Jennifer Ellis

Aortic anatomic severity grade correlates with resource utilization

BACKGROUND Potential cost effectiveness of endovascular aneurysm repair (EVAR) compared with open aortic repair (OAR) is offset by the use of intraoperative adjuncts (components) or late reinterventions. Anatomic severity grade (ASG) can be used preoperatively to assess abdominal aortic aneurysms, and provide a quantitative measure of anatomic complexity. The hypothesis of this study is that ASG is directly related to the use of intraoperative adjuncts and cost of aortic repair. METHODS Patients who undergo elective OAR and EVAR for abdominal aortic aneurysms were identified over a consecutive 3-year period. ASG scores were calculated manually using three-dimensional reconstruction software by two blinded reviewers. Statistical analysis of cost data was performed using a log transformation. Regression analyses, with a continuous or dichotomous outcome, used a generalized estimating equations approach with the sandwich estimator, being robust with respect to deviations from model assumptions. RESULTS One hundred forty patients were identified for analysis, n = 33 OAR and n = 107 EVAR. The mean total cost (± standard deviation) for OAR was per thousand (k)

Cross-sectional area for the calculation of carotid artery stenosis on computed tomographic angiography.

38.3 ± 49.3, length of stay (LOS) 13.5 ± 14.2 days, ASG score 18.13 ± 3.78; for EVAR, mean total cost was k

Correlation of intravascular ultrasound and computed tomography scan measurements for placement of intravascular ultrasound-guided inferior vena cava filters

24.7 ± 13.0 (P = .016), LOS 3.0 ± 4.4 days (P = .012), ASG score 15.9 ± 4.13 (P = .010). In patients who underwent EVAR, 25.2% required intraoperative adjuncts, and analysis of this group revealed a mean total cost of k

Superior 3-Year Value of Open and Endovascular Repair of Abdominal Aortic Aneurysm with High-Volume Providers

31.5 ± 15.9, ASG score 18.48 ± 3.72, and LOS 3.9 ± 4.5, which were significantly greater compared with cases without adjunctive procedures. An ASG score of ≥15 correlated with an increased propensity for requirement of intraoperative adjuncts; odds ratio, 5.75 (95% confidence interval, 1.82-18.19). ASG >15 was also associated with chronic kidney disease, end stage renal disease, hypertension, female sex, increased cost, and use of adjunctive procedures. CONCLUSIONS Complex aneurysm anatomy correlates with increased total cost and need for adjunctive procedures during EVAR. Preoperative assessment with ASG scores can delineate patients at greater risk for increased resource use. Patient comorbid factors are associated with anatomic complexity defined according to ASG. A critical examination of the relationship between anatomic complexity and finances is required within the context of aggressive endovascular treatment strategies and shifts toward value-based reimbursement.

Volumetric Nephrogram Represents Renal Function and Complements Aortic Anatomic Severity Grade in Predicting EVAR Outcomes

OBJECTIVE The use of cross-sectional area (CSA) measurements obtained from computed tomographic angiography (CTA) for the calculation of carotid artery stenosis has been suggested but not yet validated in a large population. The objective of this study was to determine whether CTA-derived CSA measurements were able to predict carotid stenosis with a level of confidence similar to CTA-derived diameter measurements, using Strandness criteria applied to carotid duplex ultrasound (CDUS) as a surrogate for true stenosis. METHODS A retrospective review was conducted to identify patients who underwent both CDUS and CTA between 2000 and 2009. Percent stenosis was calculated using the North American Symptomatic Carotid Endarterectomy Trial (NASCET) formula with diameter measurements and again with CSA measurements. A nonparametric correlation coefficient was calculated to detect correlation between the two groups. Two-dimensional receiver-operating characteristic curves with corresponding area under the curve (AUC) statistics were generated for >50% stenosis and >80% stenosis. Three-dimensional receiver-operating characteristic plots with corresponding volume under the surface (VUS) statistics were generated to measure the comparative accuracy of diameter-based and CSA-based stenosis for <50%, 50%-79%, and >80% stenosis. RESULTS A total of 575 vessels in 313 patients were included in the study. Spearmans correlation coefficient between diameter and CSA-derived stenosis was ρ = 0.938 (95% confidence interval [CI], 0.927-0.947; P < .0001). For diameter-derived stenosis, AUC was 0.905 (95% CI, 0.878-0.932; P < .0001) for >50% stenosis and 0.950 (95% CI, 0.928-0.972; P < .0001) for 80%-99% stenosis. For CSA-derived percent stenosis, the AUC was 0.908 (95% CI, 0.882-0.935; P < .0001) for >50% stenosis and 0.935 (95% CI, 0.908-0.961; P < .0001) for 80%-99%. The nonparametric estimate for VUS in the diameter-based stenosis group was 0.761, whereas in the CSA-based group, the VUS was 0.735. The difference between VUS was 0.026 (95% CI, -0.022 and 0.077; P = .318). CONCLUSIONS These data support the use of CTA as an accurate method of calculating carotid artery stenosis based on agreement with Strandness criteria applied to CDUS velocities. When additional imaging beyond CDUS is necessary, we report no significant difference between diameter and CSA measurements obtained from CTA for preoperative evaluation of carotid disease.

