Chun Li

RS06. Risk of Insulin-Dependent Diabetes Mellitus in Patients Undergoing Carotid Endarterectomy

the purpose of this study is to develop a score to predict the risk of stroke/ death after CAS. Methods:We analyzed the Vascular Quality Initiative dataset from 2009 to the present. Univariate andmultivariate methods were used to identify predictors associated with 30-day stroke/death. Logistic regression was performed and variable selection for the final model was made on backward stepwise selection to achieve model parsimony. This final model was validated by bootstrapping (1000 repetitions) and tested by calibration (Hosmer-Lemeshow) and discrimination (c-statistic). A risk score was made by converting regression coefficients for each predictor to integers from which probability (%) was calculated. Scores were grouped into five simplified categories. Results: We identified 11,479 patients who underwent CAS during the study period with a combined 30-day stroke/death rate of 3.8%. Patients who developed the outcome of 30-day stroke/death were older (median age, 75 years vs 72 years), more likely to be female (41.3% vs 35.8%), symptomatic (58% vs 40.1%), and diabetic (44.8% vs 37.4%), and less likely to be on statins (71.4% vs 81.8%) and antiplatelet agents (aspirin, 78.1% vs 86.8%; P2Y12-inhibitor, 61.8% vs 77.1%; all P < .05). The Table details the demographic variables, comorbidities, preoperative medication, and lesionspecific predictors that were analyzed. Independent predictors included in the final model were age, female gender, diabetes, coronary artery disease, chronic kidney disease, chronic obstructive pulmonary disease, symptomatic status, contralateral occlusion, restenotic lesion, preoperative statin use, and P2Y12-inhibitor use. The model had a c-statistic of 70.9%. The corresponding score for each predictor, risk of 30-day stroke/death and two examples are shown in the Fig. Conclusions: This study introduces an easy to use clinical tool for predicting stroke/death after CAS and will help surgeons and patients in weighing the risks versus the benefits of performing this procedure. In asymptomatic patients with high predicted stroke/death risk, medical management might be the safer option.

IP221. Updated Tibial TransAtlantic Inter-Society Consensus Classification System Fails to Show Improved Differentiation in Outcomes After Endovascular Intervention

specialists and vascular specialists formed the collaborative, developing guidelines and protocols; frontline nonspecialists performing amputations were added to the collaborative in 2015 to decrease the percentage of major amputation performed. Demographics of the patients and fiscal and amputation data were collected, and standard statistical methods were applied. Results: Query revealed 567 total amputations, of which 198 were major and 137 were repeated amputations. Demographics for the entire cohort demonstrated an average age of 56.2 years, 87% nonwhite, 70% indigent, 86% diabetic, and 8% requiring dialysis. Prevalence of smoking and hypertension decreased over time (P < .05) and was the only significant change in patient risk factors. Overall, the ratio of major/total amputations (Fig 1) decreased from 48% to 22%, becoming statistically significant (P < .05) after 2015. A statistically significant difference in total amputations per year was not discovered. Major amputation rates remained highest among uninsured patients (P < .05) compared with public and private insurance. No statistically significant change occurred in patient payer mix. No patient risk or fiscal factors were predictive of repeated amputation. Vascular surgeons performed 14% of amputations in the entire cohort. Population analysis (Fig 2) of the top 10 amputation-prevalent ZIP codes representing 28% of all amputations revealed annual income per person of

PC090. Risk Score for Groin Access Complication in Ultrasound-Guided Percutaneous Aortic Procedures

14,900, 34.2% black, 51.2% Hispanic, 59% employed, 32% uninsured, 37% public insurance, and 32% private insurance. Conclusions: In resource-limited environments, threatened limbs may be managed by specialist and nonspecialist providers who are frontline and greater in number. Inclusion of sparse specialists into only a limb salvage collaborative did not achieve major limb amputation prevention in this study, and only after inclusion of all providers performing amputation did a statistically significant shift from major to minor amputation occur. Further reduction of major and minor amputation may be challenging in this population, given the limitations in system and patient resources, and will likely require alternative paradigms to existing models.

PC064. The Effect of Three-dimensional Image Fusion on Radiation Exposure, Contrast Dose, and Procedural Times During Carotid Artery Stenting

Unadjusted 30-day mortality was 16% in extent 2, 26% in extent 3, 19% in extent 4 disease (P < .03 for overall heterogeneity; Fig and Table); extent 3 was different from extent 2 and extent 4 (P < .009) but extent 2 versus extent 4 were not different from each other (P 1⁄4 .44). Vascular disease risk-burden was significant independent predictor of 30-day mortality, and for each 1-point increase in burden score, the odds of 30-day mortality increased by 1.5 time (P < .0001). After adjustment for other risk factors,

IP059. Early and Late Costs of Endovascular Abdominal Aortic Aneurysm Repair From the Endurant Stent Graft System Post Approval Study (ENGAGE PAS)

