330 resultados para Dilatation


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Although it is known that obesity, diabetes, and Kawasaki's disease play important roles in systemic inflammation and in the development of both endothelial dysfunction and cardiomyopathy, there is a lack of data regarding the endothelial function of pre-pubertal children suffering from cardiomyopathy. In this study, we performed a systematic review of the literature on pre-pubertal children at risk of developing cardiomyopathy to assess the endothelial function of pre-pubertal children at risk of developing cardiomyopathy. We searched the published literature indexed in PubMed, Bireme and SciELO using the keywords 'endothelial', 'children', 'pediatric' and 'infant' and then compiled a systematic review. The end points were age, the pubertal stage, sex differences, the method used for the endothelial evaluation and the endothelial values themselves. No studies on children with cardiomyopathy were found. Only 11 papers were selected for our complete analysis, where these included reports on the flow-mediated percentage dilatation, the values of which were 9.80±1.80, 5.90±1.29, 4.50±0.70, and 7.10±1.27 for healthy, obese, diabetic and pre-pubertal children with Kawasaki's disease, respectively. There was no significant difference in the dilatation, independent of the endothelium, either among the groups or between the genders for both of the measurements in children; similar results have been found in adolescents and adults. The endothelial function in cardiomyopathic children remains unclear because of the lack of data; nevertheless, the known dysfunctions in children with obesity, type 1 diabetes and Kawasaki's disease may influence the severity of the cardiovascular symptoms, the prognosis, and the mortality rate. The results of this study encourage future research into the consequences of endothelial dysfunction in pre-pubertal children.

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Background/objectives: Therapy using bone marrow (BM) cells has been tested experimentally and clinically due to the potential ability to restore cardiac function by regenerating lost myocytes or increasing the survival of tissues at risk after myocardial infarction (MI). In this study we aimed to evaluate whether BM-derived mononuclear cell (MNC) implantation can positively influence the post-MI structural remodeling, contractility and Ca(2 +)-handling proteins of the remote non-infarcted tissue in rats. Methods and results: After 48 h of MI induction, saline or BM-MNC were injected. Six weeks later, MI scars were slightly smaller and thicker, and cardiac dilatation was just partially prevented by cell therapy. However, the cardiac performance under hemodynamic stress was totally preserved in the BM-MNC treated group if compared to the untreated group, associated with normal contractility of remote myocardium as analyzed in vitro. The impaired post-rest potentiation of contractile force, associated with decreased protein expression of the sarcoplasmic reticulum Ca2 +-ATPase and phosphorylated-phospholamban and overexpression of Na(+)/Ca(2 +) exchanger, were prevented by BM-MNC, indicating preservation of the Ca(2 +) handling. Finally, pathological changes on remodeled remote tissue such as myocyte hypertrophy, interstitial fibrosis and capillary rarefaction were also mitigated by cell therapy. Conclusions: BM-MNC therapy was able to prevent cardiac structural and molecular remodeling after MI, avoiding pathological changes on Ca(2 +)-handling proteins and preserving contractile behavior of the viable myocardium, which could be the major contributor to the improvements of global cardiac performance after cell transplantation despite that scar tissue still exists.

