Randall R. De Martino

Prior failed ipsilateral percutaneous endovascular intervention in patients with critical limb ischemia predicts poor outcome after lower extremity bypass

BACKGROUND Although open surgical bypass remains the standard revascularization strategy for patients with critical limb ischemia (CLI), many centers now perform peripheral endovascular intervention (PVI) as the first-line treatment for these patients. We sought to determine the effect of a prior ipsilateral PVI (iPVI) on the outcome of subsequent lower extremity bypass (LEB) in patients with CLI. METHODS A retrospective cohort analysis of all patients undergoing infrainguinal LEB between 2003 and 2009 within hospitals comprising the Vascular Study Group of New England (VSGNE) was performed. Primary study endpoints were major amputation and graft occlusion at 1 year postoperatively. Secondary outcomes included in-hospital major adverse events (MAE), 1-year mortality, and composite 1-year major adverse limb events (MALE). Event rates were determined using life table analyses and comparisons were performed using the log-rank test. Multivariate predictors were determined using a Cox proportional hazards model with multilevel hierarchical adjustment. RESULTS Of 1880 LEBs performed, 32% (n = 603) had a prior infrainguinal revascularization procedure (iPVI, 7%; ipsilateral bypass, 15%; contralateral PVI, 3%; contralateral bypass, 17%). Patients with prior iPVI, compared with those without a prior iPVI, were more likely to be women (32 vs 41%; P = .04), less likely to have tissue loss (52% vs 63%; P = .02), more likely to require arm vein conduit (16% vs 5%; P = .001), and more likely to be on statin (71% vs 54%; P = .01) and beta blocker therapy (92% vs 81%; P = .01) at the time of their bypass procedure. Other demographic factors were similar between these groups. Prior PVI or bypass did not alter 30-day MAE and 1-year mortality after the index bypass. In contrast, 1-year major amputation and 1-year graft occlusion rates were significantly higher in patients who had prior iPVI than those without (31% vs 20%; P = .046 and 28% vs 18%; P = .009), similar to patients who had a prior ipsilateral bypass (1 year major amputation, 29% vs 20%; P = .022; 1 year graft occlusion, 33% vs 18%; P = .001). Independent multivariate predictors of higher 1-year amputation and graft occlusion rates were prior iPVI, prior ipsilateral bypass, dialysis dependence, prosthetic conduit and distal (tibial and pedal) bypass target. CONCLUSIONS Prior iPVI is highly predictive for poor outcome in patients undergoing LEB for CLI with higher 1-year amputation and graft occlusion rates than those without prior revascularization, similar to prior ipsilateral bypass These findings provide information, which may help with the complex decisions surrounding revascularization options in patients with CLI.

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.

Venous thromboembolism after surgery for inflammatory bowel disease: are there modifiable risk factors? Data from ACS NSQIP.

BACKGROUND: Although it is commonly reported that IBD patients are at increased risk for venous thromboembolic events, little real-world data exist regarding their postoperative incidence and related outcomes in everyday practice. OBJECTIVE: We aimed to identify the rate of venous thromboembolism and modifiable risk factors within a large cohort of surgical IBD patients. DESIGN: We performed a retrospective review of IBD patients who underwent colorectal procedures. PATIENTS: Patient data were obtained from the American College of Surgeons National Surgical Quality Improvement Program 2004 to 2010 Participant Use Data Files. MAIN OUTCOME MEASURES: The primary outcomes measured were short-term (30-day) postoperative venous thromboembolism (deep vein thrombosis and pulmonary embolism). Clinical variables were analyzed by univariate and multivariate analyses to identify modifiable risk factors for these events. RESULTS: A total of 10,431 operations were for Crohn’s disease (52.1%) or ulcerative colitis (47.9%), and 242 (2.3%) venous thromboembolic events occurred (178deep vein thromboses, 46 pulmonary embolisms, 18 both) for a combined rate of 1.4% in Crohn’s disease and 3.3% in ulcerative colitis. Deep vein thrombosis and pulmonary embolism each occurred at a mean of 10.8 days postoperatively (range for each, 0–30 days). A multivariate model found that bleeding disorder, steroid use, anesthesia time, emergency surgery, hematocrit <37%,malnutrition, and functional status were potentially modifiable risk factors that remained associated (p < 0.05) with venous thromboembolism on regression analysis. Patients with thromboembolism had longer length of stay (18.8 vs 8.9 days), more complications (41% vs 18%), and a higher risk of death (4% vs 0.9%). LIMITATIONS: This study was limited by its retrospective design and its limited generalizability to nonparticipating hospitals. CONCLUSIONS: Inflammatory bowel disease patients are at increased risk for postoperative venous thromboembolism. Reducing preoperative anemia, steroid use, malnutrition, and anesthesia time may also reduce venous thromboembolism in this at-risk population. Risk-reducing, preventative strategies are needed in this at-risk population.

