125 resultados para mineralização arterial
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Les progrès de la médecine ont permis d'améliorer aussi bien la qualité que l'espérance de vie. A ce jour, ceux-ci n'ont malheureusement pas révolutionné la chirurgie vasculaire périphérique. En effet, malgré l'apport de la bio-ingénieurie, les veines restent plus performantes en termes de longévité que les conduits synthétiques dans les interventions de revascularisation réalisées dans le contexte d'une ischémie chronique. Malheureusement, le nombre de veines couramment utilisées et reconnu comme premier choix (veine saphène) et limité.¦L'étude rétrospective réalisée avait pour but de démontrer que les veines des membres supérieurs constituaient plus qu'un dernier choix, plutôt une alternative chez des patients qui ne disposaient plus de veines saphènes ou si celles-ci étaient de mauvaise qualité.¦Nous avons donc revu une série consécutive de patients ayant bénéficié de pontage avec des veines de bras (céphalique, basilique ou mixte) entre 2001 et 2006. L'âge, les commorbidités, les symptômes, ainsi que les rapports angiologiques de ces patients ont également été analysés.¦Pendant ces 5 années, 62 pontages chez 56 patients (6 patients opérés des 2 côtés) utilisant des veines de bras ont été réalisés dans notre service de chirurgie thoracique et vasculaire au CHUV.¦L'analyse des résultats a permis de démontrer que le taux de perméabilité à 3 ans est tout à fait satisfaisant pour les pontages réalisés avec des veines de bras et même comparable à celui obtenu avec les veines saphènes. De plus, nous avons mis en évidence l'importance de la qualité de la veine choisie, l'influence de son diamètre (une augmentation du diamètre de la veine permet une meilleure survie du pontage).¦En conclusion, les veines de bras sont plus qu'un dernier choix dans la revascularisation des membres inférieurs. On devrait prendre en considération leur utilisation à chaque fois qu'elles sont de bonne qualité et d'un diamètre correcte chez les patients qui ne disposent plus de veine saphène, ou même si celles-ci sont présentes, mais de mauvaise qualité. Ceci augmente le nombre de segments veineux à disposition, ce qui permettra d'utiliser encore moins souvent les conduits synthétiques.
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BACKGROUND: In uveal melanoma (UM) with metastatic disease limited to the liver, the effect of an intrahepatic treatment on survival is unknown. We investigated prospectively the efficacy and toxicity of hepatic intra-arterial (HIA) versus systemic (IV) fotemustine in patients with liver metastases from UM. PATIENTS AND METHODS: Patients were randomly assigned to receive either IV or HIA fotemustine at 100 mg/m(2) on days 1, 8, 15 (and 22 in HIA arm only) as induction, and after a 5-week rest period every 3 weeks as maintenance. Primary end point was overall survival (OS). Response rate (RR), progression-free survival (PFS) and safety were secondary end points. RESULTS: Accrual was stopped after randomization of 171 patients based on the results of a futility OS analysis. A total of 155 patients died and 16 were still alive [median follow-up 1.6 years (range 0.25-6 years)]. HIA did not improve OS (median 14.6 months) when compared with the IV arm (median 13.8 months), hazard ratio (HR) 1.09; 95% confidence interval (CI) 0.79-1.50, log-rank P = 0.59. However, there was a significant benefit on PFS for HIA compared with IV with a median of 4.5 versus 3.5 months, respectively (HR 0.62; 95% CI 0.45-0.84, log-rank P = 0.002). The 1-year PFS rate was 24% in the HIA arm versus 8% in the IV arm. An improved RR was seen in the HIA (10.5%) compared with IV treatment (2.4%). In the IV arm, the most frequent grade ≥3 toxicity was thrombocytopenia (42.1%) and neutropenia (62.6%), compared with 21.2% and 28.7% in the HIA arm. The main grade ≥3 toxicity related to HIA was catheter complications (12%) and liver toxicity (4.5%) apart from two toxic deaths. CONCLUSION: HIA treatment with fotemustine did not translate into an improved OS compared with IV treatment, despite better RR and PFS. Intrahepatic treatment should still be considered as experimental. EUDRACT NUMBER AND CLINICALTRIALSGOV IDENTIFIER: 2004-002245-12 and NCT00110123.