TheEffectofThree-dimensional ImageFusionon Radiation Exposure, Contrast Dose, and Procedural Times During Carotid Artery Stenting Nicholas J. Swerdlow, Douglas W. Jones, Alexander B. Pothof, Thomas F. X. O’Donnell, Patric Liang, Chun Li, Mark C. Wyers, Marc L. Schermerhorn. Beth Israel Deaconess Medical Center, Boston, Mass; Boston Medical Center, Boston, Mass; University Medical Center Utrecht, Utrecht, The Netherlands

VESS27. Statin Intensity One Year After Revascularization for Chronic Limb-Threatening Ischemia Is Associated With Higher Long-Term Survival

Objective: Some patients with intact abdominal aortic aneurysm (iAAA) have consumption coagulopathy without definitive diagnosis of disseminated intravascular coagulation (DIC). The objective of this study was to reveal the clinical significance of such marginal coagulopathy (namely, pre-DIC) associated with iAAA. Methods: This was a retrospective study of patients who underwent open repair for iAAA at Asahi General Hospital between 2015 and 2017. Ruptured and infectious AAAs were excluded. DIC scoring system from the Japanese Ministry of Health and Welfare was used. This system considers platelet counts (3 points), levels of fibrin and fibrinogen degradation products (3 points), fibrinogen (2 points), and international normalized ratio of prothrombin time (2 points) as well as underlying diseases and clinical symptoms (total 13 points). A score of 7 points or more is diagnostic for DIC in this system. In this study, we definedmarginal coagulopathy as having 46 points. Patients’ background, aortic diameter, operation procedures, estimated blood loss, and intraoperative blood transfusion were compared with those of the control group (Japanese Ministry of Health and Welfare DIC score of 3 points). Results: Among 88 patients, 13 (15%) had marginal coagulopathy. No one fulfilled the criteria of DIC. Although age (83 6 4.0 vs 73 6 8.7; P < .0001), aortic diameter (6.3 6 1.2 cm vs 5.7 6 1.0 cm; P 1⁄4 .04), and chronic kidney disease (9 [69%] vs 21 [28%]; P 1⁄4 .009) were significantly different, sex, hypertension, diabetes, smoking history, cardiac disease, and cerebrovascular disease were comparable between the two groups. Surgical procedures (eg, straight or bifurcated grafting), time before clamp, clamping time, and total operation time were also not significantly different. However, the estimated blood loss (869 6 671 mL vs 529 6 405 mL; P 1⁄4 .01) and the rate of intraoperative transfusion (5 [38%] vs 3 [4%]; P 1⁄4 .001) were significantly higher in the marginal coagulopathy group. First day of ambulation, resumption of normal diet, postoperative complication, and postoperative hospital stay were not significantly different between the two groups. Conclusions: Although DIC associated with iAAA is rare, we revealed that marginal coagulopathy is found in 15% of patients undergoing open repair for iAAA. Marginal coagulopathy carries a higher risk for more blood loss during open surgery for iAAA.

Three-dimensional image fusion is associated with lower radiation exposure and shorter time to carotid cannulation during carotid artery stenting

Objective: Endovascular aneurysm repair (EVAR) has reduced perioperative mortality for patients undergoing abdominal aortic aneurysm (AAA) repair despite the increase in elective aneurysm repair for the elderly. However, Medicare will not cover screening for beneficiaries older than 75 years, and AAA treatment in this population depends on incidental detection. Thus, we risk stratified elderly patients undergoing elective AAA repair to identify a subset of elderly patients who would potentially benefit from an expanded screening policy. Methods: We reviewed all patients undergoing elective EVAR in the Vascular Quality Initiative between 2003 and 2017. We used the beta coefficients from Cox regression models to construct a risk model for 5-year survival in patients >75 years old. Results: We identified 26,967 patients undergoing elective EVAR, 11,351 (42%) of whom were >75 years old. Perioperative mortality for the entire cohort was 0.9% (75 years, 0.6%; >75 years, 1.4%; P < .01). Although perioperative mortality varied directly with age, it was only 2.1% in the oldest group of patients (>85 years old). Factors included in our risk model for 5year survival in the elderly included age, aortic diameter, smoking status, white race, body mass index, renal function, diabetes, congestive heart failure, statin use, anemia (hemoglobin level <10 mg/dL), chronic obstructive pulmonary disease, prior aortic surgery, and beta blocker use. Total point values were 0 to 21 and classified patients into four risk categories. The lowest risk group (0-4 points) included 21% of the patients older than 75 years, whose 5-year survival was 89%, equivalent to that of patients younger than 75 years. Less than 1% of patients older than 75 years fell into the highest risk category (15+ points), who experienced 50% 5-year survival (Fig). Five-year survival in the four risk categories was statistically significantly different (P < .001), with a Harrell C statistic of 0.71. Conclusions: Elective EVAR in the elderly is associated with acceptable perioperative mortality. Our risk score can be used to define optimal patients for expanded screening based on expected postoperative 5-year survival to justify removing this Medicare coverage restriction.

