Objective There is widespread evidence that cancer confers an increased risk of deep venous thrombosis (DVT). This risk is thought to vary among different cancer types. The purpose of this study is ...to better define the incidence of thrombotic complications among patients undergoing surgical treatment for a spectrum of prevalent cancer diagnoses in contemporary practice. Methods All patients undergoing one of 11 cancer surgical operations (breast resection, hysterectomy, prostatectomy, colectomy, gastrectomy, lung resection, hepatectomy, pancreatectomy, cystectomy, esophagectomy, and nephrectomy) were identified by Current Procedural Terminology and International Classification of Diseases, Ninth Revision codes using the American College of Surgeons National Surgical Quality Improvement Program database (2007-2009). The study endpoints were DVT, pulmonary embolism (PE), and overall postoperative venous thromboembolic events (VTE) within 1 month of the index procedure. Multivariate logistic regression was utilized to calculate adjusted odds ratios for each endpoint. Results Over the study interval, 43,808 of the selected cancer operations were performed. The incidence of DVT, PE, and total VTE within 1 month following surgery varied widely across a spectrum of cancer diagnoses, ranging from 0.19%, 0.12%, and 0.28% for breast resection to 6.1%, 2.4%, and 7.3%, respectively, for esophagectomy. Compared with breast cancer, the incidence of VTE ranged from a 1.31-fold increase in VTE associated with gastrectomy (95% confidence interval, 0.73-2.37; P = .4) to a 2.68-fold increase associated with hysterectomy (95% confidence interval, 1.43-5.01; P = .002). Multivariate logistic regression revealed that inpatient status, steroid use, advanced age (≥60 years), morbid obesity (body mass index ≥35), blood transfusion, reintubation, cardiac arrest, postoperative infectious complications, and prolonged hospitalization were independently associated with increased risk of VTE. Conclusions The incidence of VTE and thromboembolic complications associated with cancer surgery varies substantially. These findings suggest that both tumor type and resection magnitude may impact VTE risk. Accordingly, such data support diagnosis and procedural-specific guidelines for perioperative VTE prophylaxis and can be used to anticipate the risk of potentially preventable morbidity.
Objective Controversy persists regarding the perioperative management of clopidogrel among patients undergoing carotid endarterectomy (CEA). This study examined the effect of preoperative dual ...antiplatelet therapy (aspirin and clopidogrel) on in-hospital CEA outcomes. Methods Patients undergoing CEA in the Vascular Quality Initiative were analyzed (2003-2014). Patients on clopidogrel and aspirin (dual therapy) were compared with patients taking aspirin alone preoperatively. Study outcomes included reoperation for bleeding and thrombotic complications defined as transient ischemic attack (TIA), stroke, or myocardial infarction. Secondary outcomes were in-hospital death and composite stroke/death. Univariate and multivariable analyses assessed differences in demographics and operative factors. Propensity score-matched cohorts were derived to control for subgroup heterogeneity. Results Of 28,683 CEAs, 21,624 patients (75%) were on aspirin and 7059 (25%) were on dual therapy. Patients on dual therapy were more likely to have multiple comorbidities, including coronary artery disease ( P < .001), congestive heart failure ( P < .001), and diabetes ( P < .001). Patients on dual therapy were also more likely to have a drain placed ( P < .001) and receive protamine during CEA ( P < .001). Multivariable analysis showed that dual therapy was independently associated with increased reoperation for bleeding (odds ratio OR, 1.71; 95% confidence interval CI, 1.20-2.42; P = .003) but was protective against TIA or stroke (OR, 0.61; 95% CI, 0.43-0.87; P = .007), stroke (OR, 0.63; 95% CI, 0.41-0.97; P = .03), and stroke/death (OR, 0.66; 95% CI, 0.44-0.98; P = .04). Propensity score matching yielded two groups of 4548 patients and showed that patients on dual therapy were more likely to require reoperation for bleeding (1.3% vs 0.7%; P = .004) but less likely to suffer TIA or stroke (0.9% vs 1.6%; P = .002), stroke (0.6% vs 1.0%; P = .04), or stroke/death (0.7% vs 1.2%; P = .03). Within the propensity score-matched groups, patients on dual therapy had increased rates of reoperation for bleeding regardless of carotid symptom status. However, asymptomatic patients on dual therapy demonstrated reduced rates of TIA or stroke (0.6% vs 1.5%; P < .001), stroke (0.4% vs 0.9%; P = .01), and composite stroke/death (0.5% vs 1.0%; P = .02). Among propensity score-matched patients with symptomatic carotid disease, these differences were not statistically significant. Conclusions Preoperative dual antiplatelet therapy was associated with a 40% risk reduction for neurologic events but also incurred a significant increased risk of reoperation for bleeding after CEA. Given its observed overall neurologic protective effect, continued dual antiplatelet therapy throughout the perioperative period is justified. Initiating dual therapy in all patients undergoing CEA may lead to decreased neurologic complication rates.
