial function (CorEndoFx does not change with repeated isometric handgrip (IHG stress in CAD patients or healthy subjects. BACKGROUND: Coronary responses to endothelial-dependent stressors are important measures of vascular risk that can change in response to environmental stimuli or pharmacologic interventions. The evaluation of the effect of an acute intervention on endothelial response is only valid if the measurement does not change significantly in the short term under normal conditions. Using 3.0 Tesla (T MRI, we non-invasively compared two coronary artery endothelial function measurements separated by a ten minute interval in healthy subjects and patients with coronary artery disease (CAD. METHODS: Twenty healthy adult subjects and 12 CAD patients were studied on a commercial 3.0 T whole-body MR imaging system. Coronary cross-sectional area (CSA, peak diastolic coronary flow velocity (PDFV and blood-flow were quantified before and during continuous IHG stress, an endothelial-dependent stressor. The IHG exercise with imaging was repeated after a 10 minute recovery period. RESULTS: In healthy adults, coronary artery CSA changes and blood-flow increases did not differ between the first and second stresses (mean % change ±SEM, first vs. second stress CSA: 14.8%±3.3% vs. 17.8%±3.6%, p = 0.24; PDFV: 27.5%±4.9% vs. 24.2%±4.5%, p = 0.54; blood-flow: 44.3%±8.3 vs. 44.8%±8.1, p = 0.84. The coronary vasoreactive responses in the CAD patients also did not differ between the first and second stresses (mean % change ±SEM, first stress vs. second stress: CSA: -6.4%±2.0% vs. -5.0%±2.4%, p = 0.22; PDFV: -4.0%±4.6% vs. -4.2%±5.3%, p = 0.83; blood-flow: -9.7%±5.1% vs. -8.7%±6.3%, p = 0.38. CONCLUSION: MRI measures of CorEndoFx are unchanged during repeated isometric handgrip exercise tests in CAD patients and healthy adults. These findings

The atypical structure and function of newborn arterial endothelium is mediated by Rho/Rho kinase signaling.

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Flavahan, Sheila; Flavahan, Nicholas A

2014-08-15

Endothelium of fetal or newborn arteries is atypical, displaying actin stress fibers and reduced nitric oxide (NO)-mediated dilatation. This study tested the hypothesis that Rho/Rho kinase signaling, which promotes endothelial stress fibers and inhibits endothelial dilatation, contributed to this phenotype. Carotid arteries were isolated from newborn [postnatal day 1 (P1)], P7, and P21 mice. Endothelial dilatation to acetylcholine (pressure myograph) was minimal at P1, increased at P7, and further increased at P21. Inhibition of Rho (C3 transferase) or Rho kinase (Y27632, fasudil) significantly increased dilatation to acetylcholine in P1 arteries but had no effect in P7 or P21 arteries. After inhibition of NO synthase (N(G)-nitro-l-arginine methyl ester), Rho kinase inhibition no longer increased acetylcholine responses in P1 arteries. Rho kinase inhibition did not affect dilatation to the NO donor DEA-NONOate. The endothelial actin cytoskeleton was labeled with phalloidin and visualized by laser-scanning microscopy. In P1 arteries, the endothelium had prominent transcytoplasmic stress fibers, whereas in P7 and P21 arteries, the actin fibers had a significantly reduced intensity and were restricted to cell borders. Phosphorylation of myosin light chains, a Rho kinase substrate, was highest in P1 endothelium and significantly reduced in P7 and P21 endothelium (laser-scanning microscopy). In P1 arteries, inhibition of Rho (C3 transferase) or Rho kinase (Y27632) significantly reduced the intensity of actin fibers, which were restricted to cell borders. Similarly, in P1 arteries, Rho inhibition significantly reduced endothelial levels of phosphorylated myosin light chains. These results indicate that the atypical function and morphology of newborn endothelium is mediated by Rho/Rho kinase signaling. Copyright © 2014 the American Physiological Society.

Age-dependent interaction of apolipoprotein E gene with eastern birthplace in Finland affects severity of coronary atherosclerosis and risk of fatal myocardial infarction--Helsinki Sudden Death Study.

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Tyynelä, Petri; Goebeler, Sirkka; Ilveskoski, Erkki; Mikkelsson, Jussi; Perola, Markus; Lehtimäki, Terho; Karhunen, Pekka J

2013-05-01

Mortality from coronary heart disease (CHD) has been constantly higher in eastern late settlement regions compared to western early settlements in Finland, unrelated to classical risk factors. In line with this, eastern birthplace was an age-dependent predictor of severe coronary atherosclerosis and pre-hospital sudden coronary death among male residents of Helsinki. We investigated a possible interaction of apolipoprotein E (APOE) gene with birthplace on the risk of myocardial infarction (MI) and coronary atherosclerosis. APOE genotypes were analyzed in the Helsinki Sudden Death Study series comprising out-of-hospital deaths among males aged 33-70 years (n = 577), who were born in high (east, n = 273) or low (west, n = 304) CHD mortality area. Eastern-born men ≤ 55 years carried 30% more often (P = 0.017) and older men 40% less often (P = 0.022) the APOE ϵ4 allele compared to western-born men (P = 0.003 for birthplace-by-age interaction). In multivariate analysis, the ϵ4 allele associated with the risk of out-of-hospital MI (odds ratio 2.58; 95% CI 1.20-5.55; P = 0.016) only in eastern-born men and with advanced atherosclerosis in both regions of origin, respectively. Birthplace-bound risk of CHD was age-dependently modified by APOE ϵ4 allele, suggesting genetic differences in CHD susceptibility between early and late settlement regions in Finland and providing one explanation for the eastern high mortality.

Integral diagnosis of coronary atherosclerosis by coronary multidetector computed tomography and by invasive coronary angiography

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Llerena Rojas, Luis Roberto; Llerena Rojas, Lorenzo D; Mendoza Rodriguez, Vladimir

2013-01-01

Coronary angiography by multidetector computed tomography (CMDCT) visualizes the wall and lumen of coronary arteries. Invasive coronary angiography (INVCA) only visualizes the arterial lumen but with better resolution

Vitamin D and the endothelium: basic, translational and clinical research updates

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Rinkoo Dalan

2014-09-01

Results and conclusion: Vitamin D deficiency is associated with endothelial dysfunction and cardiovascular diseases. Vitamin D stabilizes the quiescent endothelium, modulates certain stages of endothelial activation, and is involved in the repair of the damaged endothelium in vitro and in vivo. Twelve recent cross sectional studies, including 2086 subjects of varying ethnic groups, show an association between endothelial dysfunction and vitamin D deficiency. Yet 10 recent RCTs of vitamin D supplementation involving 824 subjects have failed to show significant improvements in endothelial function in the short term. So far, RCTs have not been able to confirm or refute the benefit of vitamin D supplementation on vascular mortality. Longer term randomized controlled trials using doses of vitamin D to optimize serum 25(OHD concentrations to 20.0–40.0 ng/mL (50.0–100.0 nmol/L or using vitamin D analogues with no calciotropic effects are needed to assess endothelial function and cardiovascular outcomes.

ENDOTHELIUM LESION MARKERS AND THROMBOCYTE AGGREGATION IN CHRONIC HEPATITIS AND HEPATIC CIRRHOSIS

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A. P. Shchekotova

2012-01-01

Full Text Available Aim — to estimate endothelium lesion, quantity and thrombocyte aggregation function correlation in viral chronic hepatitis C (CHC and hepatic cirrhosis (HC.Materials and methods. 50 CHC patients and 28 HC patients were examined. Using IFA method the total nitric oxide, endothelin‑1, vasculoendothelial growth factor levels, Willebrand factor (vWF activity were investigated, blood plasma desquamated endotheliocyte (DEC number was calculated with Hladovec method, 1978, thrombocyte aggregation (TA with ADP, collagen, ristocetine was determined.Results. DEC and vWF demonstrated correlation in CHC (p = 0.014 and HC (p = 0.000004. In HC patients reliable correlation of all the investigated indices of endothelium lesion with the thrombocyte number and TA was detected, but in CHC patients no correlations were revealed. Thus, significant elevation of TA with ristocetine was noted only in CHC. Decrease in thrombocyte amount among CHC patients and,especially in HC, and heightened vWF activity could change true TA indices. The corrected TA, whose indices in hepatic diseases significantlyincreased, was calculated taking into account the correction factor vWF / thrombocytes that in CHC did not differ from that of healthy patients and in HC was essentially higher.Conclusion. Endothelium dysfunction markers in CH and HC demonstrate correlation with thrombocyte reduction and TA elevation. Determinationof corrected TA permits to reveal disturbances of thrombocyte hemostasis in the form of elevated aggregation in all CHC and HC patients.

Correlation study on waist circumference-triglyceride (WT) index and coronary artery scores in patients with coronary heart disease.

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Yang, R-F; Liu, X-Y; Lin, Z; Zhang, G

2015-01-01

Coronary disease is analyzed through common lipid profiles, but these analyses fail to account for residual risk due to abdominal weight and elevated TG levels. We aimed to investigate the relationship between the waist circumference × triglyceride index (WT index) and the Coronary Artery Score (CAS) in patients with coronary heart disease. 346 patients in our Cardiology Department were recruited from September 2007 to August 2011 and divided into two groups according to whether the patients presented with metabolic syndrome. We performed coronary angiography using the standard Judkins method. The severity of coronary artery stenosis and the CAS were calculated and analyzed with a computerized quantitative analysis system. The signs index, which includes the body mass index (BMI), waist circumference, hip circumference, waist-hip-ratio, and waist-height-ratio, the blood glucose and blood lipid index of all the patients were collected and used to calculate the WT index (waist circumference x triglyceride index. We performed a correlative analysis with age, gender, body mass index, blood glucose and blood lipid, blood pressure and other risk indicators of all patients as the dependent variables and the CAS as the independent variable. We show that the CAS is positively correlated to the WT index. Several lipid profiles and waist circumference were significantly associated with the CAS. The WT index is correlated to the CAS and is a good predictor for the development of coronary artery disease; it can be applied in the clinic for early intervention in populations at risk for coronary heart disease.

Candida glabrata binds to glycosylated and lectinic receptors on the coronary endothelial luminal membrane and inhibits flow sense and cardiac responses to agonists.

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Torres-Tirado, David; Knabb, Maureen; Castaño, Irene; Patrón-Soberano, Araceli; De Las Peñas, Alejandro; Rubio, Rafael

2016-01-01

Candida glabrata (CG) is an opportunistic fungal pathogen that initiates infection by binding to host cells via specific lectin-like adhesin proteins. We have previously shown the importance of lectin-oligosaccharide binding in cardiac responses to flow and agonists. Because of the lectinic-oligosaccharide nature of CG binding, we tested the ability of CG to alter the agonist- and flow-induced changes in cardiac function in isolated perfused guinea pig hearts. Both transmission and scanning electron microscopy showed strong attachment of CG to the coronary endothelium, even after extensive washing. CG shifted the coronary flow vs. auricular-ventricular (AV) delay relationship upward, indicating that greater flow was required to achieve the same AV delay. This effect was completely reversed with mannose, partially reversed with galactose and N-acetylgalactosamine, but hyaluronan had no effect. Western blot analysis was used to determine binding of CG to isolated coronary endothelial luminal membrane (CELM) receptors, and the results indicate that flow-sensitive CELM receptors, ANG II type I, α-adrenergic 1A receptor, endothelin-2, and VCAM-1 bind to CG. In addition, CG inhibited agonist-induced effects of bradykinin, angiotensin, and phenylephrine on AV delay, coronary perfusion pressure, and left ventricular pressure. Mannose reversed the inhibitory effects of CG on the agonist responses. These results suggest that CG directly binds to flow-sensitive CELM receptors via lectinic-oligosaccharide interactions with mannose and disrupts the lectin-oligosaccharide binding necessary for flow-induced cardiac responses. Copyright © 2016 the American Physiological Society.

Distal coronary hemoperfusion during percutaneous transluminal coronary angioplasty

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Muinck, Ebo Derk de

1994-01-01

In this thesis several aspects of passive and active coronary perfusion during coronary angioplasty are investigated. The autoperfusion balloon catheters that were evaluated are the Stack® and the RX-60® catheters (Advanced Cardiovascular Systems, inc., Santa Clara, California, U.S.A). The coronary

Metabolic syndrome enhances endoplasmic reticulum, oxidative stress and leukocyte-endothelium interactions in PCOS.

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Bañuls, Celia; Rovira-Llopis, Susana; Martinez de Marañon, Aranzazu; Veses, Silvia; Jover, Ana; Gomez, Marcelino; Rocha, Milagros; Hernandez-Mijares, Antonio; Victor, Victor M

2017-06-01

Polycystic ovary syndrome (PCOS) is associated with insulin resistance, which can lead to metabolic syndrome (MetS). Oxidative stress and leukocyte-endothelium interactions are related to PCOS. Our aim was to evaluate whether the presence of MetS in PCOS patients can influence endoplasmic reticulum (ER) and oxidative stress and leukocyte-endothelium interactions. This was a prospective controlled study conducted in an academic medical center. The study population consisted of 148 PCOS women (116 without/32 with MetS) and 112 control subjects (87 without / 25 with MetS). Metabolic parameters, reactive oxygen species (ROS) production, ER stress markers (GRP78, sXBP1, ATF6), leukocyte-endothelium interactions, adhesion molecules (VCAM-1, ICAM-1, E-Selectin), TNF-α and IL-6 were determined. Total ROS, inflammatory parameters and adhesion molecules were enhanced in the presence of MetS (pPCOS+MetS group showed higher levels of IL-6 and ICAM-1 than controls (pPCOS and PCOS+MetS groups vs their respective controls (pPCOS groups (pPCOS+MetS patients exhibited higher GRP78 and ATF6 levels than controls and PCOS patients without MetS (pPCOS women, HOMA-IR was positively correlated with ICAM-1 (r=0.501; pPCOS, all of which are related to vascular complications. Copyright © 2017 Elsevier Inc. All rights reserved.

Balloon angioplasty in acute and chronic coronary artery disease

International Nuclear Information System (INIS)

Holmes, D.R. Jr.; Vlietstra, R.E.

1989-01-01

Percutaneous transluminal coronary angioplasty has grown exponentially since its introduction. Currently, selection criteria include single-vessel and multivessel disease, stable and unstable angina, and acute infarction. The outcome depends on specific patient and antiographic characteristics. In ideal lesions, success rates should be greater than 90%, with low morbidity and mortality. With more severe and diffuse multivessel disease, success rates are lower and complication rates are higher. In these cases, percutaneous transluminal coronary angioplasty still offers a reasonable option, provided complete revascularization can be achieved or the angina-producing lesion dilated. Numerous issues remain unresolved, including (1) the role of percutaneous transluminal coronary angioplasty vs coronary surgery (currently being tested), (2) restenosis, which occurs in approximately 30% of treated lesions, and (3) organizational adjustments such as training and certification to maintain high standards of care

HUMAN CORONARY ARTERIES- A STUDY BASED ON GROSS ANATOMY AND CORONARY CAST

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Vijayamma K. N

2018-01-01

Full Text Available BACKGROUND Present study is an attempt to throw light upon the coronary arterial pattern, variations in arterial distribution and extent of intercoronary anastomosis and arterial preponderance in different age groups. MATERIALS AND METHODS Total of 115 hearts were made use for this study. Ninety hearts were dissected for the gross anatomical study of coronary arteries and 25 hearts including three fetal hearts were used for the coronary cast study. The right and left coronary arteries were traced from aortic sinus along the atrioventricular groove to the area of its termination. The atrial ventricular and septal branches were traced and looked for anastomosis. Coronary casts were prepared by injecting coloured liquid latex through the coronary ostia and the branching pattern and anastomosis were studied. The coronary arterial pattern, extent of distribution of its branches, arterial preponderance and variations were observed. RESULTS It was found that 73 % cases of SA nodal branch arise from right coronary artery and 27 % from circumflex branch of left coronary artery. SA node has dual blood supply from both coronary arteries in 4% cases. Right coronary preponderance was observed in 83% of cases and left coronary preponderance in 11 % cases, and balanced supply in 6% cases. Coronary cast was helpful to understand the branching pattern of vessels, and the anastomosis of small capillaries. It was also seen that all 11 % of left preponderance were seen in male hearts and all of the 31 female hearts dissected were right preponderant. CONCLUSION Coronary arteries are called end arteries functionally. Right coronary artery originates from anterior aortic sinus in all cases except one which takes origin from posterior left aortic sinus along with left coronary artery. Right coronary preponderance is observed in 83% cases. Left coronary artery branching pattern shows variability. Left coronary preponderance was observed in 11% and all cases are male

A comparison of hybrid coronary revascularization and off-pump coronary revascularization.

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Umakanthan, Ramanan; Leacche, Marzia; Gallion, Anna H; Byrne, John G

2013-04-01

Minimally invasive approaches to treat vascular disease have been accruing significant popularity over the last several decades. Due to progressive advances in technology, a variety of techniques are being now utilized in the field of cardiovascular surgery. The objectives of minimally invasive techniques are to curtail operative trauma and minimize perioperative morbidity without decreasing the quality of the treatment. The standard surgical approach for the treatment of coronary artery disease has traditionally been coronary artery bypass grafting surgery via median sternotomy. Off-pump coronary artery bypass grafting surgery offers a less invasive alternative and enables coronary revascularization to be performed without cardiopulmonary bypass. Hybrid coronary revascularization offers an even less invasive option in which minimally invasive direct coronary artery bypass can be combined with percutaneous coronary intervention. In this article, the authors review a recent publication comparing hybrid coronary revascularization and off-pump coronary artery bypass grafting surgery.

Permeability of the arterial endothelium of spontaneously hypertensive rats to plasma macromolecules

International Nuclear Information System (INIS)

Yurukova, Z.B.; Georgiev, P.G.

1979-01-01

By means of vascular labelling technique at cellular level, the permeability of the arterial endothelium of spontaneously hypertensive rats has been studied. For this purpose colloidal carbon and plasma lipoproteins were introduced into the jugular vein of the animals. Material for light- and electron-microscopic and radioautographic examinations was taken from the thoracic and abdominal parts of the aorta. The results show that in long-term hypertension substances from plasma enter the aortic wall in increased amounts through two main pathways. First, through the selective physiological pathways of transendothelial transport (through cell junctions and vesicular transport) and secondly, through discontinuities of the endothelial lining (separation of the intercellular junctions, areas of loss of one to several endothelial cells). The alteration of the arterial endothelium barrier function in chronic hypertension seems to be an important mechanism for the progression of hypertensive arterial lesions. (A.B.)

[Effects of sodium ethamsylate on anticoagulant and anti-aggregation activity of vascular endothelium in hemorrhagic fever patients with renal syndrome].

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Davidovich, I M; Sirotin, B Z; Parshina, T A

1999-01-01

To elucidate effects of sodium ethamsylate (SE) on anticoagulant and antiaggregation activity of vascular endothelium in patients suffering from hemorrhagic fever with renal syndrome (HFRS). A trial of SE enrolled 70 HFRS patients (58 males, 12 females aged under 30 years) compatible by the disease severity. They were divided into two groups. 42 patients of the control group received standard therapy, 28 patients of the study group received adjuvant 12% solution of SE in daily dose 1500-2000 mg in the course of HFRS oliguria period. Hemostatic parameters were measured before and after the cuff test to investigate the condition of vascular wall with calculation of the athrombogenicity index (the ratio of the relevant indices before and after the cuff test). SE effects on vascular endothelium was assessed by a blind method. In oliguria, both groups had baseline antiaggregation indices significantly higher than in the control. After the cuff test, control patients' indices tended to an increase while in the study group there was a marked decrease. The trend in anticoagulant activity of microvascular endothelium did not differ much with the groups. This picture persisted also in polyuria. In convalescence hemostasis was similar in both groups. SE enhances antiaggregant activity of vascular endothelium in oliguria period of HFRS without affecting its anticoagulant properties. This is explained by a direct effect of SE on vascular endothelium.

Targeted modulation of reactive oxygen species in the vascular endothelium.

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Shuvaev, Vladimir V; Muzykantov, Vladimir R

2011-07-15

'Endothelial cells lining vascular luminal surface represent an important site of signaling and injurious effects of reactive oxygen species (ROS) produced by other cells and endothelium itself in ischemia, inflammation and other pathological conditions. Targeted delivery of ROS modulating enzymes conjugated with antibodies to endothelial surface molecules (vascular immunotargeting) provides site-specific interventions in the endothelial ROS, unattainable by other formulations including PEG-modified enzymes. Targeting of ROS generating enzymes (e.g., glucose oxidase) provides ROS- and site-specific models of endothelial oxidative stress, whereas targeting of antioxidant enzymes SOD and catalase offers site-specific quenching of superoxide anion and H(2)O(2). These targeted antioxidant interventions help to clarify specific role of endothelial ROS in vascular and pulmonary pathologies and provide basis for design of targeted therapeutics for treatment of these pathologies. In particular, antibody/catalase conjugates alleviate acute lung ischemia/reperfusion injury, whereas antibody/SOD conjugates inhibit ROS-mediated vasoconstriction and inflammatory endothelial signaling. Encapsulation in protease-resistant, ROS-permeable carriers targeted to endothelium prolongs protective effects of antioxidant enzymes, further diversifying the means for targeted modulation of endothelial ROS. Copyright © 2011 Elsevier B.V. All rights reserved.

Cytokine-free directed differentiation of human pluripotent stem cells efficiently produces hemogenic endothelium with lymphoid potential.

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Galat, Yekaterina; Dambaeva, Svetlana; Elcheva, Irina; Khanolkar, Aaruni; Beaman, Kenneth; Iannaccone, Philip M; Galat, Vasiliy

2017-03-17

The robust generation of human hematopoietic progenitor cells from induced or embryonic pluripotent stem cells would be beneficial for multiple areas of research, including mechanistic studies of hematopoiesis, the development of cellular therapies for autoimmune diseases, induced transplant tolerance, anticancer immunotherapies, disease modeling, and drug/toxicity screening. Over the past years, significant progress has been made in identifying effective protocols for hematopoietic differentiation from pluripotent stem cells and understanding stages of mesodermal, endothelial, and hematopoietic specification. Thus, it has been shown that variations in cytokine and inhibitory molecule treatments in the first few days of hematopoietic differentiation define primitive versus definitive potential of produced hematopoietic progenitor cells. The majority of current feeder-free, defined systems for hematopoietic induction from pluripotent stem cells include prolonged incubations with various cytokines that make the differentiation process complex and time consuming. We established that the application of Wnt agonist CHIR99021 efficiently promotes differentiation of human pluripotent stem cells in the absence of any hematopoietic cytokines to the stage of hemogenic endothelium capable of definitive hematopoiesis. The hemogenic endothelium differentiation was accomplished in an adherent, serum-free culture system by applying CHIR99021. Hemogenic endothelium progenitor cells were isolated on day 5 of differentiation and evaluated for their endothelial, myeloid, and lymphoid potential. Monolayer induction based on GSK3 inhibition, described here, yielded a large number of CD31 + CD34 + hemogenic endothelium cells. When isolated and propagated in adherent conditions, these progenitors gave rise to mature endothelium. When further cocultured with OP9 mouse stromal cells, these progenitors gave rise to various cells of myeloid lineages as well as natural killer lymphoid, T

Targeted modulation of reactive oxygen species in the vascular endothelium

OpenAIRE

Shuvaev, Vladimir V.; Muzykantov, Vladimir R.

2011-01-01

Endothelial cells lining vascular luminal surface represent an important site of signaling and injurious effects of reactive oxygen species (ROS) produced by other cells and endothelium itself in ischemia, inflammation and other pathological conditions. Targeted delivery of ROS modulating enzymes conjugated with antibodies to endothelial surface molecules (vascular immunotargeting) provides site-specific interventions in the endothelial ROS, unattainable by other formulations including PEG-mo...

Adaptação de um sistema de ensaio biológico para detecção de fatores relaxantes endoteliais derivados do endocárdio atrial canino Adaptation of bioassay to detect endothelium-derived relaxing factors from the canine atrial endocardium

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Yeow Leng Chua

2009-06-01

Full Text Available OBJETIVO: Estudar a liberação de fatores relaxantes derivados do endotélio (EDRF pelo endocárdio de aurículas de corações caninos. MÉTODOS: Aurículas atriais caninas foram suturadas em forma de tubos e o efluente desses tubos foram submetidos a ensaios biológicos (sistema de perfusão isolada em câmaras de órgãos utilizando artéria coronária canina, para a detecção de EDRFs. RESULTADOS: O efluente da aurícula direita promoveu relaxamento de 58,4 + 10,1% e da aurícula esquerda 74,9 + 8,5% da contração inicial obtida pela ação da prostagladina F2α em artéria coronária. Não houve diferença estatística no relaxamento da artéria coronária induzido pelos efluentes das aurículas direita e esquerda. O relaxamento induzido pelos efluentes das aurículas direita e esquerda foi abolido pelo tratamento das mesmas com Triton X-100. O tratamento das aurículas com L-NMMA, um inibidor competitivo da síntese de óxido nítrico, e com indometacina, um inibidor da via da ciclooxigenase, promoveu redução no relaxamento da artéria coronária induzido pelo efluente auricular, indicando que o endotélio endocárdico libera óxido nítrico e prostanóides. CONCLUSÕES: Esse estudo demonstra, pela primeira vez, a liberação luminal in vitro de EDRF e prostaciclina pelo átrio de coração canino. A habilidade do endotélio endocárdico em produzir esses fatores pode ter um papel importante na prevenção da formação de trombos nas câmaras cardíacas.OBJECTIVE: The aim of this study was to assess the release of endothelium-derived relaxing factors from the endocardium of canine atrial appendage. METHODS: To study the release of endothelium-derived relaxing factor (EDRF from intact atrial endocardial endothelium, tube-shaped sutures of canine atrial appendages were performed and effluents from these tubes were bioassayed (isolated perfused organ chamber system for detection of EDRF in canine coronary artery. RESULTS: Effluent from

The dynamics of the coronary collateral circulation.

Science.gov (United States)

Zimarino, Marco; D'Andreamatteo, Mariangela; Waksman, Ron; Epstein, Stephen E; De Caterina, Raffaele

2014-04-01

Coronary collaterals are present at birth, with wide interindividual variation in their functional capacity. These vessels protect jeopardized myocardium, and the number of collaterals and the extent of their coverage are associated with improved survival in patients with coronary heart disease. The collateral circulation is not a permanent set of structures, but undergoes dynamic changes with important consequences for cardioprotection. If a severe atherosclerotic lesion develops in an artery supplying tissue downstream of a total occlusion through collateral blood flow, pressure gradients across the collateral bed change. The result is that some of the collateral flow previously supplying the perfusion territory of the totally occluded artery is redirected to the perfusion territory of the donor artery, thus producing a 'collateral steal'. The collateral circulation can regress once antegrade flow in the main dependent artery is re-established, as occurs following the recanalization of a chronic total occlusion. The clinical benefits of coronary revascularization must be cautiously weighed against the risk of reducing the protective support derived from coronary collaterals. Consequently, pharmacological, gene-based, and cell-based therapeutic attempts have been made to enhance collateral function. Although such approaches have so far yielded no, or modest, beneficial results, the rapidly accruing data on coronary collateral circulation will hopefully lead to new effective therapeutic strategies.

First experience with multidetector-CT for the diagnosis of coronary atherosclerosis

International Nuclear Information System (INIS)

Becker, C.R.; Hong, C.; Schoepf, U.J.; Reiser, M.F.; Knez, A.; Leber, A.; Treede, H.; Wildhirt, S.; Ohnesorge, B.; Flohr, T.

2000-01-01

Purpose: Multirow-detector-spiral-CT (MSCT) allows for 250 ms effective exposure time. The purpose of this study was to demonstrate the possibilities and limitations of this CT technology for non enhanced and contrast enhanced investigation of the coronary arteries. Methods: Investigation of the coronary arteries without contrast medium for quantification of coronary calcifications was performed in an obese patient (140 kg) with MSCT and electron beam CT (EBCT). In 56 patients contrast enhanced CT angiography of the coronary arteries was performed to determine image quality depending on the heart rate. Results: In the obese patient superior image quality could be achieved with MSCT allowing for reliable quantification of coronary calcifications. With MSCT angiography of the coronary arteries good image quality was achieved in patients with a heart rate of 59±8 beats per minute. Conclusion: Even if there are limitations in patients with higher heart rates with an effective exposure time of 250 ms MSCT has clear advantage of image quality in the assessment of non enhanced and contrast enhanced coronary arteries. (orig.) [de

[Developments in percutaneous coronary intervention and coronary stents].

Science.gov (United States)

Simsek, C; Daemen, J; Zijlstra, F

2014-01-01

In The Netherlands, more than 30.000 patients undergo a percutaneous coronary intervention every year, during which a coronary stent implantation will be performed in 90% of the cases. It is estimated that more than 5 million coronary stent implantations will be performed worldwide this year. While these numbers are impressive, however, coronary stents still have as a limitation the possibility of stent thrombosis. This has been and is an important stimulus for the development of both coronary stents, from a bare metal stent via a drug eluting stent to the present-day development of bio-absorbable stents, and anti-platelet drugs,from acenocoumarol to thieropyridines. The possibility of shortening the period of use of this powerful medication by developing new kinds of non-thrombogenic stents would, for example, make it possible to achieve significant reductions in subsequent bleeding during (dental) procedures.

Hierarchical nitrogen-doped porous carbon with high surface area derived from endothelium corneum gigeriae galli for high-performance supercapacitor

International Nuclear Information System (INIS)

Hong, Xiaoting; Hui, K.S.; Zeng, Zhi; Hui, K.N.; Zhang, Luojiang; Mo, Mingyue; Li, Min

2014-01-01

Highlights: • Porous carbons were prepared using endothelium corneum gigeriae galli as precursor. • Surface and structural properties strongly depend on carbonization temperatures. • Resultant carbons possess nitrogen heteroatom and high surface areas. • ECGG-900 sample exhibits excellent electrochemical capacitive performances. - Abstract: Endothelium corneum gigeriae galli derived 3D hierarchical nitrogen-doped porous carbon was for the first time prepared by preliminary carbonization at 450 °C and final KOH activation at high temperatures. The surface and structural properties of the as-synthesized samples are analyzed with Brunauer–Emmett–Teller surface analyzer apparatus, X-Ray Diffractometer, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectrometer. The electrochemical performances are analyzed by cyclic voltammetry, galvanostatic charge/discharge cycling and electrochemical impedance spectroscopy. The obtained results show that the sample carbonized at 900 °C possesses the SSA of 2149.9 m 2 g −1 , average micropore diameter of 1.78 nm, and exhibits the highest initial specific capacitance of 198.0 F g −1 at current density of 1 A g −1 in 6 M KOH solution. It retains good specific capacitance retention of 91.6% after 3000 charge/discharge cycles at current density of 2 A g −1

Time-dependent 3D simulations of the hemodynamics in a stented coronary artery

International Nuclear Information System (INIS)

Faik, Isam; Mongrain, Rosaire; Leask, Richard L; Rodes-Cabau, Josep; Larose, Eric; Bertrand, Olivier

2007-01-01

Stenting is becoming the major interventional cardiology procedure worldwide. However restenosis remains a major limitation to the effectiveness of stents. Alterations to the local hemodynamics in the stented segment of the artery could be a potential factor in the development of in-stent restenosis. The characterization of wall shear stress and of blood flow patterns in a stented artery is therefore necessary for a good understanding of the role of hemodynamics in the development of in-stent restenosis. We have used a time-dependent 3D numerical model of a stented coronary artery to study the characteristics of the blood flow and the shear stress distribution. Our results show that the presence of the stent produces significant secondary flow that is limited to an annulus in the near wall region. Low shear stress zones were localized in the vicinity of the struts while the tips of the struts exhibited high values of shear stress. These results support the hypothesis that local hemodynamics may affect the development of in-stent restenosis and could influence the choice of stent geometries for future stent designs

Anomalous origin of right coronary artery from left coronary sinus.

Science.gov (United States)

Hamzeh, Gadah; Crespo, Alex; Estarán, Rafael; Rodríguez, Miguel A; Voces, Roberto; Aramendi, José I

2008-08-01

Anomalous aortic origin of the coronary arteries is uncommon but clinically significant. Manifestations vary from asymptomatic patients to those who present with angina pectoris, myocardial infarction, heart failure, syncope, arrhythmias, and sudden death. We describe 4 patients, aged 34 to 59 years, who were diagnosed with right coronary artery arising from the left sinus of Valsalva, confirmed by coronary angiography, which was surgically repaired. Three patients presented dyspnea and angina, and one with acute myocardial infarction. At operation, the right coronary artery was dissected at the take-off from the intramural course, and reimplanted into the right sinus of Valsalva. There was no mortality. One patient had associated coronary artery disease that required stent placement postoperatively. This reimplantation technique provides a good physiological and anatomical repair, eliminates a slit-like ostium, avoids compression of the coronary artery between the aorta and the pulmonary artery, and gives superior results to coronary artery bypass grafting or the unroofing technique.

Coronary CT Angiography in the Quantitative Assessment of Coronary Plaques

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Zhonghua Sun

2014-01-01

Full Text Available Coronary computed tomography angiography (CCTA has been recently evaluated for its ability to assess coronary plaque characteristics, including plaque composition. Identification of the relationship between plaque composition by CCTA and patient clinical presentations may provide insight into the pathophysiology of coronary artery plaque, thus assisting identification of vulnerable plaques which are associated with the development of acute coronary syndrome. CCTA-generated 3D visualizations allow evaluation of both coronary lesions and lumen changes, which are considered to enhance the diagnostic performance of CCTA. The purpose of this review is to discuss the recent developments that have occurred in the field of CCTA with regard to its diagnostic accuracy in the quantitative assessment of coronary plaques, with a focus on the characterization of plaque components and identification of vulnerable plaques.

Detection of coronary calcification in ultrafast CT compared to coronary angiography

International Nuclear Information System (INIS)

Koesling, S.; Hoffmann, U.; Rother, T.; Lieberenz, S.; Heywang-Koebrunner, S.H.; Schulz, H.G.

1994-01-01

The angiographical findings of 24 patients with coronary artery disease were compared with qualitative and quantitative detection of coronary calcification by ultrafast CT. Doubts concerning the capabilities of the ultrafast CT for a screening of coronary artery disease arise when the results of one third false positive and fase negative findings are considered. Variations in the quantification of coronary calcification were too great to allow a realistic assessment of the degree of stenosis of the coronary arteries. (orig.) [de

Large right ventricular sinusoids in an infant with aorta-left ventricular tunnel and proximal right coronary artery atresia.

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Chen, Peter C; Spinner, Joseph A; Heinle, Jeffrey S

2018-07-01

We report a 1-month-old infant diagnosed with an aorta-left ventricular tunnel, ventricular septal defect, and right coronary atresia with right ventricular sinusoids. The patient's anatomy and physiology did not indicate right-ventricular-dependent coronary circulation, and therefore right ventricular decompression could be performed without compromising coronary perfusion during surgical correction. A detailed understanding of the coronary anatomy is critical in managing this defect when coronary anomalies are present.

Cross-talk between cardiac muscle and coronary vasculature.