PC016. Outcomes After Routine Ultrasound Usage in Percutaneous Endovascular Aortic Aneurysm Repair

Objective Three‐dimensional (3D) image fusion is associated with lower radiation exposure, contrast agent dose, and operative time during endovascular abdominal aortic aneurysm repair. Therefore, we evaluated the impact of this technology on carotid artery stenting (CAS). Methods We identified consecutive CAS procedures from 2009 to 2017 and compared those performed with and without 3D image fusion. For image fusion, we created a 3D reconstruction of the aortic arch anatomy based on preoperative computed tomography or magnetic resonance angiography that we merged with two‐dimensional fluoroscopy, allowing 3D image overlay. We compared radiation exposure, fluoroscopy time, contrast agent dose, time to common carotid artery (CCA) cannulation, time from CCA cannulation to completion angiography, and total procedure time in procedures with and without image fusion. We also assessed rates of 30‐day stroke/death, in‐hospital and 30‐day stroke, and acute kidney injury. We used multivariable linear regression to adjust for patient and procedural characteristics and used these models to compute the marginal effects of image fusion compared with no image fusion. Results There were 46 patients who underwent CAS with a 3D image fusion system and 70 patients without. Patients undergoing CAS with image fusion experienced 31% lower radiation exposure compared with the control group (207 ± 23 mGy vs 300 ± 26 mGy, respectively; P < .01), shorter fluoroscopy time (21 ± 6 minutes vs 24 ± 8 minutes; P = .02), shorter time to carotid cannulation (21 ± 9 minutes vs 31 ± 8 minutes; P < .001), and shorter total procedure time (47 ± 13 minutes vs 54 ± 18 minutes; P = .03). There was no difference in contrast material volume, time from CCA cannulation to completion angiography, or total in‐room time. After multivariable adjustment, 3D image fusion remained associated with lower radiation dose, shorter fluoroscopy time, and shorter time to carotid cannulation (all P < .05). The rate of 30‐day stroke/death was 2.7% (three strokes and no deaths at 30 days), and the rate of acute kidney injury was 1.8%. Conclusions CAS with 3D image fusion was associated with lower radiation exposure and shorter time to CCA cannulation. These results represent the potential technical advantage gained with image fusion and add to the growing body of evidence demonstrating its impact on radiation exposure and operative times during complex endovascular procedures.

Endovascular aneurysm repair in patients over 75 is associated with excellent 5-year survival, which suggests benefit from expanded screening into this cohort

CI, Confidence interval; PEVAR, percutaneous endovascular aortic aneurysm repair; US, ultrasound. P # .05 is significant. Percent calculated based on all EVARs performed by center as the denominator. Fig. Percent percutaneous endovascular aortic aneurysm (PEVAR), successful bilateral percutaneous access (bPEVAR), and ultrasound usage in the Vascular Quality Initiative between 2015 and 2017. *Percent calculated based on all EVARs performed by center as denominator. Journal of Vascular Surgery Abstracts e177 Volume 67, Number 6

IP013. The Weekend Effect in Abdominal Aortic Aneurysm Repair

Background Endovascular aneurysm repair (EVAR) has decreased the perioperative mortality for patients undergoing abdominal aortic aneurysm repair and has increased the rates of elective aneurysm repair in the elderly. However, Medicare will not cover abdominal aortic aneurysm screening for beneficiaries over 75 years of age. Consequently, abdominal aortic aneurysm treatment in this population depends on incidental detection. Targeted coverage for screening in this population, however, might be beneficial for a subgroup of patients. Methods To identify a subset of elderly patients who would potentially benefit from an expanded screening policy, we reviewed all patients greater than 75 years old undergoing elective EVAR in the Vascular Quality Initiative between 2003 and 2016. We used Cox regression with multivariable fractional polynomials to construct a risk model for 5‐year survival in elderly patients to identify a subpopulation who might benefit the most from screening and performed internal validation using the bootstrapping technique. Results We identified 10,676 patients greater than 75 years old undergoing elective EVAR. Although perioperative mortality varied with age, it was only 2.1% in the oldest group of patients (>85 years). Significant predictors included in our final risk model for 5‐year survival in the elderly included age, aortic diameter, hemoglobin, current smoking, white race, body mass index, renal function, congestive heart failure, statin use, chronic obstructive pulmonary disease, and ejection fraction. The risk model produced risk scores ranging from a possible −2 to 33. The mean and median risk score were 6.9 and 6.0, respectively, with a right skew. We categorized the risk scores into four groups: −2 to 4 points, 5‐8 points, 9‐13 points, and more than 13 points, with associated 5‐year survivals of 88%, 79%, 68%, and 49%, respectively. The model showed adequate discrimination and calibration, with a C‐statistic of 0.69 and a calibration score of 0.99 (predicted 5‐year survival of 0.78 compared with an observed 5‐year survival of 0.77) and a Brier score of 0.15. Internal validation demonstrated an optimism‐corrected C‐statistic of 0.69 and a calibration slope of 1.0. Conclusions Elective EVAR in elderly patients chosen to undergo repair is associated with acceptable perioperative mortality. Our risk score can be used to define optimal patients for expanded screening into all but the highest risk group based on expected postoperative 5‐year survival to justify removing this Medicare coverage restriction.