Optimal selection of asymptomatic patients for carotid endarterectomy based on predicted 5-year survival.

OBJECTIVE Although carotid endarterectomy (CEA) is performed to prevent stroke, long-term survival is essential to ensure benefit, especially in asymptomatic patients. We examined factors associated with 5-year survival following CEA in patients with asymptomatic internal carotid artery (ICA) stenosis. METHODS Prospectively collected data from 4114 isolated CEAs performed for asymptomatic stenosis across 24 centers in the Vascular Study Group of New England between 2003 and 2011 were used for this analysis. Late survival was determined with the Social Security Death Index. Cox proportional hazard models were used to identify risk factors for mortality within the first 5 years after CEA and to calculate a risk score for predicting 5-year survival. RESULTS Overall 3- and 5-year survival after CEA in asymptomatic patients were 90% (95% CI 89%-91%) and 82% (95% CI 81%-84%), respectively. By multivariate analysis, increasing age, diabetes, smoking history, congestive heart failure, chronic obstructive pulmonary disease, poor renal function (estimated glomerular filtration rate <60 or dialysis dependence), absence of statin use, and worse contralateral ICA stenosis were all associated with worse survival. Patients classified as low (27%), medium (68%), and high risk (5%) based on number of risk factors had 5-year survival rates of 96%, 80%, and 51%, respectively (P < .001). CONCLUSIONS More than four out of five asymptomatic patients selected for CEA in the Vascular Study Group of New England achieved 5-year survival, demonstrating that, overall, surgeons in our region selected appropriate patients for carotid revascularization. However, there were patients selected for surgery with high risk profiles, and our models suggest that the highest risk patients (such as those with multiple major risk factors including age ≥ 80, insulin-dependent diabetes, dialysis dependence, and severe contralateral ICA stenosis) are unlikely to survive long enough to realize a benefit of prophylactic CEA for asymptomatic stenosis. Predicting survival is important for decision making in these patients.

Developing Strategies for Predicting and Preventing Readmissions in Vascular Surgery

The escalating cost burden of hospital readmission has prompted recent nationwide efforts aimed at reducing the incidence of this important quality measure. Because patients undergoing vascular surgery account for a significant proportion of readmissions, vascular surgeons may face reduced reimbursements in the near future if these trends continue. However, risk factors associated with readmission remain poorly defined, and further research is needed to identify interventions that will prevent readmission following vascular procedures. Accordingly, this manuscript will (1) propose a conceptual model to explain the driving forces behind readmissions in vascular surgery, (2) review current evidence directed at identifying risk factors and evaluating interventions to reduce readmissions across different medical and surgical specialties, and (3) identify key areas in patient care where targeted research or interventions may be implemented in vascular surgery.

Perioperative management with antiplatelet and statin medication is associated with reduced mortality following vascular surgery