Aspirin use is associated with decreased radiologically-determined thrombus sac volume in abdominal aortic aneurysms

OBJECTIVE The single puncture intravascular ultrasound (IVUS)-guided bedside placement of inferior vena cava (IVC) filters has been shown to be an effective technique. The major disadvantage of this procedure is a steep learning curve that can lead to an increased risk of filter malposition. In an effort to increase the safety and efficacy of IVUS-guided bedside IVC filter placement, we proposed that preoperative planning could reduce the incidence of IVUS-guided filter malpositions. As a first step, we examined the correlation between preoperative abdominal computed tomography (CT) scan measurements and intraprocedural IVUS derived measurements of vena cava anatomy and its surrounding structures. As a second step, we attempted to determine the safety of this protocol by assessing the incidence of malposition. METHODS A retrospective review of prospectively collected data was performed on all patients receiving bedside IVUS-guided filters from July 1, 2010 to August 31, 2011. Measurements of the IVC length from the atrial-IVC junction to the midportion of the crossing right renal artery, the lowest renal vein, and iliac vein confluence were obtained prior to IVC filter placement by both CT-based measurement, as well as intraprocedural IVUS pullback lengths. Regression analysis (significant for P < .05) was used to determine the correlation between these imaging modalities. RESULTS Forty-six patients had adequate CT scans available to perform the analysis and were candidates for bedside IVUS-guided IVC filter placement. All IVUS-guided filters were placed using a single puncture technique with the Cook Celect Filter. This study found there was a close correlation between IVUS and CT derived measurements of the right atrium to right renal artery distance, lowest renal vein distance, and iliac confluence distance. In addition, we found that the IVUS distances from the atrial-IVC junction to the right renal artery and lowest renal vein were statistically similar. Nine patients had 10 vascular anatomic variations, all identified by both IVUS and CT. There were no complications or malpositions of IVC filters using this protocol. CONCLUSIONS These data suggest that IVUS pullback measurements from the right atrium used in combination with preprocedure CT derived measurements of the distance from the right atrium to the lowest renal vein and iliac vein confluence provide an accurate roadmap for the placement of bedside IVC filters under IVUS guidance. We provide a method for organizing this information in a preplanning document to aid this procedure. We suggest this easily employed technique be more fully utilized to help decrease the incidence of malpositioned filters using single puncture IVUS guidance.

Superior 3-Year Value of Open and Endovascular Repair of Abdominal Aortic Aneurysm With High-Volume Providers

BACKGROUND Conflicting literature exists regarding resource utilization for cardiovascular care when stratified by provider volume. This study investigates the differences in value of abdominal aortic aneurysm (AAA) repair by high- and low-volume providers. The hypothesis of this study is that high-volume providers will provide superior value AAA repairs when compared to low-volume providers. METHODS Using the New York Statewide Planning and Research Cooperative System database and its linked death database, patients undergoing intact open and endovascular aneurysm repair (EVAR) were identified over a 10-year period. Charge data were normalized to year 2016 dollars and the data stratified by repair modality and annual surgeon volume. Univariate technique was used to compare the 2 groups over a 3-year follow-up period. RESULTS Nine hundred eleven surgeons performed open AAA repairs and 615 performed EVAR. For both repair modalities, and despite a patient population with more vascular risk factors, the cumulative adjusted charge for all aneurysm-related care was significantly less for high-volume providers than low-volume providers. The calculated 3-year value-patient life years per cumulative charge-was also superior for high-volume providers compared to low-volume providers. This difference in charge and value persisted after propensity score matching for race, sex, insurance status, and common vascular comorbidities including hypertension, dyslipidemia, and a history of smoking. CONCLUSIONS High-volume surgeons performing repair of aortic aneurysms provide superior value when compared to low-volume providers. The improved value margin is driven by both lower charge and improved survival, despite an increased incidence of cardiovascular comorbidities. This study adds support for the regionalization of care for patients with aortic aneurysm.

