Tumor characteristics associated with engraftment of patient-derived non-small cell lung cancer xenografts in immunocompromised mice.

BACKGROUND: Patient-derived xenograft (PDX) models increasingly are used in translational research. However, the engraftment rates of patient tumor samples in immunodeficient mice to PDX models vary greatly. METHODS: Tumor tissue samples from 308 patients with non-small cell lung cancer were implanted in immunodeficient mice. The patients were followed for 1.5 to approximately 6 years. The authors performed histological analysis of PDXs and some residual tumor tissues in mice with failed PDX growth at 1 year after implantation. Quantitative polymerase chain reaction and enzyme-linked immunoadsorbent assay were performed to measure the levels of Epstein-Barr virus genes and human immunoglobulin G in PDX samples. Patient characteristics were compared for PDX growth and overall survival as outcomes using Cox regression analyses. Disease staging was based on the 7th TNM staging system. RESULTS: The overall engraftment rate for PDXs from patients with non-small cell lung cancer was 34%. Squamous cell carcinomas had a higher engraftment rate (53%) compared with adenocarcinomas. Tumor samples from patients with stage II and stage III disease and from larger tumors were found to have relatively high engraftment rates. Patients whose tumors successfully engrafted had worse overall survival, particularly those individuals with adenocarcinoma, stage III or stage IV disease, and moderately differentiated tumors. Lymphoma formation was one of the factors associated with engraftment failure. Human CD8-positive and CD20-positive cells were detected in residual samples of tumor tissue that failed to generate a PDX at 1 year after implantation. Human immunoglobulin G was detected in the plasma of mice that did not have PDX growth at 14 months after implantation. CONCLUSIONS: The results of the current study indicate that the characteristics of cancer cells and the tumor immune microenvironment in primary tumors both can affect engraftment of a primary tumor sample.

Compartment syndrome of the foot associated with a delayed presentation of acute limb ischemia.

Compartment syndrome of the leg is a well-recognized complication known to follow urgent revascularization done for acute limb ischemia, but compartment syndrome of the foot has not been reported after the ischemia-reperfusion sequence. Herein we report a case of foot fasciotomy done for compartment syndrome that occurred after urgent revascularization. We suggest that foot fasciotomies should be considered in particular circumstances of acute lower leg ischemia, such as infrapopliteal thromboembolic events, prolonged ischemia, and persistent or worsening foot symptoms that follow revascularization and calf fasciotomies.

The impact of clinical, psychological, behavioral, social, and environmental factors on self-perceived symptom severity in a male cohort with intermittent claudication.

OBJECTIVE: To understand the relationship between self-perceived severity of intermittent claudication and various associated nonclinical factors, we examined how correlates in domains of physical activity (ie, clinical, psychological, behavioral, social, and environmental factors) relate to exertional limb symptoms. METHODS: A survey was administered to individuals with intermittent claudication during their initial outpatient assessment. The subjects' self-reported exertional limb symptom severity and classic-versus-atypical claudication classification was based on the Walking Impairment Questionnaire (WIQ) and San Diego Claudication Questionnaire (SDCQ), respectively. We evaluated psychosocial and environmental factors, osteoarthritis symptoms, health, behaviors, and beliefs. Logistic and linear regressions identified factors with a strong independent association with total WIQ scores and the SDCQs. RESULTS: A cohort of 102 subjects (99.0% male) was enrolled in the study. The median age was 65 years with a median ankle-brachial index of 0.69. Forty-three subjects (43%) had "typical" claudication per SDCQs. Individuals with atypical claudication were more likely to report higher Aberdeen Clinical Back Pain Questionnaire scores (odds ratio, 1.04; P = .04) and no depressive symptoms (odds ratio, 8.30; P = .03). Exertional limb symptom severity among the entire cohort was significantly associated with increasing osteoarthritis symptoms (P <.001), age (P = .02), a reserved personality (P = .008), and the belief that an exercise regimen would not improve symptoms (P = .005), self-perceived levels of boredom (P = .002), and the belief that exercise (P = .002) was the best way to improve symptoms were associated with decreased symptom severity. When restricted to those with atypical pain, significant factors associated with increasing exertional symptom severity included age greater than 60 years (P = .005), osteoarthritis (P = .02), alcohol use (P = .01), belief that exercise would not improve walking (P = .03), and difficulty walking around the neighborhood (P = .02). When restricted to those with classic claudication, significant factors associated with increasing exertional limb symptom severity included frequent pain or aching in the calves while walking or sitting (P = .03 [walking]; P = .01 [sitting]) and occasional morning joint stiffness (P = .007). Exertional limb symptom severity was also associated with high limitations at home (P = .003) and a belief that exercise would not improve walking (P = .005) among those with classic claudication. CONCLUSIONS: Symptom severity and type of pain are associated with a number of nonclinical factors. A multidomain approach, as indicated by the models above, would benefit the continuum of care for intermittent claudication, where management is integrated and coordinated among multiple lines of care.