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Uveal melanoma metastases occur most commonly in the liver. Given the 50% mortality rate in patients at high risk of developing liver metastases, we tested an adjuvant intra-arterial hepatic (i.a.h.) chemotherapy with fotemustine after proton beam irradiation of the primary tumour. We treated 22 high-risk patients with adjuvant i.a.h. fotemustine. Planned treatment duration was 6 months, starting with four weekly doses of 100 mg/m(2), and after a 5-week rest, repeated every 3 weeks. The survival of this patient group was compared with that of a 3 : 1 matched control group randomly selected from our institutional database. Half of the patients experienced > or =grade 3 hepatotoxicity (one patient developing cholangitis 8 years later). Catheter-related complications occurred in 18%. With a median follow-up of 4.6 years for the fotemustine group and 8.5 years for the control group, median overall survival was 9 years [95% confidence interval (CI) 2.2-12.7] and 7.4 years (95% CI 5.4-12.7; P=0.5), respectively, with 5-year survival rates of 75 and 56%. Treatment with adjuvant i.a.h. fotemustine is feasible. However, toxicities are important. Although our data suggest a survival benefit, it was not statistically significant. Confirming such a benefit would require a large, internationally coordinated, prospective randomized trial.
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INTRODUCTION: Mutations in the TMEM70 are the most common cause of nuclear ATP synthase deficiency resulting in a distinctive phenotype characterized by severe neonatal hypotonia, hypertrophic cardiomyopathy (HCMP), facial dysmorphism, severe lactic acidosis, hyperammonemia and 3-methylglutaconic aciduria (3-MGA). METHODS AND RESULTS: We collected 9 patients with genetically confirmed TMEM70 defect from 8 different families. Six were homozygous for the c.317-2A>G mutation, 2 were compound heterozygous for mutations c.317-2A>G and c.628A>C and 1 was homozygous for the novel c.701A>C mutation. Generalized hypotonia, lactic acidosis, hyperammonemia and 3-MGA were present in all since birth. Five patients presented acute respiratory distress at birth requiring intubation and ventilatory support. HCMP was detected in 5 newborns and appeared a few months later in 3 additional children. Five patients showed a severe and persistent neonatal pulmonary hypertension (PPHN) requiring Nitric Oxide (NO) and/or sildenafil administration combined in 2 cases with high-frequency oscillatory (HFO) ventilation. In 3 of these patients, echocardiography detected signs of HCMP at birth. CONCLUSIONS: PPHN is a life-threatening poorly understood condition with bad prognosis if untreated. Pulmonary hypertension has rarely been reported in mitochondrial disorders and, so far, it has been described in association with TMEM70 deficiency only in one patient. This report further expands the clinical and genetic spectrum of the syndrome indicating PPHN as a frequent and life-threatening complication regardless of the type of mutation. Moreover, in these children PPHN appears even in the absence of an overt cardiomyopathy, thus representing an early sign and a clue for diagnosis.
Arterial properties in relation to genetic variations in the adducin subunits in a white population.
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BACKGROUND: Adducin is a membrane skeleton protein, which consists of either alpha- and beta- or alpha- and gamma-subunits. We investigated whether arterial characteristics might be related to the genes encoding ADD1 (Gly460Trp-rs4961), ADD2 (C1797T-rs4984), and ADD3 (IVS11+386A>G-rs3731566). METHODS: We randomly recruited 1,126 Flemish subjects (mean age, 43.8 years; 50.3% women). Using a wall-tracking ultrasound system, we measured the properties of the carotid, femoral, and brachial arteries. We studied multivariate-adjusted phenotype-genotype associations, using a population- and family-based approach. RESULTS: In single-gene analyses, brachial diameter was 0.15 mm (P = 0.0022) larger, and brachial distensibility and cross-sectional compliance were 1.55 x 10(-3)/kPa (P = 0.013) and 0.017 mm(2)/kPa (P = 0.0029) lower in ADD3 AA than ADD3 GG homozygotes with an additive effect of the G allele. In multiple-gene analyses, the association of brachial diameter and distensibility with the ADD3 G allele occurred only in ADD1 GlyGly homozygotes. Otherwise, the associations between the arterial phenotypes in the three vascular beds and the ADD1 or ADD2 polymorphisms were not significant. In family-based analyses, the multivariate-adjusted heritability was 0.52, 0.38, and 0.30 for brachial diameter, distensibility, and cross-sectional compliance, respectively (P < 0.001). There was no evidence for population stratification (0.07 < or = P < or = 0.96). Transmission of the mutated ADD3 G allele was associated with smaller brachial diameter in 342 informative offspring (-0.12 +/- 0.04 mm; P = 0.0085) and in 209 offspring, who were ADD1 GlyGly homozygotes (-0.14 +/- 0.06 mm; P = 0.018). CONCLUSIONS: In ADD1 GlyGly homozygotes, the properties of the brachial artery are related to the ADD3 (A386G) polymorphism, but the underlying mechanism needs further clarification.