Science.gov (United States)

Westerhof, Nico; Boer, Christa; Lamberts, Regis R; Sipkema, Pieter

2006-10-01

The cardiac muscle and the coronary vasculature are in close proximity to each other, and a two-way interaction, called cross-talk, exists. Here we focus on the mechanical aspects of cross-talk including the role of the extracellular matrix. Cardiac muscle affects the coronary vasculature. In diastole, the effect of the cardiac muscle on the coronary vasculature depends on the (changes in) muscle length but appears to be small. In systole, coronary artery inflow is impeded, or even reversed, and venous outflow is augmented. These systolic effects are explained by two mechanisms. The waterfall model and the intramyocardial pump model are based on an intramyocardial pressure, assumed to be proportional to ventricular pressure. They explain the global effects of contraction on coronary flow and the effects of contraction in the layers of the heart wall. The varying elastance model, the muscle shortening and thickening model, and the vascular deformation model are based on direct contact between muscles and vessels. They predict global effects as well as differences on flow in layers and flow heterogeneity due to contraction. The relative contributions of these two mechanisms depend on the wall layer (epi- or endocardial) and type of contraction (isovolumic or shortening). Intramyocardial pressure results from (local) muscle contraction and to what extent the interstitial cavity contracts isovolumically. This explains why small arterioles and venules do not collapse in systole. Coronary vasculature affects the cardiac muscle. In diastole, at physiological ventricular volumes, an increase in coronary perfusion pressure increases ventricular stiffness, but the effect is small. In systole, there are two mechanisms by which coronary perfusion affects cardiac contractility. Increased perfusion pressure increases microvascular volume, thereby opening stretch-activated ion channels, resulting in an increased intracellular Ca2+ transient, which is followed by an increase in Ca

THE ROLE OF ENDOTHELIUM FUNCTIONAL STATUS IN PULMONARY HYPERTENSION DEVELOPMENT AMONG CHILDREN

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S.N. Ivanov

2008-01-01

Full Text Available The background paper approaches the problems of functional status of endothelium, significance of vasоactive substances as markers of endothelial dysfunction and reason of its development, role of endothelial dysfunction in the pathogenesis of primary and secondary pulmonary hypertension.Key words: pulmonary hypertension, endothelial dysfunction, vasoactive substances.

Contrast-Induced Nephropathy Is Less Common in Patients with Good Coronary Collateral Circulation.

Science.gov (United States)

Avci, Eyup; Yildirim, Tarik; Kadi, Hasan

2017-10-01

Contrast-induced nephropathy (CIN) is a typically reversible type of acute renal failure that develops after exposure to contrast agents; underlying endothelial dysfunction is thought to be an important risk factor for CIN. Although the mechanism of coronary collateral circulation (CCC) is not fully understood, a pivotal role of the endothelium has been reported in many studies. The aim of this study was to investigate whether there is a relationship between CCC and CIN. Patients with at least one occluded major coronary artery and blood creatinine analyses performed before and on the second day after angiography were included in the study. CIN was defined as a 25% or greater elevation of creatinine on the second day after exposure to the contrast agent. Collateral grading was performed according to the Rentrop classification. Patients were grouped according to whether they developed CIN or not, i.e., CIN(-) and CIN(+) group. A total of 214 patients who met the inclusion criteria were included in the study. CIN was diagnosed in 43 patients (20.1%) in the study population. Good CCC was identified in 112 patients (65.5%) in the CIN(-) group, whereas it was identified in 13 patients (30.2%) in the CIN(+) group. In the CIN(-) group, good CCC was significantly more frequent ( p Good collateral circulation was associated with a lower frequency of CIN, and poor collateral circulation was an independent predictor of CIN.

LPS from Porphyromonas gingivalis increases the sensitivity of contractile response mediated by endothelin-B (ET(B)) receptors in cultured endothelium-intact rat coronary arteries

DEFF Research Database (Denmark)

Ghorbani, Bahareh; Holmstrup, Palle; Edvinsson, Lars

2010-01-01

The purpose of our study was to examine if lipopolysaccharide (LPS) from Porphyromonas gingivalis (P.g.) modifies the vasomotor responses to Endothelin-1 (ET-1) and Sarafotoxin 6c (S6c) in rat coronary arteries. The arteries were studied directly or following organ culture for 24h in absence...

Early dynamic fate changes in haemogenic endothelium characterized at the single-cell level

Science.gov (United States)

Swiers, Gemma; Baumann, Claudia; O'Rourke, John; Giannoulatou, Eleni; Taylor, Stephen; Joshi, Anagha; Moignard, Victoria; Pina, Cristina; Bee, Thomas; Kokkaliaris, Konstantinos D.; Yoshimoto, Momoko; Yoder, Mervin C.; Frampton, Jon; Schroeder, Timm; Enver, Tariq; Göttgens, Berthold; de Bruijn, Marella F. T. R.

2013-12-01

Haematopoietic stem cells (HSCs) are the founding cells of the adult haematopoietic system, born during ontogeny from a specialized subset of endothelium, the haemogenic endothelium (HE) via an endothelial-to-haematopoietic transition (EHT). Although recently imaged in real time, the underlying mechanism of EHT is still poorly understood. We have generated a Runx1 +23 enhancer-reporter transgenic mouse (23GFP) for the prospective isolation of HE throughout embryonic development. Here we perform functional analysis of over 1,800 and transcriptional analysis of 268 single 23GFP+ HE cells to explore the onset of EHT at the single-cell level. We show that initiation of the haematopoietic programme occurs in cells still embedded in the endothelial layer, and is accompanied by a previously unrecognized early loss of endothelial potential before HSCs emerge. Our data therefore provide important insights on the timeline of early haematopoietic commitment.

Assessment of endothelium: Dependent vasodilation with a non-invasive method in patients with preeclampsia compared to normotensive pregnant women

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Seyedeh Zahra Allameh

2014-01-01

Full Text Available Background: To assess the endothelial function via noninvasive method, in pregnant women with preeclampsia compared to to normotensive pregnant women. Materials and Methods: Brachial artery diameter was measured via ultrasound, in 28 women with preeclampcia in case group and normotensive pregnant women in control group, at rest, after inflation of sphygmomanometer cuff up to 250-300 mmHg, immediately after deflation of the cuff, 60-90 minutes later and 5 min after administration of sublingual trinitroglycerin (TNG. Results of these measurements as well as demographic characteristics of participants in both groups were recorded in special forms. Data were analyzed via Statistical Package for Social Sciences (SPSS version 16, using t-test and repeated measures analysis of variance (ANOVA. P-value < 0.05 was considered statistically significant. The results were presented as mean ± standard deviation (SD. Results: The mean of brachial artery diameter at rest in the case and control groups was 4.49 ± 0.39 and 4.08 ± 0.38 mm, respectively (P = 0.1. Also the results showed that the brachial artery diameter, immediately after deflation of the cuff, was 4.84 ± 0.4 and 4.37 ± 0.30 mm in the case and control groups (P < 0.001, respectively. The mean brachial artery diameter, 60-90 s after deflation of the cuff, was 4.82 ± 0.41 and 4.42 ± 0.38 mm in the case and control groups (P < 0.00, respectively. The brachial artery diameter, 5 min after sublingual NO administration, was 4.95 ± 0.6 and 4.40 ± 0.45 mm in case and control groups (P < 0.001, respectively. Applying of repeated measures ANOVA showed that the mean difference between case and control groups was statistically significant (P < 0.001. Conclusion: Current study concluded that there is no difference in endothelium-dependent vasodilation between women with preeclampsia and pregnant women with normal blood pressure.

Assessment of coronary artery disease by post-mortem cardiac MR

International Nuclear Information System (INIS)

Ruder, Thomas D.; Bauer-Kreutz, Regula; Ampanozi, Garyfalia; Rosskopf, Andrea B.; Pilgrim, Thomas M.; Weber, Oliver M.; Thali, Michael J.; Hatch, Gary M.

2012-01-01

Objectives: Minimally invasive or virtual autopsies are being advocated as alternative to traditional autopsy, but have limited abilities to detect coronary artery disease. It was the objective of this study to assess if the occurrence of chemical shift artifacts (CSA) along the coronary arteries on non-contrast, post-mortem cardiac MR may be used to investigate coronary artery disease. Methods: We retrospectively compared autopsy and CT findings of 30 cases with significant (≥75%), insignificant (<75%), or absent coronary artery stenosis to post-mortem cardiac MR findings. The chi-square test was used to investigate if the occurrence of CSA depends on the presence or absence of stenosis. Sensitivity, specificity and predictive values were calculated for each finding. Results: CSA indicates the absence of (significant) stenosis (p < 0.001). The occurrence of paired dark bands in lieu of CSA on post-mortem cardiac MR suggests (significant) coronary arteries stenosis (p < 0.001). Both findings have a high specificity but low sensitivity. Conclusions: CSA is a marker of vessel patency. The presence of paired dark bands indicates stenosis. These criteria improve the ability of minimally invasive or virtual autopsy to detect coronary artery disease related deaths

Posttraumatic growth in post-surgical coronary artery bypass graft patients

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Catherine A Waight

2015-02-01

Full Text Available Recent research in posttraumatic growth has been applied to people with life-threatening illnesses to optimise recovery. There is a lack of research exploring posttraumatic growth in coronary artery bypass graft patients. This article describes the recovery experience of 14 coronary artery bypass graft patients (13 males and 1 female at their first outpatient review post-surgery. Grounded theory analysis was used to develop a model of distinct and shared pathways to growth depending on whether patients were symptomatic or asymptomatic pre-coronary artery bypass graft. Outcomes of posttraumatic growth in this sample included action-based healthy lifestyle growth and two forms of cognitive growth: appreciation of life and new possibilities. The model of posttraumatic growth developed in this study may be helpful in guiding future research into promoting posttraumatic growth and behaviour change in coronary artery bypass graft patients.

Clinical effectiveness of exogenous L-arginine in patients with coronary heart disease after community-acquired pneumonia

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T. O. Kulynych

2017-02-01

Full Text Available Coronary heart disease and community acquired pneumonia associated with a higher risk for morbidity and mortality. The optimization of treatment of comorbid pathology by medicines which modify endothelium functional state is important. Aim: to study effect of exogenous L-arginine on clinical course of disease, markers of systemic inflammation and endothelial dysfunction in patients with coronary heart disease (CHD and community-acquired pneumonia (CAP. Materials and methods. 60 patients with CHD and CAP (the median 72.50 years, range 66.00; 75.00 were included into the study. Patients were randomized in 2 groups: first – 30 patients with basic therapy combined with L-arginine; and second – 30 patients with basic therapy. hs-CRP, neopterin, РАРР-А, NT-proBNP were measured by ELISA-TEST before treatment and 1 month after. Clinical course was assessed during 1 year of follow-up. Results. In the first group the hospitalization rate due to CHD and heart failure decompensation was significantly rare. Biomarkers changes in the 1st group were significant: hs-CRP was significantly decreased by 57.14 % (in the 2nd group – by 28.57 %; neopterin – by 36.57 % (in the 2nd group – by 20.91 %; РАРР-А – by 35.71 % (in the 2nd group – by 4.76 %. There was revealed a significant decreasing of NT-proBNP levels in patients receiving L-arginine by comparing with basic therapy: with the I stage of heart failure (HF – by 50.97 % vs 21.82 %, with the II-A stage of HF – by 43.82 % vs 5.61 % (p < 0.05. After 1 month of therapy patients from the 1st group had significantly lower rates of neopterin – by 16.46 %, and NT-proBNP – by 40.92 % in the subgroup of patients with II-A stage of HF (p < 0.05 compared with patients who received only the basic therapy. Conclusions. Combination of exogenous L-arginine and basic therapy in patients with CHD and CAP was associated with benign clinical course and positive changes of endothelium functional

Inversion prepared coronary MR angiography: direct visualization of coronary blood flow

International Nuclear Information System (INIS)

Katoh, M.; Spuentrup, E.; Buecker, A.; Guenther, R.W.; Stuber, M.; Manning, W.J.; Botnar, R.M.

2005-01-01

Purpose: visualization of coronary blood flow by means of a slice-selective inversion pre-pulse in concert with bright-blood coronary MRA. Materials and methods: coronary magnetic resonance angiography (MRA) of the right coronary artery (RCA) was performed in eight healthy adult subjects on a 1.5 Tesla MR system (Gyroscan ACS-NT, Philips Medical Systems, Best, NL) using a free-breathing navigator-gated and cardiac-triggered 3D steady-state free-precession (SSFP) sequence with radial k-space sampling. Imaging was performed with and without a slice-selective inversion pre-pulse, which was positioned along the main axis of the coronary artery but perpendicular to the imaging volume. Objective image quality parameters such as SNR, CNR, maximal visible vessel length, and vessel border definition were analyzed. Results: in contrast to conventional bright-blood 3D coronary MRA, the selective inversion pre-pulse provided a direct measure of coronary blood flow. In addition, CNR between the RCA and right ventricular blood pool was increased and the vessels had a tendency towards better delineation. Blood SNR and CNR between right coronary blood and epicardial fat were comparable in both sequences. (orig.)

The Anti-Apoptotic Properties of APEX1 in the Endothelium Require the First 20 Amino Acids and Converge on Thioredoxin-1.

Science.gov (United States)

Dyballa-Rukes, Nadine; Jakobs, Philipp; Eckers, Anna; Ale-Agha, Niloofar; Serbulea, Vlad; Aufenvenne, Karin; Zschauer, Tim-Christian; Rabanter, Lothar L; Jakob, Sascha; von Ameln, Florian; Eckermann, Olaf; Leitinger, Norbert; Goy, Christine; Altschmied, Joachim; Haendeler, Judith

2017-04-20

The APEX nuclease (multifunctional DNA repair enzyme) 1 (APEX1) has a disordered N-terminus, a redox, and a DNA repair domain. APEX1 has anti-apoptotic properties, which have been linked to both domains depending on cell type and experimental conditions. As protection against apoptosis is a hallmark of vessel integrity, we wanted to elucidate whether APEX1 acts anti-apoptotic in primary human endothelial cells and, if so, what the underlying mechanisms are. APEX1 inhibits apoptosis in endothelial cells by reducing Cathepsin D (CatD) cleavage, potentially by binding to the unprocessed form. Diminished CatD activation results in increased Thioredoxin-1 protein levels leading to reduced Caspase 3 activation. Consequently, apoptosis rates are decreased. This depends on the first twenty amino acids in APEX1, because APEX1 (21-318) induces CatD activity, decreases Thioredoxin-1 protein levels, and, thus, increases Caspase 3 activity and apoptosis. Along the same lines, APEX1 (1-20) inhibits Caspase 3 cleavage and apoptosis. Furthermore, re-expression of Thioredoxin-1 via lentiviral transduction rescues endothelial cells from APEX1 (21-318)-induced apoptosis. In an in vivo model of restenosis, which is characterized by oxidative stress, endothelial activation, and smooth muscle cell proliferation, Thioredoxin-1 protein levels are reduced in the endothelium of the carotids. APEX1 acts anti-apoptotic in endothelial cells. This anti-apoptotic effect depends on the first 20 amino acids of APEX1. As proper function of the endothelium during life span is a hallmark for individual health span, a detailed characterization of the functions of the APEX1N-terminus is required to understand all its cellular properties. Antioxid. Redox Signal. 26, 616-629.

Coronary Artery Anomalies in Animals

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Brian A. Scansen

2017-04-01

Full Text Available Coronary artery anomalies represent a disease spectrum from incidental to life-threatening. Anomalies of coronary artery origin and course are well-recognized in human medicine, but have received limited attention in veterinary medicine. Coronary artery anomalies are best described in the dog, hamster, and cow though reports also exist in the horse and pig. The most well-known anomaly in veterinary medicine is anomalous coronary artery origin with a prepulmonary course in dogs, which limits treatment of pulmonary valve stenosis. A categorization scheme for coronary artery anomalies in animals is suggested, dividing these anomalies into those of major or minor clinical significance. A review of coronary artery development, anatomy, and reported anomalies in domesticated species is provided and four novel canine examples of anomalous coronary artery origin are described: an English bulldog with single left coronary ostium and a retroaortic right coronary artery; an English bulldog with single right coronary ostium and transseptal left coronary artery; an English bulldog with single right coronary ostium and absent left coronary artery with a prepulmonary paraconal interventricular branch and an interarterial circumflex branch; and a mixed-breed dog with tetralogy of Fallot and anomalous origin of all coronary branches from the brachiocephalic trunk. Coronary arterial fistulae are also described including a coronary cameral fistula in a llama cria and an English bulldog with coronary artery aneurysm and anomalous shunting vessels from the right coronary artery to the pulmonary trunk. These examples are provided with the intent to raise awareness and improve understanding of such defects.

Activation of the Arterial Program Drives Development of Definitive Hemogenic Endothelium with Lymphoid Potential

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Mi Ae Park

2018-05-01

Full Text Available Summary: Understanding the pathways guiding the development of definitive hematopoiesis with lymphoid potential is essential for advancing human pluripotent stem cell (hPSC technologies for the treatment of blood diseases and immunotherapies. In the embryo, lymphoid progenitors and hematopoietic stem cells (HSCs arise from hemogenic endothelium (HE lining arteries but not veins. Here, we show that activation of the arterial program through ETS1 overexpression or by modulating MAPK/ERK signaling pathways at the mesodermal stage of development dramatically enhanced the formation of arterial-type HE expressing DLL4 and CXCR4. Blood cells generated from arterial HE were more than 100-fold enriched in T cell precursor frequency and possessed the capacity to produce B lymphocytes and red blood cells expressing high levels of BCL11a and β-globin. Together, these findings provide an innovative strategy to aid in the generation of definitive lymphomyeloid progenitors and lymphoid cells from hPSCs for immunotherapy through enhancing arterial programming of HE. : Park et al. find that activation of the arterial program through ETS1 overexpression or by modulating MAPK/ERK signaling pathways at the mesodermal stage of development dramatically enhances formation of arterial-type hemogenic endothelium (HE from hPSCs. Blood cells generated from arterial HE are highly enriched in definitive lymphomyeloid progenitors. Keywords: human pluripotent stem cells, hemogenic endothelium, T cells, hematopoietic stem cells, hematopoiesis, ETS1, MAPK/ERK signaling

SH2 domain-containing protein tyrosine phosphatase 2 and focal adhesion kinase protein interactions regulate pulmonary endothelium barrier function.

Science.gov (United States)

Chichger, Havovi; Braza, Julie; Duong, Huetran; Harrington, Elizabeth O

2015-06-01

Enhanced protein tyrosine phosphorylation is associated with changes in vascular permeability through formation and dissolution of adherens junctions and regulation of stress fiber formation. Inhibition of the protein tyrosine phosphorylase SH2 domain-containing protein tyrosine phosphatase 2 (SHP2) increases tyrosine phosphorylation of vascular endothelial cadherin and β-catenin, resulting in disruption of the endothelial monolayer and edema formation in the pulmonary endothelium. Vascular permeability is a hallmark of acute lung injury (ALI); thus, enhanced SHP2 activity offers potential therapeutic value for the pulmonary vasculature in diseases such as ALI, but this has not been characterized. To assess whether SHP2 activity mediates protection against edema in the endothelium, we assessed the effect of molecular activation of SHP2 on lung endothelial barrier function in response to the edemagenic agents LPS and thrombin. Both LPS and thrombin reduced SHP2 activity, correlated with decreased focal adhesion kinase (FAK) phosphorylation (Y(397) and Y(925)) and diminished SHP2 protein-protein associations with FAK. Overexpression of constitutively active SHP2 (SHP2(D61A)) enhanced baseline endothelial monolayer resistance and completely blocked LPS- and thrombin-induced permeability in vitro and significantly blunted pulmonary edema formation induced by either endotoxin (LPS) or Pseudomonas aeruginosa exposure in vivo. Chemical inhibition of FAK decreased SHP2 protein-protein interactions with FAK concomitant with increased permeability; however, overexpression of SHP2(D61A) rescued the endothelium and maintained FAK activity and FAK-SHP2 protein interactions. Our data suggest that SHP2 activation offers the pulmonary endothelium protection against barrier permeability mediators downstream of the FAK signaling pathway. We postulate that further studies into the promotion of SHP2 activation in the pulmonary endothelium may offer a therapeutic approach for patients

CAD-RADS - a new clinical decision support tool for coronary computed tomography angiography.

Science.gov (United States)

Foldyna, Borek; Szilveszter, Bálint; Scholtz, Jan-Erik; Banerji, Dahlia; Maurovich-Horvat, Pál; Hoffmann, Udo

2018-04-01

Coronary computed tomography angiography (CTA) has been established as an accurate method to non-invasively assess coronary artery disease (CAD). The proposed 'Coronary Artery Disease Reporting and Data System' (CAD-RADS) may enable standardised reporting of the broad spectrum of coronary CTA findings related to the presence, extent and composition of coronary atherosclerosis. The CAD-RADS classification is a comprehensive tool for summarising findings on a per-patient-basis dependent on the highest-grade coronary artery lesion, ranging from CAD-RADS 0 (absence of CAD) to CAD-RADS 5 (total occlusion of a coronary artery). In addition, it provides suggestions for clinical management for each classification, including further testing and therapeutic options. Despite some limitations, CAD-RADS may facilitate improved communication between imagers and patient caregivers. As such, CAD-RADS may enable a more efficient use of coronary CTA leading to more accurate utilisation of invasive coronary angiograms. Furthermore, widespread use of CAD-RADS may facilitate registry-based research of diagnostic and prognostic aspects of CTA. • CAD-RADS is a tool for standardising coronary CTA reports. • CAD-RADS includes clinical treatment recommendations based on CTA findings. • CAD-RADS has the potential to reduce variability of CTA reports.

Serum galectin-2, -4, and -8 are greatly increased in colon and breast cancer patients and promote cancer cell adhesion to blood vascular endothelium

DEFF Research Database (Denmark)

Barrow, Hannah; Guo, Xiuli; Wandall, Hans H

2011-01-01

Adhesion of disseminating tumor cells to the blood vascular endothelium is a pivotal step in metastasis. Previous investigations have shown that galectin-3 concentrations are increased in the bloodstream of patients with cancer and that galectin-3 promotes adhesion of disseminating tumor cells...... to vascular endothelium in vitro and experimental metastasis in vivo. This study determined the levels of galectin-1, -2, -3, -4, -8, and -9 in the sera of healthy people and patients with colon and breast cancer and assessed the influence of these galectins on cancer-endothelium adhesion....

Vascular endothelium receptors and transduction mechanisms

CERN Document Server

Gillis, C; Ryan, Una; Proceedings of the Advanced Studies Institute on "Vascular Endothelium: Receptors and Transduction Mechanisms"

1989-01-01

Beyond their obvious role of a barrier between blood and tissue, vascular endothelial cells are now firmly established as active and essential participants in a host of crucial physiological and pathophysiological functions. Probably the two most important factors responsible for promoting the current knowledge of endothelial functions are 1) observations in the late sixties-early seventies that many non-ventilatory properties of the lung could be attributed to the pulmonary endothelium and 2) the establishment, in the early and mid-seventies of procedures for routine culture of vascular endothelial cells. Many of these endothelial functions require the presence of receptors on the surface of the plasma membrane. There is now evidence for the existence among others of muscarinic, a-and /3-adrenergic, purine, insulin, histamine, bradykinin, lipoprotein, thrombin, paf, fibronectin, vitronectin, interleukin and albumin receptors. For some of these ligands, there is evidence only for the existence of endothelial ...

Ulex europaeus I lectin as a marker for vascular endothelium in human tissues.

Science.gov (United States)

Holthöfer, H; Virtanen, I; Kariniemi, A L; Hormia, M; Linder, E; Miettinen, A

1982-07-01

Ulex europaeus I agglutinin, a lectin specific for some alpha-L-fucose-containing glycocompounds, was used in fluorescence microscopy to stain cryostat sections of human tissues. The endothelium of vessels of all sizes was stained ubiquitously in all tissues studied as judged by double staining with a known endothelial marker, antibodies against human clotting factor VIII. Cultured human umbilical vein endothelial cells, but not fibroblasts, also bound Ulex lectin. The staining was not affected by the blood group type of the tissue donor. In some tissues Ulex lectin presented additional binding to epithelial structures. Also, this was independent on the blood group or the ability of the tissue donor to secrete soluble blood group substances. Lotus tetragonolobus agglutinin, another lectin specific for some alpha-L-fucose-containing moieties failed to react with endothelial cells. Our results suggest that Ulex europaeus I agglutinin is a good histologic marker for endothelium in human tissues.

Opening of small and intermediate calcium-activated potassium channels induces relaxation mainly mediated by nitric-oxide release in large arteries and endothelium-derived hyperpolarizing factor in small arteries from rat

DEFF Research Database (Denmark)

Stankevicius, Edgaras; Dalsgaard, Thomas; Kroigaard, Christel

2011-01-01

This study was designed to investigate whether calcium-activated potassium channels of small (SK(Ca) or K(Ca)2) and intermediate (IK(Ca) or K(Ca)3.1) conductance activated by 6,7-dichloro-1H-indole-2,3-dione 3-oxime (NS309) are involved in both nitric oxide (NO) and endothelium-derived hyperpolar......This study was designed to investigate whether calcium-activated potassium channels of small (SK(Ca) or K(Ca)2) and intermediate (IK(Ca) or K(Ca)3.1) conductance activated by 6,7-dichloro-1H-indole-2,3-dione 3-oxime (NS309) are involved in both nitric oxide (NO) and endothelium...... in human umbilical vein endothelial cells (HUVECs), and calcium concentrations were investigated in both HUVECs and mesenteric arterial endothelial cells. In both superior (∼1093 μm) and small mesenteric (∼300 μm) arteries, NS309 evoked endothelium- and concentration-dependent relaxations. In superior....... In small mesenteric arteries, NS309 relaxations were reduced slightly by ADMA, whereas apamin plus an IK(Ca) channel blocker almost abolished relaxation. Iberiotoxin did not change NS309 relaxation. HUVECs expressed mRNA for SK(Ca) and IK(Ca) channels, and NS309 induced increases in calcium, outward...

Takayasu Arteritis of the Coronary Arteries Presenting as Sudden Death in a White Teenager.

Science.gov (United States)

Hlavaty, Leigh; Diaz, Francisco; Sung, LokMan

2015-09-01

Takayasu arteritis is a rare disease that expresses chronic, large vessel inflammation. The etiology remains unclear and its presentation depends on the affected arteries. With coronary artery involvement, manifestations range from chest pain and shortness of breath to sudden death. We report a case of a 15-year-old white girl who presented with syncope immediately before passing. On autopsy, all 3 major coronary arteries grossly contained multiple proximal lesions that were consistent with Takayasu arteritis, microscopically. Takayasu arteritis solely affecting multiple coronary arteries is exceedingly rare. This report discusses the significance of coronary involvement in Takayasu arteritis at autopsy and sudden death.

Activation of the sweet taste receptor, T1R3, by the artificial sweetener sucralose regulates the pulmonary endothelium.

Science.gov (United States)

Harrington, Elizabeth O; Vang, Alexander; Braza, Julie; Shil, Aparna; Chichger, Havovi

2018-01-01

A hallmark of acute respiratory distress syndrome (ARDS) is pulmonary vascular permeability. In these settings, loss of barrier integrity is mediated by cell-contact disassembly and actin remodeling. Studies into molecular mechanisms responsible for improving microvascular barrier function are therefore vital in the development of therapeutic targets for reducing vascular permeability in ARDS. The sweet taste receptor T1R3 is a G protein-coupled receptor, activated following exposure to sweet molecules, to trigger a gustducin-dependent signal cascade. In recent years, extraoral locations for T1R3 have been identified; however, no studies have focused on T1R3 within the vasculature. We hypothesize that activation of T1R3, in the pulmonary vasculature, plays a role in regulating endothelial barrier function in settings of ARDS. Our study demonstrated expression of T1R3 within the pulmonary vasculature, with a drop in expression levels following exposure to barrier-disruptive agents. Exposure of lung microvascular endothelial cells to the intensely sweet molecule sucralose attenuated LPS- and thrombin-induced endothelial barrier dysfunction. Likewise, sucralose exposure attenuated bacteria-induced lung edema formation in vivo. Inhibition of sweet taste signaling, through zinc sulfate, T1R3, or G-protein siRNA, blunted the protective effects of sucralose on the endothelium. Sucralose significantly reduced LPS-induced increased expression or phosphorylation of the key signaling molecules Src, p21-activated kinase (PAK), myosin light chain-2 (MLC2), heat shock protein 27 (HSP27), and p110α phosphatidylinositol 3-kinase (p110αPI3K). Activation of T1R3 by sucralose protects the pulmonary endothelium from edemagenic agent-induced barrier disruption, potentially through abrogation of Src/PAK/p110αPI3K-mediated cell-contact disassembly and Src/MLC2/HSP27-mediated actin remodeling. Identification of sweet taste sensing in the pulmonary vasculature may represent a novel

High-Throughput Screening of Vascular Endothelium-Destructive or Protective Microenvironments: Cooperative Actions of Extracellular Matrix Composition, Stiffness, and Structure.

Science.gov (United States)

Ding, Yonghui; Floren, Michael; Tan, Wei

2017-06-01

Pathological modification of the subendothelial extracellular matrix (ECM) has closely been associated with endothelial activation and subsequent cardiovascular disease progression. To understand regulatory mechanisms of these matrix modifications, the majority of previous efforts have focused on the modulation of either chemical composition or matrix stiffness on 2D smooth surfaces without simultaneously probing their cooperative effects on endothelium function on in vivo like 3D fibrous matrices. To this end, a high-throughput, combinatorial microarray platform on 2D and 3D hydrogel settings to resemble the compositions, stiffness, and structure of healthy and diseased subendothelial ECM has been established, and further their respective and combined effects on endothelial attachment, proliferation, inflammation, and junctional integrity have been investigated. For the first time, the results demonstrate that 3D fibrous structure resembling native ECM is a critical endothelium-protective microenvironmental factor by maintaining the stable, quiescent endothelium with strong resistance to proinflammatory stimuli. It is also revealed that matrix stiffening, in concert with chemical compositions resembling diseased ECM, particularly collagen III, could aggravate activation of nuclear factor kappa B, disruption of endothelium integrity, and susceptibility to proinflammatory stimuli. This study elucidates cooperative effects of various microenvironmental factors on endothelial activation and sheds light on new in vitro model for cardiovascular diseases. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Diagnosing coronary artery disease after a positive coronary computed tomography angiography

DEFF Research Database (Denmark)

Nissen, L; Winther, S; Westra, J

2018-01-01

Aims: Perfusion scans after coronary computed tomography angiography (CCTA) in patients with suspected coronary artery disease (CAD) may reduce unnecessary invasive coronary angiographies (ICAs). However, the diagnostic accuracy of perfusion scans after primary CCTA is unknown. The aim...

The association of opium dependence and postoperative complications following coronary artery bypass graft surgery: a propensity-matched study.

Science.gov (United States)

Sadeghian, Saeed; Karimi, Abbasali; Dowlatshahi, Samaneh; Ahmadi, Seyed Hossein; Davoodi, Saeed; Marzban, Mehrab; Movahedi, Namvar; Abbasi, Kyomars; Tazik, Mokhtar; Fathollahi, Mahmood Sheikh

2009-01-01

Opium is an overwhelming public health problem in some countries. Different studies have suggested this drug as a risk factor for cardiovascular disease. Although the effect of opium on immune system, lung disease, nephropathy, stroke, and cardiac arrhythmia has been found in different studies, its effect on postoperation complications is not clear yet. The authors conducted this study to assess the effect of opium on post operation in hospital complications among patients who underwent coronary artery bypass graft. The authors retrospectively analyzed the data in this study. This study has been done at Tehran Heart Center. A total of 4,398 patients who had undergone isolated CABG were studied. Patients who fulfilled the DSM-IV-TR criteria for opium dependence (by smoking) were enrolled as Opium Dependent Patients. Also outcome variables were: Perioperative MI, septicemia, UTI, TIA, continuous coma, prolonged ventilation, pulmonary embolism, renal failure, acute limb ischemia, heart block, AF, mortality. The prevalence of opium dependence was 15.6percent among patients. The authors used a propensity matched model to analyze the relationship between opium and post operation complications. The authors adjusted opium and non-opium dependent patients in all of the baseline preoperative risk factors, so all of the matched patients were same and there was no bias in assessment. Opium dependent patients had significantly longer resource utilization. However, no significant relationship was found between opium dependence and other cardiac and non cardiac in hospital complications.

Non-obstructive coronary artery disease assessed by coronary computed tomography angiography

DEFF Research Database (Denmark)

Nielsen, L.; Bøtker, H. E.; Sorensen, H.

2015-01-01

Introduction: Coronary CT angiography (CTA) detects non-obstructive coronary artery disease (CAD) that may not be recognized by functional testing, but the prognostic impact is not well understood. This study aimed to compare the risk of myocardial infarction (MI) and all-cause mortality...... in patients without or with non-obstructive and obstructive CAD assessed by coronary CTA. Methods: Consecutive patients without known coronary artery disease (CAD) and with chest pain who underwent coronary CTA (>64-detector row) between January 2007 and December 2012 in the 10 centers participating...... in the Western Denmark Cardiac Computed Tomography Registry were included. The endpoints were 3-year MI or all-cause mortality. The coronary CTA result was defined as normal (0% luminal stenosis), non-obstructive CAD (1%-49% luminal stenosis) or obstructive CAD (>50% luminal stenosis; 1-vessel, 2-vessel, or 3...

Coronary artery bypass surgery in the diabetic patient.

LENUS (Irish Health Repository)

Maher, M

2012-02-03

Coronary artery and peripheral occlusive arterial disease frequently complicate diabetes mellitus, with death due to atherosclerotic coronary artery disease being three times more likely in diabetic compared to non-diabetic patients. The profile of 32 diabetic patients and 32 matched controls who underwent coronary artery bypass (CABG) is studied and their early and late postoperative outcomes are described. The mean age was 61 +\\/- 1 year in both groups. The diabetic group comprised 26 non-insulin dependent and 6 insulin dependent diabetics, who had a mean duration of diabetes of 8.5 years (range 2 months--35 years). The median number of grafts per patient performed in the diabetic group and the control group was 3.5 and 3 respectively. There was no mortality in the series, however considerably greater wound morbidity rates were encountered in the diabetic group when compared to matched controls. One renal transplant patient in the diabetic group suffered irreversible acute tubular necrosis and became dialysis dependent post-operatively. Longterm follow-up showed no longterm mortality in either group, with full relief of angina achieved in 75% of diabetic patients compared with 87.5% of matched controls. In addition diabetic patients suffered greater longterm cardiac morbidity than the control group (21.8% versus 12.5%). The results of this study suggest that CABG is a safe operation for the diabetic patient. Diabetic patients receive satisfactory symptomatic relief of angina, but suffer increased perioperative wound complications and greater incidence of longterm cardiac morbidity.

Coronary hemodynamics in vasospastic angina

International Nuclear Information System (INIS)

Matsumura, Kentaro; Kubota, Shinobu; Serizawa, Takashi; Nakase, Emiko; Kawai, Ichiro; Saito, Takayuki

1991-01-01

To evaluate the coronary circulation and myocardial perfusion dynamics, we performed left coronary digital subtraction angiography (DSA) in 35 patients with vasospastic angina. The left coronary circulation time (CCT) measured from the proximal left coronary artery to the coronary sinus was 5.77±0.86 sec, and the left epicardial conducting artery transmission time (CAT) measured from the proximal left coronary artery to the apical area was 2.65±0.82 sec in normal controls. The CCT and CAT were significantly prolonged in patients with vasospastic angina, indicating that the coronary peripheral vascular resistance is probably greater after the cessation of nitrates and Ca ++ -antagonists. After the intracoronary injection of ergonovine malate, the CCT was slightly shortened, but the apical T 1/2 was significantly prolonged in patients with vasospastic angina. This suggested that coronary vasospasm is present not only in the epicardial arteries but also in coronary arteries with peripheral resistance. These phenomena were not observed in normal controls. We performed left coronary DSA after conventional left coronary cineangiography. When the CCT exceeded 6.7 sec, we considered that the coronary circulation was significantly impaired. We concluded that the coronary DSA is very useful for evaluating abnormal coronary circulation in patients with vasospastic angina during myocardial perfusion. (author)

Speculative Considerations about Some Cardiology Enigmas.