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Extensive literature outlined that the quality of the mother-foetus relationship is considered the main feature with regard to the quality of postnatal mother-infant interaction and also to the child’s psychical development. Nowadays the relationship between the pregnant woman and her foetus is viewed as the central factor of the somatic dialogue between the functioning of the maternal and the foetal organisms. This dialogue is responsible for the physic development of the child, as well as of its psychosomatic structure. Therefore the research area has necessarily had to extend to the analysis of psychological processes concerning: the pregnancy, the couple that is bound by parenthood, the influence of intergenerational dynamics. In fact, the formation of maternal identity, as well as that of the relationship between the woman and the foetus, refers to the pregnant woman’s relationship with her parents, especially with her mother. The same pregnancy, considered as a psychosomatic event, is directly influenced by relational, affective and social factors, particularly by the quality of the interiorized parental relations and the quality of the current relationships (such as that with her partner and with her family of origin). Some studies have begun to investigate the relationship between the pregnant woman and the foetus in term of “prenatal attachment” and its relationship with socio-demographic, psychological e psychopathological aspects (such as pre and post partum depression), but the research area is still largely unexplored. The present longitudinal research aimed to investigate the quality of the pregnant womanfoetus relationship by the prenatal attachment index, the quality of the interiorized relationship with woman’s parents, the level of alexithymic features and maternity social support, in relation with the modulation of the physiology of delivery and of postpartum, as well as of the physical development of the child. A consecutive sample of 62 Italian primipara women without any kind of pathologies, participated in the longitudinal study. In the first phase of this study (third trimester of the pregnancy), it has investigated the psychological processes connected to the affective investment of the pregnant women towards the unborn baby (by Prenatal Attachment Inventory), the mothers’ interiorized relationship with their own parents (by Parental Bonding Instrument), the social and affective support from their partner and their family of origin are able to supply (by Maternity Social Support Scale), and the level of alexithymia (by 20-Toronto Alexithymia Scale). In the second phase of this study, some data concerning the childbirth course carried out from a “deliverygram” (such as labour, induction durations and modalities of delivery) and data relative to the newborns state of well-being (such as Apgar and pH indexes). Finally, in the third phase of the study women have been telephoned a month after the childbirth. The semistructured interview investigated the following areas: the memory concerning the delivery, the return to home, the first interactions between the mother and the newborn, the breastfeeding, the biological rhythms achieved from newborns. From the data analysis a sample with a good level of prenatal attachment and of support social and a good capability to mental functioning emerged. An interesting result is that the most of the women have a great percentage of “affectionless control style” with both parents, but data is not sufficient to interpret this result. Moreover, considering the data relative to the delivery, medical and welfare procedures, that have been necessary, are coherent with the Italian mean, while the percentage of the caesarean section (12.9%) is inferior to the national percentage (30%). The 29% of vaginal partum has got epidural analgesia, which explains the high number (37%) of obstetrician operations (such as Kristeller). The data relative to the newborn (22 male, 40 female) indicates a good state of well-being because Apgar and pH indexes are superior to 7 at first and fifth minutes. Concerning the prenatal phase, correlation analysis showed that: the prenatal attachment scores positively correlated with the expected social support and negatively correlated with the “externally oriented thinking” dimension of alexithymia; the maternity social support negatively correlated with total alexithymia score, particularly with the “externally oriented thinking” dimension, and negatively correlated with maternal control of parental bonding. Concerning the delivery data, there are many correlations (after all obvious) among themselves. The most important are that the labour duration negatively correlated with the newborn’s index state of well-being. Finally, concerning the data from the postpartum phase the women’ assessments relative to the partum negatively correlated with the duration of the delivery and positively correlated with the assessment relative to the return to home and the interaction with the newborn. Moreover the length of permanence in the hospital negatively correlated with women’s assessments relative to the return to home that, in turn, positively correlated with the quality of breastfeeding, the interaction between the mother and the newborn and the biological regulation of the child. Finally, the women’ assessments relative to breastfeeding positively correlated with the mother-child interactions and the biological rhythms of children. From the correlation analysis between the variables of the prenatal phase and the data relative to the delivery, emerged that the prenatal attachment scores positively correlated with the dilatation stage scores and with the newborn’s Apgar index at first minute, the paternal care dimension of parental bonding positively correlated with the lengths of the various periods of childbirth like so the paternal control dimension with placental stage. Moreover, emerged that the expected social support positively correlated with the lengths of the various periods of childbirth and that the global alexithymia scores, particularly “difficulty to describe emotions” dimension, negatively correlated with total childbirth scores. From the correlation analysis between the variables of the prenatal phase and variable of the postpartum phase emerged that the total alexithymia scores positively correlated with the time elapsed from the childbirth to the breastfeeding of the child, the difficulty to describe emotions dimension of the alexithymia negatively correlated with the quality of the breastfeeding, the “externally oriented thinking” dimension of the alexithymia negatively correlated with mother-child interactions, and finally the paternal control dimension of the parental bonding negatively correlated with the time elapsed from the child to the breastfeeding of the child. Finally, from the analysis of the correlation between the data of the partum and the women’s assessments of the postpartum phase, emerged the negative correlation between the woman’s assessment relative to the delivery and the quantitative of obstetrician operations and the lengths of the various periods of childbirth, the positive correlation between the women’s assessment about the length of delivery periods and the real lengths of the same ones, the positive relation between woman’s assessment relative to the delivery and the Apgar index of children. In conclusion, there is a remarkable relation between the quality of the relationship the woman establishes with the foetus that influences the course of the pregnancy and the delivery that, in turn, influences the postpartum outcome, particularly relative to the mother-children relationship. Such data should be confirmed by heterogeneous populations in order to identify vulnerable women and to project focused intervention.