Percutaneous intervention for carotid in-stent restenosis does not improve outcomes compared with nonoperative management.

BACKGROUND: The appropriateness of percutaneous intervention for moderate to severe carotid in-stent restenosis (C-ISR) is unclear. We therefore sought to compare stroke/death/myocardial infarction (MI) rates between percutaneous interventions and nonoperative management for ≥50% C-ISR. METHODS: We performed a single-center retrospective review of consecutive patients presenting with ≥50% C-ISR to the vascular surgery service. Demographics, comorbidities, and intraoperative and postoperative variables were obtained. The degree of stenosis was verified by review of digital subtraction or computed tomography angiograms. The primary outcome was stroke/death/MI after the diagnosis of ≥50% C-ISR. χ2, Kruskal-Wallis, and Kaplan-Meier analysis was used to quantify outcomes of the patients treated percutaneously vs nonoperatively. RESULTS: During a 13-year period, 59 patients (75 C-ISRs) presented with ≥50% C-ISRs (n = 58 male [98%]; n = 57 C-ISRs asymptomatic [76%]) with a median age of 67.5 years (62.8-74.6). The initial pathologic process underlying the original stent was atherosclerosis in 33 (70%), radiation induced in 10 (21%), prior carotid endarterectomy in 4 (9%), and unknown in 28 (37%). Forty C-ISRs underwent a percutaneous intervention (19 percutaneous angioplasty only [48%]; 21 repeated stent and percutaneous angioplasty [52%]). Median follow-up for the entire cohort was 948 days (283-2322) and similar between the intervention and nonintervention arms. There were no significant differences between the arms with respect to age (P = .16), medical comorbidities (P > .05), original stent type (P = .46), or clopidogrel use (P = .74). At 30 days, there was one stroke and subsequent death in the intervention arm and none in the nonintervention arm. During the follow-up period, a median of 1.0 procedure was required to maintain patency. By Kaplan-Meier analysis, there were no statistically significant differences between the intervention and nonintervention arms with respect to stroke/death/MI as a composite or any of the individual components at last follow-up (P = .82). Kaplan-Meier estimated patency was not significantly superior in the intervention vs the nonintervention arm (8.0 years ± 1.1 vs 5.3 years ± 0.7; P = .14). CONCLUSIONS: Over 13 years, percutaneous interventions for ≥50% C-ISR were safe and durable. However, interventions fail to improve long-term stroke/death/MI or patency rates relative to nonintervention. Intervention for C-ISR may not be necessary, although future appropriately powered, prospective trials will be necessary to confirm these findings and to determine the appropriateness of interventions for C-ISR.

Progression to stage 3 and 4 chronic kidney disease and risk factor stratification following endovascular aortic aneurysm repair.

BACKGROUND: Risk of progression to various stages of chronic kidney disease (CKD) after endovascular aortic aneurysm repair (EVAR) is unknown. This study estimates progression rates to stage 3 and 4 CKD after EVAR and identifies potential predictors for progression. METHODS: EVAR cases (2006-2012) were retrospectively reviewed. Freedom of progression to CKD was estimated using Kaplan-Meier analysis, and predictors for progression were identified using Cox proportional hazards model. RESULTS: Two hundred and twelve consecutive patients at a single academic institution underwent EVAR for infrarenal aneurysms. Estimated freedom from progression to stage 3 CKD was 80%, 76%, and 63% at 6, 12, and 18 months, respectively, and for stage 4, 97%, 96%, and 93% at 6, 12, and 18 months, respectively. Stage 3 CKD predictors of progression included age (odds ratio (OR): 1.106, p = 0.001), diabetes (OR: 3.052, p = 0.04), perioperative use of angiotensin converting enzyme inhibitors or angiotensin receptor blockers (OR: 3.249, p = 0.02), and operative blood loss (OR: 1.002, p < 0.01). Stage 4 predictors included preoperative hemoglobin (OR: 0.473, p = 0.04) and baseline renal function (OR: 0.928, p = 0.001). Intraoperative contrast administration did not impact CKD development. CONCLUSIONS: Progression to stage 3 CKD after EVAR occurs more frequently and at a higher rate compared with progression to stage 4. Different risk factors are associated with progression to each of those stages of CKD.