Science.gov (United States)

Evora, Paulo Roberto Barbosa; Schmidt, Andre; Arcêncio, Livia; Marin-Neto, José Antonio

2017-01-01

Enigmas often lead to hypotheses and speculations. For this reason, especially for the sake of the reader's motivation, we opted for the plain discussion of some cardiology enigmas. The present text was aimed to discuss speculatively some cardiology enigmas. Text was freely designed in the context of coronary artery and heart valve diseases. The results were presented as the combination enigma/hypothesis. 1) The absence of arteriosclerosis in intramyocardial coronary arteries/ endothelium-myocardial interaction (crosstalk); 2) The unique and always confirmed superior evolution of the internal thoracic artery as coronary graft/ higher NO basal release 3) The prophylactic left internal thoracic artery graft in mildlystenosed coronary lesions/need of more accurate functional imaging techniques; 4) The high incidence of perioperative atrial fibrillation in patients with coronary artery disease/atrial ischemia associated to left circumflex coronary lesions; 5) The handling of disease-free saphenous vein grafts at the time of reoperation/biological serendipity with graft vein segments; 6) The possible aortic stenosis protection against coronary artery disease/ endothelium-myocardium interaction (crosstalk) improving NO release. The discussed topics associated with their respective speculative hypothesis remain as enigmas, but would become motivations for investigations. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Jabuticaba-Induced Endothelium-Independent Vasodilating Effect on Isolated Arteries.

Science.gov (United States)

Andrade, Daniela Medeiros Lobo de; Borges, Leonardo Luis; Torres, Ieda Maria Sapateiro; Conceição, Edemilson Cardoso da; Rocha, Matheus Lavorenti

2016-09-01

Despite the important biological effects of jabuticaba, its actions on the cardiovascular system have not been clarified. To determine the effects of jabuticaba hydroalcoholic extract (JHE) on vascular smooth muscle (VSM) of isolated arteries. Endothelium-denuded aortic rings of rats were mounted in isolated organ bath to record isometric tension. The relaxant effect of JHE and the influence of K+ channels and Ca2+ intra- and extracellular sources on JHE-stimulated response were assessed. Arteries pre-contracted with phenylephrine showed concentration-dependent relaxation (0.380 to 1.92 mg/mL). Treatment with K+ channel blockers (tetraethyl-ammonium, glibenclamide, 4-aminopyridine) hindered relaxation due to JHE. In addition, phenylephrine-stimulated contraction was hindered by previous treatment with JHE. Inhibition of sarcoplasmic reticulum Ca2+ ATPase did not change relaxation due to JHE. In addition, JHE inhibited the contraction caused by Ca2+ influx stimulated by phenylephrine and KCl (75 mM). JHE induces endothelium-independent vasodilation. Activation of K+ channels and inhibition of Ca2+ influx through the membrane are involved in the JHE relaxant effect. Embora a jabuticaba apresente importantes efeitos biológicos, suas ações sobre o sistema cardiovascular ainda não foram esclarecidas. Determinar os efeitos do extrato de jabuticaba (EHJ) sobre o músculo liso vascular (MLV) em artérias isoladas. Aortas (sem endotélio) de ratos foram montadas em banho de órgãos isolados para registro de tensão isométrica. Foram verificados o efeito relaxante, a influência dos canais de K+ e das fontes de Ca2+ intra- e extracelular sob a resposta estimulada pelo EHJ. Artérias pré-contraídas com fenilefrina apresentaram relaxamento concentração-dependente (0,380 a 1,92 mg/mL). O tratamento com bloqueadores de canais de K+ (tetraetilamônio, glibenclamida, 4-aminopiridina) prejudicaram o relaxamento pelo EHJ. A contração estimulada com fenilefrina tamb

Detecting asymptomatic coronary artery disease using routine ...

African Journals Online (AJOL)

ECG-monitored exercise testing has been proposed as a relatively inexpensive and effective means of screening for asymptomatic coronary artery disease in patients presenting for peripheral vascular surgery. Despite the fact that exercise thallium scintigraphy is also dependent on the patient's ability to exercise, using this ...

Coronary artery fistulas as a cause of angina: How to manage these patients?

Energy Technology Data Exchange (ETDEWEB)

Buccheri, Dario; Dendramis, Gregory, E-mail: gregorydendramis@libero.it; Piraino, Davide; Chirco, Paola Rosa; Carità, Patrizia; Paleologo, Claudia; Andolina, Giuseppe; Assennato, Pasquale; Novo, Salvatore

2015-07-15

Coronary artery fistulas represent the most common hemodynamically significant congenital defect of the coronary arteries and the clinical presentation is mainly dependent on the severity of the left-to-right shunt. We describe a case of a 55-year-old man with history of chest pain and without history of previous significant chest wall trauma or any invasive cardiac procedures. A coronary multislice computed tomography showed two large coronary fistulas arising from the left anterior descending coronary artery and ending in an angiomatous plexus draining into the common pulmonary trunk. Coronary angiography confirmed the CT finding and showed a third fistulous communication arising from the sinus node artery. Although coronary fistulas are infrequent, they are becoming increasingly important because their management and treatment could prevent serious complications. The latest guidelines of the American College of Cardiology/American Heart Association indicate as Class I recommendation the percutaneous or surgical closure for large fistulas regardless of symptoms. In this manuscript, we provide a detailed review of the literature on this topic, focusing on the clinical management of these patients.

Early results of coronary artery bypass grafting with coronary endarterectomy for severe coronary artery disease

Directory of Open Access Journals (Sweden)

Toischer Karl

2009-09-01

Full Text Available Abstract Background Despite the existence of controversial debates on the efficiency of coronary endarterectomy (CE, it is still used as an adjunct to coronary artery bypass grafting (CABG. This is particularly true in patients with endstage coronary artery disease. Given the improvements in cardiac surgery and postoperative care, as well as the rising number of elderly patient with numerous co-morbidities, re-evaluating the pros and cons of this technique is needed. Methods Patient demographic information, operative details and outcome data of 104 patients with diffuse calcified coronary artery disease were retrospectively analyzed with respect to functional capacity (NYHA, angina pectoris (CCS and mortality. Actuarial survival was reported using a Kaplan-Meyer analysis. Results Between August 2001 and March 2005, 104 patients underwent coronary artery bypass grafting (CABG with adjunctive coronary endarterectomy (CE in the Department of Thoracic-, Cardiac- and Vascular Surgery, University of Goettingen. Four patients were lost during follow-up. Data were gained from 88 male and 12 female patients; mean age was 65.5 ± 9 years. A total of 396 vessels were bypassed (4 ± 0.9 vessels per patient. In 98% left internal thoracic artery (LITA was used as arterial bypass graft and a total of 114 vessels were endarterectomized. CE was performed on right coronary artery (RCA (n = 55, on left anterior descending artery (LAD (n = 52 and circumflex artery (RCX (n = 7. Ninety-five patients suffered from 3-vessel-disease, 3 from 2-vessel- and 2 from 1-vessel-disease. Closed technique was used in 18%, open technique in 79% and in 3% a combination of both. The most frequent endarterectomized localization was right coronary artery (RCA = 55%. Despite the severity of endstage atherosclerosis, hospital mortality was only 5% (n = 5. During follow-up (24.5 ± 13.4 months, which is 96% complete (4 patients were lost caused by unknown address 8 patients died (cardiac

Use of postmortem coronary computed tomography angiography with water-insoluble contrast medium to detect stenosis of the left anterior descending artery in a case of sudden death.

Science.gov (United States)

Takahashi, Yoichiro; Sano, Rie; Takahashi, Keiko; Kominato, Yoshihiko; Takei, Hiroyuki; Kobayashi, Susumu; Shimada, Takehiro; Tokue, Hiroyuki; Awata, Sachiko; Hirasawa, Satoshi

2016-03-01

A 40-year-old man was found dead on a sidewalk in an expressway parking area one hour after he had entered the area on a motorcycle. A medicolegal autopsy was performed to reveal the cause of this sudden and unexpected death. Postmortem coronary CT angiography after introduction of 5% gelatin-barium emulsion as a radiopaque contrast medium into the heart demonstrated a significant arterial luminal filling defect in the left anterior descending (LAD) coronary artery. Macroscopic and microscopic examinations revealed that a thrombus had become deposited on ruptured plaque within the LAD artery, and that a small amount of the contrast medium was present between the thrombus and the vessel endothelium. These histological findings were consistent with incomplete occlusion of the LAD artery in the 3D reconstructed image. The cause of death in this case was definitively determined to be ischemic heart disease. Postmortem angiography played a role in screening of a vascular lesion that was subsequently verified by histology to have been responsible for sudden and unexpected death. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

[Comparison of 64 MDCT coronary CTA and coronary angiography in the detection of coronary artery stenosis in low risk patients with stable angina and acute coronary syndrome].

Science.gov (United States)

Cazalas, G; Sarran, A; Amabile, N; Chaumoitre, K; Marciano-Chagnaud, S; Jacquier, A; Paganelli, F; Panuel, M

2009-09-01

To determine the accuracy of 64 MDCT coronary CTA (CCTA) compared to coronary angiography in low risk patients with stable angina and acute coronary syndrome and determine the number of significant coronary artery stenoses ( 50%) in these patients. Materials and methods. Fifty-five patients underwent CCTA using a 32 MDCT unit with z flying focus allowing the acquisition of 64 slices of 0.6 mm thickness as well as coronary angiography (gold standard). Nine patients were excluded due to prior coronary artery bypass surgery (n=4), insufficient breath hold (n=3), calcium scoring>1000 (n=1) and delay between both examinations over 4 months (n=1). Forty-six patients: 27 males and 19 females were included. CCTA results were compared to coronary angiography per segment and artery with threshold detection of stenoses 50%. The degree of correlation between both examinations was performed using a regression analysis with a Pearson correlation coefficient<0.05 considered significant. The overall accuracy of CCTA was 90%; limitations related to the presence of calcifications, motion artifacts or insufficient vessel opacification. The correlation for all analyzed segments was 96.4%. Thirty-eight of 50 significant stenoses seen on coronary angiography were correctly detected on CCTA. Sensitivity, specificity, PPVC and NPV for detection of stenoses 50% were 76%, 98.3%, 80.3% and 97.7% respectively. Evaluation per segment had a NPV of 96.8% (interventricular and diagonal segments) to 100% (main trunk). Our results for specificity and NPV are similar to reports from the literature. This suggests that CCTA in this clinical setting may replace coronary angiography.

Morphological study on coronary ostial and clinicoangiographic analysis of isolated coronary ostial stenosis

International Nuclear Information System (INIS)

Kanoh, Tatsuji

2007-01-01

A morphological study of coronary ostia was performed in 70 autopsied human hearts, with particular attention being focused on the funnel-shaped structure, aging changes, and relation to atherosclerosis. The following results were obtained: The ostium is particularly well-defined and forms a funnel-shaped structure. The structure is predominantly a double circular shape on the right and comet-shaped on the left. The funnel-shaped structure of coronary ostia is characterized by a longitudinal smooth muscle arrangement in the inner layer and circular one in the outer layer. Including overhang formation, coronary sclerosis of the ostium appears mainly on the upper margin of the funnel-shaped structure of the right ostium and at the upper right margin of the left. In ischemic heart disease, along with changes in coronary arteries themselves, changes in the ostia of these arteries should be paid close attention. Ostial stenosis of the coronary artery in the absence of distal vessel obstructions, isolated ostial stenosis, is a rare form of coronary artery disease. In a previous review of the international literature, the incidence of coronary ostial stenosis varied between 0.13% and 2.7%. Among 7,500 patients undergoing selective coronary cineangiography at Juntendo University Hospital and Juntendo Urayasu Hospital from 1975 to 1990, five women (0.07%) were diagnosed as having ''isolated coronary ostial stenosis'', of which the cause is unknown. Atherosclerosis, particularly early premature atherome, congenital coronary anomaly, fibro-muscular dysplasia, Takayasu's aortitis, humoral factors, spasm, and iatrogenic events have been considered as its causes. In contrast to usual atherosclerotic coronary artery disease, patients with isolated coronary ostial stenosis of unknown etiology were characterized as being middle-aged, premenopausal, slender females having few coronary risk factors, experiencing severe angina pector is with marked ischemic electrocardiogram changes

Factors influencing delay time and coronary arterial density during coronary angiography with DSCT.

Science.gov (United States)

Tang, Lijun; Zhu, Xiaomei; Xu, Yi; Yu, Tongfu; Xu, Hai; Tang, Jinhua; Dogra, Vikram; Wang, Dehang

2011-02-01

CT angiography (CTA) plays an important role in diagnosing coronary arterial disease. Delay time and density of the coronary arteries related with patient-specific factors are essential for getting an optimal CTA image. To investigate various factors influencing delay time and coronary arterial density during coronary CTA with dual source CT. One hundred and sixteen consecutive subjects who underwent cardiac DSCT with retrospective ECG-gating were included. Factors including gender, age, height, weight, transversal cardiac diameter (TCD), transversal thoracic diameter (TTD), heart rate (HR), body surface area (BSA = [weight × height/3600](1/2)) and cardiothoracic ratio (CTR = TCD/TTD) were recorded, measured and calculated before administration of contrast media during coronary CT angiography. Delay time was determined as duration from the beginning of the injection to the density in the descending aorta at the level of right main pulmonary artery reaching a threshold of 100 HU. Coronary arterial density was measured at the mid portion of the right coronary artery. Regression analysis and stepwise regression analysis were used to investigate the influence of these factors on delay time and coronary arterial density. Delay time decreased with an increasing HR and it was shorter in women than men. Delay time increased with an increasing TCD. Delay time could be predicted by the formula: DT = 16.651-0.110 × HR + 1.902 × gender + 0.394 × TCD (where DT is abbreviation for delay time, gender is 0 for women and 1 for men). Coronary arterial density decreased with an increasing HR and weight. Coronary arterial density could be predicted by the formula: CAD = 923.42-4.099 × HR-3.293 × weight (CAD = coronary arterial density). There was no relationship between the other factors mentioned above and delay time or coronary arterial density. Delay time is influenced by HR, gender and TCD. Coronary arterial density also changes with HR and weight. So HR, gender, TCD and

Myocardial flow reserve is influenced by both coronary artery stenosis severity and coronary risk factors in patients with suspected coronary artery disease

International Nuclear Information System (INIS)

Tsukamoto, Takahiro; Naya, Masanao; Tsutsui, Hiroyuki; Morita, Koichi; Katoh, Chietsugu; Inubushi, Masayuki; Kuge, Yuji; Tamaki, Nagara

2006-01-01

Myocardial flow reserve (MFR) measurement has an important role in assessing the functional severity of coronary artery stenosis. However, a discrepancy between the anatomical severity of coronary artery stenosis and MFR is often observed. Such a discrepancy may be explained by coronary risk factors. In this study, we aimed to investigate the influence of coronary artery stenosis severity and risk factors on MFR. Seventy-four patients suspected to have coronary artery disease and seven age-matched healthy volunteers were enrolled. Myocardial blood flow (MBF) and MFR were measured using 15 O-labelled water PET. Regional MFR was calculated in regions with significant coronary artery stenosis (stenotic regions) and in regions without significant stenosis (remote regions). The contributions of coronary artery stenosis severity and coronary risk factors were assessed using univariate and multivariate analyses. In stenotic regions, MFR correlated inversely with coronary artery stenosis severity (r=-0.50, p<0.01). Univariate analysis did not show any significant difference in MFR between the patients with and the patients without each risk factor. In remote regions, however, MFR was significantly decreased in the diabetes and smoking groups (each p<0.05). By multivariate analysis, diabetes and smoking were independent predictors of MFR (each p<0.05). In the group with more than one risk factor, MFR was significantly lower (2.78±0.79) than in the other group (3.40±1.22, p<0.05). MFR is influenced not only by coronary stenosis severity but also by coronary risk factors. In particular, the influence of risk factors should be considered in regions without severe coronary stenosis. (orig.)

Non invasive cardiac vein mapping: Role of multislice CT coronary angiography

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Malago, Roberto, E-mail: robertomalag@yahoo.it [Radiology Department, University Hospital Policlinico G.B.Rossi, P.le L.A. Scuro 10, 37134 Verona (Italy); Pezzato, Andrea; Barbiani, Camilla; Sala, Giuseppe; Zamboni, Giulia A. [Radiology Department, University Hospital Policlinico G.B.Rossi, P.le L.A. Scuro 10, 37134 Verona (Italy); Tavella, Domenico [Cardiology Service, University Hospital Policlinico G.B.Rossi, P.le L.A. Scuro 10, 37134 Verona (Italy); Mucelli, Roberto Pozzi [Radiology Department, University Hospital Policlinico G.B.Rossi, P.le L.A. Scuro 10, 37134 Verona (Italy)

2012-11-15

Purpose: Coronary venous anatomy is of primary importance when implanting a cardiac resynchronization therapy device, besides, the coronary sinus can be differently enlarged depending on chronic heart failure. The aim of this study is to evaluate the usefulness of Coronary CTA in describing the coronary venous tree and in particular the coronary sinus and detecting main venous system variants. Materials and methods: 301 consecutive patients (196 Male-Sign , mean age 63.74 years) studied for coronary artery disease with 64 slice Coronary CTA were retrospectively examined. The acquisition protocol was the standard acquisition one used for coronary artery evaluation but the cardiac venous system were visualized. The cardiac venous system was depicted using 3D, MPR, cMPR and MIP post-processing reconstructions on an off-line workstation. For each patient image quality, presence and caliber of the coronary sinus (CS), great cardiac vein (GCV), middle vein (MV), anterior interventricular vein (AIV), lateral cardiac vein (LCV), posterior cardiac vein (PCV), small cardiac vein (SCV) and presence of variant of the normal anatomy were examined and recorded. Results: CS, GCV, MV and AIV were visualized in 100% of the cases. The LCV was visualized in 255/301 (84%) patients, the PCV in 248/301 (83%) patients and the SCV in 69/301 (23%) patients. Mean diameter of the CS was 8.7 mm in 276/301 (91.7%) patients without chronic heart failure and 9.93 mm in 25/301 (8.3%) patients with chronic heart failure. Conclusions: Coronary CTA allows non invasive mapping of the cardiac venous system and may represent a useful presurgical tool for biventricular pacemaker devices implantation.

Coronary artery aneurysms

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Koischwitz, D.; Harder, T.; Schuppan, U.; Thurn, P.

1982-04-01

Seven saccular coronary artery aneurysms have been demonstrated in the course of 1452 selective coronary artery angiograms. In six patients they were arterio-sclerotic; in one patient the aneurysm must have been congenital or of mycotic-embolic origin. The differential diagnosis between true aneurysms and other causes of vascular dilatation is discussed. Coronary artery aneurysms have a poor prognosis because of the possibility of rupture with resultant cardiac tamponade, or the development of thrombo-embolic myocardial infarction. These aneurysms can only be diagnosed by means of coronary angiography and require appropriate treatment.

Thallium scintigraphy during dobutamine infusion: nonexercise-dependent screening test for coronary disease

International Nuclear Information System (INIS)

Mason, J.R.; Palac, R.T.; Freeman, M.L.; Virupannavar, S.; Loeb, H.S.; Kaplan, E.; Gunnar, R.M.

1984-01-01

Exercise thallium scintigraphy has proven to be a sensitive method for detecting coronary artery disease (CAD). However, early redistribution of thallium and inadequate exercise can reduce its sensitivity. In this study, dobutamine was infused in incremental doses (5, 10, 15, and 20 micrograms/kg/min) in 24 patients being evaluated for chest pain. Thallium scintigraphy was completed during the maximum dose of dobutamine tolerated and repeated 4 hours later. Significant CAD was present in 16 patients; the remaining eight had normal coronaries. Exercise ECG was obtained in 23 patients. During dobutamine thallium scintigraphy, reversible perfusion defects occurred in 15 of 16 CAD and in one of eight non-CAD patients, resulting in a sensitivity of 94% and a specificity of 87%. Exercise ECG had a sensitivity of 60% and a specificity of 63%. We conclude that: (1) dobutamine thallium scintigraphy appears to be a sensitive method for detecting significant CAD and provided a more sensitive screening test than exercise ECG; (2) dobutamine thallium scintigraphy is especially useful in patients who cannot exercise; and (3) because imaging occurs during dobutamine infusion, the problem of early redistribution may be mitigated

Estimation of the flow resistances exerted in coronary arteries using a vessel length-based method.

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Lee, Kyung Eun; Kwon, Soon-Sung; Ji, Yoon Cheol; Shin, Eun-Seok; Choi, Jin-Ho; Kim, Sung Joon; Shim, Eun Bo

2016-08-01

Flow resistances exerted in the coronary arteries are the key parameters for the image-based computer simulation of coronary hemodynamics. The resistances depend on the anatomical characteristics of the coronary system. A simple and reliable estimation of the resistances is a compulsory procedure to compute the fractional flow reserve (FFR) of stenosed coronary arteries, an important clinical index of coronary artery disease. The cardiac muscle volume reconstructed from computed tomography (CT) images has been used to assess the resistance of the feeding coronary artery (muscle volume-based method). In this study, we estimate the flow resistances exerted in coronary arteries by using a novel method. Based on a physiological observation that longer coronary arteries have more daughter branches feeding a larger mass of cardiac muscle, the method measures the vessel lengths from coronary angiogram or CT images (vessel length-based method) and predicts the coronary flow resistances. The underlying equations are derived from the physiological relation among flow rate, resistance, and vessel length. To validate the present estimation method, we calculate the coronary flow division over coronary major arteries for 50 patients using the vessel length-based method as well as the muscle volume-based one. These results are compared with the direct measurements in a clinical study. Further proving the usefulness of the present method, we compute the coronary FFR from the images of optical coherence tomography.

Severity of coronary artery disease in obese patients undergoing coronary angiography

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Javed, A.; Ali, J.; Kayani, A.M.

2012-01-01

Objective: To assess the relationship of severity of coronary artery disease with obesity in patients undergoing coronary angiography. Design: Cross sectional study. Place and Duration of Study: Armed Forces Institute of Cardiology - National Institute of Heart Diseases (AFIC-NIHD), 1st February 2010 to 31st August 2010 Patients and Methods: The study population included 468 patients undergoing coronary angiography. Obesity was classified according to the BMI using the National Institutes of Health (NIH) criteria as normal (BMI 21-24 kg/m2), overweight (BMI 25-29 kg/m2), obesity class I (BMI 30-34 kg/m2), obesity class II (BMI 35 to 39 kg/m2 and obesity class III (BMI 40 or above kg/m2). Coronary angiography data were obtained from the Siemens Queries software system, which maintains the database including detailed angiographic findings of all patients at this institution. Significant lesions were defined as those with >70% diameter narrowing of coronary arteries (>50% for the left main coronary artery). We attempted to quantify the 'severity of CAD' by ascertaining the prevalence of High-Risk Coronary Anatomy (HRCA). Results: Insignificant difference was observed in traditional risk factors i.e. age, diabetes mellitus and smoking except hypertension and gender. Statistically significantly low prevalence of HRCA was encountered in the obese group (57.7%) as compared to normal/overweight group (75.8%) (p < 0.05). Conclusion: We conclude that obesity is associated with less severe coronary artery disease. (author)

Arterial response to shear stress critically depends on endothelial TRPV4 expression.

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Veronika Hartmannsgruber

Full Text Available BACKGROUND: In blood vessels, the endothelium is a crucial signal transduction interface in control of vascular tone and blood pressure to ensure energy and oxygen supply according to the organs' needs. In response to vasoactive factors and to shear stress elicited by blood flow, the endothelium secretes vasodilating or vasocontracting autacoids, which adjust the contractile state of the smooth muscle. In endothelial sensing of shear stress, the osmo- and mechanosensitive Ca(2+-permeable TRPV4 channel has been proposed to be candidate mechanosensor. Using TRPV4(-/- mice, we now investigated whether the absence of endothelial TRPV4 alters shear-stress-induced arterial vasodilation. METHODOLOGY/PRINCIPAL FINDINGS: In TRPV4(-/- mice, loss of the TRPV4 protein was confirmed by Western blot, immunohistochemistry and by in situ-patch-clamp techniques in carotid artery endothelial cells (CAEC. Endothelium-dependent vasodilation was determined by pressure myography in carotid arteries (CA from TRPV4(-/- mice and wild-type littermates (WT. In WT CAEC, TRPV4 currents could be elicited by TRPV4 activators 4alpha-phorbol-12,13-didecanoate (4alphaPDD, arachidonic acid (AA, and by hypotonic cell swelling (HTS. In striking contrast, in TRPV4(-/- mice, 4alphaPDD did not produce currents and currents elicited by AA and HTS were significantly reduced. 4alphaPDD caused a robust and endothelium-dependent vasodilation in WT mice, again conspicuously absent in TRPV4(-/- mice. Shear stress-induced vasodilation could readily be evoked in WT, but was completely eliminated in TRPV4(-/- mice. In addition, flow/reperfusion-induced vasodilation was significantly reduced in TRPV4(-/- vs. WT mice. Vasodilation in response to acetylcholine, vasoconstriction in response to phenylephrine, and passive mechanical compliance did not differ between genotypes, greatly underscoring the specificity of the above trpv4-dependent phenotype for physiologically relevant shear stress

Arterial Response to Shear Stress Critically Depends on Endothelial TRPV4 Expression

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Kacik, Michael; Kaistha, Anuradha; Grgic, Ivica; Harteneck, Christian; Liedtke, Wolfgang; Hoyer, Joachim; Köhler, Ralf

2007-01-01

Background In blood vessels, the endothelium is a crucial signal transduction interface in control of vascular tone and blood pressure to ensure energy and oxygen supply according to the organs' needs. In response to vasoactive factors and to shear stress elicited by blood flow, the endothelium secretes vasodilating or vasocontracting autacoids, which adjust the contractile state of the smooth muscle. In endothelial sensing of shear stress, the osmo- and mechanosensitive Ca2+-permeable TRPV4 channel has been proposed to be candidate mechanosensor. Using TRPV4−/− mice, we now investigated whether the absence of endothelial TRPV4 alters shear-stress-induced arterial vasodilation. Methodology/Principal Findings In TRPV4−/− mice, loss of the TRPV4 protein was confirmed by Western blot, immunohistochemistry and by in situ-patch–clamp techniques in carotid artery endothelial cells (CAEC). Endothelium-dependent vasodilation was determined by pressure myography in carotid arteries (CA) from TRPV4−/− mice and wild-type littermates (WT). In WT CAEC, TRPV4 currents could be elicited by TRPV4 activators 4α-phorbol-12,13-didecanoate (4αPDD), arachidonic acid (AA), and by hypotonic cell swelling (HTS). In striking contrast, in TRPV4−/− mice, 4αPDD did not produce currents and currents elicited by AA and HTS were significantly reduced. 4αPDD caused a robust and endothelium-dependent vasodilation in WT mice, again conspicuously absent in TRPV4−/− mice. Shear stress-induced vasodilation could readily be evoked in WT, but was completely eliminated in TRPV4−/− mice. In addition, flow/reperfusion-induced vasodilation was significantly reduced in TRPV4−/− vs. WT mice. Vasodilation in response to acetylcholine, vasoconstriction in response to phenylephrine, and passive mechanical compliance did not differ between genotypes, greatly underscoring the specificity of the above trpv4-dependent phenotype for physiologically relevant shear stress. Conclusions

Coronary Anomaly and Coronary Artery Fistula as Cause of Angina Pectoris with Literature Review

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Jayanth Koneru

2011-01-01

Full Text Available Coronary artery fistulas are rare anomalies of the coronary arteries that may sometimes cause symptoms by shunting blood flow away from the myocardial capillary network. We report the case of a 46-year old lady which shows the right coronary cusp giving rise to left main coronary artery called anomalous origin of a coronary artery (AOCA, and also a fistula between the left coronary artery and pulmonary artery. We describe our diagnostic approach and review the literature on the epidemiology, pathophysiology, the diagnostic modalities, and treatment options.

Role of coronary physiology in the contemporary management of coronary artery disease

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Ruparelia, Neil; Kharbanda, Rajesh K

2015-01-01

Coronary artery disease (CAD) remains the leading cause of death worldwide with approximately 1 in 30 patients with stable CAD experiencing death or acute myocardial infarction each year. The presence and extent of resultant myocardial ischaemia has been shown to confer an increased risk of adverse outcomes. Whilst, optimal medical therapy (OMT) forms the cornerstone of the management of patients with stable CAD, a significant number of patients present with ischaemia refractory to OMT. Historically coronary angiography alone has been used to determine coronary lesion severity in both stable and acute settings. It is increasingly clear that this approach fails to accurately identify the haemodynamic significance of lesions; especially those that are visually “intermediate” in severity. Revascularisation based upon angiographic appearances alone may not reduce coronary events above OMT. Technological advances have enabled the measurement of physiological indices including the fractional flow reserve, the index of microcirculatory resistance and the coronary flow reserve. The integration of these parameters into the routine management of patients presenting to the cardiac catheterization laboratory with CAD represents a critical adjunctive tool in the optimal management of these patients by identifying patients that would most benefit from revascularisation and importantly also highlighting patients that would not gain benefit and therefore reducing the likelihood of adverse outcomes associated with coronary revascularisation. Furthermore, these techniques are applicable to a broad range of patients including those with left main stem disease, proximal coronary disease, diabetes mellitus, previous percutaneous coronary intervention and with previous coronary artery bypass grafting. This review will discuss current concepts relevant to coronary physiology assessment, its role in the management of both stable and acute patients and future applications. PMID

Role of coronary physiology in the contemporary management of coronary artery disease.

Science.gov (United States)

Ruparelia, Neil; Kharbanda, Rajesh K

2015-02-16

Coronary artery disease (CAD) remains the leading cause of death worldwide with approximately 1 in 30 patients with stable CAD experiencing death or acute myocardial infarction each year. The presence and extent of resultant myocardial ischaemia has been shown to confer an increased risk of adverse outcomes. Whilst, optimal medical therapy (OMT) forms the cornerstone of the management of patients with stable CAD, a significant number of patients present with ischaemia refractory to OMT. Historically coronary angiography alone has been used to determine coronary lesion severity in both stable and acute settings. It is increasingly clear that this approach fails to accurately identify the haemodynamic significance of lesions; especially those that are visually "intermediate" in severity. Revascularisation based upon angiographic appearances alone may not reduce coronary events above OMT. Technological advances have enabled the measurement of physiological indices including the fractional flow reserve, the index of microcirculatory resistance and the coronary flow reserve. The integration of these parameters into the routine management of patients presenting to the cardiac catheterization laboratory with CAD represents a critical adjunctive tool in the optimal management of these patients by identifying patients that would most benefit from revascularisation and importantly also highlighting patients that would not gain benefit and therefore reducing the likelihood of adverse outcomes associated with coronary revascularisation. Furthermore, these techniques are applicable to a broad range of patients including those with left main stem disease, proximal coronary disease, diabetes mellitus, previous percutaneous coronary intervention and with previous coronary artery bypass grafting. This review will discuss current concepts relevant to coronary physiology assessment, its role in the management of both stable and acute patients and future applications.

Acute Thrombotic Coronary Occlusion in a Patient with Coronary Artery Anomaly

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Beganu Elena

2017-09-01

Full Text Available Patients with coronary artery anomalies are more susceptible to develop acute thrombotic coronary occlusions due to the abnormal anatomy of these arteries and the disturbance of the pathophysiological mechanisms that lead to an accelerated atherosclerosis development. The following article presents the case of a 64-year-old female patient diagnosed with anterior ST-segment elevation myocardial infarction. The patient underwent primary percutaneous coronary intervention, which revealed the absence of the right coronary artery and separated origins of the left anterior descending artery and the left circumflex artery from the aorta.

Factors influencing delay time and coronary arterial density during coronary angiography with DSCT

International Nuclear Information System (INIS)

Lijun Tang; Xiaomei Zhu; Yi Xu; Tongfu Yu; Hai Xu; Jinhua Tang; Dehang Wang; Dogra, Vikram

2011-01-01

Background: CT angiography (CTA) plays an important role in diagnosing coronary arterial disease. Delay time and density of the coronary arteries related with patient-specific factors are essential for getting an optimal CTA image. Purpose: To investigate various factors influencing delay time and coronary arterial density during coronary CTA with dual source CT. Material and Methods: One hundred and sixteen consecutive subjects who underwent cardiac DSCT with retrospective ECG-gating were included. Factors including gender, age, height, weight, transversal cardiac diameter (TCD), transversal thoracic diameter (TTD), heart rate (HR), body surface area (BSA = [weight x height/3600]1/2) and cardiothoracic ratio (CTR = TCD/TTD) were recorded, measured and calculated before administration of contrast media during coronary CT angiography. Delay time was determined as duration from the beginning of the injection to the density in the descending aorta at the level of right main pulmonary artery reaching a threshold of 100 HU. Coronary arterial density was measured at the mid portion of the right coronary artery. Regression analysis and stepwise regression analysis were used to investigate the influence of these factors on delay time and coronary arterial density. Results: Delay time decreased with an increasing HR and it was shorter in women than men. Delay time increased with an increasing TCD. Delay time could be predicted by the formula: DT = 16.651-0.110 x HR + 1.902 x gender + 0.394 x TCD (where DT is abbreviation for delay time, gender is 0 for women and 1 for men). Coronary arterial density decreased with an increasing HR and weight. Coronary arterial density could be predicted by the formula: CAD = 923.42-4.099 x HR-3.293 x weight (CAD = coronary arterial density). There was no relationship between the other factors mentioned above and delay time or coronary arterial density. Conclusion: Delay time is influenced by HR, gender and TCD. Coronary arterial density

Multiple Culprit Coronary Artery Thrombosis in a Patient with Coronary Ectasia

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Bruno da Silva Matte

2018-01-01

Full Text Available We here report a case of ST-elevation myocardial infarction (STEMI due to simultaneous acute coronary artery occlusions of two major coronary arteries in a patient with coronary ectasia. The patient had been previously submitted to percutaneous coronary angioplasty with bare metal stent implantation in both culprit vessels. Very late stent thrombosis could be the cause of the first occlusion, triggering the event in the other vessel. In addition, concomitant embolic sources were not identified. Although routine aspiration thrombectomy in STEMI was not proven to be beneficial in randomized clinical trials, it was of great value in this case. We also discuss the relation between coronary ectasia, chronic inflammatory status, and increased platelet activity which may have caused plaque disruption in another already vulnerable vessel.

[Experimental evaluation of the role of the coronary sinus pressure in the regulation of coronary return volume via the coronary sinus. Surgical considerations in atrio-pulmonary diversion procedures].

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Fantidis, P; Fernández Ruiz, M A; Madero Jarabo, R; Moreno Granados, F; Cordovilla Zurdo, G; Sanz Galeote, E

1990-11-01

In order to find out the validity of the vascular waterfall mechanism in coronary venous circulation, the role of coronary sinus pressure in the regulation of coronary return volume via the coronary sinus is studied in healthy animals. An experimental model of pressure regulation in the coronary sinus was prepared, and aortic pressure, EKG and the cardiac output (measured by thermodilution) were recorded. The return volume via the coronary sinus was measured at coronary sinus pressure of 10 or less, 15, 20, and 25 mmHg or more, for a total of 36 determinations. Increased coronary sinus pressure did not produce significant changes in aortic pressure, heart rate, cardiac index or coronary return volume via coronary sinus. When coronary sinus pressure was 25 mmHg or more, there was a significant decline in the average of coronary return volume via coronary sinus. Nevertheless, stepwise variant regression showed that the coronary sinus pressure per se does not condition the volume of coronary return via the coronary sinus. Our results suggest that in the healthy animals, the vascular waterfall mechanism in coronary venous circulation is not valid. Our results suggest that in the correction of congenital cardiac malformations using atriopulmonary anastomosis procedures, employing techniques that ensure coronary sinus drainage into the left atrium, in order to avoid the hemodynamic repercussions attributable to the vascular waterfall mechanism, is not justified.