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In this thesis, we present our work about some generalisations of ideas, techniques and physical interpretations typical for integrable models to one of the most outstanding advances in theoretical physics of nowadays: the AdS/CFT correspondences. We have undertaken the problem of testing this conjectured duality under various points of view, but with a clear starting point - the integrability - and with a clear ambitious task in mind: to study the finite-size effects in the energy spectrum of certain string solutions on a side and in the anomalous dimensions of the gauge theory on the other. Of course, the final desire woul be the exact comparison between these two faces of the gauge/string duality. In few words, the original part of this work consists in application of well known integrability technologies, in large parte borrowed by the study of relativistic (1+1)-dimensional integrable quantum field theories, to the highly non-relativisic and much complicated case of the thoeries involved in the recent conjectures of AdS5/CFT4 and AdS4/CFT3 corrspondences. In details, exploiting the spin chain nature of the dilatation operator of N = 4 Super-Yang-Mills theory, we concentrated our attention on one of the most important sector, namely the SL(2) sector - which is also very intersting for the QCD understanding - by formulating a new type of nonlinear integral equation (NLIE) based on a previously guessed asymptotic Bethe Ansatz. The solutions of this Bethe Ansatz are characterised by the length L of the correspondent spin chain and by the number s of its excitations. A NLIE allows one, at least in principle, to make analytical and numerical calculations for arbitrary values of these parameters. The results have been rather exciting. In the important regime of high Lorentz spin, the NLIE clarifies how it reduces to a linear integral equations which governs the subleading order in s, o(s0). This also holds in the regime with L ! 1, L/ ln s finite (long operators case). This region of parameters has been particularly investigated in literature especially because of an intriguing limit into the O(6) sigma model defined on the string side. One of the most powerful methods to keep under control the finite-size spectrum of an integrable relativistic theory is the so called thermodynamic Bethe Ansatz (TBA). We proposed a highly non-trivial generalisation of this technique to the non-relativistic case of AdS5/CFT4 and made the first steps in order to determine its full spectrum - of energies for the AdS side, of anomalous dimensions for the CFT one - at any values of the coupling constant and of the size. At the leading order in the size parameter, the calculation of the finite-size corrections is much simpler and does not necessitate the TBA. It consists in deriving for a nonrelativistc case a method, invented for the first time by L¨uscher to compute the finite-size effects on the mass spectrum of relativisic theories. So, we have formulated a new version of this approach to adapt it to the case of recently found classical string solutions on AdS4 × CP3, inside the new conjecture of an AdS4/CFT3 correspondence. Our results in part confirm the string and algebraic curve calculations, in part are completely new and then could be better understood by the rapidly evolving developments of this extremely exciting research field.

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Diese Doktorarbeit untersucht das Verhalten von komplexenFluidenunter Scherung, insbesondere den Einfluss von Scherflüssenauf dieStrukturbildung.Dazu wird ein Modell dieser entworfen, welches imRahmen von Molekulardynamiksimulationen verwendet wird.Zunächst werden Gleichgewichtseigenschaften dieses Modellsuntersucht.Hierbei wird unter anderem die Lage desOrdnungs--Unordnungsübergangs von derisotropen zur lamellaren Phase der Dimere bestimmt.Der Einfluss von Scherflüssen auf diese lamellare Phase wirdnununtersucht und mit analytischen Theorien verglichen. Die Scherung einer parallelen lamellaren Phase ruft eineNeuausrichtung des Direktors in Flussrichtung hervor.Das verursacht eine Verminderung der Schichtdicke mitsteigender Scherrateund führt oberhalb eines Schwellwertes zu Ondulationen.Ein vergleichbares Verhalten wird auch in lamellarenSystemengefunden, an denen in Richtung des Direktors gezogen wird.Allerdings wird festgestellt, dass die Art der Bifurkationenin beidenFällen unterschiedlich ist.Unter Scherung wird ein Übergang von Lamellen parallelerAusrichtung zu senkrechter gefunden.Dabei wird beoachtet, dass die Scherspannung in senkrechterOrientierungniedriger als in der parallelen ist.Dies führt unter bestimmten Bedingungen zum Auftreten vonScherbändern, was auch in Simulationen beobachtet wird. Es ist gelungen mit einem einfachen Modell viele Apsekte desVerhalten vonkomplexen Fluiden wiederzugeben. Die Strukturbildung hängt offensichtlich nurbedingt von lokalen Eigenschaften der Moleküle ab.

