51 research outputs found

    Various clinical scenarios leading to development of the string sign of the internal thoracic artery after coronary bypass surgery: the role of competitive flow, a case series

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    <p>Abstract</p> <p>Background</p> <p>The left internal mammary artery (LIMA) is the choice for grafting of the left anterior descending coronary artery (LAD). One possible mechanism of the rare graft failure involve the presence of competitive flow.</p> <p>Method</p> <p>105 patients who had undergone coronary bypass grafting between 1998 and 2000 were included in this observational study. The recatheterizations were performed 28 months after the operations. The rate of patency the LIMA grafts was determined, and the cases with graft failure were analyzed.</p> <p>Results</p> <p>The LIMA graft was patent in 99 patients (94%). Six patients (6%) exhibited diffuse involution of the graft (string sign). The string sign was always associated with competitive flow as the basis of the LIMA graft involution. In one case quantitative re-evaluation of the preoperative coronary angiography revealed merely less than 50% diameter stenosis on the LAD with a nonligated side-branch of the LIMA. At recatheterization in two patients the pressure wire measurements demonstrated only a non-significant decrease of the fractional flow reserve (0.83 and 0.89), despite the 53% and 57% diameter stenosis in the angiogram. Another patient displayeda significant regression of the LAD lesion between the pre- and postoperative coronary angiography (from 76% to 44%) as the cause of the development of the competitive flow. In one instance, a radial artery graft on the LAD during a redo bypass operation resulted in competitive flow in the radial graft due to the greater diameter than that of the LIMA. In a further patient, competitive flow developed from a short sequential part of the LIMA graft between the nonsignificantly stenosed diagonal branch and the LAD, with involution of the main part of the graft to the diagonal branch.</p> <p>Conclusions</p> <p>The most common cause of the development of the string sign of a LIMA graft due to competitive flow is overassessment of the lesion of the LAD. Regression of a previous lesion or some other neighboring graft can also cause the phenomenon.</p

    A spatially-VSL gravity model with 1-PN limit of GRT

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    A scalar gravity model is developed according the 'geometric conventionalist' approach introduced by Poincare (Einstein 1921, Poincare 1905, Reichenbach 1957, Gruenbaum1973). In principle this approach allows an alternative interpretation and formulation of General Relativity Theory (GRT), with distinct i) physical congruence standard, and ii) gravitation dynamics according Hamilton-Lagrange mechanics, while iii) retaining empirical indistinguishability with GRT. In this scalar model the congruence standards have been expressed as gravitationally modified Lorentz Transformations (Broekaert 2002). The first type of these transformations relate quantities observed by gravitationally 'affected' (natural geometry) and 'unaffected' (coordinate geometry) observers and explicitly reveal a spatially variable speed of light (VSL). The second type shunts the unaffected perspective and relates affected observers, recovering i) the invariance of the locally observed velocity of light, and ii) the local Minkowski metric (Broekaert 2003). In the case of a static gravitation field the model retrieves the phenomenology implied by the Schwarzschild metric. The case with proper source kinematics is now described by introduction of a 'sweep velocity' field w: The model then provides a hamiltonian description for particles and photons in full accordance with the first Post-Newtonian approximation of GRT (Weinberg 1972, Will 1993).Comment: v1: 11 pages, GR17 conf. paper, Dublin 2004, v2: WEP issue solved, section on acceleration transformation added, text improved, more references, same results, v3: typos removed, footnotes, added and references updated, v4: appendix added, improved tex

    Repeated successful surgical rescues of early and delayed multiple ruptures of ventricular septum, right ventricle and aneurysmal left ventricle following massive biventricular infarction

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    A 58 year old man underwent 6 surgical interventions for various complications of massive biventricular myocardial infarction over a period of 2 years following acute occlusion of a possibly "hyperdominant" left anterior descending coronary artery. These included concomitant repair of apicoanterior post-infarction VSD and right ventricular free wall rupture, repeat repair of recurrent VSD following inferoposterior extension of VSD in the infarcted septum 5 weeks later, repair of delayed right ventricular free wall rupture 4 weeks subsequently, repair of a bleeding left ventricular aneurysm eroding through left chest wall 16 months thereafter, repair of right upper lobe lung tear causing massive anterior mediastinal haemorrhage, mimicking yet another cardiac rupture, 2 months later, followed, at the same admission, 2 weeks later, by sternal reconstruction for dehisced and infected sternum using pedicled myocutaneous latissimus dorsi flap. 5 years after the latissimus myoplasty, the patient remains in NYHA class 1 and is leading a normal life

