Adverse cardiac events after vascular surgery are prevalent despite negative results of preoperative stress testing.

OBJECTIVE: Cardiac risk assessment is a critical component of vascular disease management before surgical intervention. The predictive risk reduction of a negative cardiac stress test result remains poorly defined. The objective of this study was to compare the incidence of postoperative cardiac events among patients with negative stress test results vs those who did not undergo testing. METHODS: We reviewed all patients who underwent elective open abdominal aortic aneurysm repair, suprainguinal bypass, endovascular aneurysm repair (EVAR), carotid endarterectomy (CEA), and infrainguinal bypass within the Vascular Study Group of New England from 2003 to 2017. We excluded patients with positive stress test results (n = 3312) and studied two mutually exclusive groups: elective surgery patients with a negative stress test result and elective surgery patients with no stress test (total n = 26,910). The primary outcome was a composite of in-hospital postoperative cardiac events (dysrhythmia, heart attack, heart failure) or death. RESULTS: A preoperative stress test was obtained in 66.3% of open repairs, 42.8% of suprainguinal bypasses, 37.1% of EVARs, 36.0% of CEAs, and 31.2% of infrainguinal bypasses. The proportion of patients receiving a preoperative stress test varied widely across centers, from 37.1% to 80.0%. The crude odds ratio of in-hospital postoperative cardiac event or death was 1.37 (95% confidence interval [CI], 1.07-1.76) for open repair and 1.52 (CI, 1.13-2.03) for suprainguinal bypass, indicating that patients with negative stress test results before these procedures were 37% and 52% more likely to suffer a postoperative event or die compared with patients selected to proceed directly to surgery without testing. Conversely, the crude odds ratio was 0.92 (CI, 0.66-1.29) for EVAR, 0.92 (CI, 0.70-1.21) for CEA, and 1.13 (CI, 0.90-1.40) for infrainguinal bypass, indicating that patients undergoing these procedures had a similar likelihood of sustaining an event whether they had a negative stress test result or proceeded directly to surgery without a stress test. CONCLUSIONS: The use of cardiac stress testing before vascular surgery varies widely throughout New England. Whereas patients are often appropriately selected to proceed directly to surgery, a negative preoperative stress test result should not assuage the concern for an adverse outcome as these patients retain a substantial likelihood of cardiac events, especially after large-magnitude procedures.

Hyperbaric oxygen for patients with above-knee amputations, persistent ischemia, and nonreconstructable vascular disease.

We describe four patients with above-knee amputations whose stump wounds failed to heal. After numerous revascularization attempts, these patients were diagnosed with nonreconstructable pelvic and groin vascular disease and were facing hip disarticulation. With the addition of hyperbaric oxygen treatment to vigilant wound care and negative pressure therapy, these patients healed their amputation stumps and were fit with prostheses. At their most recent follow-up, all patients were ambulating and using their prostheses.

Lesion complexity drives the cost of superficial femoral artery endovascular interventions.

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.

Results of transcaval embolization for sac expansion from type II endoleaks after endovascular aneurysm repair.

OBJECTIVE: Management of type II endoleaks after endovascular aneurysm repair can be problematic. This study reports our experience with a relatively novel strategy to treat this complication, transcaval coil embolization (TCCE) of the aneurysm sac. METHODS: We reviewed 29 consecutive patients undergoing TCCE from 2010 to 2013. Demographics, operative details, and outcomes were assessed. RESULTS: Since 2006, 29 TCCEs have been performed at our institution in 26 patients for sac expansion from type II endoleaks. Patients were male (83%) and former or current smokers (88%), with an average age of 78 ± 7.1 years. TCCE was performed a mean of 4.2 ± 4 years after initial endovascular aneurysm repair. Endoleaks resulted in a mean sac growth of 1.2 ± 1 cm in diameter and 37% ± 32% by volume. Forty-six percent had prior procedures (5 translumbar, 3 transarterial, 3 transcaval, 1 aortic cuff, and 1 iliac limb extension). Two patients had no flow identified in the aneurysm sac after puncture was successful, and one was found to have a hygroma rather than arterial flow. An additional two patients had ultimate embolization from sac access between the endograft iliac limb and arterial wall after transcaval puncture failed, for a 90% procedural success (83% for transcaval technical success). Mean fluoroscopy time was 27 ± 13 minutes with 29 ± 21 mL of contrast material used and a median of 10 coils per case. Additional adjuncts included thrombin injection (17%), intravascular ultrasound (14%), sac pressure measurements (28%), and on-table integrated computed tomography (17%). Median length of stay was 1 day (range, 0-5 days). There were no procedural adverse events. Reintervention was required in five cases (three repeated TCCEs, two graft relinings). One-year freedom from reintervention was 95%. At a mean 16.5 months of follow-up, 70% experienced no further endoleak and had stable or decreasing sac diameters. There have been no ruptures during follow-up. CONCLUSIONS: In this series, TCCE for treatment of aneurysm enlargement due to type II endoleaks was safe and relatively effective despite prior failed interventions in nearly half of the cases. TCCE is a useful alternative in cases in which the anatomy makes other approaches difficult or impossible.

