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Background

Chronic limb-threatening ischemia (CLTI), defined as ischemic rest pain or tissue loss secondary to arterial insufficiency, is caused by multilevel arterial disease with frequent, severe infrageniculate disease. The rise in CLTI is in part the result of increasing worldwide prevalence of diabetes, renal insufficiency, and advanced aging of the population. The aim of this study was to compare a bypass-first with an endovascular-first revascularization strategy in patients with CLTI due to infrageniculate arterial disease.

Methods

We reviewed the American College of Surgeons National Surgical Quality Improvement Program targeted lower extremity revascularization database from 2012 to 2015 to identify patients with CLTI and isolated infrageniculate arterial disease who underwent primary infrageniculate bypass or endovascular intervention. We excluded patients with a history of ipsilateral revascularization and proximal interventions. The end points were major adverse limb event (MALE), major adverse cardiovascular event (MACE), amputation at 30 days, reintervention, patency, and mortality. Multivariable logistic regression was used to determine the association of a bypass-first or an endovascular-first intervention with outcomes.

Results

There were 1355 CLTI patients undergoing first-time revascularization to the infrageniculate arteries (821 endovascular-first revascularizations and 534 bypass-first revascularizations) identified. There was no significant difference in adjusted rate of 30-day MALE in the bypass-first vs endovascular-first revascularization cohort (9% vs 11.2%; odds ratio [OR], 0.73; 95% confidence interval [CI], 0.50-1.08). However, the incidence of transtibial or proximal amputation was lower in the bypass-first cohort (4.3% vs 7.4%; OR, 0.60; CI, 0.36-0.98). Patients with bypass-first revascularization had higher wound complication rates (9.7% vs 3.7%; OR, 2.75; CI, 1.71-4.42) compared with patients in the endovascular-first cohort. Compared with the endovascular-first cohort, the incidence of 30-day MACE was significantly higher in bypass-first patients (6.9% vs 2.6%; adjusted OR, 3.88; CI, 2.18-6.88), and 30-day mortality rates were 3.23% vs 1.8% (adjusted OR, 2.77; CI, 1.26-6.11). There was no difference in 30-day untreated loss of patency, reintervention of treated arterial segment, readmissions, and reoperations between the two cohorts. In subgroup analysis after exclusion of dialysis patients, there was also no significant difference in MALE or amputation between the bypass-first and endovascular-first cohorts.

Conclusions

CLTI patients with isolated infrageniculate arterial disease treated by a bypass-first approach have a significantly lower 30-day amputation. However, this benefit was not observed when dialysis patients were excluded. The bypass-first cohort had a higher incidence of MACE compared with an endovascular-first strategy. These results reaffirm the need for randomized controlled trials, such as the Bypass versus Angioplasty in Severe Ischaemia of the Leg (BASIL-2) trial and Best Endovascular vs Best Surgical Therapy in Patients with Critical Limb Ischemia (BEST-CLI), to provide level 1 evidence for the role of endovascular-first vs bypass-first revascularization strategies in the treatment of this population of challenging patients.  相似文献   
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We report the case of a littoral‐cell angioma of the spleen, a recently described benign vascular tumour, whose imaging and pathological characteristics have been discussed only by a few authors. The diagnosis was made after elective splenectomy. The CT images, scintigraphy and histological specimens are presented, and differential diagnoses discussed.  相似文献   
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OBJECTIVE: To determine if there is a diurnal pattern in the clinical symptoms of HELLP (Hemolysis, Elevated Liver enzymes, Low Platelets) syndrome. STUDY DESIGN: A retrospective study was performed in 134 pregnancies complicated by HELLP syndrome. The medical records were reviewed to describe each HELLP episode. Time of day was divided into three periods, day, evening, and night. The following parameters were categorized according to the time of day: onset of symptoms, consultation by the doctor, initial blood sampling, diagnosis and decrease of symptoms. Biochemical parameters at clinical presentation and consecutive changes within 24 h were recorded. RESULTS: In 65 pregnancies 77 HELLP episodes were well documented. Times of onset of symptoms and consultation by the doctor were significantly higher during the evening and night (p < 0.001), whereas times of diagnosis and decrease of symptoms occurred significantly more during the day (p < 0.001). In only 49.3% of the cases were diagnostic laboratory criteria met at clinical presentation. This was mainly due to platelet values in excess of 100 x 10(9)/l. Several hours later (median 8 h, range 2-23) the decrease in platelets occurred. CONCLUSIONS: A diurnal pattern exists in the clinical symptoms of HELLP syndrome that is characterized by an exacerbation during the night and recovery during the day. There is a considerable delay between the onset of symptoms and the fulfillment of diagnostic laboratory criteria.  相似文献   
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Liver disease alters the pharmacokinetic and pharmacodynamic properties of hepatically eliminated drugs. The main factors influenced are plasma albumin levels, enzyme balance (induction & inhibition) and drug binding to tissue proteins. The influence of lidocaine on serum, heart and liver propranolol levels in Wistar rats after liver injury induced by carbon tetrachloride CCl4 0.4 ml/kg x 2/wkl, was investigated. 40 male Wistar rats were divided into four groups (I, II, III, IV; n=10), Group I animals received only propranolol (labelled + cold substance) 40 mg/kg/12 h p.o., group II propranolol plus lidocaine in a single dose of 4mg/kg s.c., group III was treated with CCl4 for 6 weeks and received propranolol x2 at the same dosage as group I, while group VI was treated with CCl4 and the same drug dosage as group II. The simultaneous administration of H3-propranolol and lidocaine increased propranolol levels in the serum and tissues. The liver in damaged animals showed an increase of propranolol level under lidocaine co-administration, probably due to CCl4 induced liver enzyme activity, resulting in a rapid propranolol metabolism or to competition between both drug protein binding sites. The increased propranolol levels in the heart after lidocaine administration were probably due to attributed to its high affinity for heart tissue. Consequently, as regards the therapeutic approach for patients with liver disease receiving propranolol their propranolol dosage should be reduced when lidocaine is co-administered.  相似文献   
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Chronic exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) has been shown to lead to the development of hepatotoxicity and carcinogenicity in the liver of female rats. In this study, we investigated hepatic gene downregulation in response to acute and subchronic TCDD exposure. We identified 61 probes which exhibited a downregulation of twofold or greater following subchronic (13 weeks) exposure to TCDD. Comparative analysis of the hepatic expression of these 61 probes was conducted with rats subchronically exposed to PeCDF, PCB126, PCB153, and a mixture of PCB126 and PCB153. PCB153 produced little or no alteration in these probes, while the binary mixture mimicked most closely the downregulation observed with TCDD. To discern if the repression of genes within this probe set occur as a primary response to TCDD exposure, we analyzed the early responsiveness of 11 genes at 6, 24, and 72 h following a single exposure to TCDD. We observed early repression of the 11 genes within this early time course, indicating that the repression of this subset of genes occurs as a primary response to TCDD exposure and not as a secondary response to 13 weeks of subchronic treatment. In addition, the gender, species, and AhR dependence of these responses were also investigated. Gender- and species-dependent repression was observed within this subset of genes. Furthermore, utilizing AhR knockout mice, we were able to determine the AhR-dependent downregulation of seven of 11 genes. Together these results assist efforts to understand the multitude of effects imposed by TCDD and AhR ligands on gene expression.  相似文献   
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