New predictors of complications in carotid body tumor resection.

OBJECTIVE: This study examined the relationship between two new variables, tumor distance to base of skull (DTBOS) and tumor volume, with complications of carotid body tumor (CBT) resection, including bleeding and cranial nerve injury. METHODS: Patients who underwent CBT resection between 2004 and 2014 were studied using a standardized, multi-institutional database. Demographic, perioperative, and outcomes data were collected. CBT measurements were determined from computed tomography, magnetic resonance imaging, and ultrasound examination. RESULTS: There were 356 CBTs resected in 332 patients (mean age, 51 years; 72% female); 32% were classified as Shamblin I, 43% as Shamblin II, and 23% as Shamblin III. The mean DTBOS was 3.3 cm (standard deviation [SD], 2.1; range, 0-10), and the mean tumor volume was 209.7 cm3 (SD, 266.7; range, 1.1-1642.0 cm3). The mean estimated blood loss (EBL) was 257 mL (SD, 426; range, 0-3500 mL). Twenty-four percent of patients had cranial nerve injuries. The most common cranial nerves injured were the hypoglossal (10%), vagus (11%), and superior laryngeal (5%) nerves. Both Shamblin grade and DTBOS were statistically significantly correlated with EBL of surgery and cranial nerve injuries, whereas tumor volume was statistically significantly correlated with EBL. The logistic model for predicting blood loss and cranial nerve injury with all three variables-Shamblin, DTBOS, and volume (R2 = 0.171, 0.221, respectively)-was superior to a model with Shamblin alone (R2 = 0.043, 0.091, respectively). After adjusting for Shamblin grade and volume, every 1-cm decrease in DTBOS was associated with 1.8 times increase in risk of >250 mL of blood loss (95% confidence interval, 1.25-2.55) and 1.5 times increased risk of cranial nerve injury (95% confidence interval, 1.19-1.92). CONCLUSIONS: This large study of CBTs demonstrates the value of preoperatively determining tumor dimensions and how far the tumor is located from the base of the skull. DTBOS and tumor volume, when used in combination with the Shamblin grade, better predict bleeding and cranial nerve injury risk. Furthermore, surgical resection before expansion toward the base of the skull reduces complications as every 1-cm decrease in the distance to the skull base results in 1.8 times increase in >250 mL of blood loss and 1.5 times increased risk of cranial nerve injury.

Real-World Performance of Paclitaxel Drug-Eluting Bare Metal Stenting (Zilver PTX) for the Treatment of Femoropopliteal Occlusive Disease.

BACKGROUND: The aim of this study was to evaluate the performance and predictors of stent failure of paclitaxel drug-eluting stents for the treatment of femoropopliteal disease. METHODS: A retrospective review of clinical and angiographic data was performed for patients treated for femoropopliteal disease with the Zilver PTX (Cook Medical, Bloomington, IN) stent by a single operator between 2012 and 2015 at a tertiary referral center. Clinical grading was determined by both Rutherford classification and the Society for Vascular Surgery's Wound, Ischemia, and Foot Infection (WIFi) scoring system, and lesions were classified anatomically by the TransAtlantic Intersociety Consensus (TASC) II criteria. Treated lesions included those with prior in-stent restenosis and long-segment disease. Primary clinical end points were stent failure, need for reintervention, and major adverse limb events (MALE). Kaplan-Meier methods and Cox proportional hazard models were used to evaluate factors affecting outcomes. RESULTS: Zilver PTX stents were placed in 52 limbs among 46 patients (71.1% male, mean age 72.6 years) with a median follow-up of 11.1 (range 1-26) months. Limbs were treated for life-disabling claudication in 76.9% and critical limb ischemia in 23.1%. Disease severity was highly variable, with 21 (40.4%) limbs with TASC C or D lesions and 16 (30.7%) treated for restenosis after prior endovascular treatment. During follow-up, 6 (12.7%) limbs experienced loss of stent patency (5 occlusions, one >50% restenosis). Four limbs underwent target lesion revascularization, 2 required open bypass, 2 underwent thrombolysis, and no patients required major amputation. Primary patency was 88.9%, 81.6%, and 81.6% at 6, 12, and 18 months, respectively. Treated lesion length (hazard ratio [HR] 4.99, 95% confidence interval [CI] 1.14-21.75) was the only independent predictor of patency loss. Freedom from target lesion revascularization at 6, 12, and 18 months was 94.2%, 87.8%, and 87.8%, respectively. Freedom from MALE (composite of thrombolysis, major amputation, and bypass operation) was 97.5%, 90.9%, and 79.6% at 6, 12, and 18 months, respectively. Chronic renal insufficiency was the only factor that trended toward increased risk of MALE (HR 9.92, 95% CI 0.86-113.35) within a multivariate model. CONCLUSIONS: Our real-world experience supports the continued use of the Zilver PTX for the treatment of both de novo lesions and lesions with prior endovascular revascularization in the femoropopliteal segment. Routine follow-up between 6 and 12 months postoperatively is essential for detecting early restenosis and guiding reintervention. Careful attention when treating complex lesions and long-segment disease remains important for selecting the optimal revascularization strategy for individual patients and optimizing stent patency.