Mechanisms underlying epithelium-dependent relaxation in rat bronchioles

DEFF Research Database (Denmark)

Kroigaard, Christel; Dalsgaard, Thomas; Simonsen, Ulf

2010-01-01

This study investigated the mechanisms underlying epithelium-derived hyperpolarizing factor (EpDHF)-type relaxation in rat bronchioles. Immunohistochemistry was performed, and rat bronchioles and pulmonary arteries were mounted in microvascular myographs for functional studies. An opener of small...... (SK(Ca)) and intermediate (IK(Ca))-conductance calcium-activated potassium channels, NS309 (6,7-dichloro-1H-indole-2,3-dione 3-oxime) was used to induce EpDHF-type relaxation. IK(Ca) and SK(Ca)3 positive immunoreactions were observed mainly in the epithelium and endothelium of bronchioles and arteries......, respectively. In 5-hydroxytryptamine (1 microM)-contracted bronchioles (828 +/- 20 microm, n = 84) and U46619 (0.03 microM)-contracted arteries (720 +/- 24 microm, n = 68), NS309 (0.001-10 microM) induced concentration-dependent relaxations that were reduced by epithelium/endothelium removal and by blocking IK...

Relationship between vascular endothelium and periodontal disease in atherosclerotic lesions: Review article

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Saffi, Marco Aurélio Lumertz; Furtado, Mariana Vargas; Polanczyk, Carisi Anne; Montenegro, Márlon Munhoz; Ribeiro, Ingrid Webb Josephson; Kampits, Cassio; Haas, Alex Nogueira; Rösing, Cassiano Kuchenbecker; Rabelo-Silva, Eneida Rejane

2015-01-01

Inflammation and endothelial dysfunction are linked to the pathogenesis of atherosclerotic disease. Recent studies suggest that periodontal infection and the ensuing increase in the levels of inflammatory markers may be associated with myocardial infarction, peripheral vascular disease and cerebrovascular disease. The present article aimed at reviewing contemporary data on the pathophysiology of vascular endothelium and its association with periodontitis in the scenario of cardiovascular disease. PMID:25632316

Distinct mechanisms of relaxation to bioactive components from chamomile species in porcine isolated blood vessels

International Nuclear Information System (INIS)

Roberts, R.E.; Allen, S.; Chang, A.P.Y.; Henderson, H.; Hobson, G.C.; Karania, B.; Morgan, K.N.; Pek, A.S.Y.; Raghvani, K.; Shee, C.Y.; Shikotra, J.; Street, E.; Abbas, Z.; Ellis, K.; Heer, J.K.; Alexander, S.P.H.

2013-01-01

German chamomile (Matricaria recutita L.), a widely-used herbal medicine, has been reported to have a wide range of biological effects, including smooth muscle relaxation. The aim of this study was to compare the effects of representative compounds from chamomile (apigenin, luteolin, (−)-α-bisabolol, farnesene, umbelliferone; 3–30 μM) on vascular tone using porcine coronary and splenic arteries mounted for isometric tension recording in isolated tissue baths and precontracted with the thromboxane-mimetic U46619. Apigenin, luteolin, and (−)-α-bisabolol produced slow, concentration-dependent relaxations in both the coronary and splenic arteries that were not blocked by inhibition of nitric oxide synthase or potassium channels. Removal of extracellular calcium inhibited the relaxations to all three compounds, and these compounds also inhibited calcium re-addition-evoked contractions, indicating that the relaxation response may be mediated through inhibition of calcium influx. Apigenin and luteolin, but not (−)-α-bisabolol, enhanced the relaxation to the nitric oxide donor sodium nitroprusside, indicating that apigenin and luteolin may act to regulate cyclic GMP levels. Umbelliferone produced a rapid, transient relaxation in the splenic artery, but not the coronary artery, that was inhibited by L-NAME and removal of the endothelium, suggesting an influence on nitric oxide production. Farnesene, at concentrations up to 30 μM, was without effect in either blood vessel. In conclusion, hydroxylated compounds (apigenin, luteolin and (−)-α-bisabolol) found in chamomile all caused a slow relaxation of isolated blood vessels through an effect on calcium influx. Umbelliferone, on the other hand, produced a rapid, transient relaxation dependent upon release of nitric oxide from the endothelium. - Highlights: • Apigenin, luteolin, and (-)-α-bisabolol are present in chamomile. • They produced slow, concentration-dependent relaxations in arteries. • These

Distinct mechanisms of relaxation to bioactive components from chamomile species in porcine isolated blood vessels

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Roberts, R.E., E-mail: Richard.roberts@nottingham.ac.uk; Allen, S.; Chang, A.P.Y.; Henderson, H.; Hobson, G.C.; Karania, B.; Morgan, K.N.; Pek, A.S.Y.; Raghvani, K.; Shee, C.Y.; Shikotra, J.; Street, E.; Abbas, Z.; Ellis, K.; Heer, J.K.; Alexander, S.P.H., E-mail: steve.alexander@nottingham.ac.uk

2013-11-01

German chamomile (Matricaria recutita L.), a widely-used herbal medicine, has been reported to have a wide range of biological effects, including smooth muscle relaxation. The aim of this study was to compare the effects of representative compounds from chamomile (apigenin, luteolin, (−)-α-bisabolol, farnesene, umbelliferone; 3–30 μM) on vascular tone using porcine coronary and splenic arteries mounted for isometric tension recording in isolated tissue baths and precontracted with the thromboxane-mimetic U46619. Apigenin, luteolin, and (−)-α-bisabolol produced slow, concentration-dependent relaxations in both the coronary and splenic arteries that were not blocked by inhibition of nitric oxide synthase or potassium channels. Removal of extracellular calcium inhibited the relaxations to all three compounds, and these compounds also inhibited calcium re-addition-evoked contractions, indicating that the relaxation response may be mediated through inhibition of calcium influx. Apigenin and luteolin, but not (−)-α-bisabolol, enhanced the relaxation to the nitric oxide donor sodium nitroprusside, indicating that apigenin and luteolin may act to regulate cyclic GMP levels. Umbelliferone produced a rapid, transient relaxation in the splenic artery, but not the coronary artery, that was inhibited by L-NAME and removal of the endothelium, suggesting an influence on nitric oxide production. Farnesene, at concentrations up to 30 μM, was without effect in either blood vessel. In conclusion, hydroxylated compounds (apigenin, luteolin and (−)-α-bisabolol) found in chamomile all caused a slow relaxation of isolated blood vessels through an effect on calcium influx. Umbelliferone, on the other hand, produced a rapid, transient relaxation dependent upon release of nitric oxide from the endothelium. - Highlights: • Apigenin, luteolin, and (-)-α-bisabolol are present in chamomile. • They produced slow, concentration-dependent relaxations in arteries. • These

Three-Dimensional Respiratory-Gated Coronary Mr Angiography with Reference to X-Ray Coronary Angiography

International Nuclear Information System (INIS)

Ikonen, A. E. J.; Manninen, H. I.; Vainio, P.; Vanninen, R. L.; Matsi, P. J.; Soimakallio, S.; Hirvonen, T.P.J.; Hartikainen, J.E.K.

2003-01-01

Purpose: To assess the clinical value of three-dimensional coronary MR angiography (CMRA) in the detection of significant coronary artery stenosis using conventional X-ray angiography as the standard reference. Material and Methods: Sixty-nine patients underwent X-ray coronary angiography and CMRA because of suspected or previously diagnosed coronary artery disease. MRI was performed with a 1.5-T whole body imaging system using ECG-triggered 3D gradient echo sequence with retrospective navigator echo respiratory gating and fat suppression. Results: A total of 276 coronary artery segments were analyzed. The X-ray coronary angiography was normal in 22 patients. Significant proximal stenoses (exceeding 50%) or occlusions were present in 102 coronary artery segments. In all, 120 stenoses or occlusions were identified in CMRA. Sixteen percent of the coronary artery segments had to be excluded because of poor image quality. The overall sensitivity and specificity for MRA for identification of significant stenosis were 75% and 62%, respectively. CMRA correctly detected 89% of patients with at least one vessel disease, but 6 patients with coronary artery disease would have been missed. Conclusions: Because of the high data exclusion and false-negative case rate, CMRA with retrospective navigator echo triggering is at present not suitable as a clinical screening method in coronary artery disease

Coronary artery anomalies in adults: imaging at dual source CT coronary angiography

International Nuclear Information System (INIS)

Laspas, Fotios; Roussakis, Arkadios; Mourmouris, Christos; Kritikos, Nikolaos; Efthimiadou, Roxani; Andreou, John

2013-01-01

Congenital abnormalities of the coronary arteries have an incidence of 1%, and most of these are benign. However, a small number are associated with myocardial ischaemia and sudden death. Various imaging modalities are available for coronary artery assessment. Recently, multi-detector CT has emerged as an accurate diagnostic tool for defining coronary artery anomalies. The purpose of this pictorial essay is to review the dual source CT appearance of congenital anomalies of the coronary arteries in adults.

Vascular endothelium as a target of immune response in renal transplant rejection

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Giovanni ePiotti

2014-10-01

Full Text Available This review of clinical and experimental studies aims at analysing the interplay between graft endothelium and host immune system in renal transplantation, and how it affects the survival of the graft. Graft endothelium is indeed the first barrier between self and non-self that is encountered by host lymphocytes upon reperfusion of vascularised solid transplants. Endothelial cells express all the major sets of antigens that elicit host immune response, and therefore represent a preferential target in organ rejection.Some of the antigens expressed by endothelial cells are target of the antibody-mediated response, such as the AB0 blood group system, the HLA and MICA systems, and the endothelial cell-restricted antigens; for each of these systems, the mechanisms of interaction and damage of both preformed and de novo donor-specific antibodies are reviewed along with their impact on renal graft survival. Moreover the rejection process can force injured endothelial cells to expose cryptic self-antigens, toward which an auto-immune response mounts, overlapping to the allo-immune response in the damaging of the graft. Not only are endothelial cells a passive target of the host immune response, but also an active player in lymphocyte activation; therefore their interaction with allogenic T-cells is analysed on the basis of experimental in vitro and in vivo studies, according to the patterns of expression of the HLA class I and II and the co-stimulatory molecules specific for cytotoxic and helper T-cells.Finally, as the response that follows transplantation has proven to be not necessarily destructive, the factors that foster graft endothelium functioning in spite of rejection, and how they could be therapeutically harnessed to promote long-term graft acceptance, are described: accommodation that is resistance of endothelial cells to donor-specific antibodies, and endothelial cell ability to induce Foxp3+ Regulatory T-cells, that are crucial mediators of

The value of coronary artery calcium score assessed by dual-source computed tomography coronary angiography for predicting presence and severity of coronary artery disease

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Almasi, Alireza; Pouraliakbar, Hamidreza; Sedghian, Ahmad; Karimi, Mohammad Ali; Firouzi, Ata; Tehrai, Mahmood

2014-01-01

Measuring coronary artery calcium score (CACS) using a dual-source CT scanner is recognized as a major indicator for assessing coronary artery disease. The present study aimed to validate the clinical significance of CACS in predicting coronary artery stenosis and its severity. This prospective study was conducted on 202 consecutive patients who underwent both conventional coronary angiography and dual-source (256-slice) computed tomography coronary angiography (CTA) for any reason in our cardiac imaging center from March to September 2013. CACS was measured by Agatston algorithm on non-enhanced CT. The severity of coronary artery disease was assessed by Gensini score on conventional angiography. There was a significant relationship between the number of diseased coronary vessels and mean calcium score, i.e. the mean calcium score was 202.25±450.06 in normal coronary status, 427.50±607.24 in single-vessel disease, 590.03±511.34 in two-vessel disease, and 953.35±1023.45 in three-vessel disease (p<0.001). There was a positive association between calcium score and Gensini score (r=0.636, p<0.001). In a linear regression model, calcium score was a strong determinant of the severity of coronary artery disease. Calcium scoring had an acceptable value for discriminating coronary disease from normal condition with optimal cutoff point of 350, yielding a sensitivity and specificity of 83% and 70%, respectively. Our study confirmed the strong relationship between the coronary artery calcium score and the presence and severity of stenosis in coronary arteries assessed by both the number of diseased coronary vessels and also by the Gnesini score

CORONARY ARTERY DOMINANCE PATTERN IN EAST-GODAVARI DISTRICT: A CADAVERIC STUDY

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Arindom

2016-01-01

Full Text Available With the advent of coronary angiography, coronary artery diseases can be well combated; but with time sedentary life style and stress as our constant partner have kept coronary artery disease as one of the major causes of death. Revascularization procedures demand a sound knowledge of the course of coronary arteries and their branches, both normal and their quite common variations. In this regard, posterior inter-ventricular artery (PIVA deserves a special importance; PIVA determines the coronary dominance depending on its parent artery. Dominance can be right, left or of balanced type. Balanced type means that PIVA is derived from both right & left coronary arteries. Circulation can occur when both the coronary arteries emit a branch in that area. These and other variations form a very important repertoire of information based on which coronary bypass surgery and angioplasty can be safely and effectively performed. The aim of this study therefore is to document the coronary dominance pattern in this East Godavari district of Andhra-Pradesh. 60 adult human hearts were collected from museum of Anatomy department during the tenure of 5 years (2009 to 2014 and were preserved in 10% formalin. The hearts were dissected carefully to observe the posterior inter-ventricular artery in the posterior inter-ventricular sulcus of each heart and dominance pattern was recorded. In our present study right dominance type was the commonest (46 out of 60 followed by left dominance (10 out of 60. Only 4 out of 60 were of the balanced type. Present study, though not of the only member of its kind will definitely add up to the already existing vast knowledge, based on which various diagnostic and therapeutic intervention of coronary artery diseases can be done effectively and safely

Visual outcomes after deep anterior lamellar keratoplasty using donor corneas without removal of Descemet membrane and endothelium

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Tatiana Moura Bastos Prazeres

Full Text Available ABSTRACT Purpose: The optical quality of the interface after deep anterior lamellar keratoplasty (DALK using the big-bubble technique has been shown to be excellent, leading to results comparable to penetrating keratoplasty. However, there is little in the literature with respect to the controversy surrounding the preparation of the donor cornea. The purpose of this study was to evaluate visual acuity (VA in patients with keratoconus who underwent DALK without removal of the donor graft endothelium. Methods: The records of 90 patients who underwent DALK without the removal of the Descemet membrane (DM and endothelium were retrospectively reviewed. Data collected included uncorrected VA (UCVA and spectacle-corrected VA (SCVA at 7, 30, 180 days, and 1 year postoperatively. Contact lens-corrected visual acuity (CLVA was evaluated after 1 year of the procedure. Results: UCVA was significantly better than preoperative values at 7 days (p<0.001, 30 days (p<0.001, 180 days (p<0.001, and 1 year (p<0.001 after surgery. The 1-year postoperative mean SCVA and CLVA also improved when compared with preoperative SCVA (p<0.001 for both. Conclusions: DALK utilizing donor corneas with attached Descemet membrane and endothelium results in satisfactory VA in patients with keratoconus.

Development of Coronary Pulse Wave Velocity: New Pathophysiological Insight Into Coronary Artery Disease.

Science.gov (United States)

Harbaoui, Brahim; Courand, Pierre-Yves; Cividjian, Andrei; Lantelme, Pierre

2017-02-02

Although aortic stiffness assessed by pulse wave velocity (PWV) is a strong predictor of coronary artery disease, the significance of local coronary stiffness has never been tackled. The first objective of this study was to describe a method of measuring coronary PWV (CoPWV) invasively and to describe its determinants. The second objective was to assess both CoPWV and aortic PWV in patients presenting with acute coronary syndromes or stable coronary artery disease. In 53 patients, CoPWV was measured from the delay in pressure wave and distance traveled as a pressure wire was withdrawn from the distal to the proximal coronary segment. Similarly, aortic PWV was measured invasively when the wire was pulled across the ascending aorta; carotid-femoral PWV was also measured noninvasively using the SphygmoCor system (AtCor Medical). Mean CoPWV was 10.3±6.1 m/s. Determinants of increased CoPWV were fractional flow reserve, diastolic blood pressure, and previous stent implantation in the recorded artery. CoPWV was lower in patients with acute coronary syndromes versus stable coronary artery disease (7.6±3 versus 11.5±6.4 m/s; P=0.02), and this persisted after adjustment for confounders. In contrast, aortic stiffness, assessed by aortic and carotid-femoral PWV, did not differ significantly. CoPWV seems associated with acute coronary events more closely than aortic PWV. High coronary compliance, whether per se or because it leads to a distal shift in compliance mismatch, may expose vulnerable plaques to high cyclic stretch. CoPWV is a new tool to assess local compliance at the coronary level; it paves the way for a new field of research. © 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

Coronary MR angiography: current status

International Nuclear Information System (INIS)

Danias, P.G.; Manning, W.J.

2000-01-01

Since first described in the early 1990s, coronary magnetic resonance angiography (MRA) has evolved as a promising noninvasive modality for imaging of the coronary arteries and evaluation of coronary artery disease. Despite technical limitations, coronary MRA has established value for imaging of anomalous coronary arteries and assessment of bypass graft patency. Current research focuses on the development of optimal respiratory compensation strategies, improved spatial and temporal resolution and faster acquisition of image data. The accurate detection of stenoses and assessment of the severity of coronary atherosclerosis is presently being evaluated with large multi-center studies. With further technique enhancements and more clinical experience, coronary MRA is likely to become the dominant noninvasive modality in clinical cardiology. (orig.) [de

Balloon Occlusion Types in the Treatment of Coronary Perforation during Percutaneous Coronary Intervention

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Xiangfei Wang

2014-01-01

Full Text Available Coronary artery perforation is an uncommon complication in patients with coronary heart disease undergoing percutaneous coronary intervention. However, pericardial tamponade following coronary artery perforation may be lethal, and prompt treatment is crucial in managing such patients. Balloon occlusion and the reversal of anticoagulant activity are the common methods used to prevent cardiac tamponade by reducing the amount of bleeding. Herein, we discuss the pros and cons of currently used occlusion types for coronary perforation. Optimal balloon occlusion methods should reduce the amount of bleeding and ameliorate subsequent myocardial ischemia injury, even during cardiac surgery.

Congenital coronary artery fistula

International Nuclear Information System (INIS)

Oh, Yeon Hee; Kim, Hong; Zeon, Seoc Kil; Suh, Soo Jhi

1986-01-01

Congenital coronary artery fistula (CCAF) is communication of a coronary artery or its main branch with one of the atria or ventricles, the coronary sinus, the superior vena cava, or the pulmonary artery. In Korean peoples, only 4 cases of the CCAF were reported as rare as worldwide and authors want to report another case of CCAF, confirmed by operation. 10-year-old girl shows a fistula between sinus node artery of the right coronary artery and right atrium on root aortogram with left-to-right shunt and Qp/Qs=1.58, in which simple ligation of the sinus node artery from right coronary artery was performed. All of the 5 Korean CCAF (4 were previously reported and 1 of authors) were originated from right coronary artery, and of which 4 were opening into right ventricle and 1 of authors were into right atrium. Associated cardiac anomaly was noted in only 1 case as single coronary artery. Ages were from 9 months of age to 10 years old and no adult left case were found. 3 were female and 2 were male patients.

Non-invasive assessment of coronary calcification

International Nuclear Information System (INIS)

Vliegenthart, Rozemarijn; Oei, Hok-Hay S.; Hofman, Albert; Oudkerk, Matthijs; Witteman, Jackqueline C. M.

2004-01-01

Electron-beam tomography (EBT) and multi-detector computed tomography (MDCT) enable the noninvasive assessment of coronary calcification. The amount of coronary calcification, as detected by EBT, has a close relation with the amount of coronary atherosclerosis, which is the substrate for the occurrence of myocardial infarction and sudden cardiac death. Calcification of the coronary arteries can be seen as a cumulative measure of life-time exposure to cardiovascular risk factors. Several studies have shown that the amount of coronary calcification is associated with the risk of coronary heart disease. Therefore, coronary calcification is a promising method for non-invasive detection of asymptomatic subjects at high risk of developing coronary heart disease. Whether measurement of coronary calcification also increases the predictive power of coronary events based on cardiovascular risk factors is topic of current research

[Pregnancy and coronary artery dissection].

Science.gov (United States)

Martínez-Quintana, Efrén; Rodríguez-González, Fayna

2015-01-01

Acute myocardial infarction during pregnancy is associated with high maternal and fetal mortality. Coronary atherosclerosis is the most common cause due to an increase in the age of the patients and the association with cardiovascular risk factors such as smoking, hypertension, diabetes mellitus, preeclampsia, and the existence of family history of coronary disease. However, thrombosis, coronary dissection or coronary vasospasms are other causes that may justify it. We report the case of a 33 weeks pregnant first-time mother, without cardiovascular risk factors, who presented an acute coronary event in the context of atherosclerotic disease and coronary dissection after percutaneous coronary intervention. Copyright © 2014 Sociedad Española de Arteriosclerosis. Published by Elsevier España. All rights reserved.

Effects of exercise training on coronary collateralization and control of collateral resistance

Science.gov (United States)

Parker, Janet L.

2011-01-01

Coronary collateral vessels serve as a natural protective mechanism to provide coronary flow to ischemic myocardium secondary to critical coronary artery stenosis. The innate collateral circulation of the normal human heart is typically minimal and considerable variability occurs in extent of collateralization in coronary artery disease patients. A well-developed collateral circulation has been documented to exert protective effects upon myocardial perfusion, contractile function, infarct size, and electrocardiographic abnormalities. Thus therapeutic augmentation of collateral vessel development and/or functional adaptations in collateral and collateral-dependent arteries to reduce resistance into the ischemic myocardium represent a desirable goal in the management of coronary artery disease. Tremendous evidence has provided documentation for the therapeutic benefits of exercise training programs in patients with coronary artery disease (and collateralization); mechanisms that underlie these benefits are numerous and multifaceted, and currently under investigation in multiple laboratories worldwide. The role of enhanced collateralization as a major beneficial contributor has not been fully resolved. This topical review highlights literature that examines the effects of exercise training on collateralization in the diseased heart, as well as effects of exercise training on vascular endothelial and smooth muscle control of regional coronary tone in the collateralized heart. Future directions for research in this area involve further delineation of cellular/molecular mechanisms involved in effects of exercise training on collateralized myocardium, as well as development of novel therapies based on emerging concepts regarding exercise training and coronary artery disease. PMID:21565987

Multi-slice spiral CT coronary angiography: influence of heart rate and reconstruction window on image quality

International Nuclear Information System (INIS)

Mao Dingbiao; Hua Yanqing; Wang Mingpeng; Zhang Guozhen; Wu Weilan; Hu Fei; Ge Xiaojun; Ding Qiyong

2004-01-01

Objective: To evaluate the influence of heart rate and reconstruction window on image quality of multi-slice spiral CT coronary angiography. Methods: Retrospectively ECG-gated MSCT coronary angiography were performed in 80 healthy cases. Results: Four coronary (RCA, LM, LAD, LCX) segments were analyzed in each patient with regard to image quality. 82.1% (46/56) of the coronary segments were sufficient for analysis in patients with heart rate ≤60 bpm, 63.4% (104/164) with 61-70 bpm, 41.2%(28/68) with 71-80 bpm, and 31.2%(10/32) with>80 bpm, respectively. The left anterior descending artery, left circumflex artery, and the right coronary artery were best visualized when the reconstruction window was 60%-70%, 50%-60%, and 50%-70%, respectively. Conclusion: Image quality of MSCT coronary angiography is highly dependent on heart rate and reconstruction window

Single coronary artery; extremely rare coronary anomaly successfully treated surgically in young adult male.

LENUS (Irish Health Repository)

Shah, A R

2010-05-01

Single coronary artery arising from aortic root, is a rare congenital anomaly. A 30-year-old male presented with acute myocardial infarction (MI) complaining of chest pain and raised troponin levels. Emergency angiography showed no coronary lesions but both left and right coronary arteries arising from single ostium. Patient was operated electively and perioperative findings confirmed the diagnosis of single coronary artery, as left coronary artery after taking origin from right sinus of valsalva runs through the septum, before dividing into left anterior descending and circumflex branches. The single coronary ostium opened with a slit like incision over the course of left main coronary, making the size of ostium three to four times bigger than the native one. In addition left internal mammary artery was harvested and grafted to the left anterior descending branch distally. Patient made successful recovery. Four months follow up dobutamine stress echo showed no inducible ischemia.

PLACENTAL GROWTH FACTOR AND CORONARY NEOANGIOGENESIS IN CORONARY HEART DISEASE

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M. V. Tulikov

2013-01-01

Full Text Available Neoangiogenesis in coronary heart disease is a protective reaction aimed to improve ischemic myocardial perfusion, by increasing the number and size of arterial collaterals. Placental growth factor (PlGF is one of the key peptides regulating angiogenic processes in atherosclerosis. In particular, a number of investigators have shown that injection of recombinant PlGF into the system or regional blood flow can stimulate neoangiogenesis. On the other hand, there is evidence confirming the involvement of PlGF in the progression of atherosclerosis and in the development of acute coronary syndrome. In this connection, the problem of investigating the efficiency and safety of possible use of PlGF preparations, as well as its place in the diagnosis of coronary heart disease and acute coronary syndrome remains urgent

Function of endothelium at adolescents with constitutional exogenous obesity before and after rehabilitation

OpenAIRE

Miroshnichenko, O.

2011-01-01

Function of endothelium at 43 adolescents with constitutional exogenous obesity before rehabilitation and at 33 healthy adolescents has been studied. Disorder of endothelial function has been established in 32 (74.4%) adolescents with constitutional exogenous obesity and in 7 (21.2%) healthy adolescents. We showed the efficiency of the rehabilitation program on restoration of endothelial function at adolescents with constitutional exogenous obesity.

[Prevention of coronary heart disease: smoking].

Science.gov (United States)

Heitzer, T; Meinertz, T

2005-01-01

Smoking is the leading preventable cause of illness and premature death in Germany, claiming over 110,000 lives a year because it directly increases the risk of dying from heart disease, stroke, emphysema and a variety of cancers. The overwhelming majority of smokers begin tobacco use before they reach adulthood. Among those young people who smoke, the average age is now 13-14. In Germany, about 39% of male and 31% of female adults (age 18-60 years) continue to smoke, despite information about the unequivocally negative health consequences of smoking. The exact mechanisms of smoking-related vascular disease are not yet known. Smoking causes acute hemodynamic alterations such as increase in heart rate, systematic and coronary vascular resistance, myocardial contractility, and myocardial oxygen demand. These short-term effects could lower the ischemic threshold in smokers with coronary artery disease and contribute to the increased risk for acute cardiovascular events. Endothelial damage is thought to be an initiating event in atherosclerosis and early studies have demonstrated that long-term smoking has direct toxic effects with structural changes of human endothelial cells. Recent research has shown the importance of the functional role of the endothelium in regulating vascular tone, platelet-endothelial interactions, leukocyte adhesion and smooth muscle cell proliferation via synthesis and release of a variety of substances such as nitric oxide. There is strong evidence that smoking leads to endothelial dysfunction mainly by increased inactivation of nitric oxide by oxygen-derived free radicals. Smoking also increases oxidative modification of LDL and is associated with lower HDL plasma levels. Smoking induces a systemic inflammatory response with increased leukocyte count and elevation of the C-reactive protein level. Importantly, the prothrombotic effects of smoking have been repeatedly demonstrated to cause alterations in platelet function, imbalance of

The independent relationship between triglycerides and coronary heart disease.

Science.gov (United States)

Morrison, Alan; Hokanson, John E

2009-01-01

The aim was to review epidemiologic studies to reassess whether serum levels of triglycerides should be considered independently of high-density lipoprotein-cholesterol (HDL-C) as a predictor of coronary heart disease (CHD). We systematically reviewed population-based cohort studies in which baseline serum levels of triglycerides and HDL-C were included as explanatory variables in multivariate analyses with the development of CHD (coronary events or coronary death) as dependent variable. A total of 32 unique reports describing 38 cohorts were included. The independent association between elevated triglycerides and risk of CHD was statistically significant in 16 of 30 populations without pre-existing CHD. Among populations with diabetes mellitus or pre-existing CHD, or the elderly, triglycerides were not significantly independently associated with CHD in any of 8 cohorts. Triglycerides and HDL-C were mutually exclusive predictors of coronary events in 12 of 20 analyses of patients without pre-existing CHD. Epidemiologic studies provide evidence of an association between triglycerides and the development of primary CHD independently of HDL-C. Evidence of an inverse relationship between triglycerides and HDL-C suggests that both should be considered in CHD risk estimation and as targets for intervention.

[Development of an automated processing method to detect coronary motion for coronary magnetic resonance angiography].

Science.gov (United States)

Asou, Hiroya; Imada, N; Sato, T

2010-06-20

On coronary MR angiography (CMRA), cardiac motions worsen the image quality. To improve the image quality, detection of cardiac especially for individual coronary motion is very important. Usually, scan delay and duration were determined manually by the operator. We developed a new evaluation method to calculate static time of individual coronary artery. At first, coronary cine MRI was taken at the level of about 3 cm below the aortic valve (80 images/R-R). Chronological change of the signals were evaluated with Fourier transformation of each pixel of the images were done. Noise reduction with subtraction process and extraction process were done. To extract higher motion such as coronary arteries, morphological filter process and labeling process were added. Using these imaging processes, individual coronary motion was extracted and individual coronary static time was calculated automatically. We compared the images with ordinary manual method and new automated method in 10 healthy volunteers. Coronary static times were calculated with our method. Calculated coronary static time was shorter than that of ordinary manual method. And scan time became about 10% longer than that of ordinary method. Image qualities were improved in our method. Our automated detection method for coronary static time with chronological Fourier transformation has a potential to improve the image quality of CMRA and easy processing.

Congenital coronary-pulmonary artery fistula originating from right and left coronary artery

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Ali Kemal Gür

2013-12-01

Full Text Available Coronary artery fistula (CAF is a rare congenital anomalywith an incidence of 1 in 50 000 live births. The fistula wasobserved at the right coronary artery in 53%, the left coronaryartery in 42% and both coronary artery in 5% of thecases. Echocardiography examination in a 46 year-oldwoman with the symptoms of chest pain, palpitation anddyspnea revealed a severe mitral valve insufficiency anda moderate to severe tricuspid valve insufficiency. A CAForiginating from the proximal part of the left anterior descendingartery (LAD and another fistula originating fromosteal part of the right coronary artery (RCA were detectedby coronary angiography. Both fistulas were draininginto the main pulmonary artery. The coronary artery fistulaclosed under cardiopulmonary by-pass. Mitral insufficiencyoriginated from the posterior leaflet was diagnosedintra-operative exploration, and thereafter it was repairedwith mitral annuloplasty including a quadrangular resectionand use of a 32 No St Jude mitral ring. Tricuspid valvewas repaired with Calangos Ring annuloplasty. Followingsix day hospital stay, the woman was discharged free ofany symptom.Key words: Dyspnea, double arteriovenous fistula, mitral and tricuspid insufficiency

Selective coronary scintigraphy

International Nuclear Information System (INIS)

Gambini, D.-J.

1975-01-01

Isotopic techniques occupy a leading place amongst examinations practicable on coronary patients because of their reliability and the safety and simplicity of their use. The present work reviews the possible applications of selective coronary scintigraphy in pathology. After a brief discussion on scintigraphy, isotopic techniques for myocardium research, coronarography and other methods to study local myocardium perfusion the theoretical bases for the use of the exploration are studied, the techniques and methods employed are reported and the results discussed. Coronary scintigraphy consists of selective injection in the two coronary arteries previously catheterized during a coronarography, of two different populations of microspheres labelled with two physically short-lived indicators: 15μ 99m Tc-labelled serumalbumin microspheres, 10 to 15μ In-labelled siderophiline microspheres. Various studies have shown the complete harmlessness of the exploration when certain precautions are taken regarding the size and number of the spheres. The microspheres disperse into the downstream arterial territory proportionally to the number of capillaries present in the different parts of the irrigated region, and are temporarily stopped in the precapillaries. The preparation of the different images needed to interpret the Face and OAG examination for the left coronary, then for the right coronary, is carried out at the end of the coronarography and lasts about 45 minutes. It is also possible by selective injection in the aorta-coronary bridges to judge their functional condition by observation of the regions they irrigate. 56 patients of the Necker hospital cardiological clinic have been examined [fr

Injuries to the vascular endothelium: vascular wall and endothelial dysfunction.

Science.gov (United States)

Fisher, Mark

2008-01-01

Vascular endothelial injury has multiple elements, and this article focuses on ischemia-related processes that have particular relevance to ischemic stroke. Distinctions between necrotic and apoptotic cell death provide a basic science context in which to better understand the significance of classical core and penumbra concepts of acute stroke, with apoptotic processes particularly prominent in the penumbra. The mitochondria are understood to serve as a reservoir of proteins that mediate apoptosis. Oxidative stress pathways generating reactive oxygen species (ROS) are prominent in endothelial injury, both ischemic and nonischemic, with prominent roles of enzyme- and nonenzymemediated pathways; mitochondria once again have a critical role, particularly in the nonenzymatic pathways generating ROS. Inflammation also contributes to vascular endothelial injury, and endothelial cells have the capacity to rapidly increase expression of inflammatory mediators following ischemic challenge; this leads to enhanced leukocyte-endothelial interactions mediated by selectins and adhesion molecules. Preconditioning consists of a minor version of an injurious event, which in turn may protect vascular endothelium from injury following a more substantial event. Presence of the blood-brain barrier creates unique responses to endothelial injury, with permeability changes due to impairment of endothelial-matrix interactions compounding altered vasomotor tone and tissue perfusion mediated by nitric oxide. Pharmacological protection against vascular endothelial injury can be provided by several of the phosphodiesterases (cilostazol and dipyridamole), along with statins. Optimal clinical responses for protection of brain vascular endothelium may use preconditioning as a model, and will likely require combined protection against apoptosis, ROS, and inflammation.

Physiologic assessment of coronary artery fistula

Energy Technology Data Exchange (ETDEWEB)

Gupta, N.C.; Beauvais, J. (Creighton Univ., Omaha, NE (USA))

1991-01-01

Coronary artery fistula is an uncommon clinical entity. The most common coronary artery fistula is from the right coronary artery to the right side of the heart, and it is less frequent to the pulmonary artery. The effect of a coronary artery fistula may be physiologically significant because of the steal phenomenon resulting in coronary ischemia. Based on published reports, it is recommended that patients with congenital coronary artery fistulas be considered candidates for elective surgical correction to prevent complications including development of congestive heart failure, angina, subacute bacterial endocarditis, myocardial infarction, and coronary aneurysm formation with rupture or embolization. A patient is presented in whom treadmill-exercise thallium imaging was effective in determining the degree of coronary steal from a coronary artery fistula, leading to successful corrective surgery.

Physiologic assessment of coronary artery fistula

International Nuclear Information System (INIS)

Gupta, N.C.; Beauvais, J.