Objective Endovascular aneurysm repair (EVAR) is associated with significant direct device costs. Such costs place EVAR at odds with efforts to constrain healthcare expenditures. This study examines ...the procedure-associated costs and operating margins associated with EVAR at a tertiary care academic medical center. Methods All infrarenal EVARs performed from April 2011 to March 2012 were identified (n = 127). Among this cohort, 49 patients met standard commercial instruction for use guidelines, were treated using a single manufacturer device, and billed to Medicare diagnosis-related group (DRG) 238. Of these 49 patients, net technical operating margins (technical revenue minus technical cost) were calculated in conjunction with the hospital finance department. EVAR implant costs were determined for each procedure. DRG 238-associated costs and length of stay were benchmarked against other academic medical centers using University Health System Consortium 2012 data. Results Among the studied EVAR cohort (age 75, 82% male, mean length of stay, 1.7 days), mean technical costs totaled $31,672. Graft implants accounted for 52% of the allocated technical costs. Institutional overhead was 17% ($5495) of total technical costs. Net mean total technical EVAR-associated operating margins were −$4015 per procedure. Our institutional costs and length of stay, when benchmarked against comparable centers, remained in the lowest quartile nationally using University Health System Consortium costs for DRG 238. Stent graft price did not correlate with total EVAR market share. Conclusions EVAR is currently associated with significant negative operating margins among Medicare beneficiaries. Currently, device costs account for over 50% of EVAR-associated technical costs and did not impact EVAR market share, reflecting an unawareness of cost differential among surgeons. These data indicate that EVAR must undergo dramatic care delivery redesign for this practice to remain sustainable.
Background Common femoral artery (CFA) endarterectomy with iliac stenting or stent grafting can be an alternative to traditional open surgery in patients with aortoiliac occlusive disease. We report ...the long-term outcomes of this approach. Methods Patients undergoing CFA endarterectomy with simultaneous iliac stenting/stent grafting between 1997 and 2006 were retrospectively reviewed. Technical success, clinical and hemodynamic outcomes, and 5-year patency using life-table methodology were determined. Factors associated with reintervention and mortality were determined by logistic regression analysis. Results A total of 171 patients (mean age, 67 ± 10 years; 38% female; 35% diabetic) underwent 193 CFA endarterectomies and iliac stent/stent grafting. Indications were rest pain (32%), tissue loss (22%), and claudication (46%). External iliac artery (EIA) lesions were present in 39%, and combined common iliac artery (CIA) and EIA lesions were seen in 61% of patients. Complete CIA/EIA occlusions were present in 41% of patients. Stent grafts were used in 41% of patients. Technical success occurred in 98% of patients. Clinical improvement was seen in 92% of patients. Mean ankle-brachial index increased from 0.38 ± 0.32 to 0.72 ± 0.24. Median length of stay was 2 days (range, 1-51 days). Thirty-day mortality was 2.3% and 5-year survival was 60%. Five-year primary, primary-assisted, and secondary patencies were 60%, 97%, and 98% respectively. Endovascular reintervention was required in 14% of patients; inflow surgical procedures were required in 10%. By logistic regression analysis, use of stent grafts compared with bare stents was associated with significantly higher primary patency (87% ± 5% vs 53% ± 7%; P < .01). Conclusion Combined CFA endarterectomy with iliac intervention yield acceptable long-term results. The use of stent grafts compared with bare stents is associated with improved primary patency.
Vascular smooth muscle cell (VSMC) differentiation is an essential component of vascular development. These cells perform biosynthetic, proliferative, and contractile roles in the vessel wall. VSMCs ...are not terminally differentiated and are able to modulate their phenotype in response to changing local environmental cues. There is clear evidence that alterations in the differentiated state of the VSMC play a critical role in the pathogenesis of atherosclerosis and intimal hyperplasia, as well as in a variety of other major human diseases, including hypertension, asthma, and vascular aneurysms. The focus of this review is to provide an overview of the current state of knowledge of molecular mechanisms involved in controlling phenotypic switching of SMCs, with particular focus on examination of signaling pathway that regulate this process.