OBJECTIVE Many patients undergoing vascular surgical procedures are not on appropriate medical therapy. This study sought to examine the variation and impact of antiplatelet (AP) and statin therapy on early and late mortality in patients undergoing vascular surgery in our region. METHODS We studied all patients (n = 14,489) undergoing elective carotid endarterectomy (n = 6978), carotid stenting (n = 524), and suprainguinal (n = 763) and infrainguinal bypass (n = 3053), as well as patients with known coronary risk factors undergoing open (n = 1044) and endovascular (n = 2127) abdominal aortic aneurysm repair from 2005 to 2012 in the Vascular Study Group of New England. Optimal medical management was defined as treatment with both AP and statin agents, preoperatively and at discharge. We analyzed temporal, procedural, and center variation of medication use. Multivariable analyses were used to determine the adjusted impact of AP and statin therapy on 30-day mortality and 5-year survival. RESULTS Optimal medical management improved over the study interval (55% in 2005 to 68% in 2012; P trend < .01) with carotid interventions having the highest rates of optimal medications use (carotid artery stenting, 78%; carotid endarterectomy, 74%) and abdominal aortic aneurysm repair in patients with known cardiac risk factors having the lowest (open, 57%; endovascular aneurysm repair, 56%). Optimal medication use varied by center as well (range, 40%-86%). Preoperative AP and statin use was associated with reduced 30-day mortality (odds ratio, 0.76; 95% confidence interval [CI], 0.5-1.05; P = .09). AP and statin prescription at discharge was additive in survival benefit with improved 5-year survival (hazard ratio, 0.5; 95% CI, 0.4-0.7; P < .01) that was consistent across procedure types. Patients prescribed AP and statin at discharge had 5-year survival of 79% (95% CI, 77%-81%) compared with only 61% (95% CI, 52%-68%; P < .001) for patients on neither medication. CONCLUSIONS AP and statin therapy preoperatively and at discharge was associated with reduced 30-day mortality and an absolute 18% improved 5-year survival after vascular surgery. However, one-third of patients are suboptimally managed in real world practice. This demonstrates an opportunity for quality improvement that can substantially improve survival after vascular surgery.

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.

Comparison of carotid endarterectomy and stenting in real world practice using a regional quality improvement registry

OBJECTIVE Carotid artery stenting (CAS) vs endarterectomy (CEA) remains controversial and has been the topic of recent randomized controlled trials. The purpose of this study was to compare the practice and outcomes of CAS and CEA in a real world setting. METHODS This is a retrospective analysis of 7649 CEA and 430 CAS performed at 17 centers from 2003 to 2010 within the Vascular Study Group of New England (VSGNE). The primary outcome measures were (1) any in-hospital stroke or death and (2) any stroke, death, or myocardial infarction (MI). Patients undergoing CEA in conjunction with cardiac surgery were excluded. Multivariate logistic regression was performed to identify predictors of stroke or death in patients undergoing CAS. RESULTS CEA was performed in 17 centers by 111 surgeons, while CAS was performed in 6 centers by 30 surgeons and 8 interventionalists. Patient characteristics varied by procedure. Patients undergoing CAS had a higher prevalence of coronary artery disease, congestive heart failure, diabetes, and prior ipsilateral CEA. Embolic protection was used in 97% of CAS. Shunts were used in 48% and patches in 86% of CEA. The overall in-hospital stroke or death rate was higher among patients undergoing CAS (2.3% vs 1.1%; P = .03). Overall stroke, death, or MI (2.8% CAS vs 2.1% CEA; P = .32) were not different. Asymptomatic patients had similar rates of stroke or death (CAS 0.73% vs CEA 0.89%; P = .78) and stroke, death, or MI (CAS 1.1% vs CEA 1.8%; P = .40). Symptomatic patients undergoing CAS had higher rates of stroke or death (5.1% vs 1.6%; P = .001), and stroke, death, or MI (5.8% vs 2.7%; P = .02). By multivariate analysis, major stroke (odds ratio, 4.5; 95% confidence interval [CI], 1.9-10.8), minor stroke (2.7; CI, 1.5-4.8), prior ipsilateral CEA (3.2, CI, 1.7-6.1), age >80 (2.1; CI, 1.3-3.4), hypertension (2.6; CI, 1.0-6.3), and a history of chronic obstructive pulmonary disease (1.6; CI, 1.0-2.4) were predictors of stroke or death in patients undergoing carotid revascularization. CONCLUSIONS In our regional vascular surgical practices, the overall outcomes of CAS and CEA are similar for asymptomatic patients. However, symptomatic patients treated with CAS are at a higher risk for stroke or death.