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Abstract Introduction The primary function of the contractile vascular smooth muscle cells (cVSMCs) is the regulation of the vascular contractility which means the adaptation of the vascular tonus in response to the modulation of the blood pressure and blood flow. The cVSMCs are essentially quiescent, and therefore their synthesis rate is very limited. They are characterized by the expression of contractile proteins specific to the muscular tissue including myosin, h-‐caldesmon and <-‐smooth muscle actin (〈-‐SMA). These contractile cells are strongly represented in the media layer of the arterial wall and, in a smaller proportion, of the vein wall. Their typical stretched-‐out morphology allows recognizing them by a histological analysis. They do not produce any extracellular matrix (ECM), and do not migrate through the different layers of the vessel wall, and are not directly involved in the development of intimal hyperplasia (IH). Neointimal formation occurs after endothelial disruption leading to complex molecular and biological mechanisms. The de-‐differentiation of cVSMCs into synthetic VSMCs (sVSMCs) is mentioned as a key element. These non mature cells are able to proliferate and produce ECM. The characterization of the vascular smooth muscle cells (VSMCs) from healthy and stenosed vascular tissues will contribue to the understanding of the different biological processes leading to IH and will be useful for the development of new therapies to interfere with the cVSMCs growth and migration. The aim of our research was to quantify the proportion of cVSMCs and sVSMCs into the healthy and pathologic human blood vessel wall and to characterize their phenotype. Methods We selected 23 specimens of arterial and venous segments from 18 patients. All these specimens were stored in the biobank from the thoracic and vascular surgery departement. 4 groups were designed (group 1 :arteries without lesions (n=3) ;group 2 : veins without lesions (n=1); group 3: arteries with stenosis (n=9); group 4: veins with stenosis (n=10)). Histology: 5µm-‐sections were made from each sample embedded in paraffin wax and further stained with hematoxylin & eosin (HE), Van Gieson's stain (VGEL) and Masson's Trichrome (TMB). Pathologic tissues were defined using the label that was given to the macroscopic samples by the surgeon and also, based on the histological analysis with HE and VGEL evaluating the presence of a thickened intima. The same was done to the control samples evaluating the absence of thickening. Immunohistochemistry : The primary antibodies were used :〈-‐SMA, vimentin, h-‐ caldesmon, calponin, smooth muscle-myosin heavy chain (SM-‐MHC), tropomyosin-‐4, retinol binding protein-‐1 (RBP-‐1), nonmuscle-‐myosin heavy chain-‐B (NM-‐MHC-‐B), Von Willebrand factor (VWF). A semi-‐quantitative assessment of the intensity of each sample stained was performed. Western Blot : Segments of arteries and veins were analyzed using the following primary antibodies :〈-‐SMA, Calponin, SM-‐MHC, NM-‐MHC-‐B. The given results were then normalized with tubulin. Results Our data showed that, when using immunohistochemistry analysis we found that〈-‐SMA was mostly expressed in control arteries, whereas NM-‐MHC-‐B in the pathologic ones. Using SM-‐MHC, calponin, vimentin and caldesmon we found no significative differences in the expression of these proteins in the control and in the pathologic samples. Western Blot analysis showed an inverse correlation between healthy and pathological samples as <-‐ SMA was more expressed in the pathological samples, while NM-‐MHC-‐B in the control group; SM-‐MHC and calponin were mostly expressed in the pathologic samples. Conclusion Our study showed no clear differences between stenotic and control arterial and venous segments using semi-‐quantitative assessement by immunohistochemistry. Western Blot showed a significant increased expression of 〈-‐SMA, calponin and SM-‐MHC in the arteries with stenosis, while NM-‐MHC-‐B was mostly expressed in the arteries without lesions. Further studies are needed to track the lineage of VSMCs to understand the mechanisms leading toIH.