Common carotid artery peak systolic velocity ratio predicts high-grade common carotid stenosis.

OBJECTIVE: Screening for common carotid artery (CCA) stenosis with duplex ultrasound (DUS) velocity criteria alone can be limited by within-patient and between-patients hemodynamic variability. This study aimed to evaluate inter-CCA velocity ratio criteria to predict high-grade CCA stenosis. METHODS: This was a retrospective review of consecutive patients who underwent computed tomography angiography and DUS peak systolic velocity (PSV) measurements of bilateral CCAs, independently recorded, between 2008 and 2014. Patients with dampened CCA waveforms on DUS composed group B. The remainder without dampened waveforms constituted group A. Inter-CCA PSV ratios were calculated by dividing the higher CCA PSV by the lower one of the other side, so the ratios would always be ≥1. Ratios were subsequently paired with each respective unilateral CCA diameter stenosis and differential bilateral CCA diameter stenosis. A quadratic regression model was fitted to predict unilateral and differential stenosis. Receiver operating characteristic curve was used to determine optimal ratios for ≥50% and ≥80% CCA stenosis. The study excluded patients with carotid artery occlusion. RESULTS: From a total of 201 patients, 193 patients were included in group A and 8 in group B. Within group A, 31 patients had ≥50% unilateral stenosis and 17 had ≥50% differential stenosis. All stenoses ≥50% were identified on the same side with the higher PSV. Inter-CCA PSV ratio predicted ≥50% unilateral (r(2) = 0.536; P < .001) and differential stenosis (r(2) = 0.581; P < .001). In group B, all patients had ≥60% stenosis that was near or involved the vessel origin. An increasing inter-CCA PSV ratio showed a trend toward contralateral high-grade stenosis (r(2) = 0.596; P = .1). Receiver operating characteristic curves showed an optimal threshold CCA ratio ≥2.16 for ≥50% unilateral stenosis with 92% accuracy, 62% sensitivity, and 98% specificity (area under curve = 0.854; 95% confidence interval, 0.759-0.948) and a ratio ≥2.62 for ≥50% differential stenosis with 97% accuracy, 83% sensitivity, and 98% specificity (area under curve = 0.94; 95% confidence interval, 0.835-1). CONCLUSIONS: DUS-based CCA PSV ratio can accurately predict unilateral and differential high-grade CCA stenosis. Also, in patients with unilateral dampened waveforms, it implied contralateral severe proximal stenosis. This parameter should be further validated in prospective studies and may serve as an adjunct screening tool to detect high-grade CCA stenosis.

Comparison of domain-specific cognitive function after carotid endarterectomy and stenting.

BACKGROUND: Observational data indicate that carotid artery stenting (CAS) is associated with higher incidence of subclinical cerebral microemboli than carotid endarterectomy (CEA). We hypothesized that CEA would be associated with superior performance on detailed domain-specific cognitive testing compared with CAS. METHODS: Patients with >80% asymptomatic carotid artery stenosis were randomized to CEA or CAS with side of stenosis balanced across condition. A robust battery of tests was used to assess the cognitive domains of attention, memory, mood, visual-spatial skills, motor ability, processing speed, and executive functioning ≤10 days preoperatively and postoperatively at 6 weeks and 6 months. Tests were administered using standardized conditions and were scored by individuals blinded to treatment allocation. RESULTS: Baseline cognitive performance was similar between CAS (n = 29) and CEA (n = 31) groups (P > .05). Relative to baseline, verbal and visual memory and attention functions substantially improved in the CAS and CEA groups at 6 months (multiple cognitive tests achieved statistical significance). Compared with CEA, cognitive processing speed (Stroop Color test: 9.0 vs 7.3, P = .04; and Stroop Word test: 9.0 vs 7.4, P = .05) was superior in the CAS group at 6 weeks. Executive functioning (phonemic verbal fluency: 10.6 vs 8.4, P = .043) and motor function (Grooved Pegboard of nondominant extremity: 45.7 vs 38.9, P = .022) were also superior in the CAS group at 6 months. Tests of attention, memory, and visual-spatial skills were similar between CAS and CEA patients at 6 weeks and 6 months. CONCLUSIONS: Carotid revascularization improves memory and attention within the first 6 postoperative months. Compared with CEA, CAS produces improvements in cognitive processing speed, executive functioning, and motor function.

