Predictors of Ambulatory Status at 1 Year Following Major Lower Extremity Amputation.

Nearly 60,000 major lower extremity amputations (AKA/BKA) are performed annually in the United States. We created a simple risk score for predicting ambulation at 1 year following AKA/BKA. We queried the Vascular Quality Initiative amputation database for patients who underwent above-knee (AKA) or below-knee (BKA) amputation (2013-2018). The primary endpoint was ambulation at 1 year either independently or with assistance. The cohort was divided into 80% derivation and 20% validation. Using the derivation set, a multivariable model identified preoperatively available independent predictors of 1 year ambulation and an integer-based risk-score was created. Scores were calculated to assign patients to risk groups-low, medium, or high chance of being ambulatory at 1 year. Internal validation was performed by applying the risk score to the validation set. Of 8725 AKA/BKA, 2055 met inclusion criteria-excluded: 2644 nonambulatory prior to amputation, 3753 missing 1-year follow-up ambulatory status. The majority-n = 1366, 66% were BKAs. The indications were CLTI; 47%, ischemic tissue loss; 9%, ischemic rest pain; 35%, infection/neuropathic; 9%, acute limb ischemia. Ambulation at 1 year was higher for BKA than AKA: 67%, versus 50%, p < .0001. In the final prediction model, contralateral BKA/AKA was the strongest predictor of nonambulation. The score provided reasonable discrimination (C-statistic = 0.65) and was well calibrated (Hosmer-Lemeshow p = .24). Sixty-two percent of patients who were ambulatory preoperatively remained ambulatory at 1 year. An integer-based risk score can stratify patients according to chance of ambulation at 1 year after major amputation and may be useful for preoperative patient counseling and selection.

Initial single-center experience using Fiber Optic RealShape guidance in complex endovascular aortic repair.

OBJECTIVE: In the present study, we have described the technical success using Fiber Optic RealShape (FORS) endovascular guidance and its effects on the overall procedural time and radiation usage during complex endovascular aortic repair (EVAR). METHODS: Fenestrated and branched EVARs performed at a single center from 2017 to 2022 were prospectively studied. FORS-guided procedures were matched retrospectively 1:3 to non-FORS-guided procedures by the incorporated target arteries and body mass index. Technical success was defined as successful target vessel cannulation using FORS for the entirety of navigation (wire insertion to exchange for a stiff wire). The predictors of technical success were evaluated via logistic regression. The procedural times and radiation doses were compared between the matched cohorts using the Wilcoxon rank sum test. RESULTS: A total of 21 FORS-guided procedures were matched to 61 non-FORS-guided procedures. A total of 95 FORS cannulations were attempted (87 for the visceral target artery and 8 for the bifurcate gate). Technical success was achieved in 81 cannulations (85%); 15 (16%) were completed without the use of live fluoroscopy. The univariate predictors of FORS technical success included <50% target artery stenosis, <50% target artery calcification, and the target vessel attempted (P < .05 for each). FORS failures were attributed to device material properties in six cases, device failure in two cases, and the wire/catheter combination in six. The use of FORS guidance was associated with shorter median procedural and fluoroscopy times and a lower dose area product and air kerma (P ≤ .0001 for each). CONCLUSIONS: The results from our initial experience with FORS during complex EVAR, including our learning curve, has shown promise, with acceptable technical success and reductions in procedural times and radiation usage.

Successful implementation of a nurse-navigator-run program using natural language processing identifying patients with an abdominal aortic aneurysm.

BACKGROUND: Abdominal aortic aneurysms (AAA) are often identified incidentally on imaging studies. Patients and/or providers are frequently unaware of these AAA and the need for long-term follow-up. We sought to evaluate the outcome of a nurse-navigator-run AAA program that uses a natural language processing (NLP) algorithm applied to the electronic medical record (EMR) to identify patients with imaging report-identified AAA not being followed actively. METHODS: A commercially available AAA-specific NLP system was run on EMR data at a large, academic, tertiary hospital with an 11-year historical look back (January 1, 2010, to June 2, 2021), to identify and characterize AAA. Beginning June 3, 2021, a direct link between the NLP system and the EMR enabled for real-time review of imaging reports for new AAA cases. A nurse-navigator (1.0 full-time equivalent) used software filters to categorize AAA according to predefined metrics, including repair status and adherence to Society for Vascular Surgery imaging surveillance protocol. The nurse-navigator then interfaced with patients and providers to reestablish care for patients not being followed actively. The nurse-navigator characterized patients as case closed (eg, deceased, appropriate follow-up elsewhere, refuses follow-up), cases awaiting review, and cases reviewed and placed in ongoing surveillance using AAA-specific software. The primary outcome measures were yield of surveillance imaging performed or scheduled, new clinic visits, and AAA operations for patients not being followed actively. RESULTS: During the prospective study period (January 1, 2021, to December 30, 2021), 6,340,505 imaging reports were processed by the NLP. After filtering for studies likely to include abdominal aorta, 243,889 imaging reports were evaluated, resulting in the identification of 6495 patients with AAA. Of these, 2937 cases were reviewed and closed, 1183 were reviewed and placed in ongoing surveillance, and 2375 are awaiting review. When stratifying those reviewed and placed in ongoing surveillance by maximum aortic diameter, 258 were 2.5 to 3.4 cm, 163 were 3.5 to 3.9 cm, 213 were 4 to 5 cm, and 49 were larger than 5 cm; 36 were saccular, 86 previously underwent open repair, 274 previously underwent endovascular repair, and 104 were other. This process yielded 29 new patient clinic visits, 40 finalized imaging studies, 29 scheduled imaging studies, and 4 AAA operations in 3 patients among patients not being followed actively. CONCLUSIONS: The application of an AAA program leveraging NLP successfully identifies patients with AAA not receiving appropriate surveillance or counseling and repair. This program offers an opportunity to improve best practice-based care across a large health system.