Acute and chronic radiation injury Brown, Kellie R., MD; Rzucidlo, Eva, MD
Journal of vascular surgery,
2011, 2011-Jan, 2011-01-00, 20110101, Letnik:
53, Številka:
1
Journal Article
Recenzirano
Odprti dostop
Introduction Although all areas of the body are susceptible to radiation injury, different tissues have varying tolerances for radiation exposure. The goal of this summary is to introduce basic ...concepts of radiation biology and discuss the effects of radiation on various tissues. Methods Reference texts and literature were reviewed to summarize key points in radiation biology and the direct and indirect cell damage caused by radiation. Results The most prevalent factor for injury is long exposure time, which can be an issue in lengthy peripheral vascular or aortic interventions. Several key maneuvers can help decrease exposure for both the patient and the physician. Conclusion Radiation induces tissue injury at the cellular level. The use of good fluoroscopic technique is imperative for physician and patient protection.
Objective Optimal diagnosis and management of median arcuate ligament (MAL) syndrome (MALS) remains unclear in contemporary practice. The advent and evolution of laparoscopic and endovascular ...techniques has redirected management toward a less invasive therapeutic algorithm. This study examined our contemporary outcomes of patients treated for MALS. Methods All patients treated for MALS at Dartmouth-Hitchcock Medical Center from 2000 to 2013 were retrospectively reviewed. Demographics and comorbidities were recorded. Freedom from symptoms and freedom from reintervention were the primary end points. Return to work or school was assessed. Follow-up by clinic visits and telephone allowed quantitative comparisons among the patients. Results During the study interval, 21 patients (24% male), with a median age of 42 years, were treated for MALS. All patients complained of abdominal pain in the presence of a celiac stenosis, 16 (76%) also reported weight loss at the time of presentation, and 57% had a concomitant psychiatric history. Diagnostic imaging most commonly used included duplex ultrasound (81%), computed tomography angiography (66%), angiography (57%), and magnetic resonance angiography (5%). Fourteen patients (67%) underwent multiple diagnostic studies. All patients underwent initial laparoscopic MAL release. Seven patients (33%) underwent subsequent celiac stent placement in the setting of recurrent or unresolved symptoms with persistent celiac stenosis at a mean interval of 49 days. Two patients required surgical bypass after an endovascular intervention failed. The 6-month freedom from symptoms was 75% and freedom from reintervention was 64%. Eighteen patients (81%) reported early symptom improvement and weight gain, and 66% were able to return to work. Conclusions A multidisciplinary treatment approach using initial laparoscopic release and subsequent stent placement and bypass surgery provides symptom improvement in most patients treated for MALS. The potential placebo effect, however, remains uncertain. A significant minority of patients will require reintervention, justifying longitudinal surveillance and prudent patient selection. Patients can anticipate functional recovery, weight gain, and return to work with treatment.
Background First-line treatment for patients with superficial femoral arterial (SFA) occlusive disease has yet to be determined. This study compared long-term outcomes between primary SFA stent ...placement and primary femoral-popliteal bypass. Periprocedural patient factors were examined to determine their effect on these results. Methods All femoral-popliteal bypasses and SFA interventions performed in consecutive patients with symptoms Rutherford 3 to 6 between 2001 and 2008 were reviewed. Time-dependent outcomes were analyzed using the Kaplan-Meier method and log-rank test. Cox proportional hazards were performed to determine predictors of graft patency. Multivariate analysis was completed to identify patient covariates most often associated with the primary therapy. Results A total of 152 limbs in 141 patients (66% male; mean age, 66 ± 22 years) underwent femoral-popliteal bypass, and 233 limbs in 204 patients (49% male; mean age, 70 ± 11 years) underwent SFA interventions. Four-year primary, primary-assisted, and secondary patency rates were 69%, 78%, and 83%, respectively, for bypass patients and 66%, 91%, and 95%, respectively, for SFA interventions. Six-year limb salvage was 80% for bypass vs 92% for stenting ( P = .04). Critical limb ischemia (CLI) and renal insufficiency were predictors of bypass failure. Claudication was a predictor of success for SFA stenting. Three-year limb salvage rates for CLI patients undergoing surgery and SFA stenting were 83%. Amputation-free survival at 3 years for CLI patients was 55% for bypass and 59% for SFA interventions. Multivariate predictors (odds ratios and 95% confidence intervals) of covariates most frequently associated with first-line SFA stenting were TransAtlantic Inter-Society Consensus II A and B lesions (5.9 3.4-9.1, P < .001), age >70 years (2.1 1.4-3.1, P < .001), and claudication (1.7 1.1-2.7, P = .01). Regarding bypass as first-line therapy, claudicant patients were more likely to have nondiabetic status (5.6 3.3-9.4, P < .001), creatinine <1.8 mg/dL (4.6 1.5-14.9, P = .01), age <70 years (2.7 CI, 1.6-8.3, P < .001), and presence of an above-knee popliteal artery target vessel (1.9 CI, 1.1-3.4 P = .02). Conclusion Indication, patient-specific covariates, and anatomic lesion classification have significant association when determining surgeon selection of SFA stenting or femoral-popliteal bypass as first-line therapy. Patients with SFA disease can have comparable long-term results when treatment options are well matched to patient-specific and anatomic characteristics.