Aortoiliac Calcification Correlates With 5-Year Survival After Abdominal Aorta Aneurysm Repair

Introduction: Chronic kidney disease (CKD) is a predictor of poor outcomes for patients undergoing endovascular aortic aneurysm repair (EVAR). Anatomic severity grade (ASG) represents a quantitative mechanism for assessing anatomical suitability for endovascular aortic repair. Anatomic severity grade has been correlated with repair outcomes and resource utilization. The purpose of this study was to identify a novel renal perfusion metric as a way to assist ASG with predicting EVAR outcomes. Methods: Retrospective review of a prospectively maintained database identified elective infrarenal aortic aneurysm repair cases. Anatomic grading was undertaken by independent reviewers. Using volumetric software, kidney volume, and a novel measure of kidney functional volume, the volumetric nephrogram (VN) was recorded. Systematic evaluation of the relationship of kidney volume and VN to CKD and ASG was undertaken using linear regression and receiver–operator statistical tools. Results: A total of 386 cases with patient and anatomic data were identified and graded. Mean age was 72.9 ± 0.4 years. Renal volume <281 mL correlated with CKD (area under the curve [AUC] = .708; P ≤ .0001). Volumetric nephrogram <22.5 HU·L correlated with CKD (AUC = 0.764; P ≤ .0001). High (≥15) ASG scores correlated with both renal volume (AUC = .628; P ≤ .0001) and VN (AUC = .628; P ≤ .0001). Regression analysis demonstrated a strong, inverse relationship between ASG and VN (R 2 = .95). Conclusion: These data demonstrate that VN is a strong predictor of CKD in a large database of patients undergoing elective aneurysm repair. We demonstrate an inverse relationship between renal function and ASG that has not been previously described in the literature. Additionally, we have shown that VN complements ASG as a model of overall cardiovascular health and atherosclerotic burden. Outcomes in patients with poor renal function may be related to anatomical issues in addition to well-described systemic ramifications.

IP159. Inpatient Hemodialysis Access Surgery Results in Higher 30-Day and 2-Year Mortality Compared with Outpatient Surgery

Introduction Formation and renewal of intramural thrombus is associated with inflammation, and contributes to the complexity of aneurysm repair. Current cardiovascular pharmacotherapy includes several inflammatory modulators such as aspirin, statins, clopidogrel, and angiotensin-converting enzyme inhibitors. The purpose of our study was to investigate the effect of these inflammatory modulators on radiographically-determined thrombus sac volume. Methods Pre-operative computed tomography scans were reviewed in patients who underwent elective infrarenal aortic aneurysm repair. Thrombus sac volume was obtained using a Hounsfield unit restricted region growth algorithm. Co-morbid conditions such as diabetes mellitus and post-operative complications were evaluated compared to thrombus sac volume. Receiver–operator characteristic curves were generated for thrombus sac volume and patients on the various cardiovascular pharmacotherapies. Results A total of 266 patients (mean age = 72.6 ± 0.6 years; mean thrombus sac volume = 58.7 (34.4–89.0) cm3) were identified. Acetylsalicylic acid use was associated with a decreased thrombus sac volume ≤50 cm3 (AUC = 0.616, p = 0.013) whereas statins (p = 0.26), angiotensin-converting enzyme inhibitors (p = 0.46), and clopidogrel (p = 0.62) had no correlation to thrombus sac volume. Diabetes mellitus was not associated with thrombus sac volume (p = 0.31). Conclusion Acetylsalicylic acid use is associated with decreased thrombus sac volume in a patient population undergoing elective abdominal aortic aneurysms repair. The effect of acetylsalicylic acid over other anti-inflammatory and anti-platelet agents is possibly attributable to its distinct mechanism of cyclooxygenase-1 inhibition. Diabetes mellitus, a known correlate of aneurysm incidence, is not associated with thrombus burden. The potential to alter aneurysm thrombus volume, thereby affecting aneurysm morphology, may yield a more favorable aneurysmal repair.

Bundling of Reimbursement for Inferior Vena Cava Filter Placement Resulted in Significantly Decreased Utilization between 2012 and 2014

not measured in hours but was 5 to 7 days. The authors mention in the Discussion section that PMTmay not be as useful for chronic thrombus. One disadvantage of PMT is increased risk of distal emboli. In conclusion, I favor PMT for most cases of ALI for the aforementioned reasons: using this adjunct will get rid of clot quicker than CDT and will result in cost savings due to fewer returns to the endovascular suite and shorter hospital stays e assuming proper technique with PMT is used.