Endovascular Treatment for Chronic Arteriovenous Fistula Between Renal Artery and Inferior Vena Cava: Image in Vascular Surgery

Arteriovenous fistula involving renal artery and inferior vena cava are rare. We report the case of a 47-year-old woman with a chronic arteriovenous fistula between right renal artery and inferior vena cava due to a penetrating trauma. Another finding was a vena cava aneurysm caused by the fistula. The patient was successfully treated with a covered stent in the renal artery. Diagnosis and postoperative control have been documented with CT scan. Endovascular techniques may be effective and minimally invasive option for treatment and renal preservation in renal-cava arteriovenous fistulae.

Ticagrelor vs. clopidogrel in patients with acute coronary syndromes and diabetes: a substudy from the PLATelet inhibition and patient Outcomes (PLATO) trial

Patients with diabetes mellitus (DM) have high platelet reactivity and are at increased risk of ischaemic events and bleeding post-acute coronary syndromes (ACS). In the PLATelet inhibition and patient Outcomes (PLATO) trial, ticagrelor reduced the primary composite endpoint of cardiovascular death, myocardial infarction, or stroke, but with similar rates of major bleeding compared with clopidogrel. We aimed to investigate the outcome with ticagrelor vs. clopidogrel in patients with DM or poor glycaemic control. We analysed patients with pre-existing DM (n = 4662), including 1036 patients on insulin, those without DM (n = 13 951), and subgroups based on admission levels of haemoglobin A1c (HbA1c; n = 15 150). In patients with DM, the reduction in the primary composite endpoint (HR: 0.88, 95% CI: 0.76-1.03), all-cause mortality (HR: 0.82, 95% CI: 0.66-1.01), and stent thrombosis (HR: 0.65, 95% CI: 0.36-1.17) with no increase in major bleeding (HR: 0.95, 95% CI: 0.81-1.12) with ticagrelor was consistent with the overall cohort and without significant diabetes status-by-treatment interactions. There was no heterogeneity between patients with or without ongoing insulin treatment. Ticagrelor reduced the primary endpoint, all-cause mortality, and stent thrombosis in patients with HbA1c above the median (HR: 0.80, 95% CI: 0.70-0.91; HR: 0.78, 95% CI: 0.65-0.93; and HR: 0.62, 95% CI: 0.39-1.00, respectively) with similar bleeding rates (HR: 0.98, 95% CI: 0.86-1.12). Ticagrelor, when compared with clopidogrel, reduced ischaemic events in ACS patients irrespective of diabetic status and glycaemic control, without an increase in major bleeding events.

Azithromycin does not prevent six-month myointimal proliferation but attenuates the transient systemic inflammation occurring after coronary stenting

Stent implantation produces a systemic increase of inflammatory markers that correlates with Chlamydophila pneumoniae infection in atherosclerotic plaque. We performed a clinical intervention study to investigate the effect of antibiotic treatment on 6-month follow-up angiographic minimal luminal diameter after stenting. Ninety patients were randomly assigned to oral azithromycin or placebo in a double-blinded and randomized fashion. Medication was initiated 2 weeks before a pre-scheduled stenting procedure and maintained 12 weeks thereafter. Angiographic outcomes were evaluated by a six-month follow-up angiography and laboratorial parameters were accessed by blood sampling 2 weeks before stenting, within the first 24 h after procedure and additional samples after four weeks and 6 months. Minimal luminal diameter (1.76 +/- A 0.56 mm Vs. 1.70 +/- A 0.86 mm; P = 0.7), restenosis rate, diameter stenosis, late loss, and binary restenosis rates were comparable in placebo and azithromycin group in the 6 months follow-up. Serum levels of C-reactive protein presented a three fold significant increase in the control group one day after stenting but did not change in the azithromycin group (8.5 [3.0;16.4] Vs. 2.9 [1.7;6.6]-median [25;75 percentile] P < 0.01). Azithromycin does not improve late angiographic outcomes but attenuates the elevation of C-reactive protein levels after stenting, indicating an anti-inflammatory effect.