Validating common carotid stenosis by duplex ultrasound with carotid angiogram or computed tomography scan.

BACKGROUND: No consensus exists for duplex ultrasound criteria in the diagnosis of significant common carotid artery (CCA) stenosis. In general, peak systolic velocity (PSV) >150 cm/s with poststenotic turbulence indicates a stenosis >50%. The purpose of our study is to correlate CCA duplex velocities with angiographic findings of significant stenosis >60%. METHODS: We reviewed the carotid duplex records from 2008 to 2011 looking for patients with isolated CCA stenosis and no ipsilateral internal or contralateral carotid artery disease who received either a carotid angiogram or a computed tomography scan. We identified 25 patients who had significant CCA disease >60%. We also selected 74 controls without known CCA stenosis. We performed receiver operating characteristics analysis to correlate PSV and end-diastolic velocity (EDV) with angiographic stenosis >60%. The degree of stenosis was determined by measuring the luminal stenosis in comparison to the proximal normal CCA diameter. RESULTS: Most patients had a carotid angiogram (21/25), four only had a computed tomography angiography and four had both. Eighteen patients had history of neck radiation. The CCA PSV ≥250 cm/s had a sensitivity of 98.7% (81.5%-100%) and a specificity of 95.7% (92.0%-99.9%), CCA PSV ≥300 cm/s had a sensitivity of 90.9% (69.4%-98.4%) and a specificity of 98.7% (92.0%-99.9%). The CCA EDV ≥40 cm/s had a sensitivity of 95.5% (95% confidence interval of 75.1-99.8%) and specificity of 98.7% (92.0%-99.9%), EDV ≥60 cm/s had a sensitivity of 100% (75.1%-99.8%) and specificity of 87% (94.1-100%), and EDV ≥70 cm/s had a sensitivity of 86.4% (64.0%-96.4%) and specificity of 100% (94.1%-100%). The presence of both PSV <250 cm/s and EDV <60 cm/s had a 98.7% negative predictive value, and the presence of both PSV ≥250 cm/s and EDV ≥60 cm/s had 100% positive predictive value. CONCLUSIONS: Establishing CCA duplex criteria to screen patients with significant stenosis is crucial to identify those who will need further imaging modality or treatment. In our laboratory, CCA PSV ≥250 cm/s and EDV ≥60 cm/s are thresholds that can be used to identify significant (>60%) CCA stenosis with a high degree of accuracy.

Impact of cumulative intravascular contrast exposure on renal function in patients with occlusive and aneurysmal vascular disease.

OBJECTIVE: Patients with occlusive or aneurysmal vascular disease are repeatedly exposed to intravascular (IV) contrast for diagnostic or therapeutic purposes. We sought to determine the long-term impact of cumulative iodinated IV contrast exposure (CIVCE) on renal function; the latter was defined by means of National Kidney Foundation (NKF) criteria. METHODS: We performed a longitudinal study of consecutive patients without renal insufficiency at baseline (NFK stage I or II) who underwent interventions for arterial occlusive or aneurysmal disease. We collected detailed data on any IV iodinated contrast exposure (including diagnostic or therapeutic angiography, cardiac catheterization, IV pyelography, computed tomography with IV contrast, computed tomographic angiography); medication exposure throughout the observation period; comorbidities; and demographics. The primary end point was the development of renal failure (RF) (defined as NFK stage 4 or 5). Analysis was performed with the use of a shared frailty model with clustering at the patient level. RESULTS: Patients (n = 1274) had a mean follow-up of 5.8 (range, 2.2-14) years. In the multivariate model with RF as the dependent variable and after adjusting for the statistically significant covariates of baseline renal function (hazard ratio [HR], 0.95; P < .001), diabetes (HR, 1.8; P = .007), use of an angiotensin-converting enzyme inhibitor (HR, 0.63; P = .03), use of antiplatelets (HR, 0.5; P = .01), cumulative number of open vascular operations performed (HR, 1.2; P = .001), and congestive heart failure (HR, 3.2; P < .001), CIVCE remained an independent predictor for RF development (HR, 1.1; P < .001). In the multivariate survival analysis model and after adjusting for the statistically significant covariates of perioperative myocardial infarction (HR, 3.9; P < .001), age at entry in the cohort (HR, 1.05; P = .035), total number of open operations (HR, 1.51; P < .001), and serum albumin (HR, 0.47; P < .001), CIVCE was an independent predictor of death (HR, 1.07; P < .001). CONCLUSIONS: Cumulative IV contrast exposure is an independent predictor of RF and death in patients with occlusive and aneurysmal vascular disease.