Medical center reimbursement for vascular procedures has increased over time while professional reimbursement has declined.

OBJECTIVE: The United States healthcare system uses different methods for assigning medical center reimbursement (MCR) and professional reimbursement (PR) for clinical services. We hypothesized that PR has not increased proportionately to MCR for the same vascular services. METHODS: MCR and PR were compared for commonly performed inpatient and outpatient vascular procedures between 2012 and 2021. MCR was calculated using the Medicare inpatient prospective payment system and outpatient prospective payment system. MCR is based on the Centers for Medicare and Medicaid Services definition and criteria for comorbidities and the occurrence of complications; thus, changes in MCR were reported as a range based on the degree of comorbidities and complications using the Diagnosis Related Group. PR was calculated using the Medicare physician fee schedule, which assigns a numerical work relative value unit to each surgical service, with final compensation determined by an annually adjusted conversion factor to yield a final dollar amount. The expected reimbursement based on the observed inflation during the study period using the consumer price index was calculated and compared to the actual reimbursement. RESULTS: From 2012 to 2021, MCR for inpatient procedures increased 20% to 26% for carotid endarterectomy, 24% to 27% for femoral endarterectomy, 24% to 27% for femoropopliteal bypass with vein, 14% to 19% for thoracic endovascular aortic repair, and 15% for aortobifemoral bypass. During the same period, PR increased 3.3% for carotid endarterectomy but decreased for femoral endarterectomy (-5.0%), femoropopliteal bypass (-4.6%), thoracic endovascular aortic repair (-4.2%), and aortobifemoral bypass (-5.0%). Comparing the expected reimbursement, adjusted for inflation, to the actual reimbursement, PR experienced a 10% to 17% reduction but MCR outpaced inflation by 3.7% to 10%. For outpatient procedures, MCR increased 117% for tibial angioplasty, 24% for superficial femoral artery (SFA) stenting, 62% for tunneled dialysis catheter (TDC) insertion, and 24% for iliac stenting but decreased 0.43% for arteriovenous fistula (AVF) creation and 7.6% for radiofrequency ablation (RFA). PR increased 0.91% for SFA stenting but decreased for tibial angioplasty (-17%), AVF creation (-6.4%), TDC insertion (-7.1%), iliac stenting (-3.8%), and RFA (-22%). Comparing the expected reimbursement, adjusted for inflation, to the actual reimbursement, PR experienced a 13% to 32% reduction. In contrast, MCR outpaced inflation 7.5% to 88% for tibial angioplasty, SFA stenting, TDC insertion, and iliac stenting but experienced a reduction for AVF (-13%) and RFA (-19%). CONCLUSIONS: MCR for commonly performed vascular procedures has increased and outpaced inflation. In contrast, PR for these same services has decreased across all procedure types. This decrease in PR was exacerbated when adjusted for inflation. This inequity in the reimbursement methods between MCR and PR poses a threat to the viability of the physician workforce. Either changes to the reimbursement methods or a reallocation of reimbursement to physicians are imperative to sustain physician practices.

Hemoglobin A1c monitoring practices before lower extremity bypass in patients with diabetes vary broadly and do not predict outcomes.

OBJECTIVE: Hemoglobin A1c (HbA1c) is used as a marker of glycemic control, but the role of HbA1c before lower extremity bypass (LEB) in patients with diabetes remains unclear. We sought to characterize patients with diabetes undergoing LEB with and without HbA1c monitoring and to determine if HbA1c monitoring practices correlate with better outcomes. METHODS: The Vascular Quality Initiative was queried for all LEB in patients with diabetes (2010-2020). Patients with diabetes were characterized based on therapy: diet-controlled, noninsulin medication use, or insulin use. Glycemic control was characterized by preoperative HbA1c within 6 months of surgery: unknown control (no HbA1c), well-controlled (HbA1c <7%), poorly-controlled (HbA1c 7%-10%), and uncontrolled (HbA1c >10%). Centers with >5 LEB/y were stratified into terciles according to rate of HbA1c monitoring. The unadjusted associations between glycemic control and in-hospital major adverse limb events, major adverse cardiac events, and mortality were assessed with univariate methods. The independent association of center-level HbA1c monitoring with 5-year survival and 3-year amputation-free survival (AFS) was determined with Kaplan-Meier analyses and Cox regression modeling, adjusted for differences in patient characteristics and center volume. RESULTS: Of 16,092 patients with diabetes undergoing LEB, 4055 (25%) did not have a documented HbA1c. Insulin use was less common in no A1c (48%) and well-controlled diabetes (39%) compared with poorly controlled (67%) and uncontrolled diabetes (78%) (P < .01). In univariate analyses, glycemic control was not associated with differences for in-hospital major adverse limb events, major adverse cardiac events, or mortality. Of 162 centers, HbA1c monitoring practices varied widely (range: 12.5%-100% of LEB). The 3-year AFS and 5-year survival were worse in the highest monitoring tercile vs the lowest (73.6% vs 77.3%, P < .01, 72.1% vs 77.5%, P < .01, respectively). On multivariable analyses, centers in the highest tercile of monitoring had the greatest hazard of AFS (hazard ratio: 1.21, 95% confidence interval: 1.1-1.3, P < .001) and overall mortality (hazard ratio: 1.19, 95% confidence interval: 1.1-1.3, P < 0.001), compared with the centers in the lowest tercile of monitoring. CONCLUSIONS: Patients with diabetes and no preoperative HbA1c monitoring do not have worse LEB outcomes compared with those with HbA1c monitoring. Preoperative HbA1c monitoring varies widely, suggesting broad differences in practice and documentation. Centers with the highest rates of monitoring demonstrated inferior outcomes, likely due to other confounding unmeasured variables. These findings indicate that HbA1c monitoring before LEB, unto itself, should not be used as a measure of surgical quality.