Sintering kinetics of Mo-free cermets

Titanium carbonitride-based cermets are important materials for contemporary cutting tools. Ceramic powders of Ti(CN), TaC, WC were mixed, compacted and heat-treated at high temperatures to form (Ti, W, Ta)(C, N) solid solution, which was then ball-milled to fine powders before being mixed with metallic binder and compacted. Liquid-phase sintering of the samples was carried out in a nitrogen atmosphere at different sintering temperatures and holding times. The microhardness and porosity of the sintered cermets were studied. It is demonstrated that the microhardness increases with sintering temperature, but at the same time, the porosity level also goes up with temperature and time. At the beginning of sintering (zero holding time), the majority of the pores are small (0.1 similar to 1 mu m); during sintering, the larger ports grow at the expense of smaller pores and the resulting pores are all concentrated in the 10 similar to 100 mu m range. The number of larger pores increases with temperature and prolonged holding time, which results in deteriorated properties. (C) 1997 Elsevier Science S.A.

Midterm and long-term results of percutaneous endovascular treatment of venous outflow obstruction after pediatric liver transplantation

PURPOSE: To evaluate retrospectively the midterm and long-term results of percutaneous endovascular treatment of venous outflow obstruction after pediatric liver transplantation. MATERIALS AND METHODS: During a 9-year period, 18 children with obstruction of a hepatic vein (HV) or inferior vena cava (IVC) anastomosis underwent percutaneous transluminal angioplasty (PTA) with balloon dilation or stent placement in case of PTA failure after liver transplantation. Patients` body weights ranged from 7.7 kg to 42.6 kg (mean, 18.8 kg +/- 9). Potential predictors of patency were compared between balloon dilation and stent placement groups. RESULTS: Forty-two procedures were performed (range, 1-11 per patient; mean, 2). Technical and initial clinical success were achieved in all cases. Major complications included one case of pulmonary artery stent embolization and one case of hemothorax. Three children (25%) with HV obstruction were treated with PTA and nine (75%) were treated with stent placement. Three children with IVC obstruction (75%) were treated with PTA and one (25%) was treated with a stent. There were two children with simultaneous obstruction at the HV and IVC; one was treated with PTA and the other with a stent. Cases of isolated HV stenosis have a higher probability of patency with balloon-expandable stent treatment compared with balloon dilation (P < .05). Follow-up time ranged from 7 days to 9 years (mean, 42 months +/- 31), and the primary assisted patency rate was 100% when stent placement was performed among the first three procedures. CONCLUSIONS: In cases of venous outflow obstruction resulting from HV and/or IVC lesions after pediatric liver transplantation, percutaneous endovascular treatment with balloon dilation or stent placement is a safe and effective alternative treatment that results in long-term patency.

Long-term results of the percutaneous transhepatic venoplasty of portal vein stenoses after pediatric liver transplantation

This paper has the objective to evaluate retrospectively the long-term results of transhepatic treatment of PV stenoses after pediatric LT. During an eight-yr period, 15 children with PV stenoses underwent PTA with balloon dilation or stent placement in case of PTA failure after LT. Patients` body weights ranged from 9.3 to 46 kg (mean, 15.5 kg). PV patency was evaluated in the balloon dilation and in the stent placement groups. Technical and clinical successes were achieved in all cases with no complication. Eleven patients (11/15; 73.3%) were successfully treated by single balloon dilation. Four patients (4/15; 26.7%) needed stent placement. One patient was submitted to stent placement during the same procedure because of PTA failure. The other three developed clinical signs of portal hypertension because of PV restenoses two, eight, and twenty-eight months after the first PTA. They had to be submitted to a new procedure with stent placement. The follow-up time ranged from 3 to 8.1 yr (mean, 6.3 yr). In conclusion, transhepatic treatment of PV stenoses after pediatric LT with balloon dilation or stent placement demonstrated to be a safe and effective treatment that results in long-term patency.