Preliminary experiences with early primary closure of foot wounds after lower extremity revascularization.

BACKGROUND: The costs associated with local wound care after revascularization can be significant, and it has been suggested that early closure or healing of foot wounds can be a source of cost savings. We sought to determine the safety and effectiveness of attempts to primarily close chronic foot wounds early after revascularization. METHODS: We performed a single-center 1-year review of patients who underwent primary wound closure during the same hospitalization as revascularization. RESULTS: Seven patients underwent an attempt at early primary wound closure. Most (71%) were diabetic. The wounds were primarily closed at a median of 6 days after revascularization (range 3-8 days). The limb-salvage rate at 6 months was 86%. Four patients remained completely healed with primary closure. One healed secondarily with wound care, and 2 required major amputation. Wound-closure techniques included the use of toe/forefoot amputations, skin grafting, and local flaps. CONCLUSIONS: Early primary closure after revascularization may be a safe technique to consider for carefully selected foot wounds without ongoing soft tissue infection.

Short- and midterm results of iliac artery stenting for flush occlusion with the assistance of an occlusive contralateral iliac artery balloon.

BACKGROUND: Endovascular treatment of flush iliac artery occlusion remains a challenge and is most often performed using open surgery. We report the outcomes of 10 cases that were successfully recanalized endovascularly with the assistance of a contralateral occlusive balloon. METHODS: A retrospective review of patients undergoing iliac artery stenting was performed at a single institution. Technical success, short- and midterm patency, and 30-day complications are reported. RESULTS: Ten patients were identified. Technical success was 100% when a brachial approach was used. Retrograde recanalization was attempted in 3 cases. Reentry into the aorta could not be achieved in 1 case. The aorta was entered above the inferior mesenteric artery (IMA) in the other 2 cases, and the decision was made to attempt a brachial approach to avoid stenting above the IMA. There were no dissections or perforations. Two patients developed brachial access complications, but only 1 required operative repair for a pseudoaneurysm. Nine patients (90%) remained patent at a mean follow-up of 14.6 months (range 9-24 months). One patient presented 9 months later with iliac artery stent and lower extremity bypass thromboses, which resulted in an amputation. There were no deaths in this series. CONCLUSIONS: Iliac stenting for flush iliac artery occlusion can be achieved with this technique with encouraging short- and midterm results and minimal morbidity.

Cost-effectiveness of revascularization for limb preservation in patients with marginal functional status.

BACKGROUND: Revascularization and limb salvage attempts are often offered to patients with foot wounds and chronic limb ischemia who are thought to be good-risk candidates, but some skepticism remains about the utility of these efforts for elderly patients with marginal functional status. We sought to determine whether limb preservation efforts in this population could be justified from a patient-centered, cost-effectiveness perspective. METHODS: A probabilistic Markov model was used to simulate the clinical outcomes, health utilities, and costs over a 10-year period with various management strategies. Clinical parameter estimates were obtained from previous clinical trials and large observational series. Cost estimates were obtained from cost literature and also a single-center study that reviewed total costs accumulated (including secondary amputations, wound care, outpatient nursing care, and nursing home costs). Cost (in 2011 U.S. dollars) per year of ambulation (with limb preservation or with a prosthesis after amputation) was the primary measure of cost-effectiveness. RESULTS: The total 10-year costs of revascularization--either endovascular or surgical--were lower than the costs of either local wound care alone or primary amputation. Revascularization strategies also produced more health benefits as measured in terms of years of ambulatory ability, years of limb salvage, or quality-adjusted life-years. In none of the scenarios modeled in deterministic sensitivity analyses did primary amputation prove to be cost-effective. CONCLUSIONS: Revascularization and limb preservation attempts appear less costly and provide more health benefits than wound care alone or primary amputation, even among patients with marginal functional status at baseline.

