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101.
102.

Objective

The purpose of this study was to investigate the roles of the kallikrein-kinin system and matrix metalloproteinases (MMPs) in the development of arterial restenosis attributable to intimal hyperplasia in the femoropopliteal arteries.

Methods

This report describes a single-center prospective study of 27 patients with peripheral artery disease who required percutaneous transluminal angioplasty and stenting of the femoropopliteal segment using covered stent grafts. The blood concentrations of total and kininogen fractions were evaluated using immunoenzymatic methods. Plasma kallikrein was evaluated by the colorimetric method. Tissue kallikrein was evaluated by the spectrophotometric method. The activity of kininase II was measured by fluorometric analysis. Quantification of MMPs was performed by zymography, and tissue inhibitors of metalloproteinases were measured by enzyme-linked immunosorbent assay.

Results

Four (15%) of the treated patients developed restenosis at the 6-month follow-up evaluation. These patients had significantly lower levels of high-molecular-weight kininogens (24 hours; P < .05) and low-molecular-weight kininogens (before, P < .05; 24 hours, P < .01; 6 months, P < .05) and lower levels of tissue inhibitor of metalloproteinases-2 (6 months; P < .05) than the patients without restenosis. The activity levels of plasma and tissue kallikrein, kininase II, and MMPs did not differ significantly between the patients with and without restenosis.

Conclusions

This study demonstrates an involvement of the kallikrein-kinin system in in-stent restenosis, although we could not confirm the participation of metalloproteinases in the restenosis process.  相似文献   
103.

Objective

Isolated visceral artery dissections are rare entities with no current consensus guidelines for treatment and follow-up. This study aims to evaluate the presentation, management, outcomes, and follow-up practices for patients with isolated visceral artery dissections and to compare those with and without symptoms.

Methods

In this retrospective analysis, we identified all patients with isolated celiac artery and/or isolated superior mesenteric artery dissections at a single institution between September 2006 and December 2014. Patients with concomitant aortic dissections were excluded. Cases were stratified by symptom status. Presentation, anatomic findings, treatment, outcomes, and follow-up imaging were then compared between symptomatic and asymptomatic patients.

Results

We identified 25 patients including 15 with symptoms and 10 without. There were no differences in patient comorbidities; however, symptomatic patients more frequently presented with thrombus (n = 10; 67% vs n = 1; 10%; P = .01) and inflammation (n = 8; 53% vs n = 1; 10%; P = .04), and trended toward increased stenosis (n = 12; 80% vs n = 4; 40%; P = .09) compared with asymptomatic patients. All asymptomatic patients were treated with observation alone with vessel diameter enlargement noted in 33% (n = 2) of patients on follow-up imaging. Among symptomatic patients, standard treatment included a short course of anticoagulation (mean, 4.5 months) with lifelong antiplatelet therapy. Three patients underwent operative intervention for persistent or worsening symptoms, two during the index admission and one 10 months after presentation for chronic abdominal pain. Approximately 70% (n = 17) of patients in each group had follow-up imaging (computed tomography angiography: n = 14; 56%; magnetic resonance angiography: n = 4; 16%; ultrasound: n = 13; 52%). Among patients treated nonoperatively, no patients complained of symptoms at follow-up, and 50% of those with inflammation on initial imaging had resolution. Twenty-five percent (n = 4) of patients had an increase in vessel size; however, all vessels remained less than 2 cm in maximal diameter. There were no ruptures or related deaths in either group.

Conclusions

Among patients with visceral artery dissection, no ruptures occurred but diameter enlargement was documented. This disease progression suggests that routine surveillance may be appropriate; however, transitioning early to ultrasound imaging should be considered to decrease radiation, contrast, and associated costs.  相似文献   
104.

Objective

The targeted vascular module in the American College of Surgeons National Surgical Quality Improvement Program (NSQIP) consists of self-selected hospitals that choose to collect extra clinical details for better risk adjustment and improved procedure-specific outcomes. The purpose of this study was to compare patient selection and outcomes between targeted and nontargeted hospitals in the NSQIP regarding the operative management of abdominal aortic aneurysm (AAA).