Opaque Layer Firing Temperature and Aging Effect on the Flexural Strength of Ceramic Fused to Cobalt-Chromium Alloy

Purpose: To evaluate the effect of the opaque layer firing temperature and mechanical and thermal cycling on the flexural strength of a ceramic fused to commercial cobalt-chromium alloy (Co-Cr). The hypotheses were that higher opaque layer temperatures increase the metal/ceramic bond strength and that aging reduces the bond strength. Materials and Methods: Metallic frameworks (25 x 3 x 0.5 mm(3); ISO 9693) (N = 60) were cast in Co-Cr and airborne-particle abraded (Al(2)O(3): 150 mu m) at the central area of the frameworks (8 x 3 mm(2)) and divided into three groups (N = 20), according to the opaque layer firing temperature: Gr1 (control)-900 degrees C; Gr2-950 degrees C; Gr3-1000 degrees C. The opaque ceramic (Opaque, Vita Zahnfabrick, Bad Sackingen, Germany) was applied, and the glass ceramic (Vita Omega 900, Vita Zahnfabrick) was fired onto it (thickness: 1 mm). While half the specimens from each group were randomly tested without aging (water storage: 37 degrees C/24 hours), the other half were mechanically loaded (20,000 cycles; 50 N load; distilled water at 37 degrees C) and thermocycled (3000 cycles; 5 degrees C to 55 degrees C, dwell time: 30 seconds). After the flexural strength test, failure types were noted. The data were analyzed using 2-way ANOVA and Tukey`s test (alpha = 0.05). Results: Gr2 (19.41 +/- 5.5 N) and Gr3 (20.6 +/- 5 N) presented higher values than Gr1 (13.3 +/- 1.6 N) (p = 0.001). Mechanical and thermal cycling did not significantly influence the mean flexural strength values (p > 0.05). Increasing the opaque layer firing temperature improved the flexural bond strength values (p < 0.05). The hypotheses were partially accepted. Conclusion: Increasing of the opaque layer firing temperature improved the flexural bond strength between ceramic fused to Co-Cr alloy.

Use of Inverted Fluoroscope`s C-arm During Endoscopic Treatment of Urinary Tract Obstruction in Pregnancy: A Practicable Solution to Cut Radiation

OBJECTIVES To describe the use of pulsed fluoroscopic guidance, to perform endoscopic procedures in pregnant women, by inverting the fluoroscope`s c-arm using a lead thyroid collar to shield the fetus from the direct X-ray beam. The use of radiation during treatment of pregnant patients with urolithiasis remains a recurring dilemma. METHODS Between May 2006 and December 2008, endoscopic treatment due to ureteral stones was attempted in 8 pregnant women. In all cases, we use an inverted fluoroscope`s c-arm during endoscopic treatment associated with 2 lead neck thyroid collars to shield the uterus, protecting the fetus from direct radiation. Indication for treatment was symptomatic ureteral stones unresponsive to medical treatment in 7 and persistent fever in 1. RESULTS Mean ureteral stone size was 8.1 +/- 4.8 mm, located in the left ureter in 5 (62.5%) cases. Three (37.5%) patients had stone located in the upper ureter, 2 (25%) in the middle ureter, and 3 (37.5) in the distal ureter. In 6 cases, ureteral stones were treated using the semi-rigid ureteroscope, whereas in 1 case a flexible ureteroscope was needed. One woman was treated with insertion of a double-J stent due to associated urinary infection. No women has early delivery related to the endoscopic procedure, and all neonates were perfectly normal. CONCLUSIONS We present a technique for endoscopic procedures in pregnant women inverting the fluoroscope`s c-arm and protecting the fetus from the direct X-ray beam. This practical approach should be specially considered when no portable ultrasound and radiologic assistance in available in the operating room. UROLOGY 75: 1505-1508, 2010. (c) 2010 Published by Elsevier Inc.