Predicting the learning curve and failures of total percutaneous endovascular aortic aneurysm repair.

INTRODUCTION: Percutaneous endovascular aneurysm repair (PEVAR) has been shown to be feasible; however, technical success is variable, reported to be between 46.2% and 100%. The objective of this study was to quantify the learning curve of the PEVAR closure technique and identify predictors of closure failure. METHODS: We reviewed patient- and procedure-related characteristics in 99 consecutive patients who underwent PEVAR over a 30-month period in a single academic institution. A suture-mediated closure device (Proglide or Prostar XL) was used. Forward stepwise logistic regression was used to investigate associations between the failure of the closure technique and a number of patient and operative characteristics. To ensure objective assessment of the learning curve, a time-dependent covariate measuring time in calendar quarters was introduced in the model. Poisson regression was used to model the trend of observed failure events of the percutaneous technique over time. RESULTS: Overall PEVAR technical success was 82%. Type of closure device (P<.35), patient's body mass index (P<.86), type of anesthesia (P<.95), femoral artery diameter (P<.09), femoral artery calcification (P<.56), and sheath size as measured in Fr (P<.17) did not correlate with closure failure rates. There was a strong trend for a decreasing number of failure events over time (P<.007). The average decrease in the odds of technical failure was 24% per calendar quarter. The predicted probability of closure failure decreased from 45% per patient at the time of the initiation of our PEVAR program to 5% per patient at the end of the 30-month period. There were two postoperative access-related complications that required surgical repair. Need for surgical cutdown in the event of closure failure prolonged the operative time by a mean of 45 minutes (P<.001). No groin infections were seen in the percutaneous group or the failed group. CONCLUSIONS: Technical failure can be reduced as the surgeon gains experience with the suture-mediated closure device utilized during PEVAR. Previous experience with the Proglide device does not seem to influence the learning curve.

Impact of intraoperative administration of local vancomycin on inguinal wound complications.

OBJECTIVE: Local vancomycin treatment has been shown to decrease sternal wound complication rates. Whether a similar effect can be achieved at other surgical sites is unknown. This study investigates the effect of local vancomycin on inguinal wound complication rates after vascular procedures. METHODS: Retrospective analysis was performed on 454 patients who underwent open aortofemoral or infrainguinal vascular procedures between 2006 and 2011. Patients received preoperative systemic antibiotics either alone (group A) or in conjunction with intraoperative wound application of vancomycin powder and irrigation (group B). Inguinal wound infection and dehiscence over a 30-day period were recorded. Fisher exact test and multivariate regression analyses were performed. RESULTS: There were 211 patients in group A and 243 patients in group B. Both groups had similar demographics and operative characteristics. There was a small but statistically significant decrease in the 30-day incidence of overall wound infections (25.1% vs 17.2%; P = .049) for group B patients. This was primarily due to a decreased rate in superficial infections (18.9% vs 11.5%; P = .033). No significant difference in the incidence of deep wound infections (6.1% vs 5.7%; P = .692) or overall dehiscence rates (22.2% vs 17.7%; P = .239) was detected. On multivariate analysis, history of chronic obstructive pulmonary disease and increased body mass index significantly increased risk of both infection and dehiscence. Medically optimized coronary artery disease was associated with less risk for dehiscence. CONCLUSIONS: Addition of intraoperative local vancomycin did not improve the rates of inguinal wound dehiscence or deep infections but had a positive impact on superficial wound infections.

Impact of postoperative nadir hemoglobin and blood transfusion on outcomes after operations for atherosclerotic vascular disease.