Change in Aortic Neck Diameter after Endovascular Aortic Aneurysm Repair.

BACKGROUND: Implications of aortic neck dilatation following endovascular aneurysm repair (EVAR) are unclear. Previous studies are limited to comparisons of individual, early generation devices. We compared aortic neck dilatation among contemporary stent grafts. METHODS: We reviewed preoperative and postoperative computed tomographic angiograms for EVARs performed from 2008-2014. Images were analyzed using 3-dimensional centerline reconstructions. Aortic neck diameter was measured in orthogonal planes at and 10 mm below the lowest renal artery. Device type and main body graft diameter were obtained from operative reports. RESULTS: Eighty-six patients were analyzed with a median radiologic follow-up of 21.9 months (range: 4-64). Stent grants implanted included 26 Cook Zenith, 26 Gore Excluder, 22 Medtronic Endurant, 10 Endologix Powerlink, and 2 Trivascular Ovation devices. Mean device oversizing was 13.6 ± 11.5% and did not vary by device type (P = 0.54). Most patients (86.0%) experienced increases in aortic neck diameter during follow-up, with a mean increase of 1.3 ± 2.2 mm (5.9 ± 9.3%) and 3.3 ± 0.6 mm (8.9 ± 2.5%) at 30 day and latest follow-up scans, respectively. Repeated-measures analysis further demonstrated a significant increase in mean neck dilatation during follow-up (P < 0.001). Neck dilatation was not significantly different across different devices (P = 0.233). However, there was a moderate positive correlation between percent change in neck diameter and degree of oversizing, which was statistically significant (rs = 0.41, P < 0.001). Type Ia endoleak was observed in 2 patients and was associated with greater mean neck dilatation (8.8 ± 3.3 mm vs. 3.35 ± 2.71, P = 0.041). There was no relationship between changes in neck diameter and sac regression/expansion. CONCLUSIONS: Aortic neck diameter increases consistently over time following EVAR. The degree of neck dilatation correlates with degree of device oversize but not with device type.

Arterial cutdown reduces complications after brachial access for peripheral vascular intervention.

OBJECTIVE: Factors influencing risk for brachial access site complications after peripheral vascular intervention are poorly understood. We queried the Society for Vascular Surgery Vascular Quality Initiative to identify unique demographic and technical risks for such complications. METHODS: The Vascular Quality Initiative peripheral vascular intervention data files from years 2010 to 2014 were analyzed to compare puncture site complication rates and associations encountered with either brachial or femoral arterial access for peripheral vascular intervention. Procedures requiring multiple access sites were excluded. Complications were defined as wound hematoma or access vessel stenosis/occlusion. Univariate and hierarchical logistic regression was used to identify independent factors associated with site complications after brachial access. RESULTS: Of 44,634 eligible peripheral vascular intervention procedures, 732 (1.6%) were performed through brachial access. Brachial access was associated with an increased complication rate compared with femoral access (9.0% vs 3.3%; P < .001), including more hematomas (7.2% vs 3.0%; P < .001) and access site stenosis/occlusion (2.1% vs 0.4%; P < .001). On univariate analysis, factors associated with brachial access complications included age, female gender, and sheath size. Complications occurred less frequently after arterial cutdown (4.1%) compared with either ultrasound-guided (11.8%) or fluoroscopically guided percutaneous access (7.3%; P = .07 across all variables). Neither surgeons' overall peripheral vascular intervention experience nor prior experience with brachial access predicted likelihood of adverse events. By multivariate analysis, male gender (odds ratio [OR], 0.48; 95% confidence interval [CI], 0.28-0.84; P < .01) and arterial cutdown (OR, 0.25; 95% CI, 0.07-0.87; P = .04) were associated with significantly decreased risk for access complications. Larger sheath sizes (>5F) were associated with increased risk of complications (OR, 2.19; 95% CI, 1.07-4.49; P = .03). CONCLUSIONS: Brachial access for peripheral vascular intervention carries significantly increased risks for access site occlusion or hematoma formation. Arterial cutdown and smaller sheath diameters are associated with lower complication rates and thus should be considered when arm access is required.