1991-01-01

Coronary artery fistula is an uncommon clinical entity. The most common coronary artery fistula is from the right coronary artery to the right side of the heart, and it is less frequent to the pulmonary artery. The effect of a coronary artery fistula may be physiologically significant because of the steal phenomenon resulting in coronary ischemia. Based on published reports, it is recommended that patients with congenital coronary artery fistulas be considered candidates for elective surgical correction to prevent complications including development of congestive heart failure, angina, subacute bacterial endocarditis, myocardial infarction, and coronary aneurysm formation with rupture or embolization. A patient is presented in whom treadmill-exercise thallium imaging was effective in determining the degree of coronary steal from a coronary artery fistula, leading to successful corrective surgery

Coronary plaque quantification and fractional flow reserve by coronary computed tomography angiography identify ischaemia-causing lesions

DEFF Research Database (Denmark)

Gaur, Sara; Øvrehus, Kristian Altern; Dey, Damini

2016-01-01

AIMS: Coronary plaque characteristics are associated with ischaemia. Differences in plaque volumes and composition may explain the discordance between coronary stenosis severity and ischaemia. We evaluated the association between coronary stenosis severity, plaque characteristics, coronary computed...... tomography angiography (CTA)-derived fractional flow reserve (FFRCT), and lesion-specific ischaemia identified by FFR in a substudy of the NXT trial (Analysis of Coronary Blood Flow Using CT Angiography: Next Steps). METHODS AND RESULTS: Coronary CTA stenosis, plaque volumes, FFRCT, and FFR were assessed...

Nitric oxide-dependent vasodilation and Ca2+ signalling induced by erythrodiol in rat aorta

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Fidèle Ntchapda

2015-06-01

Full Text Available Objective: To evaluate the pharmacological property of erythrodiol, a natural triterpenoid contained in propolis, as vasodilatory agent, and to determine its mechanism of action. Methods: Rats aortic rings were isolated and suspended in organ baths, and the effects of erythrodiol were studied by means of isometric tension recording experiments. Nitric oxide (NO was detected by ozone-induced chemiluminescence. The technique used to evaluate changes in intracellular Ca2+ concentration in intact endothelium was opened aortic ring and loaded with 16 µmol Fura-2/AM for 60 min at room temperature, washed and fixed by small pins with the luminal face up. In situ, ECs were visualized by an upright epifluorescence Axiolab microscope (Carl Zeiss, Oberkochen, Germany equipped with a Zeiss×63 Achroplan objective (water immersion, 2.0 mm working distance, 0.9 numerical apertures. ECs were excited alternately at 340 and 380 nm, and the emitted light was detected at 510 nm. Results: In aortic rings with intact endothelium pre-contracted with norepinephrine (10-4 mol/L, the addition of erythrodiol (10-8-10-4 mol/L induced vasorelaxation in a concentration-dependent manner; in endothelium-denuded rings, the relaxant response induced by erythrodiol was almost completely abolished suggesting that vasorelaxation was endothelium-dependent. They had almost no relaxant effect on depolarised or endothelium-denuded aortic segments. The relaxation was significantly attenuated by pre-treatment with the NO synthase inhibitor Nvnitro-L-arginine-methylester. Erythrodiol (10-4 mol/L was able to significantly increase NOx levels. This effect was completely abolished after removal of the vascular endothelium. Erythrodiol (100 µmol/L caused a slow, long-lasting increase in intracellular Ca2+ concentration. These results further supported the hypothesis that erythrodiol can induce activation of the NO/soluble guanylate cyclase/cyclic guanosine monophosphate pathway, as

The association between the apolipoprotein B/A-I ratio and coronary calcification may differ depending on kidney function in a healthy population.

Directory of Open Access Journals (Sweden)

Seok-Hyung Kim

Full Text Available The apolipoprotein B/A-1 ratio has been reported to be one of the strongest risk predictors of cardiovascular events. However, its prognostic value for cardiovascular disease is still uncertain, especially in patients with chronic kidney disease. This study aimed to investigate whether the association between the apolipoprotein B/A-I ratio and coronary artery calcification differed according to kidney function in a healthy population.Of the data from 7,780 participants from the medical records database in Gangnam Severance Hospital from 2005 through 2016, a cross-sectional analysis included participants with an estimated glomerular filtration rate (eGFR ≥ 60 mL/min/1.73 m2 determined based on the Chronic Kidney Disease -Epidemiology Collaboration equation (n  =  1,800. Mild renal insufficiency was defined as an eGFR of 60-90 mL/min/1.73 m2. Coronary artery calcification measured with computed tomography was defined as an above-zero score. Logistic regression analyses were used to determine the association between coronary calcification and the apolipoprotein B/A-I ratio according to eGFR by adjusting for the influence of confounders.The mean apolipoprotein B/A-I level was significantly higher in the participants with coronary artery calcification than in the participants without coronary artery calcification. The apolipoprotein B/A-I ratio was significantly different according to coronary artery calcification in the participants with normal kidney function, but in the participants with mild renal insufficiency, it was not different. After adjusting for age, male sex, systolic blood pressure, body mass index, current smoking status, and fasting plasma glucose, the apolipoprotein B/A-I ratio was significantly associated with an increased risk of coronary artery calcification in participants with normal kidney function (odds ratio = 2.411, p = 0.011, while in the participants with mild renal insufficiency, the apolipoprotein B/A-I ratio was

Coronary heart disease

Science.gov (United States)

Heart disease, Coronary heart disease, Coronary artery disease; Arteriosclerotic heart disease; CHD; CAD ... buildup of plaque in the arteries to your heart. This may also be called hardening of the ...

Coronary artery anatomy and variants

Energy Technology Data Exchange (ETDEWEB)

Malago, Roberto; Pezzato, Andrea; Barbiani, Camilla; Alfonsi, Ugolino; Nicoli, Lisa; Caliari, Giuliana; Pozzi Mucelli, Roberto [Policlinico G.B. Rossi, University of Verona, Department of Radiology, Verona (Italy)

2011-12-15

Variants and congenital anomalies of the coronary arteries are usually asymptomatic, but may present with severe chest pain or cardiac arrest. The introduction of multidetector CT coronary angiography (MDCT-CA) allows the detection of significant coronary artery stenosis. Improved performance with isotropic spatial resolution and higher temporal resolution provides a valid alternative to conventional coronary angiography (CCA) in many patients. MDCT-CA is now considered the ideal tool for three-dimensional visualization of the complex and tortuous anatomy of the coronary arteries. With multiplanar and volume-rendered reconstructions, MDCT-CA may even outperform CCA in determining the relative position of vessels, thus providing a better view of the coronary vascular anatomy. The purpose of this review is to describe the normal anatomy of the coronary arteries and their main variants based on MDCT-CA with appropriate reconstructions. (orig.)

Coronary artery anomalies in Turner Syndrome.

Science.gov (United States)

Viuff, Mette H; Trolle, Christian; Wen, Jan; Jensen, Jesper M; Nørgaard, Bjarne L; Gutmark, Ephraim J; Gutmark-Little, Iris; Mortensen, Kristian H; Gravholt, Claus Højbjerg; Andersen, Niels H

Congenital heart disease, primarily involving the left-sided structures, is often seen in patients with Turner Syndrome. Moreover, a few case reports have indicated that coronary anomalies may be more prevalent in Turner Syndrome than in the normal population. We therefore set out to systematically investigate coronary arterial anatomy by computed tomographic coronary angiography (coronary CTA) in Turner Syndrome patients. Fifty consecutive women with Turner Syndrome (mean age 47 years [17-71]) underwent coronary CTA. Patients were compared with 25 gender-matched controls. Coronary anomaly was more frequent in patients with Turner Syndrome than in healthy controls [20% vs. 4% (p = 0.043)]. Nine out of ten abnormal cases had an anomalous left coronary artery anatomy (absent left main trunk, n = 7; circumflex artery originating from the right aortic sinus, n = 2). One case had a tubular origin of the right coronary artery above the aortic sinus. There was no correlation between the presence of coronary arterial anomalies and karyotype, bicuspid aortic valve, or other congenital heart defects. Coronary anomalies are highly prevalent in Turner Syndrome. The left coronary artery is predominantly affected, with an absent left main coronary artery being the most common anomaly. No hemodynamically relevant coronary anomalies were found. Copyright © 2016 Society of Cardiovascular Computed Tomography. All rights reserved.

Coronary stent on coronary CT angiography: Assessment with model-based iterative reconstruction technique

Energy Technology Data Exchange (ETDEWEB)

Lee, Eun Chae; Kim, Yeo Koon; Chun, Eun Ju; Choi, Sang IL [Dept. of of Radiology, Seoul National University Bundang Hospital, Seongnam (Korea, Republic of)

2016-05-15

To assess the performance of model-based iterative reconstruction (MBIR) technique for evaluation of coronary artery stents on coronary CT angiography (CCTA). Twenty-two patients with coronary stent implantation who underwent CCTA were retrospectively enrolled for comparison of image quality between filtered back projection (FBP), adaptive statistical iterative reconstruction (ASIR) and MBIR. In each data set, image noise was measured as the standard deviation of the measured attenuation units within circular regions of interest in the ascending aorta (AA) and left main coronary artery (LM). To objectively assess the noise and blooming artifacts in coronary stent, we additionally measured the standard deviation of the measured attenuation and intra-luminal stent diameters of total 35 stents with dedicated software. All image noise measured in the AA (all p < 0.001), LM (p < 0.001, p = 0.001) and coronary stent (all p < 0.001) were significantly lower with MBIR in comparison to those with FBP or ASIR. Intraluminal stent diameter was significantly higher with MBIR, as compared with ASIR or FBP (p < 0.001, p = 0.001). MBIR can reduce image noise and blooming artifact from the stent, leading to better in-stent assessment in patients with coronary artery stent.

Large coronary intramural hematomas

DEFF Research Database (Denmark)

Antonsen, Lisbeth; Thayssen, Per; Jensen, Lisette Okkels

2015-01-01

Isolated spontaneous coronary intramural hematoma is a unique subset of spontaneous coronary artery dissection that is characterized by a hemorrhage limited to the medial-adventitial layers, causing subsequent hematoma formation without visible intimal flaps. It is an infrequent and serious...... diagnostics and treatment strategy. Coronary intramural hematomas can also occur iatrogenically, as a complication to percutaneous coronary intervention (PCI). Coronary angiography (CAG) has limited diagnostic value in the absence of intimal dissections, and lesions are often angiographically ambiguous....... Intravascular ultrasound (IVUS) is an important diagnostic tool in establishing the correct diagnosis, as it provides a complete vessel wall assessment, and enables morphometric information regarding the magnitude and severity of the underlying hematoma. Due to the rarity of this clinical scenario...

Multislice CT coronary angiography: effect of sublingual nitroglycerine on the diameter of coronary arteries

International Nuclear Information System (INIS)

Dewey, M.; Hamm, B.; Hoffmann, H.

2006-01-01

Purpose: to investigate the influence of sublingual glycerol trinitrate (1.2 mg, Nitrate [nitroglycerine], Nitrolingual N spray) on the coronary artery diameter on multislice computed tomography (MSCT) coronary angiography. Materials and methods: out of our database of patients who underwent MSCT (slice thickness of 0.5 mm, Aquilion, Toshiba) coronary angiography between July 2003 and November 2005 (950 patients) we retrospectively identified patients with follow-up examinations who received Nitrate for one examination while another examination was performed without Nitrate (10 patients). Another 10 patients who underwent two MSCT examinations with sublingual Nitrate administration were randomly selected from this database to serve as control group. For the resulting 40 MSCT examinations, blinded MSCT datasets were prepared, which were randomly evaluated by a reader blinded to the patient information and whether or not Nitrate had been given. The proximal coronary artery diameters were measured for the left main coronary artery (LMA), the left anterior descending coronary artery (LAD), the left circumflex coronary artery (LCX), and the right coronary artery (RCA) in all 40 datasets, resulting in altogether 160 measurements. Results: the proximal diameters of all four coronary arteries were significantly larger on the MSCT coronary angiograms obtained after sublingual administration of Nitrate compared with the examinations in the same 10 patients without Nitrate (p < 0.001). The average diameters without and with Nitrate for the LMA, LAD, LCX, and RCA were 4.3 ± 1.1 vs. 4.8 ± 0.9 mm (12% increase, p < 0.005), 3.0 ± 0.6 vs. 3.5 ± 0.5 mm (17% increase, p < 0.001), 2.7 ± 0.6 vs. 3.2 ± 0.7 mm (19% increase, p < 0.005), and 2.9 ± 0.9 vs. 3.5 ± 0.7 mm (21% increase, p < 0.005), respectively. In the control group of 10 patients who underwent two MSCT coronary angiographies after sublingual Nitrate, no significant difference in the proximal diameter of all four

Breath-hold two-dimensional MR angiography of coronary arteries. Comparison with conventional coronary angiography in ten cases

International Nuclear Information System (INIS)

Li Liwei; Zhang Wanshi; Liu Chaozhong; Lu Xiaoyan; Xu Jiaxing

1997-01-01

Purpose: To assess the diagnostic value of two-dimensional coronary magnetic resonance (MR) angiography in patients evaluated for ischemic heart disease. Materials and methods: Ten patients who underwent selective cardiac catheterization with coronary MR angiography were evaluated with two-dimensional coronary MR angiography. Coronary MR angiography was performed with breath-hold fat-suppressed ECG-gated Turbo-FLASH with K-space segmentation using a 1.5 T imager. Results: The left main coronary artery, proximal left anterior descending artery, circumflex artery and right coronary artery were demonstrated in all cases. Continuous segments (mean) of left anterior descending, circumflex and right coronary arteries visualized on MRA were 6.72 +- 3.16 cm, 3.67 +- 4.81 cm and 7.93 +- 3.12 cm respectively. The overall sensitivity for detection of hemodynamically significant coronary artery lesion (≥50%) was 62.5% respectively. Conclusion: Breath-hold two-dimensional coronary MR angiography was useful in showing relatively long segments of the main coronary arteries and also has potential in depicting hemodynamically significant coronary artery lesions

[Vasoprotective effect of adaptation to hypoxia in myocardial ischemia and reperfusion injury].

Science.gov (United States)

Manukhina, E B; Terekhina, O L; Belkina, L M; Abramochkin, D V; Budanova, O P; Mashina, S Yu; Smirin, B V; Yakunina, E B; Downey, H F

2013-01-01

Adaptation to hypoxia is known to be cardioprotective in ischemic and reperfusion (IR) injury of the myocardium. This study was focused on investigating a possibility for prevention of endothelial dysfunction in IR injury of the rat heart using adaptation to intermittent hypoxia, which was performed in a cyclic mode (5-10 min of hypoxia interspersed with 4 min of normoxia, 5-8 cycles daily) for 21 days. Endothelial function of coronary blood vessels was evaluated after the in vitro IR of isolated heart (15 min of ischemia and 10 min of reperfusion) by the increment of coronary flow rate in response to acetylcholine. Endothelium-dependent relaxation of isolated rat aorta was evaluated after the IR myocardial injury in situ (30 min of ischemia and 60 min of reperfusion) by a relaxation response of noradrenaline-precontracted vessel rings to acetylcholine. The following major results were obtained in this study: 1) IR myocardial injury induced endothelial dysfunction of coronary blood vessels and the aorta, a non-coronary blood vessel, remote from the IR injury area; and 2) adaptation to hypoxia prevented the endothelial dysfunction of both coronary and non-coronary blood vessels associated with the IR injury. Therefore, adaptation to hypoxia is not only cardioprotective but also vasoprotective in myocardial IR injury.

[Giant coronary aneurysms in infants with Kawasaki disease].

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Sánchez Andrés, Antonio; Salvador Mercader, Inmaculada; Seller Moya, Julia; Carrasco Moreno, José Ignacio

2017-08-01

Kawasaki disease (KD) is an acute vasculitis of unknown origin and predominant in males. The long-term effects of the disease depend on whether there are coronary lesions, particularly aneurysms. The prognosis of patients with giant aneurysms is very poor due to their natural progression to coronary thrombosis or severe obstructive lesions. A series of 8 cases is presented where the epidemiology and diagnostic methods are described. The treatment of the acute and long-term cardiovascular sequelae is also reviewed. A descriptive analysis was conducted on patients admitted to the Paediatric Cardiology Unit of La Fe University Hospital (Valencia) with KD and a coronary lesion. More than one artery was involved in all patients. Although early diagnosis was established in only two cases, none of the patients had severe impairment of ventricular function during the acute phase. Treatment included intravenous gammaglobulin and acetylsalicylic acid at anti-inflammatory doses during the acute phase. A combination of dual antiplatelet therapy and corticosteroids was given in cases of coronary thrombosis. The silent aneurysms continue to persist. KD is the most common cause of acquired heart disease in children. The delay in diagnosis is associated with a greater likelihood of coronary lesions that could increase the risk of cardiovascular events in adulthood. Thus, this subgroup requires close clinical monitoring for a better control of cardiovascular risk factors over time. Copyright © 2016 Asociación Española de Pediatría. Publicado por Elsevier España, S.L.U. All rights reserved.

Comparison and Supervised Learning of Segmentation Methods Dedicated to Specular Microscope Images of Corneal Endothelium

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Yann Gavet

2014-01-01

Full Text Available The cornea is the front of the eye. Its inner cell layer, called the endothelium, is important because it is closely related to the light transparency of the cornea. An in vivo observation of this layer is performed by using specular microscopy to evaluate the health of the cells: a high spatial density will result in a good transparency. Thus, the main criterion required by ophthalmologists is the cell density of the cornea endothelium, mainly obtained by an image segmentation process. Different methods can perform the image segmentation of these cells, and the three most performing methods are studied here. The question for the ophthalmologists is how to choose the best algorithm and to obtain the best possible results with it. This paper presents a methodology to compare these algorithms together. Moreover, by the way of geometric dissimilarity criteria, the algorithms are tuned up, and the best parameter values are thus proposed to the expert ophthalmologists.

Accumulation of the Vitamin D Precursor Cholecalciferol Antagonizes Hedgehog Signaling to Impair Hemogenic Endothelium Formation

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Mauricio Cortes

2015-10-01

Full Text Available Hematopoietic stem and progenitor cells (HSPCs are born from hemogenic endothelium in the dorsal aorta. Specification of this hematopoietic niche is regulated by a signaling axis using Hedgehog (Hh and Notch, which culminates in expression of Runx1 in the ventral wall of the artery. Here, we demonstrate that the vitamin D precursor cholecalciferol (D3 modulates HSPC production by impairing hemogenic vascular niche formation. Accumulation of D3 through exogenous treatment or inhibition of Cyp2r1, the enzyme required for D3 25-hydroxylation, results in Hh pathway antagonism marked by loss of Gli-reporter activation, defects in vascular niche identity, and reduced HSPCs. Mechanistic studies indicated the effect was specific to D3, and not active 1,25-dihydroxy vitamin D3, acting on the extracellular sterol-binding domain of Smoothened. These findings highlight a direct impact of inefficient vitamin D synthesis on cell fate commitment and maturation in Hh-regulated tissues, which may have implications beyond hemogenic endothelium specification.

[Myocardial bridge as the only cause of acute coronary syndrome among the young patients].

Science.gov (United States)

Miakinkova, Liudmila O; Teslenko, Yurii V; Tsyhanenko, Irina V

2018-01-01

Introduction: Myocardial bridge is an inborn anomaly of coronary artery development, when a part of it is submerged in a myocard, which is pressing the coronary artery to a systola and restrains coronary blood circulation. Generally this feature of coronary blood circulation does not cause any clinical symptoms because the 85% of coronary blood stream of the left ventricle is provided by diastolic filling. Hemodynamic changes in atherosclerosis, tahicardie, hypertrophie of myocard are leading to the manifestation of clinical symptoms of ischemia. The aim: The purpose of the investigation was to discover the features of clinical development of acute coronary syndrome caused by myocardial bridge of young patients without the features of atherosclerotical harm of coronary arteries. Materials and methods: Eight causes of acute coronary syndrome among patients of 28±8,5 years with myocardial bridge which was revealed during coronary angiography, were investigated. Standardized examination and conservative treatment of patients was held, except for three who have got interventional therapy. Results: According to our investigation, myocardial bridge of all investigated patients was located in the middle of the third front interventricular branch of the left coronary artery. Causes of acute coronary syndrome manifestation were tahicardia, spasms of coronary artery, inducted by iatrogenic factors hypertrophie of myocard, hypertrophic cardiomyopatie. Connection between the manifestation of clinical symptoms and length of tunneled segment which did not depend on the level of systolic compres was discovered. The results of conservative and interventional treatment were analyzed. Conclusions: Myocardial bridge can be the cause of myocardial ischemia among patients without signs of coronary atherosclerosis with additional hemodynamic risk facts such as tahicardia, spasms of coronary artery, hypertrophie of myocard. Clinical symptomatology of the acute coronary syndrome is more

Location-dependent coronary artery diffusive and convective mass transport properties of a lipophilic drug surrogate measured using nonlinear microscopy.

Science.gov (United States)

Keyes, Joseph T; Simon, Bruce R; Vande Geest, Jonathan P

2013-04-01

Arterial wall mass transport properties dictate local distribution of biomolecules or locally delivered dugs. Knowing how these properties vary between coronary artery locations could provide insight into how therapy efficacy is altered between arterial locations. We introduced an indocarbocyanine drug surrogate to the lumens of left anterior descending and right coronary (LADC; RC) arteries from pigs with or without a pressure gradient. Interstitial fluorescent intensity was measured on live samples with multiphoton microscopy. We also measured binding to porcine coronary SMCs in monoculture. Diffusive transport constants peaked in the middle sections of the LADC and RC arteries by 2.09 and 2.04 times, respectively, compared to the proximal and distal segments. There was no statistical difference between the average diffusivity value between LADC and RC arteries. The convection coefficients had an upward trend down each artery, with the RC being higher than the LADC by 3.89 times. This study demonstrates that the convective and diffusive transport of lipophilic molecules changes between the LADC and the RC arteries as well as along their length. These results may have important implications in optimizing drug delivery for the treatment of coronary artery disease.

Current status of hybrid coronary revascularization.

Science.gov (United States)

Jaik, Nikhil P; Umakanthan, Ramanan; Leacche, Marzia; Solenkova, Natalia; Balaguer, Jorge M; Hoff, Steven J; Ball, Stephen K; Zhao, David X; Byrne, John G

2011-10-01

Hybrid coronary revascularization combines coronary artery bypass surgery with percutaneous coronary intervention techniques to treat coronary artery disease. The potential benefits of such a technique are to offer the patients the best available treatments for coronary artery disease while minimizing the risks of the surgery. Hybrid coronary revascularization has resulted in the establishment of new 'hybrid operating suites', which incorporate and integrate the capabilities of a cardiac surgery operating room with that of an interventional cardiology laboratory. Hybrid coronary revascularization has greatly augmented teamwork and cooperation between both fields and has demonstrated encouraging as well as good initial outcomes.

Ropivacaine-Induced Contraction Is Attenuated by Both Endothelial Nitric Oxide and Voltage-Dependent Potassium Channels in Isolated Rat Aortae

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Seong-Ho Ok

2013-01-01

Full Text Available This study investigated endothelium-derived vasodilators and potassium channels involved in the modulation of ropivacaine-induced contraction. In endothelium-intact rat aortae, ropivacaine concentration-response curves were generated in the presence or absence of the following inhibitors: the nonspecific nitric oxide synthase (NOS inhibitor Nω-nitro-L-arginine methyl ester (L-NAME, the neuronal NOS inhibitor Nω-propyl-L-arginine hydrochloride, the inducible NOS inhibitor 1400W dihydrochloride, the nitric oxide-sensitive guanylyl cyclase (GC inhibitor ODQ, the NOS and GC inhibitor methylene blue, the phosphoinositide-3 kinase inhibitor wortmannin, the cytochrome p450 epoxygenase inhibitor fluconazole, the voltage-dependent potassium channel inhibitor 4-aminopyridine (4-AP, the calcium-activated potassium channel inhibitor tetraethylammonium (TEA, the inward-rectifying potassium channel inhibitor barium chloride, and the ATP-sensitive potassium channel inhibitor glibenclamide. The effect of ropivacaine on endothelial nitric oxide synthase (eNOS phosphorylation in human umbilical vein endothelial cells was examined by western blotting. Ropivacaine-induced contraction was weaker in endothelium-intact aortae than in endothelium-denuded aortae. L-NAME, ODQ, and methylene blue enhanced ropivacaine-induced contraction, whereas wortmannin, Nω-propyl-L-arginine hydrochloride, 1400W dihydrochloride, and fluconazole had no effect. 4-AP and TEA enhanced ropivacaine-induced contraction; however, barium chloride and glibenclamide had no effect. eNOS phosphorylation was induced by ropivacaine. These results suggest that ropivacaine-induced contraction is attenuated primarily by both endothelial nitric oxide and voltage-dependent potassium channels.

Milrinone infusion: A therapeutic option in coronary vasospasm after primary percutaneous transluminal coronary angioplasty

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Singh Amarpal

2009-01-01

Full Text Available A 42-year-old male presented to the emergency department with acute chest pain. The electrocardiogram revealed inferior wall myocardial infarction. Emergency coronary angiography revealed total occlusion of the distal right coronary artery with thrombus. Patient was taken up for primary percutaneous coronary angioplasty with stenting of distal right coronary artery. Six hours following the procedure, the patient developed re-elevation of ST-segment in inferior leads of electrocardiogram and subsequent haemodynamic instability. Repeat coronary angiography revealed patent stent and coronary artery spasm in proximal part, which was relieved by intracoronary injection of nitroglycerine. After an hour, the patient re-developed symptoms of chest pain along with bradycardia, hypotension and ST segment elevation. Intravenous infusion of nitroglycerine did not improve the condition but produced persistent hypotension. Infusion of milrinone was then started. Over time, normalisation of electrocardiogram occurred. The patient was discharged in stable condition. This case suggests that milrinone may be effective in alleviating coronary artery spasm when the use of other agents fails

A Case of Cardiac Cephalalgia Showing Reversible Coronary Vasospasm on Coronary Angiogram

Science.gov (United States)

Yang, YoungSoon; Jin, Dong Gyu; Jang, Il Mi; Jang, YoungHee; Na, Hae Ri; Kim, SanYun

2010-01-01

Background Under certain conditions, exertional headaches may reflect coronary ischemia. Case Report A 44-year-old woman developed intermittent exercise-induced headaches with chest tightness over a period of 10 months. Cardiac catheterization followed by acetylcholine provocation demonstrated a right coronary artery spasm with chest tightness, headache, and ischemic effect of continuous electrocardiography changes. The patient's headache disappeared following intra-arterial nitroglycerine injection. Conclusions A coronary angiogram with provocation study revealed variant angina and cardiac cephalalgia, as per the International Classification of Headache Disorders (code 10.6). We report herein a patient with cardiac cephalalgia that manifested as reversible coronary vasospasm following an acetylcholine provocation test. PMID:20607049

Impact of coronary dominance on in-hospital outcomes after percutaneous coronary intervention in patients with acute coronary syndrome.

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Toshiki Kuno

Full Text Available OBJECTIVE: This study evaluated the manner in which coronary dominance affects in-hospital outcomes of acute coronary syndrome (ACS patients undergoing percutaneous coronary intervention (PCI. BACKGROUND: Previous studies have shown that left dominant coronary anatomies are associated with worse prognoses in patients with coronary artery disease. METHODS: Data were analyzed from 4873 ACS patients undergoing PCI between September 2008 and April 2013 at 14 hospitals participating in the Japanese Cardiovascular Database Registry. The patients were grouped based on diagnostic coronary angiograms performed prior to PCI; those with right- or co-dominant anatomy (RD group and those with left-dominant anatomy (LD group. RESULTS: The average patient age was 67.6±11.8 years and both patient groups had similar ages, coronary risk factors, comorbidities, and prior histories. The numbers of patients presenting with symptoms of heart failure, cardiogenic shock, or cardiopulmonary arrest were significantly higher in the LD group than in the RD group (heart failure: 650 RD patients [14.7%] vs. 87 LD patients [18.8%], P = 0.025; cardiogenic shock: 322 RD patients [7.3%] vs. 48 LD patients [10.3%], P = 0.021; and cardiopulmonary arrest: 197 RD patients [4.5%] vs. 36 LD patients [7.8%], P = 0.003. In-hospital mortality was significantly higher among LD patients than among RD patients (182 RD patients [4.1%] vs. 36 LD patients [7.8%], P = 0.001. Multivariate logistic regression analysis revealed that LD anatomy was an independent predictor for in-hospital mortality (odds ratio, 1.75; 95% confidence interval, 1.06-2.89; P = 0.030. CONCLUSION: Among ACS patients who underwent PCI, LD patients had significantly worse in-hospital outcomes compared with RD patients, and LD anatomy was an independent predictor of in-hospital mortality.

[Endarterectomy of the coronary arteries].

Science.gov (United States)

Fischer, V; Simkovic, I; Holoman, M; Verchvodko, P; Janotík, P; Galbánek, J; Hulman, M; Kostelnicák, J; Jurco, R; Slezák, J

1992-02-01

The authors analyze 50 patients with endarterectomy of the coronary arteries during the periods of 1972-1974 and 1988-1990. The results of endarterectomy of the right and left coronary artery provide evidence of its justification in indicated cases whereby contrary to some departments the results of endarterectomy of the left coronary artery are comparable with endarterectomy of the right coronary artery.

Heterogeneity and weak coupling may explain the synchronization characteristics of cells in the arterial wall

DEFF Research Database (Denmark)

Jacobsen, Jens Christian Brings; Aalkjær, Christian; Matchkov, Vladimir

2008-01-01

development of force known as vasomotion. We present experimental data showing a considerable heterogeneity in cellular calcium dynamics in the vascular wall. In stimulated vessels, some SMCs remain quiescent, whereas others display waves of variable frequency. At the onset of vasomotion, all SMCs...

Detection of coronary calcium with electron beam tomography in coronary artery disease

International Nuclear Information System (INIS)

Haberl, R.; Knez, A.; Becker, A.; Becker, C.; Bruening, R.; Reiser, M.; Maass, A.; Steinbeck, G.

1998-01-01

Purpose: Coronary calcium is a powerful indicator of arteriosclerosis and can be detected very precisely with electron beam tomography. The method can be applied in patients with known coronary artery disease or in asymptomatic patients at risk of arteriosclerotic disease. Results: At the University of Munich we performed an EBT scan of the heart in 1100 patients within the last year. In 567 patients coronary angiography was performed also (±3 days). Confirming previous reports in the literature, we found a correlation of the calcium score with the age and gender of the patients. Severe coronary artery disease (stenoses ≥ 75%) was associated with significantly more calcium than less severe CAD. The calcium score did not discriminate between one-, two- and three-vessel disease. The site of calcification does not correlate with the localization of stenoses. Thirty-three percent of the patients with significant coronary artery disease showed a normal age-adjusted calcium score; a total of 8.1% of patients with severe stenoses did not reveal any coronary calcification (score =0). With asymptomatic patients there are only a few studies available. Soft plaques cannot be detected with EBT, but in most patients soft plaques occur together with hard plaques. Our results show that spiral CT of the newest generation may also be used for calcium screening. There was an excellent correlation of the calcium scores of EBT and spiral CT at all levels of calcification. Discussion: Coronary calcium is a sensitive marker of coronary artery disease. In the clinical setting EBT is indicated in patients with known coronary artery disease (to evaluate prognosis), in patients who are unable to perform a stress test, and in patients with atypical chest pain. However, lack of calcification may be associated with severe stenoses in a minority of patients. The clinical value in asymptomatic patients needs to be defined: Randomized studies are necessary. We see a possible indication in

Visualization of coronary venous anatomy by cardiovascular magnetic resonance

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Crean Andrew

2009-08-01

Full Text Available Abstract Background Coronary venous imaging with whole-heart cardiovascular magnetic resonance (CMR angiography has recently been described using developmental pulse sequences and intravascular contrast agents. However, the practical utility of coronary venous imaging will be for patients with heart failure in whom cardiac resynchronisation therapy (CRT is being considered. As such complementary information on ventricular function and myocardial viability will be required. The aim of this study was to determine if the coronary venous anatomy could be depicted as part of a comprehensive CMR protocol and using a standard extracellular contrast agent. Methods and Results Thirty-one 3D whole heart CMR studies, performed after intravenous administration of 0.05 mmol/kg gadolinium DTPA, were reviewed. The cardiac venous system was visualized in all patients. The lateral vein of the left ventricle was present in 74%, the anterior interventricular vein in 65%, and the posterior interventricular vein in 74% of patients. The mean maximum distance of demonstrable cardiac vein on the 3D images was 81.5 mm and was dependent on the quality of the 3D data set. Five patients showed evidence of myocardial infarction on late gadolinium enhancement (LGE images. Conclusion Coronary venous anatomy can be reliably demonstrated using a comprehensive CMR protocol and a standard extracellular contrast agent. The combination of coronary venous imaging, assessment of ventricular function and LGE may be useful in the management of patients with LV dysfunction being considered for CRT.

Treatment of Angina and Microvascular Coronary Dysfunction

Science.gov (United States)

Samim, Arang; Nugent, Lynn; Mehta, Puja K.; Shufelt, Chrisandra; Merz, C. Noel Bairey

2014-01-01

Opinion statement Microvascular coronary dysfunction (MCD) is an increasingly recognized cause of cardiac ischemia and angina, more commonly diagnosed in women. Patients with MCD present with the triad of persistent chest pain, ischemic changes on stress testing, and no obstructive coronary artery disease (CAD) on cardiac catheterization. Data from National Heart, Lung and Blood Institute (NHLBI)-sponsored Women’s Ischemia Syndrome Evaluation (WISE) study has shown that the diagnosis of MCD is not benign, with a 2.5% annual risk of adverse cardiac events including myocardial infarction, stroke, congestive heart failure, or death. The gold standard diagnostic test for MCD is an invasive coronary reactivity test (CRT), which uses acetylcholine, adenosine, and nitroglycerin to test the endothelial dependent and independent, microvascular and macrovascular coronary function. The CRT allows for diagnostic and treatment options as well as further risk stratifying patients for future cardiovascular events. Treatment of angina and MCD should be aimed at ischemia disease management to reduce risk of adverse cardiac events, ameliorating symptoms to improve quality of life, and to decrease the morbidity from unnecessary and repeated cardiac catheterization in patients with open coronary arteries. A comprehensive treatment approach aimed at risk factor managment, including lifestyle counseling regarding smoking cessation, nutrition and physical activity should be initiated. Current pharmacotherapy for MCD can include the treatment of microvascular endothelial dysfunction (statins, angiotensin-converting enzyme inhibitor, low dose aspirin), as well as treatment for angina and myocardial ischemia (beta blockers, calcium channel blockers, nitrates, ranolazine). Additional symptom management techniques can include tri-cyclic medication, enhanced external counterpulsation, autogenic training, and spinal cord stimulation. While our current therapies are effective in the treatment

Multiple giant coronary aneurysms arising from coronary istula to the pulmonary artery revealed in aorta CT angiography

Energy Technology Data Exchange (ETDEWEB)

Kang, Eun Ju; Lee, Ki Nam [Dept. of Radiology, Dong A University Hospital, Dong-A University College of Medicine, Busan (Korea, Republic of); Lee, Jong Min [Dept. of Radiology, Kyungpook National University Hospital, Kyungpook National University College of Medicine, Daegu (Korea, Republic of)

2015-12-15

Coronary fistula is a rare coronary abnormality through which blood drains into the cardiac chamber, great vessel or other vessels. In addition, giant aneurysm arising from coronary fistula is rare pathologic manifestation. Herein, we presented a rare case of multiple giant coronary artery aneurysms arising from coronary to pulmonary artery fistula in a 79-year-old woman presenting with sudden loss of consciousness. The aneurysms were detected using thoracic computed tomography angiography and consequently confirmed by invasive coronary angiography.

Determining the proportion of coronary segments assessable on 16-slice CT coronary angiography: a brief report

International Nuclear Information System (INIS)

Soon, K. H.; Cox, N.; Eccleston, D.; Lim, Y.; Chaitowitz, I.; Bell, K. W.; Kelly, A-M.