Endovascular aneurysm repair delivery redesign leads to quality improvement and cost reduction.

OBJECTIVE: Endovascular aneurysm repair (EVAR) is now a mainstay of therapy for abdominal aortic aneurysm, although it remains associated with significant expense. We performed a comprehensive analysis of EVAR delivery at an academic medical center to identify targets for quality improvement and cost reduction in light of impending health care reform. METHODS: All infrarenal EVARs performed from April 2011 to March 2012 were identified (N = 127). Procedures were included if they met standard commercial instructions for use guidelines, used a single manufacturer, and were billed to Medicare diagnosis-related group 238 (n = 49). By use of DMAIC (define, measure, analyze, improve, and control) quality improvement methodology (define, measure, analyze, improve, control), targets for EVAR quality improvement were identified and high-yield changes were implemented. Procedure technical costs were calculated before and after process redesign. RESULTS: Perioperative services and clinic visits were identified as targets for quality improvement efforts and cost reduction. Mean technical costs before the intervention were $31,672, with endograft implants accounting for 52%. Pricing redesign in collaboration with hospital purchasing reduced mean EVAR technical costs to $28,607, a 10% reduction in overall cost, with endograft implants now accounting for 46%. Perioperative implementation of instrument tray redesign reduced instrument use by 32% (184 vs 132 instruments), saving $50,000 annually. Unnecessary clinic visits were reduced by 39% (1.6 vs 1.1 clinic visits per patient) through implementation of a preclinic imaging protocol. There was no difference in mean length of stay after the intervention. CONCLUSIONS: Comprehensive EVAR delivery redesign leads to cost reduction and waste elimination while preserving quality. Future efforts to achieve more competitive and transparent device pricing will make EVAR more cost neutral and enhance its financial sustainability for health care systems.

Inferior vena cava filter retrieval provides no advantage in the average patient.

BACKGROUND: Inferior vena cava (IVC) filter placement is performed to mitigate the risk of pulmonary embolism (PE) when anticoagulation is contraindicated or ineffective. Technical advances now allow catheter-based filter retrieval. Many believe the benefits of retrieval are self-evident, yet retrieval carries an inherent complication risk and cost. The purpose of this study was to quantitatively weigh the risks and benefits of IVC filter retrieval using formal decision analysis. METHODS: A Markov state-transition model was used to simulate two clinical scenarios: to leave a previously placed IVC filter or to retrieve it. Analysis was performed during the lifetime of the individual, and outcomes were expressed in quality-adjusted life-years (QALYs). The base case is a 60-year-old man with a filter placed within 3 months who no longer requires mechanical thromboprophylaxis. Potential events included PE, filter complications, and death from all other causes during each cycle. Tolls were used to incorporate the disutility of short-term treatment for PE and filter complications. For the base case and sensitivity analyses, we used utilities and probabilities derived from the literature. RESULTS: In the base case scenario, leaving the filter in place was preferred to filter retrieval, yielding 22.3 vs 21.9 QALYs. One-way sensitivity analysis demonstrated that filter retrieval may be preferable if the utility of living with a filter is <0.98. For all probabilities of retrieval and PE mortality, leaving the filter in place is preferred. CONCLUSIONS: Leaving a previously placed IVC filter provides a 0.4 QALY benefit over retrieving the filter for the average patient. This decision is sensitive to the utility of living with the IVC filter.

Bone marrow aspirate injection for treatment of critical limb ischemia with comparison to patients undergoing high-risk bypass grafts.