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Das Auftreten von Psychostimulantien im Straßenverkehr und eine Beeinträchtigung der Fahrtüchtigkeit durch diese spielt in Deutschland zunehmend eine wichtige Rolle. Das Ziel der hier vorliegenden Arbeit war es retrospektiv die dokumentierten Ausfallserscheinungen von Personen unter Einfluss von Amphetaminderivaten anhand von ärztlichen Untersuchungsbögen, die bei polizeilich angeordneten Blutentnahmen ausgefüllt werden, des Zeitraums 2001 bis 2005 in Rheinland-Pfalz zu untersuchen. Aufgrund der hohen Fallzahlen konnten sehr strenge Auswahlkriterien angewandt werden, sodass lediglich reine Amphetaminderivat-Intoxikationen (Amphetamin, Methamphetamin, MDA, MDMA, MDE, MBDB) bei 923 Personen untersucht werden konnten. Es zeigten sich als verkehrsrelevante Beeinflussung die Erweiterung der Pupille mit einer geringeren Lichtreagibilität, eine Verlängerung des Drehnachnystagmus sowie eine Unsicherheit beim Rombergtest. Eine Dosis-Wirkungs-Beziehung konnte lediglich bei der Pupillenweite ansatzweise gefunden werden. Bei MDMA zeigte sich ein deutlich stärkerer Einfluss auf die Pupillenweitenregulation als bei Amphetamin. Die zur Detektion von alkoholbedingten Ausfallserscheinungen sinnvollen Gleichgewichts- und Koordinationstests waren im Falle der hier betrachteten Psychstimulantien nicht aussagekräftig. Es erscheint empfehlenswert die durchgeführten Untersuchungen mit Hilfe von einheitlichen Lichtverhältnissen und festgelegten Untersuchungsprozedere zu standardisieren ggf. auch durch die Einführung der Videookulographie. Die Einführung eines Reaktionstests sollte in Erwägung gezogen werden.

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La Valvola Aortica Bicuspide (BAV) rappresenta la più comune anomalia cardiaca congenita, con un’incidenza dello 0,5%-2% nella popolazione generale. Si caratterizza per la presenza di due cuspidi valvolari anziché tre e comprende diverse forme. La BAV è frequentemente associata agli aneurismi dell’aorta toracica (TAA). La dilatazione dell’aorta espone al rischio di sviluppare le complicanze aortiche acute. Materiali e metodi Sono stati reclutati 20 probandi consecutivi sottoposti a chirurgia della valvola aortica e dell'aorta ascendente presso l'Unità di Chirurgia Cardiaca di Policlinico S.Orsola-Malpighi di TAA associata a BAV. Sono stati esclusi individui con una condizione sindromica predisponente l’aneurisma aortico. Ciascun familiare maggiorenne di primo grado è stato arruolato nello studio. L’analisi di mutazioni dell’intero gene ACTA2 è stata eseguita con la tecnica del “bidirectional direct sequencing”. Nelle forme familiari, l’intera porzione codificante del genoma è stata eseguita usando l’exome sequencing. Risultati Dopo il sequenziamento di tutti i 20 esoni e giunzioni di splicing di ACTA2 nei 20 probandi, non è stata individuata alcuna mutazione. Settantasette familiari di primo grado sono stati arruolati. Sono state identificate cinque forme familiari. In una famiglia è stata trovata una mutazione del gene MYH11 non ritenuta patogenetica. Conclusioni La mancanza di mutazioni, sia nelle forme sporadiche sia in quelle familiari, ci suggerisce che questo gene non è coinvolto nello sviluppo della BAV e TAA e, l’associazione che è stata riportata deve essere considerata occasionale. L’architettura genetica della BAV verosimilmente dovrebbe consistere in svariate differenti varianti genetiche che interagiscono in maniera additiva nel determinare un aumento del rischio.