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Conventional coronary magnetic resonance angiography (MRA) techniques display the coronary blood-pool along with the surrounding structures, including the myocardium, the ventricular and atrial blood-pool, and the great vessels. This representation of the coronary lumen is not directly analogous to the information provided by x-ray coronary angiography, in which the coronary lumen displayed by iodinated contrast agent is seen. Analogous "luminographic" data may be obtained using MR arterial spin tagging (projection coronary MRA) techniques. Such an approach was implemented using a 2D selective "pencil" excitation for aortic spin tagging in concert with a 3D interleaved segmented spiral imaging sequence with free-breathing, and real-time navigator technology. This technique allows for selective 3D visualization of the coronary lumen blood-pool, while signal from the surrounding structures is suppressed.
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The aim of the present report is to outline, in concise from, the changes in vascular structure which accompany hypertension. Consideration will be given to their potential contribution to hypertensive end organ damage. In so doing, it is important to consider both the macrovascular and microvascular levels, because interactions between them are presently believed to be critically important. The links between hypertension and the pathogenesis of arteriosclerosis fall outside the scope of this short review.
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To assess the behavior of the arterial wall in hypertensive patients, we developed a noninvasive ultrasonic device. Simultaneous recordings of internal diameter and blood pressure over the whole cardiac cycle are used to establish compliance-pressure curves. Blood pressure, which is a co-determinant of compliance, is thus taken into account. This method allows one to compare arteries from patients with different blood pressures. Arterial compliance and distensibility were first investigated in healthy young volunteers administered either lisinopril (20 mg), atenolol (100 mg) or nitrendipine (20 mg) once a day. After 8 days of treatment, only lisinopril was found to increase arterial compliance. Subsequently, we compared arterial diameter- and distensibility-pressure curves from newly diagnosed and untreated hypertensive patients with those of matched normotensive control patients. Diameter-pressure curves did not differ significantly between the groups and distensibility was not reduced. Similar findings were later obtained in an animal model, when mechanical properties of carotid arteries were compared between spontaneously hypertensive rats and normotensive counterparts (Wistar-Kyoto rats). These results, although interesting by providing noninvasive information on the elastic response of the wall, call for further development of the technique to be able to measure arterial wall thickness. Stress-strain relationship could ultimately be established to thoroughly characterize physical properties of blood vessel walls.
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During recovery from a maximal or submaximal aerobic exercise, augmentation of central (aortic) systolic pressure by reflected pressure waves is blunted in healthy humans. However, the extent to which reflected pressure waves modify the central pulse in diastole in these conditions remains unknown. We evaluated systolic and diastolic central reflected waves in 11 endurance-trained athletes on recovery from a maximal running test on a treadmill (treadmill-max) and a 4000 m run in field conditions. On both occasions in each subject, the radial pulse was recorded with applanation tonometry in the resting preexercise state and then 5, 15, 25, 35, and 45 min after exercise termination. From the central waveform, as reconstructed by application of a generalized transfer function, we computed a systolic (AIx) and a diastolic index (AId) of pressure augmentation by reflections. At 5 min, both indices were below preexercise. At further time-points, AIx remained low, while AId progressively increased, to overshoot above preexercise at 45 min. The same behavior was observed with both exercise types. Beyond the first few minutes of recovery following either maximal or submaximal aerobic exercise, reflected waves selectively augment the central pressure pulse in diastole, at least in endurance-trained athletes.