The phenotypic plasticity of vascular smooth muscle cells (VSMCs) is central to vessel growth and remodeling, but also contributes to cardiovascular pathologies. New technologies including fate ...mapping, single cell transcriptomics, and genetic and pharmacologic inhibitors have provided fundamental new insights into the biology of VSMC. The goal of this review is to summarize the mechanisms underlying VSMC phenotypic modulation and how these might be targeted for therapeutic benefit.
We summarize findings from extensive literature searches to highlight recent discoveries in the mechanisms underlying VSMC phenotypic switching with particular relevance to intimal hyperplasia. PubMed was searched for publications between January 2001 and December 2020. Search terms included VSMCs, restenosis, intimal hyperplasia, phenotypic switching or modulation, and drug-eluting stents. We sought to highlight druggable pathways as well as recent landmark studies in phenotypic modulation.
Lineage tracing methods have determined that a small number of mature VSMCs dedifferentiate to give rise to oligoclonal lesions in intimal hyperplasia and atherosclerosis. In atherosclerosis and aneurysm, single cell transcriptomics reveal a striking diversity of phenotypes that can arise from these VSMCs. Mechanistic studies continue to identify new pathways that influence VSMC phenotypic plasticity. We review the mechanisms by which the current drug-eluting stent agents prevent restenosis and note remaining challenges in peripheral and diabetic revascularization for which new approaches would be beneficial. We summarize findings on new epigenetic (DNA methylation/TET methylcytosine dioxygenase 2, histone deacetylation, bromodomain proteins), transcriptional (Hippo/Yes-associated protein, peroxisome proliferator-activity receptor-gamma, Notch), and β3-integrin-mediated mechanisms that influence VSMC phenotypic modulation. Pharmacologic and genetic targeting of these pathways with agents including ascorbic acid, histone deacetylase or bromodomain inhibitors, thiazolidinediones, and integrin inhibitors suggests potential therapeutic value in the setting of intimal hyperplasia.
Understanding the molecular mechanisms that underlie the remarkable plasticity of VSMCs may lead to novel approaches to treat and prevent cardiovascular disease and restenosis.
Objective Patients who undergo endovascular treatment of superficial femoral artery (SFA) disease vary greatly in lesion complexity and treatment options. This study examined the association of ...lesion severity and cost of SFA stenting and to determine if procedure cost affects primary patency at 1 year. Methods A retrospective record review identified patients undergoing initial SFA stenting between January 1, 2010, and February 1, 2012. Medical records were reviewed to collect data on demographics, comorbidities, indication for the procedure, TransAtlantic Inter-Society Consensus (TASC) II severity, and primary patency. The interventional radiology database and hospital accounting database were queried to determine cost drivers of SFA stenting. Procedure supply cost included any item with a bar code used for the procedure. Associations between cost drivers and lesion characteristics were explored. Primary patency was determined using Kaplan-Meier survival curves and a log-rank test. Results During the study period, 95 patients underwent stenting in 98 extremities; of these, 61% of SFA stents were performed for claudication, with 80% of lesions classified as TASC II A or B. Primary patency at 1 year was 79% for the entire cohort. The mean total cost per case was $10,333. Increased procedure supply cost was associated with adjunct device use, the number of stents, and TASC II severity. Despite higher costs of treating more complex lesions, primary patency at 1 year was similar at 80% for high-cost (supply cost >$4000) vs 78% for low-cost (supply cost <$4000) interventions. Conclusions SFA lesion complexity, as defined by TASC II severity, drives the cost of endovascular interventions but does not appear to disadvantage patency at 1 year. Reimbursement agencies should consider incorporating disease severity into reimbursement algorithms for lower extremity endovascular interventions.