Trends in General Surgery Operative Experience Obtained by Integrated Vascular Surgery Residents.

OBJECTIVE: When the integrated vascular surgery training pathway was introduced, training was comprised of nearly equal amounts of core general surgery and vascular surgery experience. However, specific requirements for case numbers or types were not defined. Over time, the time spent on core general surgery requirements has been reduced, most recently in 2018, from 24 to 18 months. We sought to determine trends in general surgery case volume and type over the past 10 years for vascular surgery residents. METHODS: We conducted a retrospective review of the Accreditation Council for Graduate Medical Education case log data for integrated vascular surgery graduates from 2012-2018. We evaluated trends in mean numbers of cases, categorized as general surgery open (GS-open), general surgery laparoscopic (GS-laparoscopic), vascular surgery open (VS-open), and vascular surgery endovascular (VS-endo). Cases were also categorized by anatomic region as head/neck, thoracic, or abdominal. RESULTS: The mean number of total head/neck, thoracic, or abdominal cases logged by graduating integrated vascular surgery trainees was 263.5. This total, as well as the proportion of general surgery cases (35%-38%, p = 0.99) has remained constant over time. The type of general surgery cases has changed significantly, with an upward trend in the mean number of GS-open cases and downward trend in mean GS-laparoscopic cases (GS-open p = 0.006, GS-laparoscopic p = 0.048). Among head/neck and thoracic subgroups, no significant changes were observed, while in the abdominal subgroup, there has been a significant increase in GS-open over time (p = 0.005). Additionally, the number of open vascular abdominal aortic cases has remained stable, with an average of 36.82 per graduating trainee per year. CONCLUSIONS: In the 10 years since the introduction of integrated vascular surgery programs, total case volume and proportion of general surgery cases have remained remarkably stable. The type of general surgery cases has shifted though, with a decrease in GS-laparoscopic cases, replaced primarily by open abdominal cases. These changes likely reflect integrated vascular residents actively seeking out these opportunities during their core rotations and a willingness by general surgery partners to provide these opportunities. At the program level, these data may help guide program directors' choices about the specific core rotations they incorporate into their curriculum. At the national level, this information may contribute to future discussions regarding the optimal number of core general surgery rotation requirements.

A review of acute limb ischemia in COVID-positive patients.

This literature review discusses the current evidence on acute limb ischemia (ALI) in patients with COVID-19. Throughout the pandemic, these patients have been at increased risk of arterial thrombotic events and subsequent mortality as a result of a hypercoagulable state. The exact mechanism of thrombosis is unknown; however arterial thrombosis may be due to invasion of endothelial cells via angiotensin-converting enzyme 2 (ACE2) receptors, endothelial injury from inflammation, or even free-floating aortic thrombus. Multiple studies have been performed evaluating the medical and surgical management of these patients; the decision to proceed with operative intervention is dependent on the patient's clinical status as it relates to COVID-19 and morbidity of that disease. The interventions afforded typically include anticoagulation in patients undergoing palliation; alternatively, thrombectomy (endovascular and open) is utilized in other patients. There is a high risk of rethrombosis, despite anticoagulation, given persistent endothelial injury from the virus. Postoperative mortality can be high in these patients.

Evolution of fenestrated/branched endovascular aortic aneurysm repair complexity and outcomes at an organized center for the treatment of complex aortic disease.

