Meta-analysis of open versus endovascular repair for ruptured descending thoracic aortic aneurysm

IntroductionRuptured descending thoracic aortic aneurysm (rDTAA) is associated with high mortality rates. Data supporting endovascular thoracic aortic aneurysm repair (TEVAR) to reduce mortality compared with open repair are limited to small series. We investigated published reports for contemporary outcomes of open and endovascular repair of rDTAA.MethodsWe systematically reviewed all studies describing the outcomes of rDTAA treated with open repair or TEVAR since 1995 using MEDLINE, Cochrane Library CENTRAL, and Excerpta Medica Database (EMBASE) databases. Case reports or studies published before 1995 were excluded. All articles were critically appraised for relevance, validity, and availability of data regarding treatment outcomes. All data were systematically pooled, and meta-analyses were performed to investigate 30-day mortality, myocardial infarction, stroke, and paraplegia rates after both types of repair.ResultsOriginal data of 224 patients (70% male) with rDTAA were identified: 143 (64%) were treated with TEVAR and 81 (36%) with open repair. Mean age was 70 ± 5.6 years. The 30-day mortality was 19% for patients treated with TEVAR for rDTAA compared 33% for patients treated with open repair, which was significant (odds ratio [OR], 2.15, P = .016). The 30-day occurrence rates of myocardial infarction (11.1% vs 3.5%; OR, 3.70, P < .05), stroke (10.2% vs 4.1%; OR, 2.67; P = .117), and paraplegia (5.5% vs 3.1%; OR, 1.83; P = .405) were increased after open repair vs TEVAR, but this failed to reach statistical significance for stroke and paraplegia. Five additional patients in the TEVAR group died of aneurysm-related causes after 30 days, during a median follow-up of 17 ± 10 months. Follow-up data after open repair were insufficient. The estimated aneurysm-related survival at 3 years after TEVAR was 70.6%.ConclusionEndovascular repair of rDTAA is associated with a significantly lower 30-day mortality rate compared with open surgical repair. TEVAR was associated with a considerable number of aneurysm-related deaths during follow-up

Monitoring Cl- movement in single cells exposed to hypotonic solution

Self-referencing ion--selective electrodes (ISEs), made with Chloride Ionophore I-Cocktail A (Fluka), were positioned 1-3 microm from human embryonic kidney cells (tsA201a) and used to record chloride flux during a sustained hyposmotic challenge. The ISE response was close to Nernstian when comparing potentials (VN) measured in 100 and 10 mM NaCl (deltaVN = 57 +/- 2 mV), but was slightly greater than ideal when comparing 1 and 10 mM NaCl (deltaVN = 70 +/- 3 mV). The response was also linear in the presence of 1 mM glutamate, gluconate, or acetate, 10 microM tamoxifen, or 0.1, 1, or 10 mM HEPES at pH 7.0. The ISE was approximately 3 orders of magnitude more selective for Cl- over glutamate or gluconate but less than 2 orders of magnitude move selective for Clover bicarbonate, acetate, citrate or thiosulfate. As a result this ISE is best described as an anion sensor. The ISE was 'poisoned' by 50 microM 5-nitro-2-(3phenylpropyl-amino)-benzoic acid (NPPB), but not by tamoxifen. An outward anion efflux was recorded from cells challenged with hypotonic (250 +/- 5 mOsm) solution. The increase in efflux peaked 7-8 min before decreasing, consistent with regulatory volume decreases observed in separate experiments using a similar osmotic protocol. This anion efflux was blocked by 10 microM tamoxifen. These results establish the feasibility of using the modulation of electrochemical, anion-selective, electrodes to monitor anions and, in this case, chloride movement during volume regulatory events. The approach provides a real-time measure of anion movement during regulated volume decrease at the single-cell leve

Open surgery versus endovascular repair of ruptured thoracic aortic aneurysms

Background: Ruptured descending thoracic aortic aneurysm (rDTAA) is a cardiovascular catastrophe, associated with high morbidity and mortality, which can be managed either by open surgery or thoracic endovascular aortic repair (TEVAR). The purpose of this study is to retrospectively compare the mortality, stroke, and paraplegia rates after open surgery and TEVAR for the management of rDTAA. Methods: Patients with rDTAA treated with TEVAR or open surgery between 1995 and 2010 at seven institutions were identified and included for analysis. The outcomes between both treatment groups were compared; the primary end point of the study was a composite end point of death, permanent paraplegia, and/or stroke within 30 days after the intervention. Multivariate logistic regression analysis was used to identify risk factors for the primary end point. Results: A total of 161 patients with rDTAA were included, of which 92 were treated with TEVAR and 69 with open surgery. The composite outcome of death, stroke, or permanent paraplegia occurred in 36.2% of the open repair group, compared with 21.7% of the TEVAR group (odds ratio [OR], 0.49; 95% confidence interval [CI], .24-.97; P = .044). The 30-day mortality was 24.6% after open surgery compared with 17.4% after TEVAR (OR, 0.64; 95% CI, .30-1.39; P = .260). Risk factors for the composite end point of death, permanent paraplegia, and/or stroke in multivariate analysis were increasing age (OR, 1.04; 95% CI, 1.01-1.08; P = .036) and hypovolemic shock (OR, 2.47; 95% CI, 1.09-5.60; P = .030), while TEVAR was associated with a significantly lower risk of the composite end point (OR, 0.44; 95% CI, .20-.95; P = .039). The aneurysm-related survival of patients treated with open repair was 64.3% at 4 years, compared with 75.2% for patients treated with TEVAR (P = .191). Conclusions: Endovascular repair of rDTAA is associated with a lower risk of a composite of death, stroke, and paraplegia, compared with traditional open surgery. In rDTAA patients, endovascular management appears the preferred treatment when this method is feasible

LDA+DMFT approach to ordering phenomena and the structural stability of correlated materials

Materials with correlated electrons often respond very strongly to external or internal influences, leading to instabilities and states of matter with broken symmetry. This behavior can be studied theoretically either by evaluating the linear response characteristics, or by simulating the ordered phases of the materials under investigation. We developed the necessary tools within the dynamical mean-field theory (DMFT) to search for electronic instabilities in materials close to spin-state crossovers and to analyze the properties of the corresponding ordered states. This investigation, motivated by the physics of LaCoO3, led to a discovery of condensation of spinful excitons in the two-orbital Hubbard model with a surprisingly rich phase diagram. The results are reviewed in the first part of the article. Electronic correlations can also be the driving force behind structural transformations of materials. To be able to investigate correlation-induced phase instabilities we developed and implemented a formalism for the computation of total energies and forces within a fully charge self-consistent combination of density functional theory and DMFT. Applications of this scheme to the study of structural instabilities of selected correlated electron materials such as Fe and FeSe are reviewed in the second part of the paper