2007-01-01

Computed tomography coronary angiography (CT-CA) is becoming a popular non-invasive coronary imaging method. We aimed to determine the proportion of coronary segments assessable on a 16-slice CT in comparison with conventional selective coronary angiography (SCA). We identified all patients who had both 16-slice CT-CA and recent SCA (less than 12 months) from March 2004 to July 2005. Two CT reporters blinded to SCA independently classified coronary segment assessability on CT-CA. A cardiologist blinded to CT findings classified assess-ability of coronary segments on SCA. Data were analysed using descriptive statistics and proportion of agreement. Ninety-five study pairs were included in the analysis. Of those, 1161 coronary segments were deemed assessable on SCA and 1103 segments (95%) were also assessable on CT-CA. Nonassessable segments on CT-CA were predominantly in the distal segments and branches of coronary arteries. Reasons for nonassessability were small calibre (48.3%), motion artefacts (20.7%) and poorly reconstructed segments (22.4%). The 16-slice CT was able to assess a high proportion of but not all coronary segments. Nonassessable segments were predominantly distal segments or branches of coronary arteries. Motion artefacts due to heart-rate changes, small calibre and poorly reconstructed images were main causes of nonassessability on 16-slice CT-CA

Relationship of Hypertension to Coronary Atherosclerosis and Cardiac Events in Patients With Coronary Computed Tomographic Angiography.

Science.gov (United States)

Nakanishi, Rine; Baskaran, Lohendran; Gransar, Heidi; Budoff, Matthew J; Achenbach, Stephan; Al-Mallah, Mouaz; Cademartiri, Filippo; Callister, Tracy Q; Chang, Hyuk-Jae; Chinnaiyan, Kavitha; Chow, Benjamin J W; DeLago, Augustin; Hadamitzky, Martin; Hausleiter, Joerg; Cury, Ricardo; Feuchtner, Gudrun; Kim, Yong-Jin; Leipsic, Jonathon; Kaufmann, Philipp A; Maffei, Erica; Raff, Gilbert; Shaw, Leslee J; Villines, Todd C; Dunning, Allison; Marques, Hugo; Pontone, Gianluca; Andreini, Daniele; Rubinshtein, Ronen; Bax, Jeroen; Jones, Erica; Hindoyan, Niree; Gomez, Millie; Lin, Fay Y; Min, James K; Berman, Daniel S

2017-08-01

Hypertension is an atherosclerosis factor and is associated with cardiovascular risk. We investigated the relationship between hypertension and the presence, extent, and severity of coronary atherosclerosis in coronary computed tomographic angiography and cardiac events risk. Of 17 181 patients enrolled in the CONFIRM registry (Coronary CT Angiography Evaluation for Clinical Outcomes: An International Multicenter Registry) who underwent ≥64-detector row coronary computed tomographic angiography, we identified 14 803 patients without known coronary artery disease. Of these, 1434 hypertensive patients were matched to 1434 patients without hypertension. Major adverse cardiac events risk of hypertension and non-hypertensive patients was evaluated with Cox proportional hazards models. The prognostic associations between hypertension and no-hypertension with increasing degree of coronary stenosis severity (nonobstructive or obstructive ≥50%) and extent of coronary artery disease (segment involvement score of 1-5, >5) was also assessed. Hypertension patients less commonly had no coronary atherosclerosis and more commonly had nonobstructive and 1-, 2-, and 3-vessel disease than the no-hypertension group. During a mean follow-up of 5.2±1.2 years, 180 patients experienced cardiac events, with 104 (2.0%) occurring in the hypertension group and 76 (1.5%) occurring in the no-hypertension group (hazard ratios, 1.4; 95% confidence intervals, 1.0-1.9). Compared with no-hypertension patients without coronary atherosclerosis, hypertension patients with no coronary atherosclerosis and obstructive coronary disease tended to have higher risk of cardiac events. Similar trends were observed with respect to extent of coronary artery disease. Compared with no-hypertension patients, hypertensive patients have increased presence, extent, and severity of coronary atherosclerosis and tend to have an increase in major adverse cardiac events. © 2017 American Heart Association, Inc.

Coronary CT angiography

Energy Technology Data Exchange (ETDEWEB)

Dewey, Marc [Charite - Universitaetsmedizin Berlin (Germany). Inst. fuer Radiologie

2009-07-01

Coronary CT angiography has attained increasing scientific attention at academic institutions and has become a highly accurate diagnostic modality. Extending this knowledge into a practice setting is the purpose of 'Coronary CT Angiography'. This book will assist you in integrating cardiac CT into your daily practice, while also giving an overview of the current technical status and applications. The specific features of scanners from all four main vendors are also presented providing an objective overview of noninvasive coronary angiography using CT. (orig.)

Coffee consumption and coronary calcification: The Rotterdam coronary calcification study

NARCIS (Netherlands)

G.J. van Woudenbergh (Geertruida); R. Vliegenthart (Rozemarijn); F.J.A. van Rooij (Frank); A. Hofman (Albert); M. Oudkerk (Matthijs); J.C.M. Witteman (Jacqueline); J.M. Geleijnse (Marianne)

2008-01-01

textabstractBACKGROUND - The role of coffee in the cardiovascular system is not yet clear. We examined the relation of coffee intake with coronary calcification in a population-based cohort. METHODS AND RESULTS - The study involved 1570 older men and women without coronary heart disease who

Uptake of low density lipoproteins by the hamster lung. Interactions with capillary endothelium

International Nuclear Information System (INIS)

Nistor, A.; Simionescu, M.

1986-01-01

The mechanism by which the circulating low density lipoproteins (LDL) contribute to the lung surfactant cholesterol was investigated by perfusing the hamster lung in situ with LDL either radiolabeled or coupled to gold, or both. Part of [ 125 I]-LDL and [ 3 H]-cholesterol LDL were taken up by a specific process which was time- and concentration-dependent and reached saturation within 20 to 30 min of perfusion. Competition experiments and removal of receptor-bound LDL by heparin suggested that about 50% of LDL uptake is receptor-independent. Experiments using double labeled LDL showed a preferential uptake of 3 H-cholesterol versus 125 I by the lung both in situ and in vivo. LDL-gold particles (LDL-Au), recirculated through the isolated lung, bound to the endothelial luminal plasma membrane and to features potentially involved in receptor-mediated endocytosis (coated pits, coated vesicles, lysosomelike structures) and in transcytosis (plasmalemmal vesicles). The results suggest that LDL uptake by the lung takes place by both receptor-mediated and receptor-independent mechanisms. Cholesterol may be in part transferred to the lung without the apoprotein moiety; the alveolar capillary endothelium appears to be the first monitor of this complex process

Evaluation of Coronary Artery Stenosis by Quantitative Flow Ratio During Invasive Coronary Angiography

DEFF Research Database (Denmark)

Westra, Jelmer; Tu, Shengxian; Winther, Simon

2018-01-01

BACKGROUND: Quantitative flow ratio (QFR) is a novel diagnostic modality for functional testing of coronary artery stenosis without the use of pressure wires and induction of hyperemia. QFR is based on computation of standard invasive coronary angiographic imaging. The purpose of WIFI II (Wire...... patients with suspected coronary artery disease on coronary computed tomographic angiography for diagnostic invasive coronary angiography. Fractional flow reserve (FFR) was measured in all segments with 30% to 90% diameter stenosis. Blinded observers calculated QFR (Medis Medical Imaging bv......, The Netherlands) for comparison with FFR. FFR was measured in 292 lesions from 191 patients. Ten (5%) and 9 patients (5%) were excluded because of FFR and angiographic core laboratory criteria, respectively. QFR was successfully computed in 240 out of 255 lesions (94%) with a mean diameter stenosis of 50...

Relation of coronary vasoreactivity and coronary calcification in asymptomatic subjects with a family history of premature coronary artery disease

International Nuclear Information System (INIS)

Pirich, Christian; Leber, Alexander; Knez, Andreas; Bengel, Frank M.; Nekolla, Stephan G.; Schwaiger, Markus; Haberl, Ralph

2004-01-01

Electron-beam computed tomography (EBCT) allows non-invasive imaging of coronary calcification and has been promoted as a screening tool for coronary artery disease (CAD) in asymptomatic high-risk subjects. This study assessed the relation of coronary calcifications to alterations in coronary vascular reactivity by means of positron emission tomography (PET) in asymptomatic subjects with a familial history of premature CAD. Twenty-one subjects (mean age 51±10 years) underwent EBCT imaging for coronary calcifications expressed as the coronary calcium score (CCS according to Agatston) and rest/adenosine-stress nitrogen-13 ammonia PET with quantification of myocardial blood flow (MBF) and coronary flow reserve (CFR). The mean CCS was 237±256 (median 146, range 0-915). The CCS was 100 units in 13. As defined by age-related thresholds, 15 subjects had an increased CCS (>75th percentile). Overall mean resting and stress MBF and CFR were 71±16 ml 100 g -1 min -1 , 218±54 ml 100 g -1 min -1 and 3.20±0.77, respectively. Three subjects with CCS ranging from 114 to 451 units had an abnormal CFR (<2.5). There was no relation between CCS and resting or stress MBF or CFR (r=0.17, 0.18 and 0.10, respectively). In asymptomatic subjects a pathological CCS was five times more prevalent than an abnormal CFR. The absence of any close relationship between CCS and CFR reflects the fact that quantitative myocardial perfusion imaging with PET characterises the dynamic process of vascular reactivity while EBCT is a measure of more stable calcified lesions in the arterial wall whose presence is closely related to age. (orig.)

Rest period duration of the coronary arteries: Implications for magnetic resonance coronary angiography

International Nuclear Information System (INIS)

Shechter, Guy; Resar, Jon R.; McVeigh, Elliot R.

2005-01-01

Magnetic resonance (MR) and computed tomography coronary imaging is susceptible to artifacts caused by motion of the heart. The presence of rest periods during the cardiac and respiratory cycles suggests that images free of motion artifacts could be acquired. In this paper, we studied the rest period (RP) duration of the coronary arteries during a cardiac contraction and a tidal respiratory cycle. We also studied whether three MR motion correction methods could be used to increase the respiratory RP duration. Free breathing x-ray coronary angiograms were acquired in ten patients. The three-dimensional (3D) structure of the coronary arteries was reconstructed from a biplane acquisition using stereo reconstruction methods. The 3D motion of the arterial model was then recovered using an automatic motion tracking algorithm. The motion field was then decomposed into separate cardiac and respiratory components using a cardiac respiratory parametric model. For the proximal-to-middle segments of the right coronary artery (RCA), a cardiac RP (<1 mm 3D displacement) of 76±34 ms was measured at end systole (ES), and 65±42 ms in mid-diastole (MD). The cardiac RP was 80±25 ms at ES and 112±42 ms at MD for the proximal 5 cm of the left coronary tree. At end expiration, the respiratory RP (in percent of the respiratory period) was 26±8% for the RCA and 27±17% for the left coronary tree. Left coronary respiratory RP (<0.5 mm 3D displacement) increased with translation (32% of the respiratory period), rigid body (51%), and affine (79%) motion correction. The RCA respiratory RP using translational (27%) and rigid body (33%) motion correction were not statistically different from each other. Measurements of the cardiac and respiratory rest periods will improve our understanding of the temporal and spatial resolution constraints for coronary imaging

Optimal timing of coronary invasive strategy in non-ST-segment elevation acute coronary syndromes

DEFF Research Database (Denmark)

Navarese, Eliano P; Gurbel, Paul A; Andreotti, Felicita

2013-01-01

The optimal timing of coronary intervention in patients with non-ST-segment elevation acute coronary syndromes (NSTE-ACSs) is a matter of debate. Conflicting results among published studies partly relate to different risk profiles of the studied populations.......The optimal timing of coronary intervention in patients with non-ST-segment elevation acute coronary syndromes (NSTE-ACSs) is a matter of debate. Conflicting results among published studies partly relate to different risk profiles of the studied populations....

Critical stenosis of a right ventricle to coronary artery fistula seen at dual-source CT in a newborn with pulmonary atresia and intact ventricular septum

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Seguela, Pierre-Emmanuel [Centre Chirurgical Marie Lannelongue, Department of Pediatric Cardiology, Le Plessis-Robinson (France); Hopital des Enfants, Toulouse Cedex 9 (France); Houyel, Lucile; Piot, Jean-Dominique [Centre Chirurgical Marie Lannelongue, Department of Pediatric Cardiology, Le Plessis-Robinson (France); Loget, Philippe [Centre Hospitalier Universitaire de Rennes, Department of Pathology, Rennes (France); Paul, Jean-Francois [Centre Chirurgical Marie Lannelongue, Department of Pediatric Radiology, Le Plessis-Robinson (France)

2011-08-15

We report the case of a newborn with pulmonary atresia with intact ventricular septum and right ventricle-dependent coronary circulation. He died several weeks after a Blalock-Taussig procedure because of a progressive stenosis of the main coronary artery. We present echocardiographic and dual-source CT images of the stenosis, with autopsy correlation. To our knowledge, CT images of this quality have never been reported in a newborn. This case illustrates the extreme difficulty in prognosticating the outcome for these patients and underlines the need for a detailed neonatal coronary mapping to assess right ventricle-dependent coronary circulation. (orig.)

Coffee consumption and coronary calcification - The Rotterdam Coronary Calcification Study

NARCIS (Netherlands)

van Woudenbergh, Geertruida J.; Vliegenthart, Rozemarijn; van Rooij, Frank J. A.; Hofman, Albert; Oudkerk, Matthijs; Witteman, Jacqueline C. M.; Geleijnse, Johanna M.

Background-The role of coffee in the cardiovascular system is not yet clear. We examined the relation of coffee intake with coronary calcification in a population-based cohort. Methods and Results-The study involved 1570 older men and women without coronary heart disease who participated in the

Reproducibility of coronary calcification detection with electron-beam computed tomography

International Nuclear Information System (INIS)

Hernigou, A.; Challande, P.; Boudeville, J.C.; Sene, V.; Grataloup, C.; Plainfosse, M.

1996-01-01

If coronary calcification scores obtained with electron-beam computed tomography (EBT) were proved to be correlated to coronary atherosclerosis, the reproducibility of the technique had to be assessed before being useed for patient follow-up. A total of 150 patients, selected as a result of a cholesterol screening programme, were studied by EBT. Twelve contiguous 3-mm-thick transverse slices beginning on the proximal coronary arteries were obtained through the base of the heart. The amount of calcium was evaluated as the calcified area weighted by a coefficient depending on the density peak level. The value was expressed as a logarithmic scale. Intra-observer, inter-observer and inter-examination reproducibilities were calculated. They were 1.9, 1.3 and 7.2%, respectively. These results were good enough to allow the use of EBT for longitudinal studies. The influence of acquisition and calculation conditions on score computation were also analysed. (orig.)

The independent relationship between triglycerides and coronary heart disease

Science.gov (United States)

Morrison, Alan; Hokanson, John E

2009-01-01

Aims: The aim was to review epidemiologic studies to reassess whether serum levels of triglycerides should be considered independently of high-density lipoprotein-cholesterol (HDL-C) as a predictor of coronary heart disease (CHD). Methods and results: We systematically reviewed population-based cohort studies in which baseline serum levels of triglycerides and HDL-C were included as explanatory variables in multivariate analyses with the development of CHD (coronary events or coronary death) as dependent variable. A total of 32 unique reports describing 38 cohorts were included. The independent association between elevated triglycerides and risk of CHD was statistically significant in 16 of 30 populations without pre-existing CHD. Among populations with diabetes mellitus or pre-existing CHD, or the elderly, triglycerides were not significantly independently associated with CHD in any of 8 cohorts. Triglycerides and HDL-C were mutually exclusive predictors of coronary events in 12 of 20 analyses of patients without pre-existing CHD. Conclusions: Epidemiologic studies provide evidence of an association between triglycerides and the development of primary CHD independently of HDL-C. Evidence of an inverse relationship between triglycerides and HDL-C suggests that both should be considered in CHD risk estimation and as targets for intervention. PMID:19436658

Flexibility and trackability of laser cut coronary stent systems.

Science.gov (United States)

Szabadíts, Péter; Puskás, Zsolt; Dobránszky, János

2009-01-01

Coronary stents are the most important supports in present day cardiology. Flexibility and trackability are two basic features of stents. In this paper, four different balloon-expandable coronary stent systems were investigated mechanically in order to compare their suitability. The coronary stent systems were assessed by measurements of stent flexibility as well as by comparison of forces during simulated stenting in a self-investigated coronary vessel model. The stents were cut by laser from a single tube of 316L stainless steel or L-605 (CoCr) cobalt chromium alloy. The one-and four-point bending tests were carried out to evaluate the stent flexibility E x I (Nmm(2)), under displacement control in crimped and expanded configurations. The flexibility of stents would be rather dependent on the design than on raw material. In general a more flexible stent needs lower tracking force during the implantation. The L-605 raw material stents need lower track force to pass through in the vessel model than the 316L raw material stents. The sort and long stents passed through the curved vessel model in different ways. The long stents nestled to the vessel wall at the outer arc and bent, while the short stents did not bend in the curve, only the delivery systems bent.

Hyperglycemia and Diabetes Downregulate the Functional Expression of TRPV4 Channels in Retinal Microvascular Endothelium

Science.gov (United States)

Monaghan, Kevin; McNaughten, Jennifer; McGahon, Mary K.; Kelly, Catriona; Kyle, Daniel; Yong, Phaik Har

2015-01-01

Retinal endothelial cell dysfunction is believed to play a key role in the etiology and pathogenesis of diabetic retinopathy. Numerous studies have shown that TRPV4 channels are critically involved in maintaining normal endothelial cell function. In the current paper, we demonstrate that TRPV4 is functionally expressed in the endothelium of the retinal microcirculation and that both channel expression and activity is downregulated by hyperglycaemia. Quantitative PCR and immunostaining demonstrated molecular expression of TRPV4 in cultured bovine retinal microvascular endothelial cells (RMECs). Functional TRPV4 activity was assessed in cultured RMECs from endothelial Ca2+-responses recorded using fura-2 microfluorimetry and electrophysiological recordings of membrane currents. The TRPV4 agonist 4α-phorbol 12,13-didecanoate (4-αPDD) increased [Ca2+]i in RMECs and this response was largely abolished using siRNA targeted against TRPV4. These Ca2+-signals were completely inhibited by removal of extracellular Ca2+, confirming their dependence on influx of extracellular Ca2+. The 4-αPDD Ca2+-response recorded in the presence of cyclopiazonic acid (CPA), which depletes the intracellular stores preventing any signal amplification through store release, was used as a measure of Ca2+-influx across the cell membrane. This response was blocked by HC067047, a TRPV4 antagonist. Under voltage clamp conditions, the TRPV4 agonist GSK1016790A stimulated a membrane current, which was again inhibited by HC067047. Following incubation with 25mM D-glucose TRPV4 expression was reduced in comparison with RMECs cultured under control conditions, as were 4αPDD-induced Ca2+-responses in the presence of CPA and ion currents evoked by GSK1016790A. Molecular expression of TRPV4 in the retinal vascular endothelium of 3 months’ streptozotocin-induced diabetic rats was also reduced in comparison with that in age-matched controls. We conclude that hyperglycaemia and diabetes reduce the

Dependence of Intramyocardial Pressure and Coronary Flow on Ventricular Loading and Contractility: A Model Study

NARCIS (Netherlands)

Bovendeerd, P.H.M.; Borsje, P.; Arts, M.G.J.; Vosse, van de F.N.

2006-01-01

The phasic coronary arterial inflow during the normal cardiac cycle has been explained with simple (waterfall, intramyocardial pump) models, emphasizing the role of ventricular pressure. To explain changes in isovolumic and low afterload beats, these models were extended with the effect of

Presence of plasma proteins facilitates the uptake of 125I-thrombin by the rabbit thoracic aorta endothelium in vitro

International Nuclear Information System (INIS)

Hatton, M.W.; Moar, S.L.

1986-01-01

Various purified proteins, protein derivatives and two polysaccharides were added individually to a physiological medium in order to effect uptake of 125 I-thrombin by the rabbit aorta endothelium. Over a wide range of concentration (0.004-40 mg/ml), the presence of either purified rabbit or bovine albumin during thrombin uptake encouraged an increase (70-110%) in 125 I-thrombin binding by the endothelium and subendothelium compared to uptake by aorta segments in the absence of added protein. Pretreatment of aorta segments with albumin before incubation with 125 I-thrombin in the absence of albumin did not encourage thrombin uptake to the same extent as having 125 I-thrombin and albumin together. Purified human transferrin, rabbit IgG, chicken ovalbumin or denatured bovine casein could replace albumin to produce a similar enhancement of thrombin uptake. Replacing active concentrations of albumin by either reduced-carboxymethylated albumin, defatted albumin, plasmin-treated or thermolysin-treated albumin also caused an increase (50-130%) in thrombin binding, whereas replacement by acid-hydrolysed albumin or with polyglutamic acid was either ineffective or even inhibitory. Lysine-modified or arginine-modified albumins caused a small enhancement (14-32%) and no enhancement of thrombin uptake, respectively. Dextran, at low concentration (0.04-0.4 mg/ml) did not influence thrombin uptake, and at higher concentration (4-40 mg/ml) caused a decrease in uptake by both the endothelium and subendothelial layers. Low concentration of dextran sulphate inhibited thrombin uptake to 20-30% of control values. These data express the importance of accompanying protein in the response of the vascular endothelium during binding of thrombin. The possibility that other protein-cell interactions may be similarly influenced by macromolecular solutes is also discussed

Subclinical Coronary Plaque Burden in Asymptomatic Relatives of Patients With Documented Premature Coronary Artery Disease

DEFF Research Database (Denmark)

Christiansen, Morten Krogh; Jensen, Jesper Møller; Bøtker, Hans Erik

Introduction: A family history of premature coronary artery disease (CAD) is a well-known risk factor for adverse coronary events with age of onset being inversely related to the degree of heritability. Hypothesis: We hypothesized that asymptomatic first degree relatives, of patients with premature...... CAD, suffer a high burden of subclinical coronary atherosclerosis. Methods: First degree relatives, aged 30-65 years, of patients with a documented coronary revascularization procedure before the age of 40 years, were invited to participate in the study. Participants were matched by age, sex...... and absence of a family history, with patients referred for coronary CT angiography (CTA) because of atypical angina or non-anginal chest pain. A pooled blinded analysis was performed. The main outcome measure was the number of plaque-affected coronary segments. Results: 88 relatives and 88 symptomatic...

Coffee Consumption and Coronary Calcification: The Rotterdam Coronary Calcification Study

NARCIS (Netherlands)

Woudenbergh, van G.J.; Vliegenthart, R.; Rooij, van F.J.A.; Hofman, A.; Oudkerk, M.; Witteman, J.C.M.; Geleijnse, J.M.

2008-01-01

Background¿ The role of coffee in the cardiovascular system is not yet clear. We examined the relation of coffee intake with coronary calcification in a population-based cohort. Methods and Results¿ The study involved 1570 older men and women without coronary heart disease who participated in the

The Angio-Seal™ femoral closure device allows immediate ambulation after coronary angiography and percutaneous coronary intervention

DEFF Research Database (Denmark)

Hvelplund, Anders; Jeger, Raban; Osterwalder, Remo

2011-01-01

To test the safety of immediate mobilisation of patients undergoing coronary angiography and percutaneous coronary intervention (PCI) closed with Angio-Seal™ -a femoral vascular closure device.......To test the safety of immediate mobilisation of patients undergoing coronary angiography and percutaneous coronary intervention (PCI) closed with Angio-Seal™ -a femoral vascular closure device....

THE EFFECT OF WAIST CIRCUMFERENCES MORE THAN NORMAL ON THE INCIDENT OF CORONARY HEART DISEASE

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Pria Wahyu

2017-07-01

Full Text Available Introduction: Coronary heart disease is known as the most common disease that causes mortality in the world, one of the examination to identify the risks of coronary heart disease is measuring waist circumference. The purpose of this study was to identify correlation between large waist circumferences and the incident of coroner heart disease. Method: Design used in this study was analytic observational (retrospective with cross sectional approach. There were 63 respondents which sampling by simple random sampling. The independent variable was waist circumferences and the dependent variable was coronary heart disease. Data were collected by direct observation then analyzed by spearman correlation statistic test with significance level α≤0.05. Result: The result showed that waist circumferences more than normal had significant correlation with the incident of coronary heart disease (p=0.02. Analysis: It can be concluded that there was correlation between waist circumferences more than normal and the incident of coronary heart disease to the clients with coroner cardiac disease. Discussion: Earlier screening and detection is needed to prevent coronary heart disease.

Clinical aspects of coronary heart diseases without myocardial infarction and in the chronic infarction phase

International Nuclear Information System (INIS)

Kober, G.

1984-01-01

Reductions in coronary vessel diameters of more than 50% are usually caused by atherosclerosis, seldom by predominant spasme. They can lead via an inadequate myocardial perfusion to angina pectoris. Whereas in patients with organic coronary stenoses exertional angina is typical, patients with coronary spasms usually tend to angina at rest. Depending on the symptoms, a stable or unstable angina can be distinguished from the status anginosus and a variant form of angina. During anginal attacks signs of myocardial ischemia can often be seen in the electrocardiogram. This applies to patients with and without earlier myocardial infarctions. When pathologic ECG-changes can already be seen in the ECG at rest, difficulties often arise during evaluation of the exercise-ECG. In those cases, diagnosis can be improved by additional investigations, especially with radionuclear techniques. For a conclusive diagnosis, left heart catheterization and a functional coronary angiography is necessary. Coronary heart disease can be treated either by drug therapy, coronary angioplasty or bypass surgery. The same diagnostic procedures are suitable for the evaluation of a therapeutical success and for primary diagnosis. (orig.) [de

Optimization of coronary attenuation in coronary computed tomography angiography using diluted contrast material.

Science.gov (United States)

Kawaguchi, Naoto; Kurata, Akira; Kido, Teruhito; Nishiyama, Yoshiko; Kido, Tomoyuki; Miyagawa, Masao; Ogimoto, Akiyoshi; Mochizuki, Teruhito

2014-01-01

The purpose of this study was to evaluate a personalized protocol with diluted contrast material (CM) for coronary computed tomography angiography (CTA). One hundred patients with suspected coronary artery disease underwent retrospective electrocardiogram-gated coronary CTA on a 256-slice multidetector-row CT scanner. In the diluted CM protocol (n=50), the optimal scan timing and CM dilution rate were determined by the timing bolus scan, with 20% CM dilution (5ml/s during 10s) being considered suitable to achieve the target arterial attenuation of 350 Hounsfield units (HU). In the body weight (BW)-adjusted protocol (n=50, 222mg iodine/kg), only the optimal scan timing was determined by the timing bolus scan. The injection rate and volume in the timing bolus scan and real scan were identical between the 2 protocols. We compared the means and variations in coronary attenuation between the 2 protocols. Coronary attenuation (mean±SD) in the diluted CM and BW-adjusted protocols was 346.1±23.9 HU and 298.8±45.2 HU, respectively. The diluted CM protocol provided significantly higher coronary attenuation and lower variance than did the BW-adjusted protocol (P<0.05, in each). The diluted CM protocol facilitates more uniform attenuation on coronary CTA in comparison with the BW-adjusted protocol.  

High-Dose Polymerized Hemoglobin Fails to Alleviate Cardiac Ischemia/Reperfusion Injury due to Induction of Oxidative Damage in Coronary Artery.

Science.gov (United States)

Yang, Qian; Wu, Wei; Li, Qian; Chen, Chan; Zhou, Ronghua; Qiu, Yanhua; Luo, Ming; Tan, Zhaoxia; Li, Shen; Chen, Gang; Zhou, Wentao; Liu, Jiaxin; Yang, Chengmin; Liu, Jin; Li, Tao

2015-01-01

Objective. Ischemia/reperfusion (I/R) injury is an unavoidable event for patients in cardiac surgery under cardiopulmonary bypass (CPB). This study was designed to investigate whether glutaraldehyde-polymerized human placenta hemoglobin (PolyPHb), a hemoglobin-based oxygen carrier (HBOC), can protect heart against CPB-induced I/R injury or not and to elucidate the underlying mechanism. Methods and Results. A standard dog CPB model with 2-hour cardiac arrest and 2-hour reperfusion was established. The results demonstrated that a low-dose PolyPHb (0.1%, w/v) provided a significant protection on the I/R heart, whereas the high-dose PolyPHb (3%, w/v) did not exhibit cardioprotective effect, as evidenced by the impaired cardiac function, decreased myocardial oxygen utilization, and elevated enzymes release and pathological changes. Further study indicated that exposure of isolated coronary arteries or human umbilical vein endothelial cells (HUVECs) to a high-dose PolyPHb caused impaired endothelium-dependent relaxation, which was companied with increased reactive oxygen species (ROS) production, reduced superoxide dismutase (SOD) activity, and elevated malonaldehyde (MDA) formation. Consistent with the increased oxidative stress, the NAD(P)H oxidase activity and subunits expression, including gp91(phox), p47(phox), p67(phox), and Nox1, were greatly upregulated. Conclusion. The high-dose PolyPHb fails to protect heart from CPB-induced I/R injury, which was due to overproduction of NAD(P)H oxidase-induced ROS and resultant endothelial dysfunction.

High-Dose Polymerized Hemoglobin Fails to Alleviate Cardiac Ischemia/Reperfusion Injury due to Induction of Oxidative Damage in Coronary Artery

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Qian Yang

2015-01-01

Full Text Available Objective. Ischemia/reperfusion (I/R injury is an unavoidable event for patients in cardiac surgery under cardiopulmonary bypass (CPB. This study was designed to investigate whether glutaraldehyde-polymerized human placenta hemoglobin (PolyPHb, a hemoglobin-based oxygen carrier (HBOC, can protect heart against CPB-induced I/R injury or not and to elucidate the underlying mechanism. Methods and Results. A standard dog CPB model with 2-hour cardiac arrest and 2-hour reperfusion was established. The results demonstrated that a low-dose PolyPHb (0.1%, w/v provided a significant protection on the I/R heart, whereas the high-dose PolyPHb (3%, w/v did not exhibit cardioprotective effect, as evidenced by the impaired cardiac function, decreased myocardial oxygen utilization, and elevated enzymes release and pathological changes. Further study indicated that exposure of isolated coronary arteries or human umbilical vein endothelial cells (HUVECs to a high-dose PolyPHb caused impaired endothelium-dependent relaxation, which was companied with increased reactive oxygen species (ROS production, reduced superoxide dismutase (SOD activity, and elevated malonaldehyde (MDA formation. Consistent with the increased oxidative stress, the NAD(PH oxidase activity and subunits expression, including gp91phox, p47phox, p67phox, and Nox1, were greatly upregulated. Conclusion. The high-dose PolyPHb fails to protect heart from CPB-induced I/R injury, which was due to overproduction of NAD(PH oxidase-induced ROS and resultant endothelial dysfunction.

Morphometry of the coronary ostia and the structure of coronary arteries in the shorthair domestic cat.

Directory of Open Access Journals (Sweden)

Karolina Barszcz

Full Text Available The aim of this study was to measure the area of the coronary ostia, assess their localization in the coronary sinuses and to determine the morphology of the stem of the left and right coronary arteries in the domestic shorthair cat. The study was conducted on 100 hearts of domestic shorthair cats of both sexes, aged 2-18 years, with an average body weight of 4.05 kg. A morphometric analysis of the coronary ostia was carried out on 52 hearts. The remaining 48 hearts were injected with a casting material in order to carry out a morphological assessment of the left and right coronary arteries. In all the studied animals, the surface of the left coronary artery ostium was larger than the surface of the right coronary artery ostium. There were four types of the left main coronary artery: type I (23 animals, 49%-double-branched left main stem (giving off the left circumflex branch and the interventricular paraconal branch, which in turn gave off the septal branch, type II (12 animals, 26%-double-branched left main stem (giving off the left circumflex branch and the interventricular paraconal branch without the septal branch, type III (11 animals, 23%-triple-branched left main stem (giving off the left circumflex branch, interventricular branch and the septal branch, type IV (1 animal, 2%-double-branched left main stem (giving off the interventricular paraconal branch and the left circumflex branch, which in turn gave off the septal branch. The left coronary artery ostium is greater than the right one. There is considerable diversity in the branches of proximal segment of the left coronary artery, while the right coronary artery is more conservative. These results can be useful in defining the optimal strategies in the endovascular procedures involving the coronary arteries or the aortic valve in the domestic shorthair cat.

Coronary heart disease risk assessment and characterization of coronary artery disease using coronary CT angiography: comparison of asymptomatic and symptomatic groups

International Nuclear Information System (INIS)

Hwang, Y.; Kim, Y.; Chung, I.-M.; Ryu, J.; Park, H.

2010-01-01

Aim: To evaluate the prevalence of coronary artery disease (CAD) in relation to risk of coronary heart disease (CHD) and assess plaque characteristics from coronary computed tomography (CT) angiography in asymptomatic and symptomatic patients. Materials and methods: Three hundred and ninety consecutive patients [asymptomatic group, n = 138; symptomatic group (atypical or non-anginal chest pain), n = 252] were retrospectively enrolled. They were subsequently classified into three CHD risk categories, based on the National Cholesterol Education Program guidelines, and 10 year risks of coronary events were calculated using Framingham risk score. CT was evaluated for stenosis, plaque composition, and coronary calcium scores. Results: CAD was observed in 42% of the asymptomatic group and 62% of the symptomatic group. In the former, the prevalence of CAD in low-, moderate- and high-risk subgroups was 21.4, 47.4 and 65%, respectively, and was 33.3, 74.4, and 72.4% in the symptomatic group. Framingham 10-year risks of coronary events were significantly higher in patients with CAD than in normal participants, and receiver operating characteristics curves showed that discriminatory power was poor in the asymptomatic group and symptomatic men, and good in symptomatic women. Of the participants in the asymptomatic group, 12% exhibited only non-calcified plaques and of the symptomatic group, 7% exhibited only non-calcified plaques. The coronary calcium score was significantly higher for significant stenosis than for non-significant stenosis in both groups. Conclusions: The prevalence of CAD was not negligible even in subgroups with low-to-moderate CHD risk. Additionally, the Framingham risk score was effective for predicting CAD only in symptomatic women. Coronary calcium scores correlated with significant stenosis; however, a sizeable percentage of both groups had only non-calcified plaques.

Coronary artery calcification in Kawasaki disease

International Nuclear Information System (INIS)

Ino, T.; Shimazaki, S.; Akimoto, K.; Park, I.; Nishimoto, K.; Yabuta, K.; Tanaka, A.

1990-01-01

To evaluate the angiographic features of coronary lesions in Kawasaki disease with coronary artery calcification, cinefluoroscopy and cineangiography were retrospectively reviewed in 116 patients who had undergone coronary angiography between 1982 and 1989. Angiographic abnormalities of coronary arteries were demonstrated in 55 of 116 patients. In 5 (9.1%) of the 55 patients, 9 with calcification were identified by cinefluoroscopy and chest X-ray. Eight of the 9 calcified lesions showed a circular or ring-shape configuration. Coronary angiography revealed a total occlusion of the right coronary artery with collateral circulation from the distal left coronary artery in 2 patients and a severe stenosis of the right coronary artery in 2 patients, in whom anticoagulant therapy had not been continued during the follow-up periods. The remaining patient in whom anticoagulant therapy had been continued had bilateral aneurysms but no significant stenosis. These results indicate that a ring-shape calcification on chest X-ray in 2 patients with a history of Kawasaki disease may suggest an involvement by coronary artery stenosis even when anticoagulant drugs had been given. Therefore, coronary angiography should be performed to evaluate the stenotic lesions if this type of calcification is found by routine radiographic examination. (orig.)

A factorial randomized controlled trial to evaluate the effect of micronutrients supplementation and regular aerobic exercise on maternal endothelium-dependent vasodilatation and oxidative stress of the newborn.