OBJECTIVE: Bone marrow cell therapy (BMCT) for patients with critical limb ischemia (CLI) is a potential treatment in candidates with poor options for standard revascularization procedures. Whereas clinical trials are ongoing, there are few comparative data to assess its efficacy compared with bypass. METHODS: Patients with poor revascularization options underwent BMCT between 2011 and 2013. Outcomes were compared with those of a cohort of CLI patients undergoing infrainguinal bypass thought to be at high risk for graft failure (tissue loss, a tibial target, and a previous endovascular treatment or bypass). BMCT patients underwent harvest of bone marrow that was then concentrated and injected intramuscularly into the ischemic limb. RESULTS: There were 20 BMCT patients and 35 high-risk bypass patients. All BMCT patients had either rest pain (80%) or tissue loss (80%). The majority (65%) had a prior intervention (bypass, 30%; endovascular, 58%) compared with high-risk bypass patients, all of whom had previous revascularization attempts (bypass, 43% [P = .35]; endovascular, 77% [P = .14]). Mean follow-up was 773 days after BMCT and 972 days after high-risk bypass. All patients tolerated BMCT without issues or complications. A second BMCT treatment was performed in 21% because of clinical deterioration. Wound healing occurred in 75% at 1.5 years, including patients receiving second injections, all of which resolved. Rest pain improved in 87.5% of patients. Pain completely resolved in 58% at 1.5 years. Ankle-brachial index improvement was 0.23 (±0.25). Three BMCT patients went on to amputation. One-year freedom from major amputation or death was 78% for BMCT vs 69% for high-risk bypass (P = .60). CONCLUSIONS: BMCT is a potential option in CLI patients who are not candidates for bypass or endovascular intervention. Limb salvage is unexpectedly high in this population with few other options.

Retrospective review of superficial femoral artery stenting in diabetic patients: thiazolidinedione use may decrease reinterventions.

BACKGROUND: Diabetics are known to have inferior outcomes following peripheral vascular interventions. Thiazolidinediones are oral diabetic agents which improve outcomes following coronary bare metal stenting. No studies have been performed evaluating thiazolidinedione use and outcomes following lower extremity endovascular interventions. We hypothesize that diabetic patients taking thiazolidinediones at the time of primary superficial femoral artery (SFA) stenting have fewer reinterventions. METHODS: A retrospective review was performed to identify diabetic patients undergoing primary SFA stenting. The unit of analysis was the extremity. The primary outcome was freedom from target lesion revascularization stratified by thiazolidinedione use, evaluated by Kaplan Meier curves and a log rank test. A Cox proportional hazards model was constructed to determine variables associated with freedom from target lesion revascularization. RESULTS: SFA stents were placed in 138 extremities in 128 diabetic patients between August 1, 2001 and July 15, 2012. Twenty-four patients were taking thiazolidinediones at the time of SFA stenting. All patients taking thiazolidinediones had TASC A or B lesions. Twenty-seven extremities in the non-thiazolidinedione group had TASC C or D lesions and were excluded to control for disease severity. Freedom from target lesion revascularization was significantly higher in diabetics taking thiazolidinediones at 2 years, 88.5% vs. 59.4%, P = 0.02, SE < 10%. Cox modeling identified a protective trend for thiazolidinedione use (thiazolidinedione use HR 0.33, 95% CI 0.09-1.13), whereas critical limb ischemia and insulin use were associated with trends for worse freedom from target lesion revascularization. CONCLUSIONS: This pilot, translation study demonstrates that diabetic patients taking thiazolidinediones at the time of primary SFA stenting have decreased reintervention rates at 2 years. These results may be explained by higher adiponectin levels or other anti-inflammatory effects in patients taking thiazolidinedione. National and regional quality improvement registries should consider collecting information regarding specific diabetic regimens and use of PPAR agonists such as cilostazol and fibrates.

Cilostazol is associated with improved outcomes after peripheral endovascular interventions.