Methods

We identified all patients who underwent endovascular aneurysm repair (EVAR) or open AAA repair from 2011 to 2013 and compared cases by whether the operation took place in a targeted or nontargeted hospital. EVAR and open repair as well as intact and ruptured aneurysms were evaluated separately. Only variables contained in both modules were used to evaluate rupture status and operation type. All thoracoabdominal aneurysms were excluded. Univariate analysis was performed for intact and ruptured EVAR and open repair grouped by complexity, defined as visceral involvement in open repair and a compilation of concomitant procedures for EVAR. Multivariable models were developed to identify effect of hospital type on mortality.

Results

There were 17,651 AAA repairs identified. After exclusion of aneurysms involving the thoracic aorta (n = 352), there were 1600 open AAA repairs at targeted hospitals (21% ruptured) and 2725 at nontargeted hospitals (19% ruptured) and 4986 EVARs performed at targeted hospitals (6.7% ruptured) and 7988 at nontargeted hospitals (5.2% ruptured). There was no significant difference in 30-day mortality rates between targeted and nontargeted hospitals for intact aneurysms (EVAR noncomplex, 1.8% vs 1.4% [P = .07]; open repair noncomplex, 4.2% vs 4.5% [P = .7]; EVAR complex, 5.0% vs 3.2% [P = .3]; open repair complex, 8.0% vs 6.0% [P = .2]). For ruptured aneurysms, again there was no difference in mortality between the targeted and nontargeted hospitals (EVAR noncomplex, 23% vs 25% [P = .4]; open repair noncomplex, 38% vs 34% [P = .2]; EVAR complex, 29% vs 33% [P = 1.0]; open repair complex, 27% vs 41% [P = .09]). Multivariable analysis further demonstrated that having an operation at a targeted vs nontargeted hospital had no impact on mortality for both intact and ruptured aneurysms (odds ratio, 1.1 [0.9-1.4] and 1.0 [0.8-1.3], respectively).

Conclusions

This analysis highlights the similarities between targeted and nontargeted hospitals within the NSQIP for AAA operative management and suggests that data from the targeted NSQIP, in terms of AAA management, are generalizable to all NSQIP hospitals.  相似文献   
105.

Objective

The neutrophil-to-lymphocyte ratio (NLR) has been used as a surrogate marker of systemic inflammation. We sought to investigate the association between NLR and wound healing in diabetic wounds.

Methods

The outcomes of 120 diabetic foot ulcers in 101 patients referred from August 2011 to December 2014 were examined retrospectively. Demographic, patient-specific, and wound-specific variables as well as NLR at baseline visit were assessed. Outcomes were classified as ulcer healing, minor amputation, major amputation, and chronic ulcer.

Results

The subjects' mean age was 59.4 ± 13.0 years, and 67 (66%) were male. Final outcome was complete healing in 24 ulcers (20%), minor amputation in 58 (48%) and major amputation in 16 (13%), and 22 chronic ulcers (18%) at the last follow-up (median follow-up time, 6.8 months). In multivariate analysis, higher NLR (odds ratio, 13.61; P = .01) was associated with higher odds of nonhealing.

Conclusions

NLR can predict odds of complete healing in diabetic foot ulcers independent of wound infection and other factors.  相似文献   
106.

Introduction

When a patient with ruptured abdominal aortic aneurysm (rAAA) presents at a facility ill-equipped to provide care, transfer may provide the best chance for survival. Large distances and long travel times provide challenging barriers to prompt and appropriate care in the western United States.

Methods

The Western Vascular Society (WVS) adopted a set of guidelines in considering transfer of a patient with an rAAA using published literature, membership survey and input, and existing recommendations. This article reports the guidelines and describes the process and rationale behind their development.

Results

Fifteen guidelines for transfer and care of rAAAs were endorsed by the WVS.

Conclusions

When local care cannot be provided, transfer guidelines may standardize care for rAAAs and may be applicable across may practice settings.  相似文献   
107.

Objective

The effect of gender on outcomes after lower extremity revascularization is controversial. The aim of our systemic review and meta-analysis was to evaluate the gender-related outcomes after peripheral vascular interventions.

Methods

We systematically searched MEDLINE, Embase, Cochrane Database, and Scopus to identify studies comparing outcomes after revascularization according to gender. A random-effects model was used to pool outcomes. Time-to-event data were reported using hazard ratios (HRs) and dichotomous data were presented using odds ratios (ORs).