A systematic review of assessment of skill acquisition and operative competency in vascular surgical training.

OBJECTIVE: The aim of this systematic review is to describe the literature and assessment tools evaluating vascular surgical operative performance that could potentially be used for the assessment of educational outcomes applicable to the Milestone Project and the Next Accreditation System. METHODS: A systematic review of PubMed/MEDLINE, EMBASE, PsycINFO, and key journals from 1985 to 2013 was performed to identify English-language articles describing assessment of vascular surgical skills and competence. Qualifying studies were abstracted for data concerning study aims, study and assessment setting, skills measured, and metrics used to determine competency. Strengths, weaknesses, and psychometric robustness of the assessment tools were determined. RESULTS: The literature search identified 617 citations. After title and abstract review, 65 articles were retrieved for full-text assessment and 48 articles were included in the final review. Twenty-nine articles assessed open vascular skills; 19, endovascular skills; six, nontechnical skills; and one, teamwork skills. The majority (84%) of studies were performed in a simulated environment, four (8%) were performed in the operating room, and the remaining three were performed in both a simulated environment and an operating room. Strengths and weaknesses of assessment tools were study and assessor dependent, with none applicable to all study scenarios or procedures. CONCLUSIONS: The literature describing assessment tools pertinent to vascular surgery is diverse. Existing assessment tools may be relevant to individual technical skill acquisition assessment; however, an operative assessment tool relevant to vascular/endovascular surgery and generalizable to the wide spectrum of technical and nontechnical skills pertinent to vascular surgery needs to be developed, validated, and implemented to allow the practical assessment of resident readiness to operate in an unsupervised setting.

Utility of direct angiosome revascularization and runoff scores in predicting outcomes in patients undergoing revascularization for critical limb ischemia.

OBJECTIVE: Both runoff scores and direct (DR) vs indirect revascularization (IR) according to pedal angiosomes have unclear impact on outcome for patients with critical limb ischemia (CLI). We compared DR vs IR and runoff scores in CLI patients undergoing infrapopliteal bypass for foot wounds. METHODS: Patients who had tibial/pedal bypass for a foot/ankle wound from 2005-2011 were identified and operations classified as DR or IR based on wound location and bypass target. A blinded observer reviewed angiograms for an intact pedal arch and calculated standard Society for Vascular Surgery (single tibial) and modified (composite tibial) runoff scores. Comorbidities, wound characteristics, wound healing, major amputation, and overall survival were determined. RESULTS: A total of 106 limbs were revascularized in 97 patients; 54 limbs had DR and 52 had IR, although only 36% of wounds corresponded to a single, distinct angiosome. Wound characteristics and comorbidities were similar between groups. Mean standard (7.9 vs 7.2; P = .001) and modified (22.2 vs 20.0; P = .02) runoff scores were worse (higher number indicates worse runoff) in the IR vs DR groups; 33% had a complete pedal arch. Complete wound healing (78% vs 46%; P = .001) and time to complete healing (99 vs 195 days; P = .002) were superior with DR vs IR but were not influenced by runoff score, modified runoff score or presence of complete plantar arch. In multivariate models controlling for runoff score, DR remained a significant predictor for wound healing (odds ratio, 2.9; 95% confidence interval, 1.1-7.4; P = .028) and reduced healing time (hazard ratio, 2.1; 95% confidence interval, 1.2-3.7; P = .012). Mean amputation-free survival (75 vs 71 months for DR vs IR; P = .82) and median survival (36 vs 33 months DR vs IR; P = .22) were not different for DR vs IR. CONCLUSIONS: DR according to pedal angiosomes provides more efficient wound healing, but is possible in only one-half of the patients and does not affect amputation-free or overall survival. DR is associated with improved runoff scores, but current runoff scores have little clinical utility in predicting outcomes in CLI patients.