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Background: Transcatheter arterial chemoembolization (TACE) has been shown to offer a survival benefit for patients with intermediate-stage hepatocellular carcinoma (HCC). A widely accepted TACE regimen includes the administration of a doxorubicin-in-oil emulsion followed by gelatine sponge particles. Recently, a drug-eluting bead (DEB) has been developed to enhance drug delivery to the tumor and reduce its systemic availability. Purpose of this randomized trial was to compare conventional TACE with DEB-TACE for the treatment of intermediate-stage HCC in patients with cirrhosis. Methods: Two hundred and twelve patients (185 males and 27 females; mean age, 67 years) with Child-Pugh A or B liver cirrhosis and large and/or multinodular, unresectable HCC were randomized to receive DEB-TACE (DC Bead; Biocompatibles, UK) uploaded with doxorubicin or conventional TACE with doxorubicin, lipiodol, and gelatin sponge particles. Randomization was stratified according to Child Pugh status (A or B), performance status (ECOG 0 or 1), bilobar disease (yes or no) and prior curative treatment (yes or no). Tumor response at 6 months was the primary study endpoint. An independent, blinded review of magnetic resonance imaging studies was conducted to assess tumor response according to amended RECIST criteria. Results: DEB-TACE with doxorubicin showed a higher rate of complete response, objective response and disease control compared with conventional TACE (27% vs 22%; 52% vs 44%; and 63% vs 52%, respectively; p>0.05). Patients with Child Pugh B, ECOG 1, bilobar disease and recurrence following curative treatment showed a significant increase in objective response (p=0.038) compared to the control. There was a marked reduction in serious liver toxicity in patients treated with DEB-TACE. The rate of doxorubicin related side effects was significantly lower (p=0.0001) in the DEB-TACE group compared with the conventional TACE group. Conclusions: DEB-TACE with doxorubicin is safe and effective in the treatment of intermediate-stage HCC and may offer benefit to patients with more advanced disease.
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We report a case of a fifty year old woman with Graves' disease with positive AntiTPO antibodies and positive AntiTSH receptor antibodies, who was hospitalized with a right cardiac failure. A pulmonary hypertension was discovered on echocardiography. After adequate antithyroid therapy, the right cardiac failure regressed rapidly and pulmonary pressure normalised. An autoimmune process has often been proposed to explain the association between pulmonary hypertension and hyperthyroidism. We report the arguments supporting this autoimmune etiopathogenesis. We also discuss an other hypothesis based on a direct effect of thyroid hormones on the pulmonary circulation and the effects of high cardiac output associated with hyperthyroidism.
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Blood pressure is abnormally elevated in acute stroke in most patients. This blood pressure increase is usually transient and associated with a poor prognosis. Lowering blood pressure too importantly during this period may worsen the outcome of the patient. Antihypertensive therapy is therefore required only when blood pressure is severely increased, especially in the presence of intracerebral haemorrhage. Initiating treatment before admission to the hospital is not recommended. The medications to be preferred are the blockers of the renin-angiotensin system, the beta-blocker labetalol (which possesses also alpha-blocking properties) and NO donors.
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BACKGROUND AND PURPOSE: A right-to-left shunt can be identified by contrast transcranial Doppler ultrasonography (c-TCD) at rest and/or after a Valsalva maneuver (VM) or by arterial blood gas (ABG) measurement. We assessed the influence of controlled strain pressures and durations during VM on the right-to-left passage of microbubbles, on which depends the shunt classification by c-TCD, and correlated it with the right-to-left shunt evaluation by ABG measurements in stroke patients with patent foramen ovale (PFO). METHODS: We evaluated 40 stroke patients with transesophageal echocardiography-documented PFO. The microbubbles were recorded with TCD at rest and after 4 different VM conditions with controlled duration and target strain pressures (duration in seconds and pressure in cm H2O, respectively): V5-20, V10-20, V5-40, and V10-40. The ABG analysis was performed after pure oxygen breathing in 34 patients, and the shunt was calculated as percentage of cardiac output. RESULTS: Among all VM conditions, V5-40 and V10-40 yielded the greatest median number of microbubbles (84 and 95, respectively; P<0.01). A significantly larger number of microbubbles were detected in V5-40 than in V5-20 (P<0.001) and in V10-40 than in V10-20 (P<0.01). ABG was not sensitive enough to detect a shunt in 31 patients. CONCLUSIONS: The increase of VM expiratory pressure magnifies the number of microbubbles irrespective of the strain duration. Because the right-to-left shunt classification in PFO is based on the number of microbubbles, a controlled VM pressure is advised for a reproducible shunt assessment. The ABG measurement is not sensitive enough for shunt assessment in stroke patients with PFO.