Results

Included were 40 studies. Pooling of short-term outcomes after intervention showed that women had significantly increased risks of 30-day mortality (OR, 1.31; 95% confidence interval [CI], 1.11-1.55; P = .001), amputation (OR, 1.07; 95% CI, 1.02-1.12; P = .002), early graft thrombosis (OR, 1.56; 95% CI, 1.28-1.90; P < .0001), embolization (OR, 1.64; 95% CI, 1.24-2.17; P = .0005), incisional site complication (OR, 1.56; 95% CI, 1.34-1.80; P < .0001), cardiac events (OR, 1.21; 95% CI, 1.16-1.26; P < .0001), stroke (OR, 1.35; 95% CI, 1.19-1.53; P < .0001), and pulmonary complication (OR, 1.07; 95% CI, 1.03-1.12; P = .0006). No significant differences were found between women and men for short-term reinterventions (OR, 1.06; 95% CI, 0.73-1.54; P = .74) and renal complications (OR, 1.03; 95% CI, 0.76-1.39; P = .86). No significant differences in long-term outcomes between women and men were found, with similar rates of cumulative survival (HR, 1.10; 95% CI, 0.97-1.24; P = .12), primary patency (HR, 1.14; 95% CI, 1.00-1.30; P = .06), secondary patency (HR, 1.07; 95% CI, 0.86-1.34; P = .54), and limb salvage (HR, 0.93; 95% CI, 0.70-1.24; P = .63). However, in the open surgery subgroup, women had significantly reduced survival compared with men (HR, 1.21; 95% CI, 1.01-1.44; P = .04).

Conclusions

Women have inferior short-term outcomes but similar long-term outcomes compared with men after lower limb revascularization. A higher treatment threshold may be warranted when considering intervening on women with symptomatic peripheral arterial disease owing to the increased risks of postprocedural mortality and complications.  相似文献   
108.

Objective

Medicare studies have shown increased perioperative mortality in women compared with men following endovascular and open abdominal aortic aneurysm (AAA) repair. However, a recent regional study of high-volume centers, adjusting for anatomy but limited in sample size, did not show sex to be predictive of worse outcomes. This study aimed to evaluate sex differences after intact AAA repair in a national clinical registry.

Methods

The targeted vascular module of the National Surgical Quality Improvement Program was queried to identify patients undergoing endovascular aneurysm repair (EVAR) or open repair for intact, infrarenal AAA from 2011 to 2014. Univariate analysis was performed using the Fisher exact test and Mann-Whitney test. Multivariable logistic regression was used to account for differences in comorbidities, aneurysm details, and operative characteristics.

Results

We identified 6661 patients (19% women) who underwent intact AAA repair (87% EVAR; 83% women vs 88% men; P < .001). Women were older (median age, 76 vs 73 years; P < .001), had smaller aneurysms (median, 5.4 vs 5.5 cm; P < .001), and had more chronic obstructive pulmonary disease (22% vs 17%; P < .001). Among patients undergoing EVAR, women had longer operative times (median, 138 [interquartile range, 103-170] vs 131 [106-181] minutes; P < .01) and more often underwent renal (6.3% vs 4.1%; P < .01) and lower extremity (6.6% vs 3.8%; P < .01) revascularization. After open repair, women had shorter operative time (215 [177-304] vs 226 [165-264] minutes; P = .02), but women less frequently underwent lower extremity revascularization (3.1% vs 8.2%; P = .03). Thirty-day mortality was higher in women after EVAR (3.2% vs 1.2%; P < .001) and open repair (8.0% vs 4.0%; P = .04). After adjusting for repair type, age, aneurysm diameter, and comorbidities, female sex was independently associated with mortality (odds ratio [OR], 1.7; 95% confidence interval [CI], 1.1-2.6; P = .02) and major complications (OR, 1.4; CI, 1.1-1.7; P < .01) after intact AAA repair. However, after adjusting for aortic size index rather than for aortic diameter, the association between female sex and mortality (OR, 1.5; CI, 0.98-2.4; P = .06) and major complications (OR, 1.1; CI, 0.9-1.4; P = .24) was reduced.

Conclusions

Women were at higher risk for 30-day death and major complications after intact AAA repair. Some of this disparity may be explained by differences in aortic size index, which should be further evaluated to determine the ideal threshold for repair.  相似文献   
109.

Objective

During endovascular aneurysm repair (EVAR), severely tortuous aortoiliac anatomy can alter the deployment and conformability of the endograft. The accuracy of treatment length measurements is commonly recognized to be affected by severe tortuosity. However, the exact mechanism of the postintervention length discrepancy is poorly understood. The objective of this study was to determine the mechanism of how severe aortoiliac tortuosity influences the endograft and native aorta during EVAR and its impact on the distal sealing zone.