Compliance with long-term surveillance recommendations following endovascular aneurysm repair or type B aortic dissection.

OBJECTIVE: Lifelong surveillance is recommended for both endovascular aneurysm repair and acute, uncomplicated type B thoracic aortic dissection, though compliance remains a significant challenge. We sought to determine factors associated with failure to obtain recommended surveillance. METHODS: Patients surviving to discharge who had endovascular repair of thoracic (thoracic endovascular aortic aneurysm repair [TEVAR]) or abdominal aortic aneurysms (endovascular aortic aneurysm repair [EVAR]) or medical management for type B dissections from 2004-2011 were reviewed. Primary end points were compliance with follow-up and need for reintervention. Comorbidities examined included coronary artery disease, congestive heart failure, hypertension, chronic obstructive pulmonary disease, diabetes, and chronic kidney disease. Socioeconomic factors examined were age, sex, distance from hospital, discharge destination (ie, home or skilled nursing facility), and insurance type. Endoleak and sac expansion were recorded, as were complications, including endograft migration, infection or thrombosis, and aneurysm degeneration. RESULTS: Two hundred four patients, median age 71.9 years, were identified; 171 had EVAR and 33 had type B dissection. EVAR patients included 45 thoracic, 100 abdominal, and 12 thoracoabdominal endografts, as well as 7 iliac artery aneurysm repairs and 7 proximal/distal graft extensions. Median follow-up was 28 ± 10.5 months. Overall, 56% were lost to follow-up, whereas 11% never returned for surveillance after initial hospitalization. Follow-up was compared for each of the comorbidities and socioeconomic factors; none were found to significantly affect follow-up. The known complication rate was 9.3% (n = 19), with reintervention performed in 14% of EVAR/TEVAR patients. Thirty-eight percent of medically managed patients with type B dissections eventually required surgical intervention. All-cause 5-year mortality was 27% as determined by the Social Security Death Index. CONCLUSIONS: Despite a significant rate of reintervention following EVAR, TEVAR, and type B dissection, long-term compliance with surveillance is limited. In addition, predicting who is at risk of being lost to follow-up remains difficult. If current recommendations for lifelong surveillance are to be followed, coordinated protocols are required to capture EVAR, TEVAR, and type B dissection patients to ensure optimal follow-up for these patients. However, the lack of survival benefit in those with complete follow-up suggests that further study is needed with regard to ideal duration of long-term follow-up.

Medical comorbidities but not interventions adversely affect survival in patients with intermittent claudication.

OBJECTIVE: Intermittent claudication (IC) is common and associated with decreased survival. While patients with IC infrequently progress to critical limb ischemia (CLI), many elect to pursue intervention initially or during follow-up. However, controversy exists as to whether intervention in patients with IC adversely impacts survival or limb salvage. The purpose of this study was to characterize patient demographics and comorbidities with respect to differences in survival and limb salvage among patients who elect no intervention (NI) vs those electing immediate intervention (II) or delayed intervention (DI) for IC. METHODS: Patients referred to a university practice for limb ischemia were identified via a query of the electronic medical record from 2007 to 2011. Patients with prior lower extremity interventions or CLI were excluded. IC patients were classified according to intervention: NI during follow-up, II, and DI. Patient demographics, Charlson morbidity index, survival, and reintervention rates were analyzed. RESULTS: A total of 262 of 1320 patients met inclusion criteria. Thirty patients with possible IC were believed to have nonarterial related symptoms. Study patients included 132 with NI, 62 with II, and 38 with DI. DI patients were younger and less frequently diabetic (median age, 65.5 years, 63.5 years, 58.0 years; P = .002; diabetes, 43.2%, 39.5%, 22.6%; P = .02 for NI, II, and DI, respectively). NI patients had higher Charlson comorbidity scores (P < .05). Hypertension, hyperlipidemia, and diabetes were associated with decreased survival in all groups (P < .05). Median survival was greatest for DI patients and least for NI patients (NI 92 months, II 95 months, DI 143 months; log-rank = .015). Primary patency of interventions at 1 and 5 years were equal for II and DI patients (1 year, II 80% vs DI 79%; 5 years, II 45% vs DI 50%; P = .9). Reintervention was common with rates similar between the II and DI groups (P > .05). Four of 38 DI patients required minor amputation for progression to CLI. There were no major amputations in any group. CONCLUSIONS: Progression to CLI is uncommon in IC. Survival of claudicants is decreased by diabetes, hypertension, and hyperlipidemia but not by intervention for IC. Reintervention is common in treated IC patients but no different among those undergoing II and DI. Intervention did not lead to major amputation. II or DI in IC patients does not affect survival or major amputation.