Hepatic Veins and Inferior Vena Cava Thrombosis in a Child Treated by Transjugular Intrahepatic Portosystemic Shunt

We report the case of a 9-year-old boy with portal hypertension, due to Budd-Chiari syndrome, and retrohepatic inferior vena cava thrombosis, submitted to a transjugular intrahepatic portosystemic shunt (TIPS) by connecting the suprahepatic segment of the inferior vena cava directly to the portal vein. After 3 months, the withdrawal of anticoagulants promoted the thrombosis of the TIPS. At TIPS revision, thrombosis of the TIPS and the main portal vein and clots at the splenic and the superior mesenteric veins were found. Successful angiography treatment was performed by thrombolysis and balloon angioplasty of a severe stenosis at the distal edge of the stent.

Prognostic heterogeneity among patients with chronic stable coronary disease: determinants of long-term mortality after treatment with percutaneous intervention

Aims: To evaluate the risk and predictors of death in a large population of patients with stable coronary disease treated with percutaneous intervention. Methods and results: The study population comprised 1,276 patients with chronic angina or silent ischaemia who underwent elective coronary angioplasty. Baseline and in-hospital mortality data were prospectively collected for all patients during the index hospitalisation. Post-discharge outcome was assessed at out-patient clinic, by review of the patients` records, or direct phone contact. Deaths were classified as cardiac and non-cardiac. Age, peripheral arterial disease, congestive heart failure with NYHA class Ill, triple-vessel disease, and procedural success (i.e. angiographic success for all lesions in the absence of pen-procedural infarction) remained as multivariate independent predictors of death. For the entire population 4-year cumulative all-cause and cardiac mortality were respectively 5.4% and 4.1%. Four-year mortality for patients without any multivariate predictor was 2.4%, while for patients with two or more predictors the death rate was 16.3% after four years. Conclusions: Patients with stable coronary disease undergoing percutaneous treatment have an overall low mortality rate after four years. Nevertheless, stable patients comprise a heterogeneous population in terms of risk profile, ranging from patients at very low risk of late death to individuals with a poor long-term prognosis.

Laparoscopic resection of uncinate process of the pancreas

Solid pseudopapillary neoplasm of the pancreas is an uncommon but distinctive pancreatic neoplasm with low metastatic potential [1]. Therefore, whenever feasible, an organ-preserving operation should be performed. As previously reported, women with solid pseudopapillary neoplasm of the pancreas may be best treated by more conservative procedures [2]. Recently, laparoscopic pancreatic resections became more common and are being performed in highly specialized centers. There are only six cases of laparoscopic resection for solid pseudopapillary neoplasm of pancreas published in the English literature and, to our knowledge, laparoscopic resection of uncinate process of the pancreas has never been reported [3-6]. This video demonstrates the technical aspects of a totally laparoscopic resection of the uncinate process of the pancreas in a patient with solid pseudopapillary neoplasm. A 26-year-old woman with a 4-cm solid pseudopapillary pancreatic neoplasm was referred for surgical treatment. According to preoperative echoendoscopy, there was a safe margin between neoplasm and main pancreatic duct. The patient was placed in supine position with the surgeon standing between her legs. Four trocars, one 10-mm and three 5-mm, were used. At inspection, the inferior vena cava, transverse colon, duodenum, and pancreas are clearly identified. A Kocher maneuver was performed with complete exposure of pancreatic head and uncinate process. The uncinate process was dissected from the superior mesenteric vein and venous branches were divided between metallic clips or by use of laparoscopic coagulation shears (LCS; Ethicon Endo Surgery Industries, Cincinnati, OH, USA). Blood supply of the duodenum was preserved by ligature of small pancreatic branches from inferior pancreatoduodenal artery. Transection of pancreatic parenchyma was performed using laparoscopic coagulation shears, which is an effective tool for cutting the pancreas [7, 8]. Surgical specimen was removed through a suprapubic incision inside a retrieval bag. A hemostatic absorbable tissue (Surgicel; Ethicon Inc., Cincinnati, OH) was placed in the cutting pancreatic surface, and one round 19F Blake abdominal drain (Ethicon) was left in place. Operative time was 180 minutes and blood loss estimated in 40 ml with no blood transfusion. Hospital stay was 4 days. The patient did not have postoperative pancreatitis or pancreatic leakage, and the abdominal drain was removed on the tenth postoperative day. Final pathology confirmed the diagnosis of solid pseudopapillary neoplasm of pancreas with free surgical margins. The patient was well and asymptomatic 2 months after the procedure. Laparoscopic resection of uncinate process of the pancreas is safe and feasible and should be considered for patients suffering from pancreatic neoplasms.