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Granular matter, also known as bulk solids, consists of discrete particles with sizes between micrometers and meters. They are present in many industrial applications as well as daily life, like in food processing, pharmaceutics or in the oil and mining industry. When handling granular matter the bulk solids are stored, mixed, conveyed or filtered. These techniques are based on observations in macroscopic experiments, i.e. rheological examinations of the bulk properties. Despite the amply investigations of bulk mechanics, the relation between single particle motion and macroscopic behavior is still not well understood. For exploring the microscopic properties on a single particle level, 3D imaging techniques are required.rnThe objective of this work was the investigation of single particle motions in a bulk system in 3D under an external mechanical load, i.e. compression and shear. During the mechanical load the structural and dynamical properties of these systems were examined with confocal microscopy. Therefor new granular model systems in the wet and dry state were designed and prepared. As the particles are solid bodies, their motion is described by six degrees of freedom. To explore their entire motion with all degrees of freedom, a technique to visualize the rotation of spherical micrometer sized particles in 3D was developed. rnOne of the foci during this dissertation was a model system for dry cohesive granular matter. In such systems the particle motion during a compression of the granular matter was investigated. In general the rotation of single particles was the more sensitive parameter compared to the translation. In regions with large structural changes the rotation had an earlier onset than the translation. In granular systems under shear, shear dilatation and shear zone formation were observed. Globally the granular sediments showed a shear behavior, which was known already from classical shear experiments, for example with Jenike cells. Locally the shear zone formation was enhanced, when near the applied load a pre-diluted region existed. In regions with constant volume fraction a mixing between the different particle layers occurred. In particular an exchange of particles between the current flowing region and the non-flowing region was observed. rnThe second focus was on model systems for wet granular matter, where an additional binding liquid is added to the particle suspension. To examine the 3D structure of the binding liquid on the micrometer scale independently from the particles, a second illumination and detection beam path was implemented. In shear and compression experiments of wet clusters and bulk systems completely different dynamics compared to dry cohesive models systems occured. In a Pickering emulsion-like system large structural changes predominantly occurred in the local environment of binding liquid droplets. These large local structural changes were due to an energy interplay between the energy stored in the binding droplet during its deformation and the binding energy of particles at the droplet interface. rnConfocal microscopy in combination with nanoindentation gave new insights into the single particle motions and dynamics of granular systems under a mechanical load. These novel experimental results can help to improve the understanding of the relationship between bulk properties of granular matter, such as volume fraction or yield stress and the dynamics on a single particle level.rnrn

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Aortic dilatation/dissection (AD) can occur spontaneously or in association with genetic syndromes, such as Marfan syndrome (MFS; caused by FBN1 mutations), MFS type 2 and Loeys-Dietz syndrome (associated with TGFBR1/TGFBR2 mutations), and Ehlers-Danlos syndrome (EDS) vascular type (caused by COL3A1 mutations). Although mutations in FBN1 and TGFBR1/TGFBR2 account for the majority of AD cases referred to us for molecular genetic testing, we have obtained negative results for these genes in a large cohort of AD patients, suggesting the involvement of additional genes or acquired factors. In this study we assessed the effect of COL3A1 deletions/duplications in this cohort. Multiplex ligation-dependent probe amplification (MLPA) analysis of 100 unrelated patients identified one hemizygous deletion of the entire COL3A1 gene. Subsequent microarray analyses and sequencing of breakpoints revealed the deletion size of 3,408,306 bp at 2q32.1q32.3. This deletion affects not only COL3A1 but also 21 other known genes (GULP1, DIRC1, COL5A2, WDR75, SLC40A1, ASNSD1, ANKAR, OSGEPL1, ORMDL1, LOC100129592, PMS1, MSTN, C2orf88, HIBCH, INPP1, MFSD6, TMEM194B, NAB1, GLS, STAT1, and STAT4), mutations in three of which (COL5A2, SLC40A1, and MSTN) have also been associated with an autosomal dominant disorder (EDS classical type, hemochromatosis type 4, and muscle hypertrophy). Physical and laboratory examinations revealed that true haploinsufficiency of COL3A1, COL5A2, and MSTN, but not that of SLC40A1, leads to a clinical phenotype. Our data not only emphasize the impact/role of COL3A1 in AD patients but also extend the molecular etiology of several disorders by providing hitherto unreported evidence for true haploinsufficiency of the underlying gene.