Isolated calf muscular vein thrombosis is associated with pulmonary embolism and a high incidence of additional ipsilateral and contralateral deep venous thrombosis.

OBJECTIVE: Little is known about the natural history of isolated gastrocnemial and soleal vein thrombosis (IGSVT), and recommendations for treatment and follow-up are therefore anecdotal. This study sought to determine the rates of venous thromboembolism (VTE) progression and resolution and the effect of antithrombotic therapy in patients with IGSVT. METHODS: A vascular laboratory database was queried from January 2002 to December 2006 to identify patients with duplex-diagnosed IGSVT and follow-up duplex scan studies. Duplex scan examinations were reviewed to determine rates of resolution and development of new ipsilateral and contralateral VTE. Records were reviewed for comorbid conditions, VTE risk factors, anticoagulation therapy, the effect of anticoagulation on resolution of IGSVT, and diagnosis of pulmonary embolism (PE) confirmed by computed tomographic angiography. RESULTS: Patients with at least one follow-up duplex scan study were included in our analysis. Sixty-five limbs with isolated IGSVT were identified in 57 patients with follow-up duplex scans (mean, 2.75 studies per patient; mean follow-up, 113 days). Twenty patients (35%) received therapeutic anticoagulation after the IGSVT diagnosis. There were seven PEs, two on the same day as initial IGSVT diagnosis, and two within 1 week of diagnosis. IGSVT resolution rates by Kaplan-Meier analysis at 1 and 3 months were 20% and 41%, respectively. Eleven patients (19%) developed additional ipsilateral deep venous thrombosis (DVT; three axial calf vein thromboses and five proximal DVT) or contralateral DVT (one axial calf vein thrombosis [CVT], one IGSVT, and one proximal DVT) during follow-up. Of the eight patients who developed additional ipsilateral DVT, five also developed concurrent contralateral DVT. Overall, 14% of patients developed contralateral DVT. Median time to development of additional DVT was 10 days. Therapeutic anticoagulation was associated with DVT resolution. However, VTE recurrence was not significantly affected by age, gender, anticoagulation, oral contraceptives, known hypercoagulable states, or comorbidities (smoking, cancer, trauma, postsurgical status, renal failure, hyperlipidemia, diabetes, or cardiopulmonary abnormalities; P > .05). CONCLUSIONS: Isolated calf muscular vein thrombosis is associated with PE and a significant incidence of VTE progression. Therapeutic anticoagulation is associated with DVT resolution, but its effect on VTE recurrence was not demonstrated. Untreated patients with IGSVT should receive follow-up bilateral lower extremity venous duplex scans within 10 days of diagnosis.

Results of routine shunting and patch closure during carotid endarterectomy.

BACKGROUND: The role of shunting and patching during carotid endarterectomy remains controversial. METHODS: This is a retrospective case series evaluating consecutive patients undergoing carotid endarterectomy with routine shunting and patching. The primary endpoints were perioperative stroke, arterial injury, and lesion recurrence by duplex. RESULTS: Of the 220 operations performed, 43% were for symptomatic disease. Successful shunt placement occurred in 98%, with no shunt-related injuries. There was 1 minor perioperative stroke and no major strokes. At a mean follow-up of 24 months (median = 12 months), there was 1 restenosis potentially related to shunt placement. The incidence of asymptomatic >50% stenosis in the patched segment was 8%. CONCLUSIONS: A combined policy of routine shunting and patching simplifies intraoperative decision making with results that rival or exceed those of trials in which their use was not standardized. Shunts need not be avoided because of concern of arterial injury.