Laparoscopic Enucleation of Liver Tumors. Corkscrew Technique Revisited

Background: Enucleation of small lesions located near the hepatic surface can be achieved with low morbidity and mortality. This article describes a simple laparoscopic technique for enucleation of liver tumors. Methods: After inspection and intraoperative ultrasonography, Glisson`s capsule is marked with eletrocautery 2 cm away from the tumor margin. Ultrasonography is used to ascertain surgical margin right before liver transection. Hemihepatic ischemia is applied and marked area is anchored by stitches. The suture is held together by metallic clips and upward traction is performed, facilitating the transection of the parenchyma and correct identification of vascular and biliary structures. Results: This technique has been successfully employed in six consecutive patients. There were four men and two women, mean age 50.3 years. Four patients underwent liver resection for malignant disease and two for benign liver neoplasm. Pathologic surgical margins were free in all cases and mean hospital stay was 2 days. No postoperative mortality was observed. Conclusion: This technique may facilitate laparoscopic nonanatomical liver resection and reduce risk of positive surgical margins. It is also useful in combination with anatomical laparoscopic liver resections such as right or left hemihepatectomies in patients with bilateral liver tumors as occurred in one of our patients.

Cost-Effectiveness of Palliation of Unresectable Esophageal Cancer

Introduction Different modalities of palliation for obstructive symptoms in patients with unresectable esophageal cancer (EC) exist. However, these therapeutic alternatives have significant differences in costs and effectiveness. Methods A Markov model was designed to compare the cost-effectiveness (CE) of self-expandable stent (SES), brachytherapy and laser in the palliation of unresectable EC. Patients were assigned to one of the strategies, and the improvement in swallowing function was compared given the treatment efficacy, probability of survival, and risks of complications associated to each strategy. Probabilities and parameters for distribution were based on a 9-month time frame. Results Under the base-case scenario, laser has the lowest CE ratio, followed by brachytherapy at an incremental cost-effectiveness ratio (ICER) of $4,400.00, and SES is a dominated strategy. In the probabilistic analysis, laser is the strategy with the highest probability of cost-effectiveness for willingness to pay (WTP) values lower than $3,201 and brachytherapy for all WTP yielding a positive net health benefit (NHB) (threshold $4,440). The highest probability of cost-effectiveness for brachytherapy is 96%, and consequently, selection of suboptimal strategies can lead to opportunity losses for the US health system, ranging from US$ 4.32 to US$ 38.09 million dollars over the next 5-20 years. Conclusion Conditional to the WTP and current US Medicare costs, palliation of unresectable esophageal cancers with brachytherapy provides the largest amount of NHB and is the strategy with the highest probability of CE. However, some level of uncertainly remains, and wrong decisions will be made until further knowledge is acquired.

Differences in the inflammatory response between patients with and those without diabetes mellitus after coronary stenting