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Hypertension represents a complex, multifactorial disease and contributes to the major causes of morbidity and mortality in industrialized countries: ischemic and hypertensive heart disease, stroke, peripheral atherosclerosis and renal failure. Current pharmacological therapy of essential hypertension focuses on the regulation of vascular resistance by inhibition of hormones such as catecholamines and angiotensin II, blocking them from receptor activation. Interaction of G-protein coupled receptor kinases (GRKs) and regulator of G-protein signaling (RGS) proteins with activated G-protein coupled receptors (GPCRs) effect the phosphorylation state of the receptor leading to desensitization and can profoundly impair signaling. Defects in GPCR regulation via these modulators have severe consequences affecting GPCR-stimulated biological responses in pathological situations such as hypertension, since they fine-tune and balance the major transmitters of vessel constriction versus dilatation, thus representing valuable new targets for anti-hypertensive therapeutic strategies. Elevated levels of GRKs are associated with human hypertensive disease and are relevant modulators of blood pressure in animal models of hypertension. This implies therapeutic perspective in a disease that has a prevalence of 65million in the United States while being directly correlated with occurrence of major adverse cardiac and vascular events. Therefore, therapeutic approaches using the inhibition of GRKs to regulate GPCRs are intriguing novel targets for treatment of hypertension and heart failure.

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Mitral regurgitation (MR) involves systolic retrograde flow from the left ventricle into the left atrium. While trivial MR is frequent in healthy subjects, moderate to severe MR constitutes the second most prevalent valve disease after aortic valve stenosis. Major causes of severe MR in Western countries include degenerative valve disease (myxomatous disease, flail leaflet, annular calcification) and ischaemic heart disease, while rheumatic disease remains a major cause of MR in developing countries. Chronic MR typically progresses insidiously over many years. Once established, however, severe MR portends a poor prognosis. The severity of MR can be assessed by various techniques, Doppler echocardiography being the most widely used. Mitral valve surgery is the only treatment of proven efficacy. It alleviates clinical symptoms and prevents ventricular dilatation and heart failure (or, at least, it attenuates further progression of these abnormalities). Valve repair significantly improves clinical outcomes compared with valve replacement, reducing mortality by approximately 70%. Reverse LV remodelling after valve repair occurs in half of patients with functional MR. Percutaneous, catheter-based to mitral valve repair is a novel approach currently under clinical scrutiny, with encouraging preliminary results. This modality may provide a valuable alternative to mitral valve surgery, especially in critically ill patients.

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Radiodermatitis is a known complication in patients having undergone radiotherapy. It usually appears 2 to 5 years after irradiation. We are reporting on a case of radiodermatitis that occurred within months after coronary dilatation and stenting. It started with painful swelling, followed by a typical appearance on the skin surface. Histological finding confirmed the diagnosis. However, magnetic resonance imaging showed changes in the subcutaneous tissue extending into the ribs. A radical debridement was performed including removal of a partially necrotic 4th rib. The defect was closed with a latissimus dorsi transposition flap. Our findings are compared with the literature reports.