BACKGROUND: Fenestrated/branched endovascular aneurysm repair (F/BEVAR) volume has increased rapidly, with favorable outcomes at centers of excellence. We evaluated changes over time in F/BEVAR complexity and associated outcomes at a single-center complex aortic disease program. METHODS: Prospectively collected data of all F/BEVAR (definition: requiring ≥1 fenestration/branch), procedures performed in an institutional review board-approved registry and/or physician-sponsored investigational device exemption trial (IDE# G130210), were reviewed (11/2010-2/2019). Patients were stratified by surgery date into thirds: early experience, mid experience, and recent experience. Patient and operative characteristics, aneurysm morphology, device types, perioperative and midterm outcomes (survival, freedom from type I or III endoleak, target artery patency, freedom from reintervention), were compared across groups. RESULTS: For 252 consecutive F/BEVARs (early experience, n = 84, mid experience, n = 84, recent experience, n = 84), 194 (77%) company-manufactured custom-made devices, 11 (4.4%) company-manufactured off-the-shelf devices, and 47 (19%) physician-modified devices, were used to treat 5 (2.0%) common iliac, 97 (39%) juxtarenal, 31 (12%) pararenal, 116 (46%) thoracoabdominal, and 2 (0.8%) arch aneurysms. All patients had follow-up for 30-day events. The mean follow-up time for the entire cohort was 589 days (interquartile range, 149-813 days). On 1-year Kaplan-Meier analysis, survival was 88%, freedom from type I or III endoleak was 91%, and target vessel patency was 92%. When stratified by time period, significant differences included aneurysm extent (thoracoabdominal, 33% early experience, 40% mid experience, and 64% recent experience; P < .001) and target vessels per case (four-vessel case, 31% early experience, 39% mid experience, and 67% recent experience; P < .0001). There was no difference, but a trend toward improvement, in composite 30-day events (early experience, 39%; mid experience, 23%; recent experience, 27%; P = .05). On Kaplan-Meier analysis, there was no difference in survival (P = .19) or target artery patency (P = .6). There were differences in freedom from reintervention (P < .01) and from type I or III endoleak (P = .02), with more reinterventions in the early experience, and more endoleaks in the recent period. CONCLUSIONS: Despite increasing repair complexity, there has been no significant change in perioperative complications, overall survival, or target artery patency, with favorable outcomes overall. Type I or III endoleaks remain a significant limitation, with increased incidence as the number of branch arteries incorporated into the repairs has increased.

Effect of thoracoabdominal aortic aneurysm extent on outcomes in patients undergoing fenestrated/branched endovascular aneurysm repair.

OBJECTIVE: The outcomes after open repair of thoracoabdominal aneurysms (TAAAs) have been definitively demonstrated to worsen as the TAAA extent increases. However, the effect of TAAA extent on fenestrated/branched endovascular aneurysm repair (F/BEVAR) outcomes is unclear. We investigated the differences in outcomes of F/BEVAR according to the TAAA extent. METHODS: We reviewed a single-institution, prospectively maintained database of all F/BEVAR procedures performed in an institutional review board-approved registry and/or physician-sponsored Food and Drug Administration investigational device exemption trial (trial no. G130210). The patients were stratified into two groups: group 1, extensive (extent 1-3) TAAAs; and group 2, nonextensive (juxtarenal, pararenal, and extent 4-5) TAAAs. The perioperative outcomes were compared using the χ2 test. Kaplan-Meier analysis of 3-year survival, target artery patency, reintervention, type I or III endoleak, and branch instability (type Ic or III endoleak, loss of branch patency, target vessel stenosis >50%) was performed. Cox proportional hazards modeling was used to assess the independent effect of extensive TAAA on 1-year mortality. RESULTS: During the study period, 299 F/BEVAR procedures were performed for 87 extensive TAAAs (29%) and 212 nonextensive TAAAs (71%). Most repairs had used company-manufactured, custom-made devices (n = 241; 81%). Between the two groups, no perioperative differences were observed in myocardial infarction, stroke, acute kidney injury, dialysis, target artery occlusion, access site complication, or type I or III endoleak (P > .05 for all). The incidence of perioperative paraparesis was greater in the extensive TAAA group (8.1% vs 0.5%; P = .001). However, the incidence of long-term paralysis was equivalent (2.3% vs 0.5%; P = .20), with nearly all patients with paraparesis regaining ambulatory function. On Kaplan-Meier analysis, no differences in survival, target artery patency, or freedom from reintervention were observed at 3 years (P > .05 for all). Freedom from type I or III endoleak (P < .01) and freedom from branch instability (P < .01) were significantly worse in the extensive TAAA group. Cox proportional hazards modeling demonstrated that F/BEVAR for extensive TAAA was not associated with 1-year mortality (hazard ratio, 1.71; 95% confidence interval, 0.91-3.52; P = .13). CONCLUSIONS: Unlike open TAAA repair, the F/BEVAR outcomes were similar for extensive and nonextensive TAAAs. The differences in perioperative paraparesis, branch instability, and type I or III endoleak likely resulted from the increasing length of aortic coverage and number of target arteries involved. These findings suggest that high-volume centers performing F/BEVAR should expect comparable outcomes for extensive and nonextensive TAAA repair.

Financial implications of coronavirus disease 2019 on a tertiary academic vascular surgery practice.