Methods

A prospectively collected vascular surgery database was retrospectively reviewed at a university-affiliated medical center to identify the study patients. Patients who underwent EVAR with the main body device deployed on the side of the severely tortuous iliac artery were selected. Severe aortoiliac tortuosity was defined as having either aortoiliac or common iliac angulation <90 degrees.

Results

A total of 469 patients between 2008 and 2014 underwent EVAR using the Endurant endograft (Medtronic Cardiovascular, Santa Rosa, Calif). Severe aortoiliac tortuosity was observed in 36% of patients; 17 patients were found to have the main body placed on the side of severe tortuosity without an extension limb. There was a significant shortening of the main body endograft length from 169 mm before EVAR to 147 mm after EVAR (P < .001). The treatment length of the main body, measured from the lowest renal artery to hypogastric artery, also significantly shortened from 179 mm to 170 mm (P < .001). There was a decrease in tortuosity at the most angulated portion of the aneurysm after EVAR, in which angulation changed from 86 degrees to 114 degrees (P < .001). There was no significant change in treatment length (P = .859) and angulation (P = .195) on the nontortuous side of the aneurysm.

Conclusions

The study observed significant shortening of endografts and native aorta and iliac arteries in patients with severe aortoiliac tortuosity during EVAR. This shortening effect can have a negative impact on the distal sealing zone during EVAR. A longer main body or an extension limb should be considered when one is faced with severely tortuous aneurysms.  相似文献   
110.

Objective

Patients with end-stage renal disease have multiple comorbidities and are at increased risk for postoperative complications and resource utilization. Our goal was to determine the rate and causes of 30-day and 90-day hospital readmissions after the creation of outpatient hemodialysis access.

Methods

We retrospectively reviewed all outpatient upper extremity hemodialysis access creations performed at our medical center from 2008 to 2015. Readmission was defined as any inpatient status admission ≤30 and 90 days. Reasons for such admissions were analyzed, and multivariate analyses assessed risk factors.

Results

We identified 537 patients (60% male). Average age was 59 years. Access type included radiocephalic (4.5%), brachiocephalic (50.7%), brachiobasilic (22.5%), and prosthetic (20%) arteriovenous fistulas. The 90-day mortality rate was 0.7%. Postoperative hospital readmission rates were 25.5% at 30 days and 47.7% at 90 days. Reasons for admission were access related in 10.9% and dialysis catheter related in 6.9%. Other reasons for admission included shortness of breath/volume overload (15.8%), gastrointestinal (11.9%), cardiac/chest pain (10.9%), unrelated infectious causes (11.9%), failure to thrive (5%), altered mental status (4%), electrolyte abnormalities (3%), and musculoskeletal (2.5%). Preoperative predictors of all cause 30-day readmission included dementia (odds ratio [OR], 5.76; 95% confidence interval [CI], 1.34-24.8; P = .018), hypertension (OR, 3.92; 95% CI, 1.07-14.4; P = .039), chronic obstructive pulmonary disease (OR, 2.19; 95% CI, 1.01-4.76; P = .046), and current smoking (OR, 2.14; 95% CI, 1.32-3.47; P = .002). Predictors of all cause 90-day readmission were hepatic insufficiency (OR, 6.08; 95% CI, 1.2-30.8; P = .029), hypertension (OR, 3.43; 95% CI, 1.36-8.65; P = .009), black race (OR, 2.47; 95% CI, 1.48-4.14; P = .001), Hispanic ethnicity (OR, 2.04; 95% CI, 1.01-4.11; P = .046), and obesity (OR, 1.5; 95% CI, 1.02-2.19; P = .039). Predictors of 90-day access-related readmission included chronic obstructive pulmonary disease (OR, 5.27; 95% CI, 1.38-20.0; P = .015), previous stroke (OR, 3.76; 95% CI, 1.5-9.4; P = .005), being on dialysis at time of the operation (OR, 2.8; 95% CI, 1.17-6.84; P = .022), and prosthetic graft placement (OR, 2.86; 95% CI, 1.07-7.6; P = .036). An additional 9.7% had at least one emergency department presentation ≤90 days but were not admitted.

Conclusions

Patients undergoing placement of hemodialysis access are at high risk for readmission mostly from causes unrelated to their operation. This has an effect for global care for these patients as well as care of these patients in accountable care organizations.  相似文献   
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