Science.gov (United States)

Ramírez-Vélez, Robinson; Romero, Miryam; Echeverri, Isabella; Ortega, José Guillermo; Mosquera, Mildrey; Salazar, Blanca; Girón, Sandra Lorena; Saldarriaga, Wilmar; Aguilar de Plata, Ana Cecilia; Mateus, Julio Cesar

2011-02-28

Many studies have suggested a relationship between metabolic abnormalities and impaired fetal growth with the development of non-transmissible chronic diseases in the adulthood. Moreover, it has been proposed that maternal factors such as endothelial function and oxidative stress are key mechanisms of both fetal metabolic alterations and subsequent development of non-transmissible chronic diseases. The objective of this project is to evaluate the effect of micronutrient supplementation and regular aerobic exercise on endothelium-dependent vasodilation maternal and stress oxidative of the newborn. 320 pregnant women attending to usual prenatal care in Cali, Colombia will be included in a factorial randomized controlled trial. Women will be assigned to the following intervention groups: 1. usual prenatal care (PC) and placebo (maltodextrine). 2. Exercise group: PC, placebo and aerobic physical exercise. 3. Micronutrients group: PC and a micronutrients capsule consisting of zinc (30 mg), selenium (70 μg), vitamin A (400 μg), alphatocopherol (30 mg), vitamin C (200 mg), and niacin (100 mg). 4. Combined interventions Group: PC, supplementation of micronutrients, and aerobic physical exercise. Anthropometric measures will be taken at the start and at the end of the interventions. Since in previous studies has been showed that the maternal endothelial function and oxidative stress are related to oxidative stress of the newborn, this study proposes that complementation with micronutrients during pregnancy and/or regular physical exercise can be an early and innovative alternative to strengthen the prevention of chronic diseases in the population. NCT00872365.

Coronary Artery Disease

DEFF Research Database (Denmark)

Christiansen, Morten Krogh

2017-01-01

A family history of coronary artery disease (CAD) is an important risk factor for adverse coronary events, in particular if the disease has an early onset. The risk of CAD is influenced by genetic and environmental factors with a greater genetic contribution earlier in life. Through recent years......), and to characterize and quantify subclinical atherosclerosis in their relatives. Furthermore, the aim was to explore the impact of common genetic risk variants on the age of onset, familial clustering and disease severity. In study I, 143 patients with early- onset CAD were recruited from the Western Denmark Heart...... Registry and risk factor control was evaluated. The study revealed that risk factors are common in early-onset CAD and that a large room for risk factor improvement remains. In study II, we used coronary computed tomography angiography to compare the coronary plaque burden and characteristics between 88...

Beneficial effects of calcitriol on hypertension, glucose intolerance, impairment of endothelium-dependent vascular relaxation, and visceral adiposity in fructose-fed hypertensive rats.

Science.gov (United States)

Chou, Chu-Lin; Pang, Cheng-Yoong; Lee, Tony J F; Fang, Te-Chao

2015-01-01

Besides regulating calcium homeostasis, the effects of vitamin D on vascular tone and metabolic disturbances remain scarce in the literature despite an increase intake with high-fructose corn syrup worldwide. We investigated the effects of calcitriol, an active form of vitamin D, on vascular relaxation, glucose tolerance, and visceral fat pads in fructose-fed rats. Male Wistar-Kyoto rats were divided into 4 groups (n = 6 per group). Group Con: standard chow diet for 8 weeks; Group Fru: high-fructose diet (60% fructose) for 8 weeks; Group Fru-HVD: high-fructose diet as Group Fru, high-dose calcitriol treatment (20 ng / 100 g body weight per day) 4 weeks after the beginning of fructose feeding; and Group Fru-LVD: high-fructose diet as Group Fru, low-dose calcitriol treatment (10 ng / 100 g body weight per day) 4 weeks after the beginning of fructose feeding. Systolic blood pressure was measured twice a week by the tail-cuff method. Blood was examined for serum ionized calcium, phosphate, creatinine, glucose, triglycerides, and total cholesterol. Intra-peritoneal glucose intolerance test, aortic vascular reactivity, the weight of visceral fat pads, adipose size, and adipose angiotensin II levels were analyzed at the end of the study. The results showed that the fructose-fed rats significantly developed hypertension, impaired glucose tolerance, heavier weight and larger adipose size of visceral fat pads, and raised adipose angiotensin II expressions compared with the control rats. High- and low-dose calcitriol reduced modestly systolic blood pressure, increased endothelium-dependent aortic relaxation, ameliorated glucose intolerance, reduced the weight and adipose size of visceral fat pads, and lowered adipose angiotensin II expressions in the fructose-fed rats. However, high-dose calcitriol treatment mildly increased serum ionized calcium levels (1.44 ± 0.05 mmol/L). These results suggest a protective role of calcitriol treatment on endothelial function, glucose

Beneficial effects of calcitriol on hypertension, glucose intolerance, impairment of endothelium-dependent vascular relaxation, and visceral adiposity in fructose-fed hypertensive rats.

Directory of Open Access Journals (Sweden)

Chu-Lin Chou

Full Text Available Besides regulating calcium homeostasis, the effects of vitamin D on vascular tone and metabolic disturbances remain scarce in the literature despite an increase intake with high-fructose corn syrup worldwide. We investigated the effects of calcitriol, an active form of vitamin D, on vascular relaxation, glucose tolerance, and visceral fat pads in fructose-fed rats. Male Wistar-Kyoto rats were divided into 4 groups (n = 6 per group. Group Con: standard chow diet for 8 weeks; Group Fru: high-fructose diet (60% fructose for 8 weeks; Group Fru-HVD: high-fructose diet as Group Fru, high-dose calcitriol treatment (20 ng / 100 g body weight per day 4 weeks after the beginning of fructose feeding; and Group Fru-LVD: high-fructose diet as Group Fru, low-dose calcitriol treatment (10 ng / 100 g body weight per day 4 weeks after the beginning of fructose feeding. Systolic blood pressure was measured twice a week by the tail-cuff method. Blood was examined for serum ionized calcium, phosphate, creatinine, glucose, triglycerides, and total cholesterol. Intra-peritoneal glucose intolerance test, aortic vascular reactivity, the weight of visceral fat pads, adipose size, and adipose angiotensin II levels were analyzed at the end of the study. The results showed that the fructose-fed rats significantly developed hypertension, impaired glucose tolerance, heavier weight and larger adipose size of visceral fat pads, and raised adipose angiotensin II expressions compared with the control rats. High- and low-dose calcitriol reduced modestly systolic blood pressure, increased endothelium-dependent aortic relaxation, ameliorated glucose intolerance, reduced the weight and adipose size of visceral fat pads, and lowered adipose angiotensin II expressions in the fructose-fed rats. However, high-dose calcitriol treatment mildly increased serum ionized calcium levels (1.44 ± 0.05 mmol/L. These results suggest a protective role of calcitriol treatment on endothelial

Impaired vascular sensitivity to nitric oxide in the coronary microvasculature after endotoxaemia

OpenAIRE

Bogle, Richard G; McLean, Peter G; Ahluwalia, Amrita; Vallance, Patrick

2000-01-01

The effects of endotoxaemia on coronary vasodilator responses to bradykinin (BK), sodium nitroprusside (SNP) and nicardipine were investigated in the rat isolated heart perfused at constant flow ex vivo.Dose-dependent reductions in coronary perfusion pressure reaching a maximum of 56±3 and 57±5 mmHg were observed for BK and SNP respectively. The BK response was biphasic, consisting of a rapid dilator response that was insensitive to NGnitro-L-arginine methyl ester (L-NAME, 0.1 mM) and a secon...

Noninvasive Coronary Angiography with 64-Channel Multidetector Computed Tomography in Patients with Acute Coronary Syndrome

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Ulimoen, G. R.; Gjoennaess, E.; Atar, D.; Dahl, T.; Stranden, E.; Sandbaek, G. (Dept. of Radiology, Dept. of Vascular Diagnosis and Research, and Division of Cardiology, Aker Univ. Hospital, Oslo (Norway))

2008-12-15

Background: Advances in computer tomography (CT) imaging technology in recent years have facilitated the possibility of noninvasive coronary angiography. Purpose: To compare the diagnostic accuracy of 64-channel multidetector computed tomography (MDCT) with conventional invasive coronary angiography (ICA) for the detection of significant coronary stenosis in patients with acute coronary syndrome (ACS). Material and Methods: MDCT was performed in 60 patients classified with non-ST-elevation infarction (NSTEMI) or unstable angina and scheduled for ICA within 3 days. The diagnostic accuracy of MDCT was evaluated using quantitative coronary angiography (QCA) as the gold standard. Results: 48 out of 60 patients had interpretable scans by both MDCT and ICA. On a segment-based analysis, 488 out of 665 segments with a diameter of =1.5 mm, as defined by QCA, were interpretable by MDCT. Sensitivity was 78%, specificity 87%, positive predictive value 47%, and negative predictive value 97% in detecting and excluding significant coronary stenosis, as defined with MDCT. On a per patient-based analysis, sensitivity was 89%, specificity 50%, positive predictive value 84%, and negative predictive value 60%. Conclusion: Limited diagnostic accuracy restricts the usefulness of coronary MDCT in patient groups with a high pretest probability of disease, such as in acute coronary syndrome.

Noninvasive Coronary Angiography with 64-Channel Multidetector Computed Tomography in Patients with Acute Coronary Syndrome

International Nuclear Information System (INIS)

Ulimoen, G. R.; Gjoennaess, E.; Atar, D.; Dahl, T.; Stranden, E.; Sandbaek, G.

2008-01-01

Background: Advances in computer tomography (CT) imaging technology in recent years have facilitated the possibility of noninvasive coronary angiography. Purpose: To compare the diagnostic accuracy of 64-channel multidetector computed tomography (MDCT) with conventional invasive coronary angiography (ICA) for the detection of significant coronary stenosis in patients with acute coronary syndrome (ACS). Material and Methods: MDCT was performed in 60 patients classified with non-ST-elevation infarction (NSTEMI) or unstable angina and scheduled for ICA within 3 days. The diagnostic accuracy of MDCT was evaluated using quantitative coronary angiography (QCA) as the gold standard. Results: 48 out of 60 patients had interpretable scans by both MDCT and ICA. On a segment-based analysis, 488 out of 665 segments with a diameter of =1.5 mm, as defined by QCA, were interpretable by MDCT. Sensitivity was 78%, specificity 87%, positive predictive value 47%, and negative predictive value 97% in detecting and excluding significant coronary stenosis, as defined with MDCT. On a per patient-based analysis, sensitivity was 89%, specificity 50%, positive predictive value 84%, and negative predictive value 60%. Conclusion: Limited diagnostic accuracy restricts the usefulness of coronary MDCT in patient groups with a high pretest probability of disease, such as in acute coronary syndrome

Aneurysmal coronary artery disease: An overview

Science.gov (United States)

ElGuindy, Mohamed S.

Aneurysmal coronary artery disease (ACAD) comprises both coronary artery aneurysms (CAA) and coronary artery ectasia (CAE). The reported prevalence of ACAD varies widely from 0.2 to 10%, with male predominance and a predilection for the right coronary artery (RCA). Atherosclerosis is the commonest cause of ACAD in adults, while Kawasaki disease is the commonest cause in children and adolescents, as well as in the Far East. Most patients are asymptomatic, but when symptoms do exist, they are usually related to myocardial ischemia. Coronary angiography is the mainstay of diagnosis, but follow up is best achieved using noninvasive imaging that does not involve exposure to radiation. The optimal management strategy in patients with ACAD remains controversial. Medical therapy is indicated for the vast majority of patients and includes antiplatelets and/or anticoagulants. Covered stents effectively limit further expansion of the affected coronary segments. Surgical ligation, resection, and coronary artery bypass grafting are appropriate for large lesions and for associated obstructive coronary artery disease. PMID:29564347

Nuclear cardiology and coronary surgery

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Eckardt, R.; Andersen, L.I.; Hesse, B.

2008-01-01

Rising age, repeated percutaneous coronary revascularizations, and co-morbidity such as overweight, diabetes, and hypertension, characterize a change over the last 20-30 years in coronary patients referred to coronary artery bypass grafting (CABG). This patient group represents a great part of to...

The influence factors in image quality of multi-slice spiral CT coronary angiography (MSCTA)

International Nuclear Information System (INIS)

Zeng Huiliang; Zhu Xinjin; Liang Jianhao; Zhong Yingze; Chen Xueguang; Ou Weiqian; Wen Haomao; Li Peiwen

2007-01-01

Objective: To evaluate the influence of heart rate on image quality of multi-slice spiral CT coronary angiography(MSCTA) and the optimization of image reconstruction windows. Methods: Retrospectively ECG-gated MSCT coronary angiography were performed in 67 cases. The cases were divided into four groups by heart rate, groupl with heart rate less than 60 beats per minute(bpm), group 2 with heart rate 61-70 bpm, group 3 with heart rate 71-80 bpm and group 4 with heart rate over 81 bpm. The impact of heart rate on image quality of MSCTA and the optimization of image reconstruction windows were evaluated. Results: 4 coronary (RCA,LM,LAD,LCX) segments were analyzed in each patients with regard to image quality. 86.7%(112/128) of the coronary segments were sufficient for analysis in patients with heart rate less than 60 bpm,62.5%(55/88) with 61-70 bpm,40%(8/20) with 71-80 bpm and 12.5%(2/16) with heart rate over 81 bpm, respectively. There were statistically significances between every coronary segments of group 1 and 2, group 3 and 4 (P<0.05). All coronary segments of group 1 were optimally visualized on the image reconstructed at 75% image reconstruction window of' cardiac cycle; 89.5% cases at 75% in group 2; for group 3.55% of coronary artery were best presented at 75% image reconstruction window, 45% of coronary artery at 45%; All coronary segments of group 4 were optimally visualized on the image reconstructed at 45% image reconstruction window. Conclusion: Image quality of MSCT coronary angiography is highly dependent on heart rate. Coronary artery is usually best shown at 75% image reconstruction window of cardiac cycle for those with heart rate less than 70 bpm. 30%-90% image reconstruction should be performed when heart rate is over 71 bpm. (authors)

Comparison of the effects of intraocular irrigating solutions on the corneal endothelium in intraocular lens implantation.

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Matsuda, M; Kinoshita, S; Ohashi, Y; Shimomura, Y; Ohguro, N; Okamoto, H; Omoto, T; Hosotani, H; Yoshida, H

1991-01-01

We conducted a randomised prospective controlled study to determine the effects of a glucose glutathione bicarbonate solution (BSS Plus) and a citrate acetate bicarbonate solution (S-MA2) on the corneal endothelium in patients undergoing extracapsular cataract extraction with posterior chamber lens implantation. One eye of each patient was randomly assigned to receive BSS Plus, and the other eye to receive S-MA2. BSS Plus caused significantly less corneal swelling on the first postoperative day than did S-MA2. There was no difference between the two solutions in their effect on corneal thickness one week and one month postoperatively. Computer assisted morphometric analysis of wide-field specular microscopic photographs demonstrated minimal changes in endothelial morphological characteristics in the eyes irrigated with BSS Plus. By comparison S-MA2, caused a significant loss of endothelial cells and a marked reduction in the figure coefficient. These results indicated that BSS Plus has a clinical advantage over S-MA2 with respect to the corneal endothelium. PMID:1873266

Evaluation of endothelium-dependent myocardial perfusion reserve in healthy smokers; cold pressor test using H215O PET

International Nuclear Information System (INIS)

Hwang, Kyung Hoon; Lee, Dong Soo; Lee, Byeong Il; Lee, Jae Sung; Lee, Ho Young; Chung, June Key; Lee, Myung Chul

2004-01-01

Much evidence suggests long-term cigarette smoking alters coronary vascular endothelial response. In this study, we applied nonnegative matrix factorization (NMF), an unsupervised learning algorithm, to CO-less H 2 15 O-PET to investigate coronary endothelial dysfunction caused by smoking noninvasively. This study enrolled eighteen young male volunteers consisting of 9 smokers (23.8±1.1 yr; 6.6±2.5 pack-years) and 9 nonsmokers (23.8±2.9 yr). They do not have any cardiovascular risk factor or disease history. Myocardial H 2 15 O-PET was performed at rest, during cold (5.deg.C) pressor stimulation and during adenosine infusion. Left ventricular blood pool and myocardium were segmented on dynamic PET data by NMF method. Myocardial blood flow (MBF) was calculated from input and tissue functions by a single compartmental model with correction of partial volume and spillover effects. There were no significant difference in resting MBF between the two groups (Smokers: 1.43 0.41ml/g/min and non-smokers: 1.37±0.41 ml/g/min; p = NS). during cold pressor stimulation, MBF in smokers was significantly lower than that in non-smokers (1.25±0.34 ml/g/min vs 1.59±0.29 ml/g/min ; p = 0.019). The difference in the ratio of cold pressor MBF to resting MBF between the two groups was also significant (p=0.024; 90±24% in smokers and 122±28% in non-smokers.). During adenosine infusion, however, hyperemic MBF did not differ significantly between smokers and non-smokers (5.81±1.99 ml/g/min vs 5.11±1.31 ml/g/min ; p=NS). In smokers, MBF during cold pressor stimulation was significantly lower compared with nonsmokers, reflecting smoking-induced endothelial dysfunction. However, there was no significant difference in MBF during adenosine-induced hyperemia between the two groups

Frequency and importance of radiologically visible coronary scleroses

International Nuclear Information System (INIS)

Hoyer, B.

1981-01-01

The importance of radiologically visible coronary sceleroses for an early diagnosing of coronary heart disease was investigated. In 3 mixed collectives of patients with and without coronary heart diseases who had had a coronary angiography were examined retrospectively for coronary sclerosis (group I: standard films, group II: old X-ray findings, group III: fluoroscopy before beginning coronary angiography). In the retrospective evaluation, the sensitivity to the recognition of coronary heart disease was low. With prospective examination by means of fluoroscopy, coronary calcification could be proven in 37.66% of the patients with coronary diseases (sensitivity); the specificity (no coronary calcification in persons without coronary disease) was 99%. The duration and extent of a calcification do not show a definite influence on the severity of the disease. Several coronary scleroses in one or several vessels mostly indicate a vascular disease. Coronary scleroses are not necessarily located in the same point as coronary stenoses: in 85.5% of the patients with coronary sclerosis of the left truncus, haemodynamically important stenoses were found only in following vascular regions. Considering the high specificity of coronary scleroses in the fluoroscopic picture and the high sensitivity under favourable conditions, this method seems to be suitable as a screening method for early recognition of coronary heart diseases in the asymptomatic stage. A proven coronary sclerosis should in any case be the cause for continuing the search for a coronary heart disease. The radiation exposure during fluoroscopy of coronary sclerosis is low if the adjustment is correct, it takes little time, the patient is not put to discomfort. (orig./MG) [de

Feasibility and diagnostic power of transthoracic coronary Doppler for coronary flow velocity reserve in patients referred for myocardial perfusion imaging

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Nylander Eva

2008-03-01

Full Text Available Abstract Background Myocardial perfusion imaging (MPI, using single photon emission computed tomography (SPECT is a validated method for detecting coronary artery disease. Transthoracic Doppler echocardiography (TTDE of flow at rest and during adenosine provocation has previously been evaluated in selected patient groups. We therefore wanted to compare the diagnostic ability of TTDE in the left anterior descending coronary artery (LAD to that of MPI in an unselected population of patients with chest pain referred for MPI. Our hypothesis was that TTDE with high accuracy would identify healthy individuals and exclude them from the need for further studies, enabling invasive investigations to be reserved for patients with a high probability of disease. Methods Sixty-nine patients, 44 men and 25 women, age 61 ± 10 years (range 35–82, with a clinical suspicion of stress induced myocardial ischemia, were investigated. TTDE was performed at rest and during adenosine stress for myocardial scintigraphy. Results We found that coronary flow velocity reserve (CFVR determined from diastolic measurements separated normal from abnormal MPI findings with statistical significance. TTDE identified coronary artery disease, defined from MPI, as reversible ischemia and/or permanent defect, with a sensitivity of 60% and a specificity of 79%. The positive predictive value was 43% and the negative predictive value was 88%. There was an overlap between groups which could be due to abnormal endothelial function in patients with normal myocardial perfusion having either hypertension or diabetes. Conclusion TTDE is an attractive non-invasive method to evaluate chest pain without the use of isotopes, but the diagnostic power is strongly dependent on the population investigated. Even in our heterogeneous clinical cardiac population, we found that CFVR>2 in the LAD excluded significant coronary artery disease detected by MPI.

THE PLURAL LESION CORONARY AND CYTOKINES DISBALANCE IN PATIENTS WITH CORONARY ATHEROSCLEROSIS

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Martynov AV

2012-12-01

Full Text Available The aim of the study was to examine the levels of the main pro-inflammatory and anti-inflammatory cytokines in patients with ischemic heart disease, and the study of the possible impact of persistent herpes virus infection plural lesion coronary arteries. A total of 57 patients (mean age 49,3 ± 3,7 years IHD s hemodynamically significant stenoses of the coronary vessels. Conducted virological examination, including the definition of hypertension HSV1, HSV2, HHV6, SMV, VZV and VEB immunofluorescent and cytokines ІL-1β, ІL-6 ІL-8, TNF by ELISA in serum. Found increased levels of proinflammatory cytokines ІL-1β, ІL-6 and FNPα of IHD patients who had hemodynamically significant stenoses of coronary vessels. ІL-6 level in patients with 2 or more significant coronary artery lesions exceeded the rate of patients with a damaged coronary artery in 1.67 TNFα, ІL-8 - 1.37 ІL-1β and 1.28 times respectively. In patients with plural coronary vascular damage was the most common combination of CMV, VEB and HHV6. Since CMV was detected in more than 60% of patients with injuries of two spacecraft and nearly 76% from three spacecraft, VEB was detected in 72% and 88%, respectively.

A rare anomaly: Double right coronary artery

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Dursun Çayan Akkoyun

2013-01-01

Full Text Available Coronary artery anomalies are rare anomalies. Theseare usually asymptomatic and are discovered incidentally.Double right coronary artery (RCA is a rare coronaryartery anomaly. Although there is controversy aboutidentification and classification of double RCA, it is oftena benign condition, but it can be complicated by atherosclerosisand can lead to serious conditions such asmyocardial infarction (MI and may be accompanied byother anomalies. In our case, double RCA were detectedin coronary angiography for acute anterior MI, and in thenext session successful percutaneous coronary interventionwas performed.Key words: Coronary anomaly, coronary angiography,coronary stenosis

Proton nuclear magnetic resonance study on the barrier function of pig corneal epithelium and endothelium

International Nuclear Information System (INIS)

Yokoi, Norihiko; Kinoshita, Shigeru; Morimoto, Taketoshi; Yoshizaki, Kazuo.

1995-01-01

Using gadolinium diethylenetriaminepentaacetic acid (Gd-DTPA) as a tracer, the barrier function of the corneal epithelium and endothelium was evaluated by proton nuclear magnetic resonance. Whole pig eyes and cornea excised with scleral rim, which had been incubated in dextran-added Gd-DTPA solution, were subjected to T 1 relaxation measurement and magnetic resonance imaging (MRI). After incubation, the T 1 relaxation rate (1/T 1 ) of the excised cornea increased to a steady value, whereas that of the cornea from the whole eye increased only slightly. These results indicated that the increase in the T 1 relaxation rate of the excised cornea was attributable to Gd-DTPA penetration from the corneal endothelium and that the corneal epithelium exhibited a strong barrier function against Gd-DTPA entry. The MRI study also confirmed the strong barrier, enhanced signals being detected within the aqueous fluid in the T 1 -weighted image only when the corneal epithelium was abraded. Since Gd-DTPA scarcely penetrates the intact corneal epithelium, Gd-DTPA-enhanced MRI shows potential as a quantitative tracer in evaluating epithelial barrier disruption. (author)

Alcohol Intake and Risk of Coronary Heart Disease in Younger, Middle-Aged, and Older Adults

DEFF Research Database (Denmark)

Hvidtfeldt, Ulla A; Tolstrup, Janne S; Jakobsen, Marianne U

2010-01-01

prospective studies from North America and Europe including 192 067 women and 74 919 men free of cardiovascular diseases, diabetes, and cancers at baseline, average daily alcohol intake was assessed at baseline with a food frequency or diet history questionnaire. An inverse association between alcohol......BACKGROUND: -Light to moderate alcohol consumption is associated with a reduced risk of coronary heart disease. This protective effect of alcohol, however, may be confined to middle-aged or older individuals. Coronary heart disease incidence is low in men ... of age; for this reason, study cohorts rarely have the power to investigate the effects of alcohol on coronary heart disease risk in younger adults. This study examined whether the beneficial effect of alcohol on coronary heart disease depends on age. Methods and Results-In this pooled analysis of 8...

[The effects of intraocular irrigating solutions on the human corneal endothelium (author's transl)].

Science.gov (United States)

Weekers, J F; Dethinne, M

1978-11-01

Human corneas from enucleated eyes get thicker during perfusion with B.S.S. On the contrary, their thickness decreases when perfused with T.C. Earle solution. Addition of reduced glutathion and adenosine does not change the results obtained with T.C. Earle. Histological study of the endothelium after a 24 hours perfusion demonstrates a better conservation of the cells with T.C. Earle and T.C. Earle glutathion--adenosine than with B.S.S.

Percutaneous coronary angioplasty versus coronary artery bypass grafting in treatment of unprotected left main stenosis (NOBLE)

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Mäkikallio, Timo; Holm, Niels R; Lindsay, Mitchell

2016-01-01

Background Coronary artery bypass grafting (CABG) is the standard treatment for revascularisation in patients with left main coronary artery disease, but use of percutaneous coronary intervention (PCI) for this indication is increasing. We aimed to compare PCI and CABG for treatment of left main...... coronary artery disease. Methods In this prospective, randomised, open-label, non-inferiority trial, patients with left main coronary artery disease were enrolled in 36 centres in northern Europe and randomised 1: 1 to treatment with PCI or CABG. Eligible patients had stable angina pectoris, unstable......, and 5% versus 2% (2 . 25, 0 . 93-5 . 48, p= 0 . 073) for stroke. Interpretation The findings of this study suggest that CABG might be better than PCI for treatment of left main stem coronary artery disease....

Single left coronary ostium and an anomalous prepulmonic right coronary artery in 2 dogs with congenital pulmonary valve stenosis.

Science.gov (United States)

Visser, Lance C; Scansen, Brian A; Schober, Karsten E

2013-06-01

A coronary artery anomaly characterized by the presence of a single left coronary ostium with absence of the right coronary ostium and an anomalous prepulmonic right coronary artery course was observed in two dogs with concurrent congenital pulmonary valve stenosis. This unique coronary artery anatomy is similar to the previously described single right coronary ostium with anomalous prepulmonic left coronary artery, the so-called type R2A anomaly, in that an anomalous coronary artery encircles the pulmonary valve annulus. Both dogs of this report, a boxer and an English bulldog, were of breeds known to be at risk for the type R2A anomaly. As such, veterinarians should be aware that the echocardiographic presence of a left coronary ostium in a dog with pulmonary valve stenosis does not exclude the possibility of a prepulmonic coronary artery anomaly that may enhance the risk of complications during balloon pulmonary valvuloplasty. A descriptive naming convention for coronary artery anomalies in dogs is also presented, which may be preferable to the older coding classification scheme. Copyright © 2013 Elsevier B.V. All rights reserved.

Coronary arterio-venous fistula associated acute coronary syndrome: A case-report and review of literature

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V.H. Contreras-Gutiérrez

2017-01-01

Full Text Available A 56-year-old woman with no medical history presented to the emergency department complaining of oppressive chest pain of three hours of duration triggered by walking. An electrocardiogram (ECG performed at hospital admission showed ST-segment depression and T-wave inversion in left precordial and inferior leads. Serum troponin I levels were above the normal values. Non ST-segment elevation acute coronary syndrome (NSTEACS was diagnosed and an invasive approach with a percutaneous coronary intervention was performed. No obstructive coronary lesions were observed. However a tortuous coronary fistula emerging from the left-anterior descending coronary artery to the pulmonary artery was observed. Coronary arterio-venous fistulas are present in 0.002% of the general population and in 0.25% of patients undergoing cardiac catheterization for any cause. Most of them are asymptomatic. Ischemic symptoms may develop but are infrequent in patients with no atherosclerotic disease.

Persistence of recruitable coronary collaterals in the absence of coronary vasospasm in a patient with variant angina

International Nuclear Information System (INIS)

Yamashita, Kazuhito; Takeuchi, Masaaki; Nakashima, Yasuhide

1998-01-01

Recruitable coronary collaterals may appear when spasm suddenly occludes the coronary artery. We report a patient with variant angina who had visible collateral vessels on a control coronary angiogram, despite the presence of normally appearing coronary arteries. These collaterals disappeared after intracoronary administration of nitroglycerin. These findings suggest that recruitable collateral vessels can remain patent long after spontaneous attacks of angina have resolved, and become visible when there is a pressure difference between two small coronary arteries.

Persistence of Recruitable Coronary Collaterals in the Absence of Coronary Vasospasm in a Patient with Variant Angina

International Nuclear Information System (INIS)

Yamashita, Kazuhito; Takeuchi, Masaaki; Nakashima, Yasuhide

1998-01-01

Recruitable coronary collaterals may appear when spasm suddenly occludes the coronary artery. We report a patient with variant angina who had visible collateral vessels on a control coronary angiogram, despite the presence of normally appearing coronary arteries. These collaterals disappeared after intracoronary administration of nitroglycerin. These findings suggest that recruitable collateral vessels can remain patent long after spontaneous attacks of angina have resolved, and become visible when there is a pressure difference between two small coronary arteries

Evaluation of hemodynamic significance of coronary fistulae. Diagnostic integration between coronary angiography and stress/rest myocardial scintigraphy

International Nuclear Information System (INIS)

Rubini, G.; Sebastiani, M.

2000-01-01

It is here reported on the importance of the integration of data obtained from digital coronary angiography and stress/rest 99m Tc sestamibi myocardial perfusion single photon emission tomography in evaluationing the hemodynamic significance of coronary arteriovenous fistulae. Coronary fistulae were detected with coronary angiography in 9 patients. All patients underwent clinical examination, trans thoracic echocardiography, stress electrocardiogram and stress/rest 99m Tc sestamibi myocardial perfusion single photon emission tomography. Stress/rest 99m Tc sestamibi myocardial perfusion single photon tomography and stress electrocardiogram showed stress-induced myocardial ischemia in 2 patients. The first patient with familial predisposition and risk factors for ischemic heart disease presented a mesocardic heart murmur on clinical examination. At stress ECG (125 Watt, 153 b/m max frequency 93%, arterial pressure 230 mmHg, max frequency pressure product 35200) ischemic alterations were recorded at the first minute of the second stage of the Bruce protocol. Coronary angiography detected a circumflex artery fistula in the coronary sinus. Stress/rest 99m Tc sestamibi myocardial perfusion single photon emission tomography for the evaluation of stress/rest perfusion detected a reversible perfusion defect of the proximal portion of the posterolateral and lateral walls, thus confirming the hemodynamic importance of the flow through the fistula during stress cycloergometric testing. In the second patient familial predisposition to ischemic heart disease and previous inferior wall myocardial infarction and non-significant stress ECG, coronary angiography identified a seclusive stenosis of the right coronary artery and anomaly between the anterior interventricular artery and the left pulmonary artery. The presence of the contrast medium in the left pulmonary artery identified a flow from the left ventricle to the left pulmonary artery. Good angiographic results were obtained

Spontaneous coronary artery dissection causing acute coronary syndrome in a young patient without risk factors

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Parag Chevli

2014-09-01

Full Text Available Spontaneous coronary artery dissection (SCAD is a rare cause of acute myocardial infarction that is more common in younger patients (under age 50 and in women. Although the etiology is not known, some predisposing conditions to SCAD are well known and include Marfan syndrome, pregnancy and peripartum state, drug abuse, and some anatomical abnormalities of the coronary arteries such as aneurysms and severe kinking. We describe a case of SCAD in a young woman who presented with sudden onset of chest pain and was admitted for the treatment of acute coronary syndrome. The coronary angiography showed dissection of the left anterior descending artery. The patient underwent successful percutaneous transluminal coronary angioplasty and stent placement.

Morphometry of the coronary ostia and the structure of coronary arteries in the shorthair domestic cat

Science.gov (United States)

Barszcz, Karolina; Kupczyńska, Marta; Klećkowska-Nawrot, Joanna; Janeczek, Maciej; Goździewska-Harłajczuk, Karolina; Dzierzęcka, Małgorzata; Janczyk, Paweł

2017-01-01

The aim of this study was to measure the area of the coronary ostia, assess their localization in the coronary sinuses and to determine the morphology of the stem of the left and right coronary arteries in the domestic shorthair cat. The study was conducted on 100 hearts of domestic shorthair cats of both sexes, aged 2–18 years, with an average body weight of 4.05 kg. A morphometric analysis of the coronary ostia was carried out on 52 hearts. The remaining 48 hearts were injected with a casting material in order to carry out a morphological assessment of the left and right coronary arteries. In all the studied animals, the surface of the left coronary artery ostium was larger than the surface of the right coronary artery ostium. There were four types of the left main coronary artery: type I (23 animals, 49%)–double-branched left main stem (giving off the left circumflex branch and the interventricular paraconal branch, which in turn gave off the septal branch), type II (12 animals, 26%)–double-branched left main stem (giving off the left circumflex branch and the interventricular paraconal branch without the septal branch), type III (11 animals, 23%)–triple-branched left main stem (giving off the left circumflex branch, interventricular branch and the septal branch, type IV (1 animal, 2%)–double-branched left main stem (giving off the interventricular paraconal branch and the left circumflex branch, which in turn gave off the septal branch). The left coronary artery ostium is greater than the right one. There is considerable diversity in the branches of proximal segment of the left coronary artery, while the right coronary artery is more conservative. These results can be useful in defining the optimal strategies in the endovascular procedures involving the coronary arteries or the aortic valve in the domestic shorthair cat. PMID:29020103

Lack of a relationship between serum ferritin levels and coronary atherosclerosis evaluated by coronary arteriography

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W.C. Manfroi

1999-03-01

Full Text Available Many clinical and epidemiological studies have demonstrated the relationship between serum ferritin and ischemic heart disease. In the present study we evaluated the relationship between coronary heart disease (CHD and serum ferritin levels in patients submitted to coronary arteriography. We evaluated 307 patients (210 (68.7% males; median age: 60 years who were submitted to coronary angiography, measurement of serum ferritin and identification of clinical events of ischemic heart disease. Serum ferritin is reported as quartiles. Ninety-six patients (31.27% had normal coronary angiography (group 1 and 211 (68.73% had coronary heart disease (group 2. Of the patients with CHD, 61 (28.9% had serum ferritin levels higher than 194 ng/ml (4th quartile, as opposed to only 14 (14.58% of those without CHD (P = 0.0067. In the 2nd quartile, 39 patients (18.48% had CHD, while 35 patients (36.46% had normal coronary arteries (P = 0.00064. Multivariate analysis of the data showed that the difference between groups was not statistically significant (P = 0.33. We conclude that there is no independent relationship between coronary heart disease and increased levels of serum ferritin.