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic has had an unprecedented impact on the healthcare system in the United States. The redistribution of resources and suspension of elective procedures and other services has resulted in financial stress across all service lines. The financial effects on the practice of vascular surgery have not yet been quantified. We hypothesized that vascular surgery divisions have experienced losses affecting the hospital and professional sides that will not be recoupable without significant productivity increases. METHODS: Administrative claims data for clinical services performed by the vascular surgery division at a tertiary medical center for March and April 2019 and for March and April 2020 were analyzed. These claims were separated into two categories: hospital claims (inpatient and outpatient) and professional claims (professional reimbursement for all services provided). Medicare reimbursement methods were used to assign financial value: diagnosis-related group for inpatient services, ambulatory payment classification for outpatient services, and the Medicare physician fee schedule for professional reimbursement and work relative value units (wRVUs). Reimbursements and productivity (wRVUs) were compared between the two periods. A financial model was created to determine the increase in future productivity over baseline required to mitigate the losses incurred during the pandemic. RESULTS: A total of 11,317 vascular surgery claims were reviewed. Hospital reimbursement during the pandemic decreased from $4,982,114 to $2,649,521 (-47%) overall (inpatient, from $3,505,775 to $2,128,133 [-39%]; outpatient, from $1,476,339 to $521,388 [-65%]) and professional reimbursement decreased from $933,897 to $430,967 (-54%) compared with the same period in 2019. Professional productivity as measured by wRVUs sustained a similar decline from 10,478 wRVUs to 5386 wRVUs (-51%). Modeling sensitivity analyses demonstrated that if a vascular division were able to increase inpatient and outpatient revenue to greater than prepandemic levels by 10%, 5%, or 3%, it would take 9, 19, or 31 months, respectively, for the hospital to recover their pandemic-associated losses. Similarly, professional reimbursement recovery would require 11, 20, or 36 months with corresponding increases in productivity. CONCLUSIONS: The COVID-19 pandemic has had profound and lasting effects on the world in terms of lives lost and financial hardships. The financial effects on vascular surgery divisions has resulted in losses ranging from 39% to 65% compared with the prepandemic period in the previous year. Because the complete mitigation of losses is not feasible in the short term, alternative and novel strategies are needed to financially sustain the vascular division and hospital during a prolonged recovery period.

Computed tomography angiography-derived area stenosis calculations overestimate degree of carotid stenosis compared with North American Symptomatic Carotid Endarterectomy Trial-derived diameter stenosis calculations.

OBJECTIVE: The degree of carotid artery stenosis, calculated using catheter-based angiography and the North American Symptomatic Carotid Endarterectomy Trial (NASCET) method, has been shown to predict the stroke risk in several, large, randomized controlled trials. In the present era, patients have been increasingly evaluated using computed tomography (CT) angiography (CTA) before carotid artery revascularization, especially as the use of transcarotid artery revascularization has increased. Interpretation of CTA findings regarding the degree of carotid stenosis has not been standardized, with both NASCET methods and the area stenosis used. We performed a single-institution, blinded, retrospective analysis of CTA studies using both the NASCET method and the CT-derived area stenosis to assess the concordance and discordance between the two methods when evaluating ≥70% and ≥80% stenosis. METHODS: The UMass Memorial Medical Center vascular laboratory database was queried for all carotid duplex ultrasound scans performed from 2008 to 2017. The included patients were limited to those with duplex-defined ≥70% stenosis (defined as a peak systolic velocity of ≥125 cm/s and an internal carotid artery/common carotid artery ratio of ≥4), and a correlative CTA study performed within 1 year of the duplex ultrasound examination. A blinded review of all correlative CTA studies using centerline measurements on a three-dimensional workstation (Aquarius iNtuition Viewer; Terarecon, Durham, NC) was performed to characterize the degree of carotid stenosis using the NASCET method and the area stenosis method. Patients were excluded if revascularization had been performed between the two imaging studies. RESULTS: Of the 37,204 carotid duplex ultrasound scans reviewed (performed from 2008 to 2017), 3480 arteries met the criteria for duplex ultrasound-defined ≥70% stenosis. A correlative CTA study within 1 year of the duplex ultrasound examination was identified in 460 arteries, of which 320 were adequate quality for blinded review. The median interval between the duplex ultrasound and CTA examinations was 9.5 days. Concordance between the area stenosis and NASCET methods was poor for both ≥70% (κ = 0.32) and ≥80% (κ = 0.25) stenosis. Of the 247 arteries considered to have ≥70% area stenosis, 127 (51.4%) were considered to have ≥70% stenosis using the NASCET method. Of the 169 arteries considered to have ≥80% area stenosis, 44 (26.0%) were considered to have ≥80% stenosis using the NASCET method. CONCLUSIONS: The area stenosis CTA calculations of carotid artery stenosis dramatically overestimated the degree of carotid stenosis compared with that calculated using the NASCET method. Given that stroke risk estimates have been determined from trials that used the NASCET method, the area stenosis method likely overestimates the risk of stroke. Therefore, area stenosis calculations could lead to unnecessary carotid revascularization procedures. This model highlights the need for standardized usage of the NASCET method when using CTA as the imaging modality to determine the threshold for carotid revascularization.

Vascular Surgeons Are Not Adequately Valued by Traditional Productivity Metrics.