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Long-term endurance sports are associated with atrial remodeling and atrial arrhythmias. More importantly, high-level endurance training may promote right ventricular (RV) dysfunction and complex ventricular arrhythmias. We investigated the long-term consequences of marathon running on cardiac remodeling as a potential substrate for arrhythmias with a focus on the right heart. We invited runners of the 2010 Grand Prix of Bern, a 10-mile race. Of 873 marathon and nonmarathon runners who applied, 122 (61 women) entered the final analysis. Subjects were stratified according to former marathon participations: control group (nonmarathon runners, n = 34), group 1 (1 marathon to 5 marathons, mean 2.7, n = 46), and group 2 (≥6 marathons, mean 12.8, n = 42). Mean age was 42 ± 7 years. Results were adjusted for gender, age, and lifetime training hours. Right and left atrial sizes increased with marathon participations. In group 2, right and left atrial enlargements were present in 60% and 74% of athletes, respectively. RV and left ventricular (LV) dimensions showed no differences among groups, and RV or LV dilatation was present in only 2.4% or 4.3% of marathon runners, respectively. In multiple linear regression analysis, marathon participation was an independent predictor of right and left atrial sizes but had no effect on RV and LV dimensions and function. Atrial and ventricular ectopic complexes during 24-hour Holter monitoring were low and equally distributed among groups. In conclusion, in nonelite athletes, marathon running was not associated with RV enlargement, dysfunction, or ventricular ectopy. Marathon running promoted biatrial remodeling.

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BACKGROUND: The arterial switch operation (ASO) is currently the treatment of choice in neonates with transposition of the great arteries (TGA). The outcome in childhood is encouraging but only limited data for long-term outcome into adulthood exist. METHODS AND RESULTS: We studied 145 adult patients (age>16, median 25years) with ASO followed at our institution. Three patients died in adulthood (mortality 2.4/1000-patient-years). Most patients were asymptomatic and had normal left ventricular function. Coronary lesions requiring interventions were rare (3 patients) and in most patients related to previous surgery. There were no acute coronary syndromes. Aortic root dilatation was frequent (56% patients) but rarely significant (>45mm in 3 patients, maximal-diameter 49mm) and appeared not to be progressive. There were no acute aortic events and no patient required elective aortic root surgery. Progressive neo-aortic-valve dysfunction was not observed in our cohort and only 1 patient required neo-aortic-valve replacement. Many patients (42.1%), however, had significant residual lesions or required reintervention in adulthood. Right ventricular outflow tract lesions or dysfunction of the neo-pulmonary-valve were frequent and 8 patients (6%) required neo-pulmonary-valve replacement. Cardiac interventions during childhood (OR 3.0, 95% CI 1.7-5.4, P<0.0001) were strong predictors of outcome (cardiac intervention/significant residual lesion/death) in adulthood. CONCLUSIONS: Adult patients with previous ASO remain free of acute coronary or aortic complications and have low mortality. However, a large proportion of patients require re-interventions or present with significant right sided lesions. Life-long cardiac follow-up is, therefore, warranted. Periodic noninvasive surveillance for coronary complications appears to be safe in adult ASO patients.

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Vascular surgical training currently has to cope with various challenges, including restrictions on work hours, significant reduction of open surgical training cases in many countries, an increasing diversity of open and endovascular procedures, and distinct expectations by trainees. Even more important, patients and the public no longer accept a "learning by doing" training philosophy that leaves the learning curve on the patient's side. The Vascular International (VI) Foundation and School aims to overcome these obstacles by training conventional vascular and endovascular techniques before they are applied on patients. To achieve largely realistic training conditions, lifelike pulsatile models with exchangeable synthetic arterial inlays were created to practice carotid endarterectomy and patch plasty, open abdominal aortic aneurysm surgery, and peripheral bypass surgery, as well as for endovascular procedures, including endovascular aneurysm repair, thoracic endovascular aortic repair, peripheral balloon dilatation, and stenting. All models are equipped with a small pressure pump inside to create pulsatile flow conditions with variable peak pressures of ~90 mm Hg. The VI course schedule consists of a series of 2-hour modules teaching different open or endovascular procedures step-by-step in a standardized fashion. Trainees practice in pairs with continuous supervision and intensive advice provided by highly experienced vascular surgical trainers (trainer-to-trainee ratio is 1:4). Several evaluations of these courses show that tutor-assisted training on lifelike models in an educational-centered and motivated environment is associated with a significant increase of general and specific vascular surgical technical competence within a short period of time. Future studies should evaluate whether these benefits positively influence the future learning curve of vascular surgical trainees and clarify to what extent sophisticated models are useful to assess the level of technical skills of vascular surgical residents at national or international board examinations. This article gives an overview of our experiences of >20 years of practical training of beginners and advanced vascular surgeons using lifelike pulsatile vascular surgical training models.