OBJECTIVE: Although cilostazol is commonly used as an adjunct after peripheral vascular interventions, its efficacy remains uncertain. We assessed the effect of cilostazol on outcomes after peripheral vascular interventions using meta-analytic techniques. METHODS: We searched MEDLINE (1946-2012), Cochrane CENTRAL (1996-2012), and trial registries for studies comparing cilostazol in combination with antiplatelet therapy to antiplatelet therapy alone after peripheral vascular interventions. Treatment effects were reported as pooled risk/hazard ratio (HR) with random-effects models. RESULTS: Two randomized trials and four retrospective cohorts involving 1522 patients met inclusion criteria. Across studies, mean age ranged from 65 to 76 years, and the majority of patients were male (64%-83%); mean follow-up ranged from 18 to 37 months. Most interventions were in the femoropopliteal segment, and overall, 68% of patients had stents placed. Pooled estimates demonstrated that the addition of cilostazol was associated with decreased restenosis (relative risk [RR], 0.71; 95% confidence interval [CI], 0.60-0.84; P < .001), improved amputation-free survival (HR, 0.63; 95% CI, 0.47-0.85; P = .002), improved limb salvage (HR, 0.42; 95% CI, 0.27-0.66; P < .001), and improved freedom from target lesion revascularization (RR, 1.36; 95% CI, 1.14-1.61; P < .001). There was no significant reduction in mortality among those receiving cilostazol (RR, 0.73; 95% CI, 0.45-1.19; P = .21). CONCLUSIONS: The addition of cilostazol to antiplatelet therapy after peripheral vascular interventions is associated with a reduced risk of restenosis, amputation, and target lesion revascularization in our meta-analysis of six studies. Consideration of cilostazol as a medical adjunct after peripheral vascular interventions is warranted, presuming these findings are broadly generalizable.

The financial implications of endovascular aneurysm repair in the cost containment era.

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.

Lean principles optimize on-time vascular surgery operating room starts and decrease resident work hours.

OBJECTIVE: Lean process improvement techniques are used in industry to improve efficiency and quality while controlling costs. These techniques are less commonly applied in health care. This study assessed the effectiveness of Lean principles on first case on-time operating room starts and quantified effects on resident work hours. METHODS: Standard process improvement techniques (DMAIC methodology: define, measure, analyze, improve, control) were used to identify causes of delayed vascular surgery first case starts. Value stream maps and process flow diagrams were created. Process data were analyzed with Pareto and control charts. High-yield changes were identified and simulated in computer and live settings prior to implementation. The primary outcome measure was the proportion of on-time first case starts; secondary outcomes included hospital costs, resident rounding time, and work hours. Data were compared with existing benchmarks. RESULTS: Prior to implementation, 39% of first cases started on time. Process mapping identified late resident arrival in preoperative holding as a cause of delayed first case starts. Resident rounding process inefficiencies were identified and changed through the use of checklists, standardization, and elimination of nonvalue-added activity. Following implementation of process improvements, first case on-time starts improved to 71% at 6 weeks (P = .002). Improvement was sustained with an 86% on-time rate at 1 year (P < .001). Resident rounding time was reduced by 33% (from 70 to 47 minutes). At 9 weeks following implementation, these changes generated an opportunity cost potential of $12,582. CONCLUSIONS: Use of Lean principles allowed rapid identification and implementation of perioperative process changes that improved efficiency and resulted in significant cost savings. This improvement was sustained at 1 year. Downstream effects included improved resident efficiency with decreased work hours.

Functional outcomes following catheter-based iliac vein stent placement.

OBJECTIVES: Although previous reports have demonstrated the efficacy of catheter-directed thrombolytic therapy and iliac vein stent placement for the management of iliofemoral deep vein thrombosis (DVT), functional outcomes remain undefined. The purpose of this study was to determine midterm outcomes and functional quality of life among patients treated with iliac vein stenting. METHODS: Records of all the patients treated with iliac vein stent placement between March 2004 and March 2011 were examined for primary patency, assisted primary patency, and secondary patency. Midterm functional outcomes were measured quantitatively, including ongoing symptoms and return to work status. RESULTS: Over the study interval, 32 patients (33 limbs) underwent iliac vein stent placement. In all, 72% (n = 23) of these patients were female, with an average age of 43 years. In all, 78% (n = 25) of the patients were diagnosed with acute DVT, 89% of which occurred in the left leg. Catheter-directed thrombolysis was utilized in 92% (23 of 25) of the patients with acute DVT. All patients treated with thrombolysis and stent placement presented with pain and edema in the affected limb. One-year primary, assisted primary, and secondary patencies were 75%, 96%, and 96%, respectively. Freedom from reintervention at 1 year was 83%. Treatment was associated with a sustained significant reduction in pain (91% vs 6%, P < .001) and edema (97% vs 12%, P < .001) at a mean follow-up of 29 months (range 5-83 months), at which time 89% of the patients reported to be at their pre-DVT functional status. CONCLUSIONS: Aggressive therapy of symptomatic iliac vein stenosis or occlusion with venography, catheter-directed thrombolysis, and iliac vein stent placement provides durable patency and freedom from reintervention. Most patients can anticipate good functional recovery with decreased pain, decreased edema, and high likelihood of returning to work.