High-resolution coronary MR angiography for evaluation of patients with anomalous coronary arteries: visualization of the intramural segment

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Biko, David M. [UCSF Benioff Children' s Hospital Oakland, Department of Diagnostic Imaging, Oakland, CA (United States); The Children' s Hospital of Philadelphia, Department of Radiology, Philadelphia, PA (United States); Chung, Claudia; Chung, Taylor [UCSF Benioff Children' s Hospital Oakland, Department of Diagnostic Imaging, Oakland, CA (United States); Hitt, David M. [Philips Healthcare, Cleveland, OH (United States); Kurio, Gregory [UCSF Benioff Children' s Hospital Oakland, Department of Cardiology, Oakland, CA (United States); Reinhartz, Olaf [UCSF Benioff Children' s Hospital Oakland, Department of Cardiac Surgery, Oakland, CA (United States)

2015-08-15

Anomalous origin of the coronary artery from the contralateral coronary sinus is a rare coronary anomaly associated with sudden death. The inter-arterial course is most closely associated with sudden death, but it has been suggested that the presence of an intramural segment of a right anomalous coronary is associated with more symptoms and therefore may be an important criterion for intervention in these patients. To demonstrate that MR angiography can accurately determine the presence or absence of an intramural segment in an anomalous coronary artery. All studies of children who underwent MR angiography for the evaluation of an anomalous coronary artery were retrospectively reviewed by two pediatric radiologists in consensus. Criteria for an intramural anomalous coronary artery were the presence of a small or slit-like ostium and the relative smaller size of the proximal intramural portion of the coronary artery in relation to the more distal epicardial coronary artery. The anomalous coronary artery was classified as not intramural if these two findings were absent. These findings were correlated with operative reports confirming the presence or absence of an intramural segment. Twelve patients (86%) met MR angiography criteria for the presence of an intramural course. Only 2 patients (14%) met MR angiography criteria for a non-intramural course. When correlating with intraoperative findings, MR angiography was successful in distinguishing between intramural and non-intramural anomalous coronary arteries in all cases (P = 0.01). MR angiography may be able to reliably identify the intramural segment of an anomalous coronary artery in older children using the imaging criteria of a small or slit-like ostium and relative decrease in size of the proximal portion of the anomalous coronary artery compared to the distal portion of the anomalous coronary artery. Determining the presence of the intramural segment may help with surgical planning and may be an important

The calmodulin inhibitor CGS 9343B inhibits voltage-dependent K{sup +} channels in rabbit coronary arterial smooth muscle cells

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Li, Hongliang; Hong, Da Hye; Kim, Han Sol; Kim, Hye Won [Institute of Medical Sciences, Department of Physiology, Kangwon National University School of Medicine, Chuncheon, 200-701 (Korea, Republic of); Jung, Won-Kyo [Department of Biomedical Engineering, Center for Marine-Integrated Biomedical Technology (BK21 Plus), Pukyong National University, Busan 608-737 (Korea, Republic of); Na, Sung Hun [Institute of Medical Sciences, Department of Obstetrics and Gynecology, Kangwon National University Hospital, School of Medicine, Kangwon National University, Chuncheon, 200-701 (Korea, Republic of); Jung, In Duk; Park, Yeong-Min [Department of Immunology, Lab of Dendritic Cell Differentiation and Regulation, College of Medicine, Konkuk University, Chungju 380-701 (Korea, Republic of); Choi, Il-Whan, E-mail: cihima@inje.ac.kr [Department of Microbiology, Inje University College of Medicine, Busan, 614-735 (Korea, Republic of); Park, Won Sun, E-mail: parkws@kangwon.ac.kr [Institute of Medical Sciences, Department of Physiology, Kangwon National University School of Medicine, Chuncheon, 200-701 (Korea, Republic of)

2015-06-15

We investigated the effects of the calmodulin inhibitor CGS 9343B on voltage-dependent K{sup +} (Kv) channels using whole-cell patch clamp technique in freshly isolated rabbit coronary arterial smooth muscle cells. CGS 9343B inhibited Kv currents in a concentration-dependent manner, with a half-maximal inhibitory concentration (IC{sub 50}) value of 0.81 μM. The decay rate of Kv channel inactivation was accelerated by CGS 9343B. The rate constants of association and dissociation for CGS 9343B were 2.77 ± 0.04 μM{sup −1} s{sup −1} and 2.55 ± 1.50 s{sup −1}, respectively. CGS 9343B did not affect the steady-state activation curve, but shifted the inactivation curve toward to a more negative potential. Train pulses (1 or 2 Hz) application progressively increased the CGS 9343B-induced Kv channel inhibition. In addition, the inactivation recovery time constant was increased in the presence of CGS 9343B, suggesting that CGS 9343B-induced inhibition of Kv channel was use-dependent. Another calmodulin inhibitor, W-13, did not affect Kv currents, and did not change the inhibitory effect of CGS 9343B on Kv current. Our results demonstrated that CGS 9343B inhibited Kv currents in a state-, time-, and use-dependent manner, independent of calmodulin inhibition. - Highlights: • We investigated the effects of CGS 9394B on Kv channels. • CGS 9394B inhibited Kv current in a state-, time-, and use-dependent manner. • Caution is required when using CGS 9394B in vascular function studies.

Target vessel detection by epicardial ultrasound in off-pump coronary bypass surgery.

Science.gov (United States)

Hayakawa, Masato; Asai, Tohru; Kinoshita, Takeshi; Suzuki, Tomoaki; Shiraishi, Shoichiro

2013-01-01

The detection of embedded coronary arteries is difficult especially in off-pump coronary bypass surgery. From June 2010, we introduced high-frequency epicardial ultrasound (ECUS) to assess and evaluate embedded arteries during off-pump coronary bypass surgery. Between June 2010 and June 2011, a total of 89 consecutive patients underwent isolated coronary bypass surgery at our institution. The patients consisted of 72 men and 17 women with a mean age of 67.9 years. We routinely use the VeriQC system (MediStim, Oslo, Norway) to detect the target vessels in the operation. The patients were assigned to one of two groups, depending on whether ECUS was used in the operation (n = 10, ECUS group) or not (n = 79, non-ECUS group). We analyzed the impact of introducing the ECUS in terms of operative outcome. All patients underwent revascularization using the off-pump technique without emergent conversion to cardiopulmonary bypass during surgery. The total number of distal anastomoses was 299, and 12 target vessels could not be identified either visually or on palpation. Thus, the frequency of the embedded coronary arteries was 4.01% (12/299 cases). The preoperative profiles of the two groups were not significantly different. Operation time was significantly longer in the ECUS group (P = 0.02). There were no significant differences in postoperative outcome between the two groups. In the present study, in which the target coronary arteries could not be detected either visually or on palpation in 12 (4.01%) of 299 cases, the use of high-frequency ECUS allowed all patients to undergo off-pump coronary bypass surgery without conversion to cardiopulmonary bypass during the operation. High-frequency ECUS is therefore useful in off-pump coronary bypass surgery.

Influence of type of aortic valve prosthesis on coronary blood flow velocity.

Science.gov (United States)

Jelenc, Matija; Juvan, Katja Ažman; Medvešček, Nadja Tatjana Ružič; Geršak, Borut

2013-02-01

Severe aortic valve stenosis is associated with high resting and reduced hyperemic coronary blood flow. Coronary blood flow increases after aortic valve replacement (AVR); however, the increase depends on the type of prosthesis used. The present study investigates the influence of type of aortic valve prosthesis on coronary blood flow velocity. The blood flow velocity in the left anterior descending coronary artery (LAD) and the right coronary artery (RCA) was measured intraoperatively before and after AVR with a stentless bioprosthesis (Sorin Freedom Solo; n = 11) or a bileaflet mechanical prosthesis (St. Jude Medical Regent; n = 11). Measurements were made with an X-Plore epicardial Doppler probe (Medistim, Oslo, Norway) following induction of hyperemia with an adenosine infusion. Preoperative and postoperative echocardiography evaluations were used to assess valvular and ventricular function. Velocity time integrals (VTI) were measured from the Doppler signals and used to calculate the proportion of systolic VTI (SF), diastolic VTI (DF), and normalized systolic coronary blood flow velocities (NSF) and normalized diastolic coronary blood flow velocities (NDF). The systolic proportion of the LAD VTI increased after AVR with the St. Jude Medical Regent prosthesis, which produced higher LAD SF and NSF values than the Sorin Freedom Solo prosthesis (SF, 0.41 ± 0.09 versus 0.29 ± 0.13 [P = .04]; NSF, 0.88 ± 0.24 versus 0.55 ± 0.17 [P = .01]). No significant changes in the LAD velocity profile were noted after valve replacement with the Sorin Freedom Solo, despite a significant reduction in transvalvular gradient and an increase in the effective orifice area. AVR had no effect on the RCA flow velocity profile. The coronary flow velocity profile in the LAD was significantly influenced by the type of aortic valve prosthesis used. The differences in the LAD velocity profile probably reflect differences in valve design and the systolic transvalvular flow pattern.

Extracellular Calcium-Dependent Modulation of Endothelium Relaxation in Rat Mesenteric Small Artery

DEFF Research Database (Denmark)

Hangaard, Lise; Jessen, Peter B; Kamaev, Dmitrii

2015-01-01

The nature of NO- and COX-independent endothelial hyperpolarization (EDH) is not fully understood but activation of small- and intermittent-conductance Ca(2+)-activated K(+) channels (SKCa and IKCa) is important. Previous studies have suggested that the significance of IKCa depends on [Ca(2+)]out...

Outcomes of coronary artery bypass grafting versus percutaneous coronary intervention with drug-eluting stents for patients with multivessel coronary artery disease.

Science.gov (United States)

Javaid, Aamir; Steinberg, Daniel H; Buch, Ashesh N; Corso, Paul J; Boyce, Steven W; Pinto Slottow, Tina L; Roy, Probal K; Hill, Peter; Okabe, Teruo; Torguson, Rebecca; Smith, Kimberly A; Xue, Zhenyi; Gevorkian, Natalie; Suddath, William O; Kent, Kenneth M; Satler, Lowell F; Pichard, Augusto D; Waksman, Ron

2007-09-11

Advances in coronary artery bypass grafting (CABG) surgery and percutaneous coronary intervention (PCI) with drug-eluting stents have dramatically improved results of these procedures. The optimal treatment for patients with multivessel coronary artery disease is uncertain given the lack of prospective, randomized data reflecting current practice. This study represents a "real-world" evaluation of current technology in the treatment of multivessel coronary artery disease. A total of 1680 patients undergoing revascularization for multivessel coronary artery disease were identified. Of these, 1080 patients were treated for 2-vessel disease (196 CABG and 884 PCI) and 600 for 3-vessel disease (505 CABG and 95 PCI). One-year mortality, cerebrovascular events, Q-wave myocardial infarction, target vessel failure, and composite major adverse cardiovascular and cerebrovascular events were compared between the CABG and PCI cohorts. Outcomes were adjusted for baseline covariates and reported as hazard ratios. The unadjusted major adverse cardiovascular and cerebrovascular event rate was reduced with CABG for patients with 2-vessel disease (9.7% CABG versus 21.2% PCI; P<0.001) and 3-vessel disease (10.8% CABG versus 28.4% PCI; P<0.001). Adjusted outcomes showed increased major adverse cardiovascular and cerebrovascular event with PCI for patients with 2-vessel (hazard ratio 2.29; 95% CI 1.39 to 3.76; P=0.01) and 3-vessel disease (hazard ratio 2.90; 95% CI 1.76 to 4.78; P<0.001). Adjusted outcomes for the nondiabetic subpopulation demonstrated equivalent major adverse cardiovascular and cerebrovascular event with PCI for 2-vessel (hazard ratio 1.77; 95% CI 0.96 to 3.25; P=0.07) and 3-vessel disease (hazard ratio 1.70; 95% CI 0.77 to 3.61; P=0.19). Compared with PCI with drug-eluting stents, CABG resulted in improved major adverse cardiovascular and cerebrovascular event in patients with 2- and 3-vessel coronary artery disease, primarily in those with underlying diabetes

Phototoxic effects of 8-methoxypsoralen on rabbit corneal endothelium

Energy Technology Data Exchange (ETDEWEB)

Menon, I.A.; Basu, P.K.; Hasany, S.M.; Persad, S.D. (Univ. of Toronto, Ontario (Canada))

1989-01-01

The phototoxic effects of 8-methoxypsoralen (8-MOP) were investigated using the rabbit corneal endothelium in organ culture. The corneas were divided into four groups: (a) irradiated with a mercury vapor lamp (emitting UVA and visible radiation) in the presence of 8-MOP (experimental), (b) irradiated without 8-MOP (control A), (c) incubated with 8-MOP (control B) and (d) incubated without 8-MOP (control C). Specular and light microscopic examination showed that the experimental corneas had greater cellular damage compared to the control corneas. The effects of 8-MOP were restricted to certain localized areas of the cornea. However there was no significant difference in the amounts of 51Cr released from the labelled experimental and control corneas. These results show phototoxic damage of the corneal endothelial cells.

Experiment list: DRX014702 [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available || tissue_type=the endothelium of blood vessels || ihec ref=JTK015 || cell type abbreviation=HCAEC || cell ontology...=endothelial cell of coronary artery || cell ontology uri=http://purl.obolibrary.org/obo/CL_2000018 |

Prognosis of non-significant coronary atherosclerotic disease detected by coronary artery tomography

Energy Technology Data Exchange (ETDEWEB)

Barros, Marcio Vinicius Lins; Siqueira, Bruna Pinto; Guimaraes, Carolina Camargos Braichi; Cruz, David Filipe Silva; Guimaraes, Leiziane Assuncao Alves; Lima, Maicom Marcio Perigolo, E-mail: marciovlbarros@gmail.com [Faculdade de Saude e Ecologia Humana, Vespasiano, MG (Brazil); Nunes, Maria do Carmo Pereira [Universidade de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Faculdade de Medicina; Siqueira, Maria Helena Albernaz [Hospital Materdei, Belo Horizonte, MG (Brazil)

2015-07-15

Introduction: Although studies have shown high diagnostic accuracy of coronary tomography (CT) in detecting coronary artery disease (CAD), data on the prognostic value of this method in patients with no significant coronary obstruction are limited. Objective: To evaluate the value of CT in predicting adverse events in patients with suspected CAD and no significant coronary obstruction. Methods: We prospectively evaluated 440 patients between January 2008 and July 2013 by MDCT, diagnosed with no significant obstruction or no atherosclerotic coronary obstruction with an average follow-up of 33 months. The outcomes evaluated were: cardiac death, myocardial infarction, unstable angina associated with hospitalization or coronary artery bypass grafting. Results: Of the 440 patients studied, 295 (67%) were men with mean age 55.9 ± 12.0 years. Non-significant obstruction was found in 152 (35%) of the patients and there were 49 (11%) outcomes. In the multivariate analysis using the Cox regression model, the predictors of clinical outcomes were non-significant obstruction on CT (hazard ratio 3.51; 95% CI 1.73 - 7.8; p <0.01), age and hypertension. Non-significant obstruction on CT was associated with adverse clinical outcomes and survival analysis showed a significant difference (log-rank 24.6; p <0.01) in predicting these outcomes. Conclusion: The detection of non-significant atherosclerotic obstruction by CT was associated with the presence of adverse events in patients with suspected CAD, which may prove useful in the risk stratification of these patients. (author)

Anatomical studies of the coronary system in elasmobranchs: II. Coronary arteries in hexanchoid, squaloid, and carcharhinoid sharks.

Science.gov (United States)

De Andrés, A V; Muñoz-Chápuli, R; Sans-Coma, V; García-Garrido, L

1992-07-01

Coronary artery anatomy was studied in 16 shark species belonging to 9 families of the orders Hexanchiformes, Squaliformes, and Carcharhiniformes. The study included 101 specimens and used an injection-corrosion technique that obtained internal casts of the main trunks and coronary arterial branches. The results showed 2 main patterns of coronary arterial arrangement: the dorsoventral coronary trunk pattern, shared by lamnoid and advanced carcharhinoid sharks, and the lateral coronary trunk pattern, shown by hexanchoid and squaloid sharks. Scyliorhinus and Galeus had intermediate arrangements of their vessels.

EDRF [endothelium-derived relaxing factor]-release and Ca++-channel blockage by Magnolol, an antiplatelet agent isolated from Chinese herb Magnolia officinalis, in rat thoracic aorta

International Nuclear Information System (INIS)

Teng, Cheming; Yu, Sheumeei; Chen, Chienchih; Huang, Yulin; Huang, Turfu

1990-01-01

Magnolol is an antiplatelet agent isolated from Chinese herb Magnolia officinalis. It inhibited norepinephrine-induced phasic and tonic contractions in rat thoracic aorta. At the plateau of the NE-induced tonic contraction, addition of magnolol caused two phases (fast and slow) of relaxation. These two relaxations were concentration-dependent, and were not inhibited by indomethacin. The fast relaxation was completely antagonized by hemoglobin and methylene blue, and disappeared in de-endothelialized aorta while the slow relaxation was not affected by the above treatments. Magnolol also inhibited high potassium-induced, calcium-dependent contraction of rat aorta in a concentration-dependent manner. 45 Ca ++ influx induced by high potassium or NE was markedly inhibited by magnolol. Cyclic GMP, but not PGI 2 , was increased by magnolol in intact, but not in de-endothelialized aorta. It is concluded that magnolol relaxed vascular smooth muscle by releasing endothelium-derived relaxing factor (EDRF) and by inhibiting calcium influx through voltage-gated calcium channels

Coronary 64-slice CT angiography predicts outcome in patients with known or suspected coronary artery disease

Energy Technology Data Exchange (ETDEWEB)

Gaemperli, Oliver; Valenta, Ines; Schepis, Tiziano [University Hospital Zurich NUK C 32, Cardiovascular Center, Zurich (Switzerland); Husmann, Lars; Scheffel, Hans; Desbiolles, Lotus; Leschka, Sebastian; Alkadhi, Hatem [University Hospital Zurich, Institute of Diagnostic Radiology, Zurich (Switzerland); Kaufmann, Philipp A. [University Hospital Zurich NUK C 32, Cardiovascular Center, Zurich (Switzerland); University of Zurich, Zurich Center for Integrative Human Physiology (ZIHP), Zurich (Switzerland)

2008-06-15

The aim of this study was to assess the prognostic value of 64-slice CT angiography (CTA) in patients with known or suspected coronary artery disease (CAD). Sixty-four-slice coronary CTA was performed in 220 patients [mean age 63 {+-} 11 years, 77 (35%) female] with known or suspected CAD. CTA images were analyzed with regard to the presence and number of coronary lesions. Patients were followed-up for the occurrence of the following clinical endpoints: death, nonfatal myocardial infarction, unstable angina, and coronary revascularization. During a mean follow-up of 14 {+-} 4 months, 59 patients (27%) reached at least one of the predefined clinical endpoints. Patients with abnormal coronary arteries on CTA (i.e., presence of coronary plaques) had a 1st-year event rate of 34%, whereas in patients with normal coronary arteries no events occurred (event rate, 0%, p < 0.001). Similarly, obstructive lesions ({>=}50% luminal narrowing) on CTA were associated with a high first-year event rate (59%) compared to patients without stenoses (3%, p < 0.001). The presence of obstructive lesions was a significant independent predictor of an adverse cardiac outcome. Sixty-four-slice CTA predicts cardiac events in patients with known or suspected CAD. Conversely, patients with normal coronary arteries on CTA have an excellent mid-term prognosis. (orig.)

Appropriate control time constant in relation to characteristics of the baroreflex vascular system in 1/R control of the total artificial heart.

Science.gov (United States)

Mizuta, Sora; Saito, Itsuro; Isoyama, Takashi; Hara, Shintaro; Yurimoto, Terumi; Li, Xinyang; Murakami, Haruka; Ono, Toshiya; Mabuchi, Kunihiko; Abe, Yusuke

2017-09-01

1/R control is a physiological control method of the total artificial heart (TAH) with which long-term survival was obtained with animal experiments. However, 1/R control occasionally diverged in the undulation pump TAH (UPTAH) animal experiment. To improve the control stability of the 1/R control, appropriate control time constant in relation to characteristics of the baroreflex vascular system was investigated with frequency analysis and numerical simulation. In the frequency analysis, data of five goats in which the UPTAH was implanted were analyzed with first Fourier transform technique to examine the vasomotion frequency. The numerical simulation was carried out repeatedly changing baroreflex parameters and control time constant using the elements-expanded Windkessel model. Results of the frequency analysis showed that the 1/R control tended to diverge when very low frequency band that was an indication of the vasomotion frequency was relative high. In numerical simulation, divergence of the 1/R control could be reproduced and the boundary curves between the divergence and convergence of the 1/R control varied depending on the control time constant. These results suggested that the 1/R control tended to be unstable when the TAH recipient had high reflex speed in the baroreflex vascular system. Therefore, the control time constant should be adjusted appropriately with the individual vasomotion frequency.

Optical coherence tomography following percutaneous coronary intervention with Excimer laser coronary atherectomy

Energy Technology Data Exchange (ETDEWEB)

Rawlins, John, E-mail: john.rawlins@doctors.net.uk; Talwar, Suneel; Green, Mark; O’Kane, Peter

2014-01-15

The indications for Excimer laser coronary atherectomy (ELCA) have been refined in modern interventional practice. With the expanding role for optical coherence tomography (OCT) providing high-resolution intra-coronary imaging, this article examines the appearance of the coronary lumen after ELCA. Each indication for ELCA is discussed and illustrated with a clinical case, followed by detailed analysis of the OCT imaging pre and post ELCA. The aim of the article is to provide information to interventional cardiologists to facilitate decision making during PCI, when ELCA has been used as part of the interventional strategy.

Coronary Microvascular Function and Cardiovascular Risk Factors in Women With Angina Pectoris and No Obstructive Coronary Artery Disease

DEFF Research Database (Denmark)

Mygind, Naja Dam; Michelsen, Marie Mide; Peña, Adam

2016-01-01

BACKGROUND: The majority of women with angina-like chest pain have no obstructive coronary artery disease when evaluated with coronary angiography. Coronary microvascular dysfunction is a possible explanation and associated with a poor prognosis. This study evaluated the prevalence of coronary...... microvascular dysfunction and the association with symptoms, cardiovascular risk factors, psychosocial factors, and results from diagnostic stress testing. METHODS AND RESULTS: After screening 3568 women, 963 women with angina-like chest pain and a diagnostic coronary angiogram without significant coronary.......01), hypertension (P=0.02), current smoking (Ppain characteristics or results from diagnostic stress testing...

Prevalence of Congenital Coronary Artery Anomalies and Variants in 2697 Consecutive Patients Using 64-Detector Row Coronary CTAngiography

International Nuclear Information System (INIS)

Shabestari, Abbas Arjmand; Akhlaghpoor, Shahram; Tayebivaljozi, Reza; Fattahi Masrour, Farzaneh

2012-01-01

Coronary artery anomalies are not common, but could be very serious. This study determines the frequency of coronary anomalies and normal variants by multi-detector-row computed tomography (MDCT). The results of cardiac MDCT study in 2697 consecutive patients were analyzed retrospectively. Acquisition was performed by a 64-detector row CT machine. Imaging results were assessed by experienced radiologists. Myocardial bridging was by far the most frequent coronary variant (n = 576, 21.3%). Eighty-three subjects (3.1%) showed other coronary anomalies and variants. Anomalies of origination and course of the left main coronary artery (LMCA) were detected in 1.09% of the subjects. The frequency of these anomalies in the right coronary artery (RCA), left circumflex artery (LCx), left anterior descending artery (LAD), posterior descending artery (PDA) and obtuse marginal (OM) artery were 1.24%, 0.33%, 0.1%, 0.07% and 0.03%, respectively. The single coronary pattern was seen in 0.18% and coronary fistulas in 0.07%. Based on the fact that coronary CT-angiography using MDCT can display different coronary anomalies, this study shows similar results to other reports on the subject. Future advances in the performance of CT machines will further improve the quality of CT-based cardiac imaging

[Binding studies with Ulex europaeus agglutinin I (UEA-I) of the vascular endothelium of the synovial membrane].

Science.gov (United States)

Zschäbitz, A; Stofft, E

1988-01-01

The lectin binding sites of the synovium of patients with rheumatoid arthritis and osteoarthritis were investigated. It was shown that Ulex europaeus agglutinin is a constant marker of the vascular endothelium and is not induced during the course of inflammatory process in rheumatoid arthritis.

Sarpogrelate hydrochloride, a selective 5-hydroxytryptamine(2A) antagonist, augments autologous bone marrow mononuclear cell implantation-induced improvement in endothelium-dependent vasodilation in patients with critical limb ischemia.

Science.gov (United States)

Higashi, Yukihito; Miyazaki, Masanori; Goto, Chikara; Sanada, Hiroaki; Sueda, Taijiro; Chayama, Kazuaki

2010-01-01

The purpose of this study was to determine the effect of a combination of bone marrow mononuclear cell (BM-MNC) implantation and sarpogrelate, a selective 5-HT(2A) antagonist, on endothelial function in patients with critical limb ischemia (CLI). We evaluated the leg blood flow (LBF) responses to acetylcholine (ACh) and sodium nitroprusside before and after BM-MNC implantation in 16 patients with CLI. We divided patients with CLI into 2 groups: those cotreated with sarpogrelate orally for 12 weeks (sarpogrelate group, n = 8) and those who remained on conventional therapy (control group, n = 8). LBF was measured by strain gauge plethysmography. BM-MNC implantation improved ankle brachial pressure index, transcutaneous oxygen pressure, and pain-free walking time. There was no significant difference in these parameters between the 2 groups. Before BM-MNC implantation, LBF responses to ACh were similar in the sarpogrelate group and control group. Twelve weeks of BM-MNC implantation enhanced LBF responses to ACh in the sarpogrelate and control groups. After 12 weeks of BM-MNC implantation, LBF response to ACh was significantly greater in the sarpogrelate group than in the control group. BM-MNC implantation did not alter the LBF responses to sodium nitroprusside in either group. These findings suggest that BM-MNC implantation improved not only limb ischemic symptoms but also endothelium-dependent vasodilation in patients with CLI. A combination of BM-MNC implantation and sarpogrelate had a more beneficial effect on vascular function in these patients.

Coronary In-Stent Restenosis: Assessment with Corrected Coronary Opacification Difference across Coronary Stents Measured with CT Angiography.

Science.gov (United States)

Gao, Yang; Lu, Bin; Hou, Zhi Hui; Yu, Fang Fang; Yin, Wei Hua; Wang, Zhi Qiang; Wu, Yong Jian; Mu, Chao Wei; Meinel, Felix G; McQuiston, Andrew D; Schoepf, U Joseph

2015-05-01

To determine whether changes in coronary opacification normalized to the aorta (corrected coronary opacification [CCO]) across stents can help identify in-stent restenosis (ISR) severity with use of invasive coronary angiography as the standard of reference. This study was approved by the institutional review board, and the requirement to obtain informed consent was waived. The authors retrospectively analyzed 106 patients (88 men, 18 women; mean age, 59.6 years ± 10.4; age range, 36-84 years) who had previously undergone stent implantation within 3 months of coronary computed tomographic (CT) angiography. Attenuation values in the coronary lumen were measured proximal and distal to the stents and normalized to the descending aorta. The CCO difference across the stent was compared with the severity of ISR. One-way analysis of variance least significant difference was used for comparison. A total of 141 stents were assessed. Seventy-six stents were normally patent, 18 had ISR of less than 50%, 28 had ISR of 50%-99%, and 19 were fully occluded. The median CCO differences in the four groups were 0.078, 0.163, 0.346, and 0.606, respectively. There was no significant difference between stents with an ISR of at least 50% and those with total occlusion (P = .056), although the other groups had significant differences at pairwise comparison (P stents smaller than 3 mm in diameter, the median CCO differences in the four groups were 0.086, 0.136, 0.390, and 0.471, respectively. The CCO differences across normal stents and stents with ISR of less than 50% were significantly less than those across stents with an ISR of at least 50% and those with total occlusion (P stents with no ISR and those with an ISR of less than 50% (P = .821) and between stents with an ISR of at least 50% and those with an ISR of 100% (P = .836). The CCO difference across coronary stents is related to ISR severity in obstructive ISR in stents smaller than 3 mm in diameter. © RSNA, 2014.

Coronary tortuosity: a long and winding road.

NARCIS (Netherlands)

Zegers, E.S.; Meursing, B.T.J.; Oude Ophuis, A.J.M.

2007-01-01

Coronary tortuosity is a phenomenon often encountered by cardiologists performing coronary angiography. The aetiology and clinical importance of coronary tortuosity are still unclear. Coronary tortuosity without fixed atherosclerotic stenosis in patients with angina pectoris and an abnormal exercise

Experiment list: DRX014640 [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available s || tissue_type=the endothelium of blood vessels || ihec ref=JTK009 || cell type abbreviation=HCAEC || cell ontology...=endothelial cell of coronary artery || cell ontology uri=http://purl.obolibrary.org/obo/CL_2000018

Experiment list: DRX014644 [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available s || tissue_type=the endothelium of blood vessels || ihec ref=JTK009 || cell type abbreviation=HCAEC || cell ontology...=endothelial cell of coronary artery || cell ontology uri=http://purl.obolibrary.org/obo/CL_2000018

Experiment list: DRX014602 [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available ls || tissue_type=the endothelium of blood vessels || ihec ref=JTK005 || cell type abbreviation=HCAEC || cell ontology...=endothelial cell of coronary artery || cell ontology uri=http://purl.obolibrary.org/obo/CL_200001

Experiment list: DRX014598 [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available lls || tissue_type=the endothelium of blood vessels || ihec ref=JTK005 || cell type abbreviation=HCAEC || cell ontology...=endothelial cell of coronary artery || cell ontology uri=http://purl.obolibrary.org/obo/CL_20000

Experiment list: DRX014600 [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available s || tissue_type=the endothelium of blood vessels || ihec ref=JTK005 || cell type abbreviation=HCAEC || cell ontology...=endothelial cell of coronary artery || cell ontology uri=http://purl.obolibrary.org/obo/CL_2000018

Experiment list: DRX014605 [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available s || tissue_type=the endothelium of blood vessels || ihec ref=JTK005 || cell type abbreviation=HCAEC || cell ontology...=endothelial cell of coronary artery || cell ontology uri=http://purl.obolibrary.org/obo/CL_2000018

Experiment list: DRX014599 [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available ls || tissue_type=the endothelium of blood vessels || ihec ref=JTK005 || cell type abbreviation=HCAEC || cell ontology...=endothelial cell of coronary artery || cell ontology uri=http://purl.obolibrary.org/obo/CL_200001

Experiment list: DRX014601 [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available s || tissue_type=the endothelium of blood vessels || ihec ref=JTK005 || cell type abbreviation=HCAEC || cell ontology...=endothelial cell of coronary artery || cell ontology uri=http://purl.obolibrary.org/obo/CL_2000018

Experiment list: DRX014638 [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available ls || tissue_type=the endothelium of blood vessels || ihec ref=JTK009 || cell type abbreviation=HCAEC || cell ontology...=endothelial cell of coronary artery || cell ontology uri=http://purl.obolibrary.org/obo/CL_200001

Experiment list: DRX014641 [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available ls || tissue_type=the endothelium of blood vessels || ihec ref=JTK009 || cell type abbreviation=HCAEC || cell ontology...=endothelial cell of coronary artery || cell ontology uri=http://purl.obolibrary.org/obo/CL_200001

Experiment list: DRX014597 [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available s || tissue_type=the endothelium of blood vessels || ihec ref=JTK005 || cell type abbreviation=HCAEC || cell ontology...=endothelial cell of coronary artery || cell ontology uri=http://purl.obolibrary.org/obo/CL_2000018

Experiment list: DRX014637 [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available lls || tissue_type=the endothelium of blood vessels || ihec ref=JTK009 || cell type abbreviation=HCAEC || cell ontology...=endothelial cell of coronary artery || cell ontology uri=http://purl.obolibrary.org/obo/CL_20000

Experiment list: DRX014639 [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available ls || tissue_type=the endothelium of blood vessels || ihec ref=JTK009 || cell type abbreviation=HCAEC || cell ontology...=endothelial cell of coronary artery || cell ontology uri=http://purl.obolibrary.org/obo/CL_200001

Experiment list: DRX014636 [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available s || tissue_type=the endothelium of blood vessels || ihec ref=JTK009 || cell type abbreviation=HCAEC || cell ontology...=endothelial cell of coronary artery || cell ontology uri=http://purl.obolibrary.org/obo/CL_2000018

Increased muscle blood supply and transendothelial nutrient and insulin transport induced by food intake and exercise: effect of obesity and ageing.

Science.gov (United States)

Wagenmakers, Anton J M; Strauss, Juliette A; Shepherd, Sam O; Keske, Michelle A; Cocks, Matthew

2016-04-15

This review concludes that a sedentary lifestyle, obesity and ageing impair the vasodilator response of the muscle microvasculature to insulin, exercise and VEGF-A and reduce microvascular density. Both impairments contribute to the development of insulin resistance, obesity and chronic age-related diseases. A physically active lifestyle keeps both the vasodilator response and microvascular density high. Intravital microscopy has shown that microvascular units (MVUs) are the smallest functional elements to adjust blood flow in response to physiological signals and metabolic demands on muscle fibres. The luminal diameter of a common terminal arteriole (TA) controls blood flow through up to 20 capillaries belonging to a single MVU. Increases in plasma insulin and exercise/muscle contraction lead to recruitment of additional MVUs. Insulin also increases arteriolar vasomotion. Both mechanisms increase the endothelial surface area and therefore transendothelial transport of glucose, fatty acids (FAs) and insulin by specific transporters, present in high concentrations in the capillary endothelium. Future studies should quantify transporter concentration differences between healthy and at risk populations as they may limit nutrient supply and oxidation in muscle and impair glucose and lipid homeostasis. An important recent discovery is that VEGF-B produced by skeletal muscle controls the expression of FA transporter proteins in the capillary endothelium and thus links endothelial FA uptake to the oxidative capacity of skeletal muscle, potentially preventing lipotoxic FA accumulation, the dominant cause of insulin resistance in muscle fibres. © 2015 The Authors. The Journal of Physiology © 2015 The Physiological Society.

Auxetic coronary stent endoprosthesis

DEFF Research Database (Denmark)

Amin, Faisal; Ali, Murtaza Najabat; Ansari, Umar

2014-01-01

BACKGROUND: Cardiovascular heart disease is one of the leading health issues in the present era and requires considerable health care resources to prevent it. The present study was focused on the development of a new coronary stent based on novel auxetic geometry which enables the stent to exhibit...... a negative Poisson's ratio. Commercially available coronary stents have isotropic properties, whereas the vascular system of the body shows anisotropic characteristics. This results in a mismatch between anisotropic-isotropic properties of the stent and arterial wall, and this in turn is not favorable...... for mechanical adhesion of the commercially available coronary stents with the arterial wall. It is believed that an auxetic coronary stent with inherent anisotropic mechanical properties and negative Poisson's ratio will have good mechanical adhesion with the arterial wall. METHODS: The auxetic design...

Clinical perspective of coronary computed tomographic angiography in diagnosis of coronary artery disease

International Nuclear Information System (INIS)

Chang, Hyuk-Jae; Chung, Namsik

2011-01-01

Since a 4-detector row coronary computed tomographic angiography (CCTA) was launched in 1998, CCTA has experienced rapid improvement of imaging qualities with the ongoing evolution of computed tomography (CT) technology. The diagnostic accuracy of CCTA to detect coronary artery stenosis is well established, whereas improvements are still needed to reduce the overestimation of coronary artery disease (CAD) and assess plaque composition. CCTA has been used to evaluate CAD in various clinical settings. For example, CCTA could be an efficient initial triage tool at emergency departments for patients with acute chest pain with low-to-intermediate risk because of its high negative predictive value. In patients with suspected CAD, CCTA could be a cost-effective alternative to myocardial perfusion imaging and exercise electrocardiogram for the initial coronary evaluation of patients with intermediate pre-test likelihood suspected CAD. However, in asymptomatic populations, there is a lack of studies that show an improved prognostic power of CCTA over other modalities. Therefore, the clinical use of CCTA to detect CAD for purposes of risk stratification in asymptomatic individuals should be discouraged. As CT technology evolves, CCTA will provide better quality coronary imaging and non-coronary information with lower radiation exposure. Future studies should cover these ongoing technical improvements and evaluate the prognostic power of CCTA in various clinical settings of CAD in large, well-designed, randomized trials. (author)