Roan J. Glocker

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)

Adrenal artery aneurysm encountered during laparoscopic adrenalectomy for pheochromocytoma

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

Outcomes for critical limb ischemia are driven by lower extremity revascularization volume, not distance to hospital

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.

REHEARSAL Using Patient-Specific Simulation to Improve Endovascular Efficiency

Adrenal artery aneurysms are an extremely rare clinical entity. Only six previous case reports of adrenal artery aneurysms exist, all of which were discovered after rupture. Herein, we describe the discovery of an unruptured adrenal artery aneurysm found during laparoscopic adrenalectomy for pheochromocytoma.

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

Objective: The objective of this study was to identify relationships among geographic access to care, vascular procedure volume, limb preservation, and survival in patients diagnosed with critical limb ischemia (CLI). Methods: Using New York State administrative data from 2000 to 2013, we identified a patients first presentation with CLI defined by International Classification of Diseases, Ninth Revision diagnosis and procedure codes. Distance from the patients home to the index hospital was calculated using the centroids of the respective ZIP codes. A multivariable logistic regression model was employed to estimate the impact of distance, major lower extremity amputation (LEA) volume, and lower extremity revascularization (LER) volume on major amputation and 30‐day mortality. Volumes and distances were analyzed in quintiles. The farthest distance quintile and the highest procedure volume quintiles were used as references for generating odds ratios (ORs). Results: There were 49,576 patients identified with an initial presentation of CLI. The median age was 73 years, 35,829 (73.2%) had Medicare as a primary insurer, 11,395 (23.0%) had a major amputation, and 4249 (8.6%) died within 30 days of admission. Patients in the closest distance quintile were more likely to undergo amputation (OR, 1.53 [1.39‐1.68]; P < .0001). Patients who visited hospitals in the lowest LER volume quintile with at least one procedure per year faced higher 30‐day mortality rates (OR, 2.05 [1.67‐2.50]; P < .0001) and greater odds of amputation (OR, 9.94 [8.5‐11.63]; P < .0001). Patients who visited hospitals in the lowest LEA volume quintile had lower odds of 30‐day mortality (OR, 0.66 [0.50‐0.87]; P = .0033) and lower odds of amputation (OR, 0.180 [0.142‐0.227]; P < .0001). Conclusions: Rates of major amputation are inversely associated with distance from the index hospital, whereas rates of both major amputation and mortality are inversely associated with LER volume. Rates of major amputation and mortality are directly associated with LEA volume. We believe that unless it is otherwise contraindicated, these data support consideration for selective referral of CLI patients to high‐volume centers for LER regardless of distance. Within the context of value‐based health care delivery, policy supporting regionalization of CLI care into centers of excellence may improve outcomes for these patients.

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

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.

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

Objective: To determine whether rehearsal using patient-specific information loaded onto an endovascular simulator prior to carotid stenting improves procedural efficiency and outcomes. Methods: Patients scheduled for carotid artery stenting who had adequate preoperative computed tomography (CT) imaging were considered for enrollment. After obtaining informed consent, patients were randomized to control versus rehearsal groups. Those in the rehearsal group had their CT scans loaded into an endovascular simulator (Angio Mentor) followed by case rehearsal by the attending on the simulator within 24 hours prior to the procedure; control patients underwent routine carotid stenting without rehearsal. Contrast usage, fluoroscopy time, and timing of procedural steps were recorded by a blinded observer during the actual case to determine benefit. Results: Fifteen patients were enrolled, with 6 patients randomized to the rehearsal group and 9 to the control. All measures showed improvement in the rehearsal group: Mean contrast volume (59.2 vs 76.9 mL), fluoroscopy time (11.4 vs 19.4 minutes), overall operative time (31.9 vs 42.5 minutes), time to common carotid sheath placement (17.0 vs 23.3 minutes), and total carotid sheath dwell time (14.9 vs 19.2 minutes) were all lower (more favorable) in the rehearsal group. The study was terminated early due to the lack of simulator access, and all P values were thus greater than .05 due to the lack of power. No strokes or other adverse events occurred in either group. Conclusion: Case-specific simulator rehearsal using patient-specific imaging prior to carotid stenting is associated with numerically less contrast usage, operative time, and radiation exposure, although this study was underpowered.

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.