Clinical effectiveness of secondary interventions for restenosis after renal artery stenting.

OBJECTIVE: Secondary interventions for renal artery restenosis (RAS) after renal artery stenting are common, despite limited data about their effectiveness. This study was designed to evaluate the outcomes of endovascular treatment of recurrent RAS. METHODS: We conducted a retrospective review of patients who underwent renal artery stenting between 2001 and 2011 at Dartmouth-Hitchcock Medical Center. Patients who required secondary interventions were compared with control patients who underwent only primary interventions for RAS. Multivariate regression models were used to identify factors associated with successful outcomes, as measured by changes in blood pressure, estimated glomerular filtration rate, and number of antihypertensive medications required. RESULTS: Sixty-five secondary (57 patients) renal interventions were undertaken for recurrent RAS associated with progressive hypertension or renal dysfunction and compared with outcomes after 216 primary (180 patients) renal artery stenting procedures. Patients undergoing primary vs secondary interventions did not differ significantly in the number of preoperative antihypertensive medications used, comorbid conditions, or blood pressure. All primary and secondary interventions were performed with stents and showed no difference in procedural complications. At a mean follow-up of 23 months (range, 1-128 months), similar improvements in renal function and blood pressure were found between patients undergoing primary and secondary interventions, and there was no difference in rates of restenosis or survival between cohorts. Regression models showed that the use of embolic protection devices was associated with improved renal function after primary (odds ratio [OR], 2.0; 95% confidence interval [CI], 1.1-3.8; P < .05) and secondary (OR, 4.7; 95% CI, 1.7-12.5; P < .05) interventions, whereas statin therapy was associated with improved renal (OR, 2.0; 95% CI, 1.3-3.2; P < .05) and blood pressure response (OR, 4.1; 95% CI, 1.1-14.9; P < .05) after secondary interventions. CONCLUSIONS: Patients undergoing secondary interventions for recurrent RAS have outcomes that are comparable with those for primary interventions. These data suggest that repeated endovascular procedures for RAS can be undertaken with similar expectations for clinical improvement and may be further improved by routine use of embolic protection devices and statin therapy.

Severity of chronic obstructive pulmonary disease is associated with adverse outcomes in patients undergoing elective abdominal aortic aneurysm repair.

INTRODUCTION: Although chronic obstructive pulmonary disease (COPD) has been implicated as a risk factor for abdominal aortic aneurysm (AAA) rupture, its effect on surgical repair is less defined. Consequently, variation in practice persists regarding patient selection and surgical management. The purpose of this study was to analyze the effect of COPD on patients undergoing AAA repair. METHODS: We reviewed a prospective regional registry of 3455 patients undergoing elective open AAA repair (OAR) and endovascular AAA repair (EVAR) from 23 centers in the Vascular Study Group of New England from 2003 to 2011. COPD was categorized as none, medical (medically treated but not oxygen [O2]-dependent), and O2-dependent. End points included in-hospital death, pulmonary complications, major postoperative adverse events (MAEs), extubation in the operating room, and 5-year survival. Survival was determined using life-table analysis based on the Social Security Death Index. Predictors of in-hospital and long-term mortality were determined by multivariate logistic regression and Cox proportional hazards analysis. RESULTS: During the study interval, 2043 patients underwent EVAR and 1412 patients underwent OAR with a nearly equal prevalence of COPD (35% EVAR vs 36% OAR). O2-dependent COPD (4%) was associated with significantly increased in-hospital mortality, pulmonary complications, and MAE and was also associated with significantly decreased extubation in the operating room among patients undergoing both EVAR and OAR. Five-year survival was significantly diminished among all patients undergoing AAA repair with COPD (none, 78%; medical, 72%; O2-dependent, 42%; P < .001). By multivariate analysis, O2-dependent COPD was independently associated with in-hospital mortality (odds ratio 2.02, 95% confidence interval, 1.0-4.0; P = .04) and diminished 5-year survival (hazard ratio, 3.02; 95% confidence interval, 2.2-4.1; P < .001). CONCLUSIONS: Patients with O2-dependent COPD undergoing AAA repair suffer increased pulmonary complications, overall MAE, and diminished long-term survival. This must be carefully factored into the risk-benefit analysis before recommending elective AAA repair in these patients.

