Percutaneous endoluminal grafts for AAA repair in the catheterization laboratory

Background Percutaneous abdominal aortic aneurysm(AAA) repair has been previously described using the "preclose"technique and general endotrachial anesthesia (GA).     

Double beam and detector γ-radiation attenuation gauge for studying bubble phenomena in gas-solid fluidized beds

In this paper the technique of cross-correlating the void fractions derived from the transmission signals of two γ-sources is used for the non-intrusive study of bubble phenomena in gas-solid fluidized beds. Special attention is given to the optimization of this method with respect to the statistical uncertainty inherent to radioactive decay. Experiments in a 40 cm gas-solid fluidized bed illustrate that bubble velocity distributions can be obtained.     

Combined endovascular and surgical treatment of infected carotid-carotid bypass graft.

PURPOSE: To present a complex case involving an infected carotid-carotid bypass graft that was successfully treated with a stent-graft and subsequent surgical removal of the infected graft. CASE REPORT: A 75-year-old woman presented with persistent purulent drainage of an infected and exposed carotid-carotid prosthetic bypass graft. Wound cultures revealed methicillin-resistant Staphylococcus aureus. She was treated with appropriate intravenous antibiotic therapy without improvement in wound drainage. Because of her comorbid conditions, a decision was made to pursue endovascular revascularization of her left and right common carotid arteries (CCA), with subsequent surgical removal of the infected prosthetic graft. The patient underwent balloon angioplasty; a 7x18-mm Omnilink stent was deployed in the innominate artery and a 7x18-mm Herculink stent in the ostial left CCA. During the same procedure, the carotid-carotid bypass graft was excluded with deployment of an 8x50-mm Viabahn stent-graft in the right CCA. Several days later, the infected and now thrombosed carotid-carotid bypass graft was surgically removed, and an area of adjacent muscle was used to patch the previously excluded connection of the bypass from the right CCA. A saphenous vein patch was used to repair the defect in the left CCA. Her postoperative course was uneventful. At 1 year, the clinical and duplex examinations revealed satisfactory wound healing and patent left and right CCAs. CONCLUSION: This case indicates that a combined endovascular and surgical approach may be a safe and effective option in the treatment of carotid-carotid bypass graft infection.     

Treatment of End-Stage Renal Disease in Central and Eastern Europe: Overview of Current Status and Future Needs

The situation of end-stage renal disease (ESRD) patients in central and eastern Europe was very poor for many years during the so called socialistic era. Economical and political liberation resulted in the significant growth of renal replacement facilities in this region. The number of hemodialysis units increased significantly (56%) during the period 1990–1996, and the number of patients treated with this modality has risen by 75%. More dramatic progress was achieved in peritoneal dialysis. The number of units performing this method of renal replacement therapy (RTT) increased by 277% and the number of patients by more than 300%. Not only quantitative but also qualitative changes were observed. More modern hemodialysis machines installed in the vast majority of units allow for the performance of bicarbonate dialysis, controlled ultrafiltration, and sodium profile modeling. Also, a wider choice of biocompatible dialyzers has become available during the last few years. The number of centers performing renal transplantation has increased significantly, but the number of renal transplants has not followed this progress. Despite all the progress, further development of all RRT methods is necessary to achieve acceptance rates comparable to those observed in developed countries.     

Increased venous proinflammatory gene expression and intimal hyperplasia in an aorto-caval fistula model in the rat

We hypothesized that the venous limb of an arteriovenous (AV) fistula would evince up-regulation of genes relevant to vascular remodeling along with neointimal hyperplasia and relevant histological changes. Using the aorto-caval model of an AV fistula model in the rat, we demonstrate marked up-regulation in such proinflammatory genes as monocyte chemoattractant protein-1, plasminogen activator inhibitor-1, and endothelin-1, 2 weeks after the creation of the fistula. Neointimal hyperplasia occurred in variable degrees by 5 weeks after establishing the fistula, and by 16 weeks, such neointimal hyperplasia was progressive and pronounced; at this time point, abundant extracellular matrix was also observed. Smooth muscle cells were present in the hyperplastic neointima as evidenced by staining for alpha-smooth muscle actin; ultrastructurally, smooth muscle cells with a synthetic as well as a contractile phenotype were readily observed. Accumulation of extracellular matrix in the model at 16 weeks was accompanied by increased expression of transforming growth factor-beta1 mRNA, the latter finding contrasting with the suppression of transforming growth factor-beta1 mRNA observed in this model at 2 weeks. In summary, we describe marked up-regulation in proinflammatory genes and progressive neointimal formation in the venous vasculature in an AV fistula model in the rat. We suggest that such alteration in gene expression and histological injury, in conjunction with the relative simplicity of this model, offer a new approach in the study of such timely biological and clinically relevant phenomena as differential gene expression in response to hemodynamic forces, processes involved in vascular remodeling, mechanisms of injury in venous bypass grafts, and mechanisms of dysfunction of AV fistulae used in hemodialysis.     