OBJECTIVE: Controversy surrounds the topic of transfusion policy after noncardiac operations. This study assessed the combined impact of postoperative nadir hemoglobin (nHb) levels and blood transfusion on adverse events after open surgical intervention in patients who undergo operative intervention for atherosclerotic vascular disease. METHODS: Consecutive patients who underwent peripheral arterial disease (PAD)-related operations were balanced on baseline characteristics by inverse weighting on propensity score calculated as their probability to have nHb greater than 10 gm/dL on the basis of operation type, demographics, and comorbidities, including the revised cardiac risk index. A multivariate generalized estimating equation analysis was performed to investigate associations between nHb, transfusion, and a composite outcome of perioperative death and myocardial infarction. Logistic and Cox proportional hazards regressions were used to assess the impact of nHb and transfusion on respiratory and wound complications; and a composite end point (CE) of death, myocardial infarction during a 2-year follow-up. Level of statistical significance was set at alpha of 0.0125 to adjust for the increased probability of type I error attributable to multiple comparisons. RESULTS: The analysis cohort included 880 patients (1074 operations). After adjusting for nHb level, the number of units transfused was not associated with the perioperative occurrence of the CE (odds ratio [OR], 1.13; P = .025). Adjusted for the number of units transfused, nHb had no impact on the perioperative CE (OR, 0.62; P = .22). An interaction term between transfusion and nHb level remained nonsignificant (P = .312), indicating that the impact of blood transfusion was the same regardless of the nHb level. Perioperative respiratory complications were more likely in patients receiving transfusions (OR, 1.22; P = .009), and perioperative wound infections were less common in patients with nHb >10 gm/dL (OR, 0.65; P = .01). During an average follow-up of 24 months, transfused patients were more likely to develop the CE (hazard ratio [HR], 1.15, P = .009), whereas nHb level did not impact the long-term adverse event rate (HR, 0.78; P = .373). The above associations persisted even after adjusting the Cox regression model for the occurrence of perioperative cardiac events. CONCLUSIONS: Although nHb less than 10 gm/dL is not associated with death or ACS after PAD-related operations, maintaining nHb greater than 10 gm/dL appears to decrease the risk of wound infection. Blood transfusion is associated with increased risk of perioperative respiratory complications. Until a randomized trial settles this issue definitively, a restrictive transfusion strategy is justified in patients undergoing operations for atherosclerotic vascular disease.

An update on endovascular management of acute thoracic aortic disease and future directions.

Thoracic endovascular aortic repair (TEVAR) has become an alternative treatment option for acute thoracic aortic disease. This review focuses on current endovascular treatment of acute thoracic aortic disease and future directions of TEVAR. TEVAR is a promising alternative approach to open surgery, with lower early mortality and morbidity rates, especially in high-risk cohorts. Furthermore, with accumulating experience and improving device technology and imaging modalities, TEVAR has become safer and has potential to expand treatment options to include ascending and arch pathologies.

Modeling anesthetic times. Predictors and implications for short-term outcomes.

BACKGROUND: Little is known about the predictors of anesthetic times and impact of anesthetic and operative times on patient outcomes. METHODS: We documented operative case length, anesthetic induction time length, and anesthetic recovery time length in 1713 consecutive patients who underwent elective vascular surgical interventions. We recorded patient and procedure-related characteristics that might influence the anesthetic time length, including a variable for possible July effect. Multivariate linear regression was used to model the length of anesthetic times. Multivariate logistic regression was used to model the impact of anesthetic and operative time lengths on a composite outcome of perioperative (30-d postoperative) death, myocardial infarction, cardiac arrhythmias, stroke, and congestive heart failure. RESULTS: Statistically significant predictors of anesthetic induction time included body mass index, anesthesia type, and procedure type. Statistically significant predictors of anesthetic recovery time included operative case length, procedure type, and anesthesia type. After adjusting for the statistically significant covariates of total blood transfusion, history of coronary artery disease, and procedure type, there was a trend for increased likelihood of the composite end point as a function of operative time (odds ratio, 1.14; 95% confidence interval, 0.97-1.33; P = 0.09), which did not reach statistical significance. Multivariate analysis showed no association between the anesthetic time and composite end point. CONCLUSIONS: Modeling individually anesthetic induction and recovery time on the basis of operative and anesthetic procedure characteristics is feasible. Anesthetic and operative times do not impact perioperative morbidity and mortality.

Risk factors and impact of proximal fixation on acute and chronic renal dysfunction after endovascular aortic aneurysm repair using glomerular filtration rate criteria.