Carotid endarterectomy in asymptomatic patients with limited life expectancy.

BACKGROUND AND PURPOSE: Data from randomized trials assert that asymptomatic patients undergoing carotid endarterectomy (CEA) must live 3 to 5 years to realize the benefit of surgery. We examined how commonly CEA is performed among asymptomatic patients with limited life expectancy. METHODS: Within the American College of Surgeons National Quality Improvement Project we identified 8 conditions associated with limited life expectancy based on survival estimates using external sources. We then compared rates of 30-day stroke, death, and myocardial infarction after CEA between asymptomatic patients with and without life-limiting conditions. RESULTS: Of 12,631 CEAs performed in asymptomatic patients, 2525 (20.0%) were in patients with life-limiting conditions or diagnoses. The most common conditions were severe chronic obstructive pulmonary disease and American Society of Anesthesiologists Class IV designation. Patients with life-limiting conditions had significantly higher rates of perioperative complications, including stroke (1.8% versus 0.9%, P<0.001), death (1.4% versus 0.3%, P<0.001), and stroke/death (2.9% versus 1.1%, P<0.001). Even after adjustment for other comorbidities, patients with life-limiting conditions were nearly 3 times more likely to experience perioperative stroke or death than those without these conditions (OR, 2.8; 95% CI, 2.1-3.8; P<0.001). CONCLUSION: CEA is performed commonly in asymptomatic patients with life-limiting conditions. Given the high rates of postoperative stroke/death in these patients as well as their limited life expectancy, the net benefit of CEA in this population remains uncertain. Health policy research examining the role of CEA in asymptomatic patients with life-limiting conditions is necessary and may serve as a potential source for significant healthcare savings in the future.

Variation in thromboembolic complications among patients undergoing commonly performed cancer operations.

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.

The impact of adjunctive iliac stenting on femoral-femoral bypass in contemporary practice.

OBJECTIVES: Most reports of femoral-femoral bypass (FFB) were published before the era of endovascular intervention. This study examines the utilization and impact of adjunctive endovascular intervention on FFB in contemporary practice. METHODS: We reviewed 253 FFB performed in 247 patients between 1984 and 2010. Primary endpoints, including graft patency, primary-assisted patency, limb salvage, and survival, were assessed using Kaplan-Meier life-table analysis. Univariate and multivariate analyses were performed to determine predictors of primary endpoints. RESULTS: The indication for FFB included claudication (27%; n = 69) and critical limb ischemia (72%; n = 184). Forty-eight patients (19%) were treated urgently for acute ischemia. Mean follow-up was 5.6 ± 5.5 years. Over the study interval, adjunctive iliac percutaneous transluminal angioplasty (PTA)/stent placement increased significantly from 0% to 54% (P trend < .001), while the rate of axillofemoral bypass or no inflow procedure decreased from 100% to 46% (P trend < .001). Despite increased utilization, iliac PTA/stenting was associated with decreased 5-year primary graft patency of 44% compared with 74% for axillofemoral bypass patients and 71% in patients with no adjunctive inflow procedure (P = .004). Patients with inflow iliac PTA/stents also had diminished 5-year assisted primary patency of 61% compared with 85% for axillofemoral bypass patients and 87% in patients without inflow revascularization (P = .002). Adjunctive iliac PTA/stenting did not impact limb salvage or overall survival. Five-year primary patency among claudicants and critical leg ischemia patients was 65% and 68%, respectively. CONCLUSIONS: The incidence of iliac PTA/stent placement in conjunction with FFB has increased significantly over time in contemporary practice. Reliance on iliac stent placement for FFB inflow is paradoxically associated with both diminished primary and assisted primary graft patency when compared with historical controls. These findings highlight the importance of patient selection and inflow consideration when performing FFB.

A meta-analysis of anticoagulation for calf deep venous thrombosis.