Participation in the Vascular Quality Initiative is associated with improved perioperative medication use, which is associated with longer patient survival

OBJECTIVE Medical management (MM) with antiplatelet (AP) and statin therapy is recommended for most patients undergoing vascular surgery and has been advocated by the Vascular Quality Initiative (VQI). We analyzed the effect of VQI participation on perioperative (preoperative and postoperative) MM use over time and the effect of discharge MM on patient survival. METHODS We studied VQI patients treated with MM preoperatively and at discharge from 2005 to 2014, including all elective carotid endarterectomy/carotid stenting (n = 28,092), suprainguinal/infrainguinal bypass (n = 11,362), peripheral vascular interventions (n = 24,476), open/endovascular abdominal aortic aneurysm repair (n = 13,503), and thoracic endovascular aneurysm repair (n = 702). We examined trends of MM use over time, as well as the effect of duration of VQI participation on MM use. Multivariable logistic regression analysis was performed to identify factors associated with MM use. In addition, the Cox proportional hazards model was used to identify factors associated with 5-year survival. RESULTS MM with AP and statin preoperatively and postoperatively across VQI centers improved from 55% in 2005 to 68% in 2009, with a subsequent overall decline to 62% by 2014, coincident with many new centers with lower MM rates joining VQI in 2010. Longer center participation in VQI was associated with improved perioperative MM overall. This was also noted across all procedure types, with MM increasing from 47% to 82% for aneurysm repairs and 69% to 83% for carotid procedures from 1 to 12 years of participation in VQI. After multivariable adjustment, centers in VQI ≥3 years were 30% more likely to have patients on MM (odds ratio, 1.3, 95% confidence interval [CI], 1.3-1.4). Importantly, discharge on AP and statin therapy was associated with improved 5-year survival, compared with discharge on neither medication (82% [95% CI, 81%-83%] vs 67% [95% CI, 62%-72%]), and an adjusted hazard ratio for death of 0.6 (95% CI, 0.5-0.7; P < .001). Discharge on a single medication was associated with intermediate survival at 5 years (AP only: 77% [95% CI, 75%-79%]; statin only: 73% [95% CI, 68%-77%]). CONCLUSIONS These data demonstrate that MM is associated with improved survival after a number of vascular procedures. Importantly, VQI participation improves the use of MM, demonstrating that involvement in an organized quality effort can affect patient outcomes.

Optimal selection of patients for elective abdominal aortic aneurysm repair based on life expectancy

OBJECTIVE Elective abdominal aortic aneurysm (AAA) repair is beneficial when rupture is likely during a patients expected lifetime. The purpose of this study was to identify predictors of long-term mortality after elective AAA repair for moderately sized AAAs (<6.5-cm diameter) to identify patients unlikely to benefit from surgery. METHODS We analyzed 2367 elective infrarenal AAA (<6.5 cm) repairs across 21 centers in New England from 2003 to 2011. Our main outcome measure was 5-year life-table survival. Cox proportional hazards analysis was used to describe associations between patient characteristics and 5-year survival. RESULTS During the study period, 1653 endovascular AAA repairs and 714 open AAA repairs were performed. Overall, 5-year survival rates were similar by procedure type (75% endovascular repair, 80% open repair; P = .14). Advanced age ≥75 years (hazard ratio [HR], 2.0; P < .01) and age >80 years (HR, 2.6; P < .01), coronary artery disease (HR, 1.4; P < .04), unstable angina or recent myocardial infarction (HR, 4.6; P < .01), oxygen-dependent chronic obstructive pulmonary disease (HR, 2.7; P < .01), and estimated glomerular filtration rate <30 mL/min/1.73 m(2) (HR, 2.8; P < .01) were associated with poor survival. Aspirin (HR, 0.8; P < .03) and statin (HR, 0.7; P < .01) use were associated with improved survival. We used these risk factors to develop risk strata for low-risk, medium-risk, and high-risk groups with survival, respectively, of 85%, 69%, and 43% at 5 years (P < .001). CONCLUSIONS More than 75% of patients with moderately sized AAAs who underwent elective repair in our region survived 5 years, but 4% were at high risk for 5-year mortality. Patients with multiple risk factors, especially age >80 years, unstable angina, oxygen-dependent chronic obstructive pulmonary disease, and estimated glomerular filtration rate <30 mL/min/1.73 m(2), are unlikely to achieve sufficient long-term survival to benefit from surgery, unless their AAA rupture risk is very high.