BACKGROUND: The incidence of renal impairment relevant to proximal fixation of aortic endograft devices remains unclear. METHODS: Retrospective cohort of 208 consecutive patients that underwent EVAR from 2006 to 2011. Estimated glomerular filtration rate (eGFR) was based on MDRD study equation. Acute kidney injury (AKI) and chronic kidney disease (CKD) were classified with ADIQ/RIFLE criteria and National Kidney Foundation criteria, respectively. Kaplan-Meier curve was applied to evaluate progression to CKD. Multivariate regression model was fit to identify predictors for developing AKI and CKD. RESULTS: Suprarenal fixation group (SF) included 110 patients and infrarenal fixation group (IF) included 98 patients. Both groups had similar demographics, baseline eGFR, and renal-protection protocols. There was a trend for decreased use of contrast in IF group (median: 93.5 vs. 103 cc, P = 0.07). AKI occurred in 15% of patients in SF group and 19% of patients in IF group (RR: 1.24, P = 0.47). The freedom from progression to stage 3 or 4 CKD in the SF group was 0.76, 0.72, and 0.49 at 6, 12, and 18 months, respectively, while for IF group was 0.8, 0.73, and 0.68, respectively (P = 0.4). Increasing age (P = 0.07), lengthy procedures (P < 0.001), and baseline renal dysfunction (P < 0.001) were significant predictors for developing CKD. Contrast volume (P < 0.001) and ace-inhibitors (P = 0.07) were predictors for AKI. CONCLUSION: Proximal fixation type has no significant effect on both acute and chronic renal function. Identification of modifiable perioperative risk factors may be used to improve renal function outcomes.

A case report: Retrograde arterial embolization of locally-injected SpaceOAR hydrogel material into the right common iliac artery bifurcation.

Biodegradable hydrogel-based matrices are becoming more widely utilized for a variety of medical applications, including SpaceOAR which is a hydrogel injected into the recto-prostatic space under ultrasound guidance to protect the rectum during prostate radiation therapy. Although a greater number of these procedures are being performed, there are no case reports on the potential complications which may result. In this report, we present the first case of retrograde embolization of SpaceOAR hydrogel into the right common iliac artery during routine office administration, as well as subsequent interventional angiography, inpatient and outpatient management, and clinical and imaging results at 1.5-month patient follow-up.

Literature Review of Percutaneous Stenting for Palliative Treatment of Malignant Superior Vena Cava Syndrome (SVCS).

RATIONALE AND OBJECTIVES: To assess the efficacy and safety of percutaneous stenting for the palliative treatment of malignant superior vena cava syndrome (SVCS). METHODS AND MATERIALS: Literature review of retrospective studies was performed regarding direct procedural complications (fatal and non-fatal), clinical effectiveness, and patency rates (primary and secondary) of percutaneous transluminal stenting for the palliative treatment of malignant SVCS. Pooled rates and 95% confidence intervals were calculated for fatal complications, non-fatal complications, clinical effectiveness, primary patency, and secondary patency. Pooled rates were presented overall and by stent types (Wallstent, Nitinol stents, Steel stents and Stent Graft). Odds ratios and 95% confidence intervals were calculated to compare rates by stent type. RESULTS: Overall fatal complications rate was 1.46%, 95% CI [0.91 -2.23], non-fatal complications rate was 8.28%, 95% CI [6.91 -9.83], clinical effectiveness was 90.50%, 95% CI [88.86 -91.97], primary patency rate was 86.18%, 95% CI [84.06-88.12], secondary patency rate was 94.05 %, 95% CI [91.82 -95.82]. Primary patency rate of the Wallstent group was 83.38%, 95% CI [79.34 -86.90], and significantly higher for the Nitinol group 94.87%, 95% CI [87.40 -98.60], OR = 3.67, p = 0.01, and for the Stent Graft group 96.10%, 95% CI [89.00 -99.20], OR = 4.92, p = 0.01. Secondary patency rate for the Wallstent group was 93.33%, 95% CI [88.87 -96.40] and significantly lower for the Steel group 77.42%, 95% CI [58.90 -90.41], OR = 0.25, p = 0.01. CONCLUSION: Percutaneous stenting is a safe option for palliative treatment of patients with malignant SVCS with greater than 90% of patients experiencing immediate relief of symptoms, low rates of fatal complications (1.46%) and high patency rates (86.18% primary patency and 94.05% secondary patency).