OBJECTIVE: This meta-analysis was initiated to assess the efficacy and safety of anticoagulation therapy for adult patients with isolated calf vein deep venous thrombosis (DVT). METHODS: We searched MEDLINE (1950-October 2010), the Cochrane Library (1993-October 2010), trial registries, meeting abstracts, and selected references, using no limits. Included studies compared the results of anticoagulation (vitamin K antagonist or therapeutic heparin) for a minimum of 30 days vs the results of no anticoagulation in adults with calf vein DVT proved by ultrasound imaging or venograph who were monitored for at least 30 days. Two independent reviewers extracted data using a piloted standardized form. Methodologic quality was assessed using the Cochrane Risk of Bias tool for randomized controlled trials (RCTs) and the Newcastle-Ottawa Quality Assessment Scale for cohort and case-control studies. Discrepancies were resolved by consensus or by a third reviewer. Authors were contacted for additional information if necessary. Outcomes were pooled using Peto fixed-effects models. RESULTS: Of 2328 studies identified, two RCTs and six cohorts (126 patients treated with anticoagulation and 328 controls) met selection criteria. The methodologic quality of most studies was poor. Pulmonary embolism (PE; odds ratio, 0.12; 95% confidence interval, 0.02-0.77; P = .03) and thrombus propagation (odds ratio, 0.29; 95% confidence interval, 0.14-0.62; P = .04) were significantly less frequent in those who received anticoagulation. Significant heterogeneity existed in studies reporting mortality rates, but these demonstrated a trend toward fewer deaths with anticoagulation. When limited to randomized trials, the protective effect of anticoagulation for PE was no longer statistically significant, but the benefit for preventing thrombus progression persisted. Adverse events such as bleeding were sparsely reported but favored controls (P = .65). CONCLUSIONS: Our review suggests that anticoagulation therapy for calf vein DVT may decrease the incidence of PE and thrombus propagation. However, due to poor methodologic quality and few events among included studies for PE, this finding is not robust. Thrombus propagation appears reduced with anticoagulation treatment. A rigorous RCT will assist in treatment decisions for calf vein DVT.

Completion duplex ultrasound predicts early graft thrombosis after crural bypass in patients with critical limb ischemia.

OBJECTIVE: To determine if intraoperative distal graft end-diastolic velocity (EDV) using completion duplex ultrasound (CDU) predicts patency of crural bypass in patients with critical limb ischemia (CLI). METHODS: Records of 116 non-consecutive patients who underwent crural revascularization with vein conduit and CDU between 1998 and 2008 were reviewed. Bypass grafts were performed for rest pain (34%) or tissue loss (66%), while 56% of the reported cases were categorized as "disadvantaged" because of compromised vein quality or diseased arterial outflow. A 10-MHz low-profile transducer was used to image the entire bypass at case completion. Technical adequacy of the grafts was verified by absence of retained valves, arteriovenous fistulas, or localized velocity increases and presence of bypass-dependent distal pulses. Modified Rutherford scores were calculated as surrogate markers of runoff resistance and compared to distal graft EDV. The primary study end point was graft patency during a 1-year posttreatment period. Patency rates were determined using Kaplan-Meier life table methodology and compared using the log-rank test. Predictors of graft patency were determined by Cox proportional hazards. RESULTS: Primary, primary-assisted, and secondary patency for all crural bypasses were 62%, 66%, and 70% at 1 year, respectively. When stratified by tertiles of distal graft EDV (0 - <5 cm/s, 5-15 cm/s, >15 cm/s), 1-year primary patency rates were 32%, 64%, and 84% (P = .001). Low (0 - < 5 cm/s) distal graft EDV (hazard ratio [HR], 3.3 confidence interval [CI], 1.74-6.41; P < .001), poor-quality conduit (HR, 2.5; CI, 1.19-5.21; P = .016), age <70 (HR, 2.08; CI, 1.06-4.00; P = .031), and lack of statin use (HR, 2.04; CI, 1.04-4.00; P = .038) were independent predictors of graft failure. While the modified Rutherford score correlated with distal graft EDV (P = .05), it was not an independent predictor of patency (P = .58). Predictors of low EDV (<5 cm/s) included single-vessel runoff (odds ratio [OR], 3.33; CI, 1.14-9.71; P = .027), poor conduit (OR, 2.94; CI, 1.16-7.41; P = 0.024), and diabetes (OR, 2.86; CI, 1.14-7.21; P = .025). CONCLUSIONS: Distal graft EDV predicts crural vein graft patency in patients with CLI. Grafts with EDV <5 cm/s remain at high risk for early failure. The impacts on patency of statins, age, and poor-quality conduit are, again, confirmed. These results highlight the value of EDV using intraoperative CDU for anticipating and, possibly, improving results of open crural revascularization.

Long-term results of open and endovascular revascularization of superficial femoral artery occlusive disease.

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.