    Pathways to child and adolescent psychiatric clinics: a multilevel study of the significance of ethnicity and neighbourhood social characteristics on source of referral

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    <p>Abstract</p> <p>Background</p> <p>In the Swedish society, as in many other societies, many children and adolescents with mental health problems do not receive the help they need. As the Swedish society becomes increasingly multicultural, and as ethnic and economic residential segregation become more pronounced, this study utilises ethnicity and neighbourhood context to examine referral pathways to child and adolescent psychiatric (CAP) clinics.</p> <p>Methods</p> <p>The analysis examines four different sources of referrals: family referrals, social/legal agency referrals, school referrals and health/mental health referrals. The referrals of 2054 children aged 11-19 from the Stockholm Child-Psychiatric Database were studied using multilevel logistic regression analyses.</p> <p>Results</p> <p>Results indicate that ethnicity played an important role in how children and adolescents were referred to CAP-clinics. Family referrals were more common among children and adolescents with a Swedish background than among those with an immigrant background. Referrals by social/legal agencies were more common among children and adolescents with African and Asian backgrounds. Children with Asian or South American backgrounds were more likely to have been referred by schools or by the health/mental health care sector. A significant neighbourhood effect was found in relation to family referrals. Children and adolescents from neighbourhoods with low levels of socioeconomic deprivation were more likely to be referred to CAP-clinics by their families in comparison to children from other neighbourhoods. Such differences were not found in relation in relation to the other sources of referral.</p> <p>Conclusions</p> <p>This article reports findings that can be an important first step toward increasing knowledge on reasons behind differential referral rates and uptake of psychiatric care in an ethnically diverse Swedish sample. These findings have implications for the design and evaluation of community mental health outreach programs and should be considered when developing measures and strategies intended to reach and help children with mental health problems. This might involve providing information about the availability and accessibility of health care for children and adolescents with mental health problems to families in certain neighbourhoods and with different ethnic backgrounds.</p

    Multi-Organ Expression Profiling Uncovers a Gene Module in Coronary Artery Disease Involving Transendothelial Migration of Leukocytes and LIM Domain Binding 2: The Stockholm Atherosclerosis Gene Expression (STAGE) Study

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    Environmental exposures filtered through the genetic make-up of each individual alter the transcriptional repertoire in organs central to metabolic homeostasis, thereby affecting arterial lipid accumulation, inflammation, and the development of coronary artery disease (CAD). The primary aim of the Stockholm Atherosclerosis Gene Expression (STAGE) study was to determine whether there are functionally associated genes (rather than individual genes) important for CAD development. To this end, two-way clustering was used on 278 transcriptional profiles of liver, skeletal muscle, and visceral fat (n = 66/tissue) and atherosclerotic and unaffected arterial wall (n = 40/tissue) isolated from CAD patients during coronary artery bypass surgery. The first step, across all mRNA signals (n = 15,042/12,621 RefSeqs/genes) in each tissue, resulted in a total of 60 tissue clusters (n = 3958 genes). In the second step (performed within tissue clusters), one atherosclerotic lesion (n = 49/48) and one visceral fat (n = 59) cluster segregated the patients into two groups that differed in the extent of coronary stenosis (P = 0.008 and P = 0.00015). The associations of these clusters with coronary atherosclerosis were validated by analyzing carotid atherosclerosis expression profiles. Remarkably, in one cluster (n = 55/54) relating to carotid stenosis (P = 0.04), 27 genes in the two clusters relating to coronary stenosis were confirmed (n = 16/17, P<10−27and−30). Genes in the transendothelial migration of leukocytes (TEML) pathway were overrepresented in all three clusters, referred to as the atherosclerosis module (A-module). In a second validation step, using three independent cohorts, the A-module was found to be genetically enriched with CAD risk by 1.8-fold (P<0.004). The transcription co-factor LIM domain binding 2 (LDB2) was identified as a potential high-hierarchy regulator of the A-module, a notion supported by subnetwork analysis, by cellular and lesion expression of LDB2, and by the expression of 13 TEML genes in Ldb2–deficient arterial wall. Thus, the A-module appears to be important for atherosclerosis development and, together with LDB2, merits further attention in CAD research
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