BACKGROUND: Reimbursements for professional services performed by clinicians are under constant scrutiny. The value of a vascular surgeon's services as measured by work relative value units (wRVUs) and professional reimbursement has decreased for some of the most common procedures performed. Hospital reimbursements, however, often remain stable or increases. We sought to evaluate fistulagrams as a case study and hypothesized that while wRVUs and professional reimbursements decrease, hospital reimbursements for these services increased over the same time period. METHODS: Medicare 5% claims data were reviewed to identify all fistulagrams with or without angioplasty or stenting performed between 2015 and 2018 using current procedural terminology codes. Reimbursements were classified into 3 categories: medical center (reimbursements made to a hospital for a fistulagram performed as an outpatient procedure), professional (reimbursement for fistulagrams based on compensation for procedures: work RVUs, practice expense RVU, malpractice expense RVU), and office-based laboratory (OBL, reimbursement for fistulagrams performed in an OBL setting). Medicare's Physician Fee Schedule was used to calculate wRVU and professional reimbursement. Medicare's Hospital Outpatient Prospective Payment System-Ambulatory Payment Classification was used to calculate hospital outpatient reimbursement. RESULTS: From 2015 to 2018, we identified 1,326,993 fistulagrams. During this study period, vascular surgeons experienced a 25% increase in market share for diagnostic fistulagrams. Compared with 2015, total professional reimbursements from 2017 to 2018 for all fistulagram procedures decreased by 41% (-$10.3 million) while OBL reimbursement decreased 29% (-$42.5 million) and wRVU decreased 36%. During the same period, medical center reimbursement increased by 6.6% (+$14.1 million). CONCLUSIONS: Vascular surgeons' contribution to a hospital may not be accurately reflected through traditional RVU metrics alone. Vascular surgeons performed an increasing volume of fistulagram procedures while experiencing marked reductions in wRVU and reimbursement. Medical centers, on the other hand, experienced an overall increase in reimbursement during the same time period. This study highlights that professional reimbursements, taken in isolation and without consideration of medical center reimbursement, undervalues the services and contributions provided by vascular surgeons.

Managing central venous access during a health care crisis.

OBJECTIVE: During the COVID-19 pandemic, central venous access line teams were implemented at many hospitals throughout the world to provide access for critically ill patients. The objective of this study was to describe the structure, practice patterns, and outcomes of these vascular access teams during the COVID-19 pandemic. METHODS: We conducted a cross-sectional, self-reported study of central venous access line teams in hospitals afflicted with the COVID-19 pandemic. To participate in the study, hospitals were required to meet one of the following criteria: development of a formal plan for a central venous access line team during the pandemic; implementation of a central venous access line team during the pandemic; placement of central venous access by a designated practice group during the pandemic as part of routine clinical practice; or management of an iatrogenic complication related to central venous access in a patient with COVID-19. RESULTS: Participants from 60 hospitals in 13 countries contributed data to the study. Central venous line teams were most commonly composed of vascular surgery and general surgery attending physicians and trainees. Twenty sites had 2657 lines placed by their central venous access line team or designated practice group. During that time, there were 11 (0.4%) iatrogenic complications associated with central venous access procedures performed by the line team or group at those 20 sites. Triple lumen catheters, Cordis (Santa Clara, Calif) catheters, and nontunneled hemodialysis catheters were the most common types of central venous lines placed by the teams. Eight (14%) sites reported experience in placing central venous lines in prone, ventilated patients with COVID-19. A dedicated line cart was used by 35 (59%) of the hospitals. Less than 50% (24 [41%]) of the participating sites reported managing thrombosed central lines in COVID-19 patients. Twenty-three of the sites managed 48 iatrogenic complications in patients with COVID-19 (including complications caused by providers outside of the line team or designated practice group). CONCLUSIONS: Implementation of a dedicated central venous access line team during a pandemic or other health care crisis is a way by which physicians trained in central venous access can contribute their expertise to a stressed health care system. A line team composed of physicians with vascular skill sets provides relief to resource-constrained intensive care unit, ward, and emergency medicine teams with a low rate of iatrogenic complications relative to historical reports. We recommend that a plan for central venous access line team implementation be in place for future health care crises.

Fenestrated/Branched Endovascular Aortic Aneurysm Repair Using a Supraceliac Aortic Proximal Seal Zone Versus an Infraceliac Aortic Proximal Seal Zone.

BACKGROUND: Fenestrated/branched endovascular aneurysm repair (F/B-EVAR) achieves more extensive proximal seal than conventional infrarenal devices, thereby increasing aneurysm exclusion durability. Optimal seal zone length remains undefined. We assessed relative risks and benefits of extending the proximal seal above the celiac artery. METHODS: The prospective database of all complex endovascular aortic aneurysm repairs at a single institution (institutional review board-approved, physician-sponsored investigational device exemption trial, 10/2010-6/2017) was used to classify repairs according to the number of target visceral-renal arteries incorporated: 4-vessel versus <4-vessel. Comparisons of aneurysm characteristics, perioperative details, and postoperative complications were performed, stratified by repair type. One-year survival, target artery patency, freedom from type 1 or 3 endoleak, and freedom from reintervention were estimated with Kaplan-Meier analysis. RESULTS: Among 175 F/B-EVARs, 38% (n = 67) were 4-vessel and 62% (n = 108) were <4-vessel. Intraoperatively, there was no difference in mean contrast use (76 mL vs. 74 mL, P = non significant [NS]) or dose area product (63,428 mGy cm2 vs. 96,015 mGy cm2), but there was increased median procedure time (4.8 hr, interquartile range [IQR] = 4.1-5.8 versus 3.6 hr, IQR = 2.9-4.1, P < 0.0001) and mean operating room direct costs ($52,532, standard deviation [SD] = 18,640 versus $40,128, SD = 15,135, P < 0.0001) in 4-vessel repairs. There were no differences in mortality (1.9% vs. 4.5%), paraparesis (0% vs. 3.0%), or paralysis (0.9% vs. 0%), all P = NS. There were no differences in one-year survival, target artery patency, or freedom from reintervention. There was a lower 1-year freedom from type 1 or 3 endoleak with 4-vessel repairs (82% vs. 94%, log-rank P = 0.02), driven by an increased rate of type 3 endoleaks. Endoleak resolution after treatment was equivalent in both groups (4-vessel, 10 of 12, 83% resolved; <4-vessel, 7 of 7, 100% resolved, P = NS). CONCLUSIONS: With F/B-EVAR, utilization of a supraceliac seal zone, compared with an infraceliac seal zone, is associated with statistical differences in operative characteristics/resource utilization, but with negligible clinical significance. Further innovation to eliminate type 3 endoleaks at fenestrations/branches remains an unmet need. To achieve adequate F/B-EVAR proximal seal zone length, one should have a low threshold to incorporate the celiac artery.