Background: Patients with diabetes mellitus who undergo coronary stenting are at increased risk of restenosis. It is known that inflammation plays a crucial role in restenosis. Objective: We assessed the inflammatory response to elective coronary stent implantation (CSI) in stable diabetic and nondiabetic patients. Methods: C-reactive protein (CRP), soluble (s) P-selectin, and soluble intercellular adhesion molecule (sICAM)-1 plasma levels were determined in diabetic (n = 51) and nondiabetic (n = 56) patients before and 48 hours and 4 weeks after bare metal stenting (BMS). Results: Diabetic patients presented significantly higher inflammatory marker levels before and after CSI. Nonetheless, diabetic and nondiabetic patients had postintervention peak of markers attained within 48 hours. At baseline, diabetic and nondiabetic patients presented CRP levels of 5.0 +/- 20.1 (P <= 0.04) and 3.8 +/- 9.4 mu g/ml and, at 48 hours postintervention, 22.0 +/- 20.2 (P = 0.001; P = 0.002) and 12.6 +/- 11.3 (P <= 0.0001) mu g/ml. Regarding sP-selectin, diabetic and nondiabetic patients obtained levels of, at baseline, 182 +/- 118 (P <= 0.04) and 105 +/- 48 ng/ml and, at 48 hours, 455 +/- 290 (P = 0.001; P <= 0.01) and 215 +/- 120 (P <= 0.04) ng/ml. For diabetic and nondiabetic patients, sICAM-1 levels were, at baseline, 248 +/- 98 (P <= 0.04) and 199 +/- 94 ng/ml and, at 48 hours, 601 +/- 201 (P = 0.001; P <= 0.01) and 283 +/- 220 (P = 0.001) ng/ml. At 4 weeks, for all patients, markers returned to preprocedural levels: versus before PCI: *P = 0.001, P <= 0.0001; versus nondiabetic patients: ^#P <= 0.04, P = 0.002, ^UpsilonP <= 0.01. Conclusions: Diabetic and nondiabetic patients exhibited a temporal inflammatory response after an elective BMS. However, diabetic patients present higher preprocedural levels of CRP, sP-selectin, and sICAM-1 and reveal a further exacerbated inflammatory response after intervention. The differences in inflammatory response may have implications in restenosis within these two sets of patients.

Influence of thermal and mechanical cycling on the flexural strength of ceramics with titanium or gold alloy frameworks

Objectives. The aim of this study was to evaluate the effect of thermal and mechanical cycling alone or in combination, on the flexural strength of ceramic and metallic frameworks cast in gold alloy or titanium. Methods. Metallic frameworks (25 mm x 3 mm x 0.5 mm) (N = 96) cast in gold alloy or commercial pure titanium (Ti cp) were obtained using acrylic templates. They were airborne particle-abraded with 150 mu m aluminum oxide at the central area of the frameworks (8 mm x 3 mm). Bonding agent and opaque were applied on the particle-abraded surfaces and the corresponding ceramic for each metal was fired onto them. The thickness of the ceramic layer was standardized by positioning the frameworks in a metallic template (height: I mm). The specimens from each ceramic-metal combination (N = 96, n = 12 per group) were randomly assigned into four experimental fatigue conditions, namely water storage at 37 degrees C for 24 h (control group), thermal cycling (3000 cycles, between 4 and 55 degrees C, dwell time: 10 s), mechanical cycling (20,000 cycles under 10 N load, immersion in distilled water at 37 degrees C) and, thermal and mechanical cycling. A flexural strength test was performed in a universal testing machine (crosshead speed: 1.5 mm/min). Data were statistically analyzed using two-way ANOVA and Tukey`s test (alpha = 0.05). Results. The mean flexural strength values for the ceramic-gold alloy combination (55 +/- 7.2MPa) were significantly higher than those of the ceramic-Ti cp combination (32 +/- 6.7 MPa) regardless of the fatigue conditions performed (p < 0.05). Mechanical and thermo-mechanical fatigue decreased the flexural strength results significantly for both ceramic-gold alloy (52 +/- 6.6 and 53 +/- 5.6 MPa, respectively) and ceramic-Ti cp combinations (29 +/- 6.8 and 29 +/- 6.8 MPa, respectively) compared to the control group (58 +/- 7.8 and 39 SA MPa, for gold and Ti cp, respectively) (p < 0.05) (Tukey`s test). While ceramic-Ti cp combinations failed adhesively at the metal-opaque interface, gold alloy frameworks exhibited a residue of ceramic material on the surface in all experimental groups. Significance. Mechanical and thermo-mechanical fatigue conditions decreased the flexural strength values for both ceramic-gold alloy and ceramic-Ti cp combinations with the results being significantly lower for the latter in all experimental conditions. (C) 2007 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.