Treatment of malignant gliomas in adults with BCNU plus metronidazole

Summary Twenty-six adult patients with astrocytomas were treated with BCNU (1,3-bis(2-chloroethyl)-1-nitrosourea) 180–240 mg/m² 1.V. every 6–9 weeks, with metronidazole 1.5 g/m² p. o. 12 h and 1 h before BCNU and again 6 h and 24 h after BCNU. Of twenty-two evaluable patients, 9 (41%) responded with evidence of reduced tumor size on CT scan, 3 (14%) stabilized and 10 (45%) failed. Patients with no prior chemotherapy or radiotherapy, good performance. status, low grade tumors, and age 50 years had the highest response rates, although differences were not statistically significant. Median survival and duration of response have not been reached with a median follow-up time of ten months. Hematological toxicity was dose-limiting and was probably not augmented by the metronidazole. There was one death from infection that was possibly drug-related. Gastrointestinal toxicity was substantial, and was probably increased by the metronidazole.While the combination of BCNU and metronidazole were tolerable, the response rate seen was no higher than that noted for BCNU alone, and further studies using this dose-schedule are not recommended in astrocytomas.Presented at the 13th International Congress of Chemotherapy, Vienna Austria, August 1983.     

Aneurysm of the membranous septum causing outflow obstruction of the venous ventricle in corrected transposition of the great arteries

A 58 year-old man with clinical and hemodynamic evidence of subpulmonic stenosis was admitted to our hospital. Angiography revealed corrected transposition of the great arteries and an aneurysm of membranous ventricular septum (AVS) that protruded into the venous outflow tract, causing severe subpulmonic obstruction during systole. The diagnosis was confirmed at surgery, and successful repair of the aneurysm was performed. This was an unusual case because the AVS caused such severe obstruction that the venous ventricular pressure was elevated to a value equal to the systemic level.     

TAVI: How to best predict postprocedural outcomes?

• Baseline risk scores for TAVI patients, including STS and EuroSCORE, might not predict long‐term outcomes.
• Including postprocedural data might improve risk stratification.
• The ACEF‐7 risk score includes the lowest creatinine clearance in the first 7 postprocedural days and appears to be a good predictor of worse long‐term outcomes.

     

HN-10200 causes endothelium-independent relaxations in isolated canine arteries

Summary HN-10200, a nonselective inhibitor of phosphodiesterase, has positive inotropic and vasodilator activity. The present study was designed to determine the role of endotheliumin in causing relaxation to HN-10200 in isolated canine femoral and basilar arteries. Rings with and without endothelium were suspended for isometric tension recording in Krebs-Ringer bicarbonate solution bubbled with 94% O₂, 6% CO₂ (t=37°C; pH=7.4). HN-10200 and another nonselective phosphodiesterase inhibitor, 3-isobutyl-1-methyl-xanthine (IBMX), caused similar concentration-dependent relaxations in femoral arteries with and without endothelium. In femoral arteries without endothelium, HN-10200 and IBMX significantly augmented relaxations to prostacyclin, but did not affect relaxations to a nitric oxide donor 3-morpholinosydnonimine (SIN-1) or endothelium-derived relaxing factor (EDRF) released by bradykinin. In basilar arteries, relaxations to HN-10200 were augmented by the removal of endothelium, whereas relaxations to IBMX were not affected. Relaxations to prostacyclin, SIN-1, and EDRF were not affected by the presence of phosphodiesterase inhibitors. The results of the present study suggest that HN-10200 causes endothelium-independent relaxations. In addition, it may augment relaxations to prostacyclin but does not affect relaxations to EDRF.     

Peripheral artery disease: How do genes and pharmacology interplay?

• In patients with peripheral artery disease, high on‐treatment platelet reactivity (HoTPR) might be associated with worse outcomes for those taking clopidogrel, but not for those taking aspirin.
• Certain genetic polymorphisms might account for HoTPR.
• Current literature supports the importance of antiplatelet therapy in treating patients with PAD with clopidogrel, aspirin, or both.