Acute Limb Ischemia in a 26-Year-Old Man Presenting with an Idiopathic Thrombosed Popliteal Artery Aneurysm.

Popliteal artery aneurysms (PAAs) are the most common peripheral arterial aneurysms and develop almost exclusively (>90%) in men who have a history of tobacco abuse at an average age of 65 years. Most PAAs are caused by chronic inflammation secondary to atherosclerotic disease; other nondegenerative causes of PAAs include arterial trauma, infection, Behçet's disease, medial fibromuscular dysplasia, or popliteal artery entrapment. Few case reports have been published on idiopathic congenital PAAs. We report a case of a 26-year-old man who presented with progressive claudication and subsequent acute limb ischemia due to the thrombosis of a large idiopathic PAA. Our case demonstrates that the differential diagnosis of young adult or pediatric patients presenting with signs of acute limb ischemia or claudication should include a symptomatic PAA.

Impact of acute kidney injury on long-term outcomes after fenestrated and branched endovascular aortic aneurysm repair.

OBJECTIVE: Acute kidney injury (AKI) has been identified as a common complication after fenestrated and branched endovascular aneurysm repair (F/BEVAR), occurring in 5% to 29% of patients. Predictors of AKI and its impact on long-term outcomes remain unknown. We sought to identify independent predictors of AKI and its effect on long-term survival after F/BEVAR. METHODS: A single-institution retrospective review of all consecutive F/BEVAR procedures was performed (November 2010-September 2018). Data were collected prospectively through an Institutional Review Board-approved registry and a physician-sponsored investigational device exemption clinical trial (G130210). AKI was defined as a decrease in estimated glomerular filtration rate by >30% from baseline, within 30 days postoperatively. The cohort was stratified according to whether a patient experienced AKI. Demographics, operative details, perioperative complications, and length of stay between groups were compared. The primary outcome, long-term survival, was assessed with Kaplan-Meier analysis and Cox proportional hazards modeling. Independent predictors of AKI were identified using logistic regression. RESULTS: Among 219 consecutive F/BEVAR patients, AKI occurred in 41 patients (19%) and was the most common 30-day complication observed. Whereas preoperative creatinine concentration, estimated glomerular filtration rate, and target renal artery stenosis >50% did not predict AKI, the occurrence of intraoperative complications did correlate with AKI (37% vs 7.3%; P < .01). By 30 days, AKI resolved in 7 (17%) patients, persisted without need for dialysis in 26 (64%), and progressed to dialysis in 5 (12%); the remaining 3 (7%) patients died. Survival at 30 days was significantly lower in the AKI group (92.7% vs 98.9%; P = .047), and this difference persisted at 1 year (68% vs 87%; log-rank, P <.01) and 3 years (44% vs 60%; log-rank, P = .04). On multivariable modeling, AKI increased the hazard of death nearly twofold (hazard ratio, 1.92; 95% confidence interval [CI], 1.11-3.23; P = .019). Independent predictors of AKI on multivariable logistic regression were intraoperative complications (odds ratio, 4.10; 95% CI, 1.61-10.42; P < .01) and increased operating room time (odds ratio, 1.56; 95% CI, 1.22-2.00; P < .01). CONCLUSIONS: In our 8-year experience of F/BEVAR, AKI was the most common postoperative complication observed in nearly 20% of patients. AKI after F/BEVAR is associated with decreased short- and long-term survival. Whether AKI is causative or just associated with decreased survival remains to be elucidated. Further study is needed to determine whether the independent predictors of AKI, including intraoperative complications and operating room time, are generalizable across all centers performing F/BEVAR and to investigate how we might further mitigate this common and serious complication.

Imaging Obtained Up To 12 Months Preoperatively Is Adequate for Planning Fenestrated/Branched Endovascular Aortic Aneurysm Repair.

OBJECTIVES: Patients referred for fenestrated/branched endovascular aortic repair (F/BEVAR) often present with a previous computed tomography angiogram (CTA), but it is unknown how recent the CTA must be to ensure accurate F/BEVAR planning. We sought to determine whether anatomic planning parameters change significantly between a CTA used for F/BEVAR planning and a CTA obtained 6 to 12 months prior. METHODS: Two blinded observers reviewed preoperative CTAs from 21 patients who underwent F/BEVAR. Each patient had a "recent" scan obtained 0 to 6 months before F/BEVAR planning and a "prior" scan obtained 6 to 12 months before the "recent" CTA. Standard measurements included (1) target vessel separation distances, (2) target vessel origin clock position, and (3) proximal F/BEVAR device diameter. Clinically significant differences for target vessel separation distance, target vessel origin clock position, and proximal F/BEVAR device diameter were predefined as >5 mm, >30 minutes, and >4 mm, respectively. Differences between "recent"/"prior" CTA scans were examined by paired t test. RESULTS: Mean time interval between paired "recent"/"prior" CTAs was 8.0 months (standard deviation: ±1.7). Mean difference in paired "recent"/"prior" target vessel distance (relative to celiac artery [CA]) was 2.6 mm for the superior mesenteric artery (SMA), 2.5 mm for the right renal artery (RRA), and 3.3 mm for the left renal artery (LRA). Of the 21 paired "recent"/"prior" CTAs, clinically significant differences were observed in 2, 4, and 2 patients for SMA, RRA, and LRA target vessel distance, respectively. Target vessel clock position (SMA reference at 12:00) varied by 12 minutes for the CA, 13 minutes for the RRA, and 15 minutes for the LRA. One paired "recent"/"prior" CTA was found to have a clinically significant difference for the LRA. No clinically significant differences were observed for proximal device diameter. CONCLUSIONS: In patients who underwent successful F/BEVAR, measurement comparisons between CTAs obtained up to 1 year prior were minor and unlikely to yield clinically significant changes to F/BEVAR design.

Carotid Duplex Velocity Criteria Recommended by the Society of Radiologists in Ultrasound and Endorsed by the Intersocietal Accreditation Commission Lack Predictive Ability for Identifying High-Grade Carotid Artery Stenosis.

BACKGROUND: Carotid duplex is the first-line imaging modality for characterizing degree of carotid stenosis. The Intersocietal Accreditation Commission (IAC), in published guideline documents, has endorsed use of the Society of Radiologists in Ultrasound (SRU) criteria to characterize ≥70% stenosis: peak systolic velocity (PSV) ≥230 cm/s. We sought to perform a validation of the SRU criteria using computed tomography (CT) angiography as a gold standard imaging modality and to perform a sensitivity analysis to determine optimal velocity criteria for identifying ≥80% stenosis. METHODS: We queried all carotid duplex examinations performed at our institution between 2008 and 2017. Patients with ≥70% carotid stenosis, based on previous criteria, were identified. Of these patients, those who also had a CT angiogram of the neck within one year formed the study cohort. Patients who underwent carotid revascularization between the 2 imaging dates were excluded. Degree of stenosis, as reported from the CT angiogram, was considered the true degree of stenosis. Receiver operating characteristic (ROC) curves were generated to evaluate the SRU criteria and to identify the optimal discrimination threshold for high-grade carotid stenosis. RESULTS: Of 37,204 carotid duplex examinations, 3,478 arteries met criteria for ≥70% stenosis. Of these, 344 patients had a CT angiogram within 1 year of the carotid duplex (mean time between studies, 55 days, SD 6.5) and 240 (69.8%) were consistent with ≥80% carotid stenosis. The predictive ability of the SRU criteria to identify ≥70% stenosis was poor, with an area under the ROC curve (AUC) of 0.51. A sensitivity analysis to identify ≥80% stenosis demonstrated the optimal discrimination threshold to be PSV ≥450 cm/s or end diastolic velocity (EDV) ≥120 cm/s, with an AUC of 0.66. CONCLUSIONS: In this validation study, the SRU criteria, endorsed by the IAC, to identify ≥70% carotid stenosis had no predictive value. For detection of ≥80% stenosis, the optimal criteria are a PSV ≥450 cm/s or EDV ≥120 cm/s. This study demonstrates the critical importance of carotid duplex examination validation.

Loss to follow-up 1 year after lower extremity peripheral vascular intervention is associated with worse survival.

Loss to follow-up (LTF) has been associated with worse outcomes after procedures. We sought to identify differences in lower extremity peripheral vascular intervention (PVI) patients with and without LTF, and to determine if LTF impacted survival. Patients in the PVI registry of the Vascular Quality Initiative (VQI) were included (n = 39,342), where t-test and chi-squared analysis were used to compare those with and without LTF. Multivariable logistic regression was used to identify factors associated with LTF while Cox regression analysis was applied to compare survival among those with and without LTF. The overall 1-year follow-up rate was 91.6%. LTF patients were more often male, Hispanic, of black race, and had a higher rate of diabetes, coronary artery disease, congestive heart failure, and dialysis. LTF patients had a higher prevalence of critical limb ischemia, underwent popliteal or distal intervention, and were intervened upon urgently. There was also a higher rate of postoperative complications, and a lower rate of technical success for LTF patients. After controlling for center effects, the independent variables associated with LTF included male sex, age, diabetes, dialysis dependence, ASA class 3 or greater, as well as complications requiring admission. Preoperative aspirin, preadmission home living status, prior carotid intervention, and discharge aspirin were protective against LTF. Adjusted survival analysis showed decreased survival in LTF, with those returning face-to-face surviving longer than those with phone follow-up. Efforts should be focused on understanding these differences to improve follow-up rates and help improve overall survival.

Explantation of infected thoracic endovascular aortic repair.

Prosthetic graft infection is a rare and serious complication of thoracic endovascular aortic repair associated with high mortality and posing unique challenges for treatment. The prosthetic graft infection is often identified late as patients present with mild nonspecific symptoms. We describe the successful medical management and surgical explantation of an infected thoracic endograft with an aorta-bronchial fistula, using an inline reconstruction with an antibiotic-soaked synthetic graft. In this report, we provide an example of a patient with an infected thoracic endograft and how inline reconstruction combined with appropriate medical management is an acceptable treatment strategy.