Decreasing prevalence of centers meeting the Society for Vascular Surgery abdominal aortic aneurysm guidelines in the United States.

OBJECTIVE: Based on data supporting a volume-outcome relationship in elective aortic aneurysm repair, the Society of Vascular Surgery (SVS) guidelines recommend that endovascular aortic repair (EVAR) be localized to centers that perform ≥10 operations annually and have a perioperative mortality and conversion-to-open rate of ≤2% and that open aortic repair (OAR) be localized to centers that perform ≥10 open aortic operations annually and have a perioperative mortality ≤5%. However, the number and distribution of centers meeting the SVS criteria remains unclear. This study aimed to estimate the temporal trends and geographic distribution of Centers Meeting the SVS Aortic Guidelines (CMAG) in the United States. METHODS: The SVS Vascular Quality Initiative was queried for all OAR, aortic bypasses, and EVAR from 2011 to 2019. Annual OAR and EVAR volume, 30-day elective operative mortality for OAR or EVAR, and EVAR conversion-to-open rate for all centers were calculated. The SVS guidelines for OAR and EVAR, individually and combined, were applied to each institution leading to a CMAG designation. The proportion of CMAGs by region (West, Midwest, South, and Northeast) were compared by year using a χ2 test. Temporal trends were estimated using a multivariable logistic regression for CMAG, adjusting by region. RESULTS: Overall, 67,865 patients (49,264 EVAR; 11,010 OAR; 7591 aortic bypasses) at 336 institutions were examined. The proportion of EVAR CMAGs increased nationally by 1.7% annually from 51.6% (n = 33/64) in 2011 to 67.1% (n = 190/283) in 2019 (ß = .05; 95% confidence interval [CI], 0.01-0.09; P = .02). The proportion of EVAR CMAGs across regions ranged from 27.3% to 66.7% in 2011 to 63.9% to 72.9% in 2019. In contrast, the proportion of OAR CMAGs has decreased nationally by 1.8% annually from 32.8% (n = 21/64) in 2011 to 16.3% (n = 46/283) in 2019 (ß = -.14; 95% CI, -0.19 to -0.10; P < .01). Combined EVAR and OAR CMAGs were even less frequent and decreased by 1.5% annually from 26.6% (n = 17/64) in 2011 to 13.1% (n = 37/283) in 2019 (ß = -.12; 95% CI, -0.17 to -0.07; P < .01). In 2019, there was no significant difference in regional variation of the proportion of combined EVAR and OAR CMAGs (P = .82). CONCLUSIONS: Although an increasing proportion of institutions nationally meet the SVS guidelines for EVAR, a smaller proportion meet them for OAR, with a concerning downward trend. These data question whether we can safely offer OAR at most institutions, have important implications about sufficient OAR exposure for trainees, and support regionalization of OAR.

Risk factors and associated outcomes of postoperative delirium after open abdominal aortic aneurysm repair.

OBJECTIVE: Open abdominal aortic aneurysm repair (OAR) is a major vascular procedure that incurs a large physiologic demand, increasing the risk for complications such as postoperative delirium (POD). We sought to characterize POD incidence, identify delirium risk factors, and evaluate the effect of delirium on postoperative outcomes. We hypothesized that POD following OAR would be associated with increased postoperative complications and resource utilization. METHODS: This was a retrospective study of all OAR cases from 2012 to 2020 at a single tertiary care center. POD was identified via a validated chart review method based on key words and Confusion Assessment Method assessments. The primary outcome was POD, and secondary outcomes included length of stay, non-home discharge, 90-day mortality, and 1-year survival. Bivariate analysis as appropriate to the data was used to assess the association of delirium with postoperative outcomes. Multivariable binary logistic regression was used to identify risk factors for POD and Cox regression for variables associated with worse 1-year survival. RESULTS: Overall, 198 OAR cases were included, and POD developed in 34% (n = 67). Factors associated with POD included older age (74 vs 69 years; P < .01), frailty (50% vs 28%; P < .01), preoperative dementia (100% vs 32%; P < .01), symptomatic presentation (47% vs 27%; P < .01), preoperative coronary artery disease (44% vs 28%; P = .02), end-stage renal disease (89% vs 32%; P < .01) and Charlson Comorbidity Index score >4 (42% vs 26%; P = .01). POD was associated with 90-day mortality (19% vs 5%; P < .01), non-home discharge (61% vs 30%; P < .01), longer median hospital length of stay (14 vs 8 days; P < .01), longer median intensive care unit length of stay (6 vs 3 days; P < .01), postoperative myocardial infarction (7% vs 2%; P = .045), and postoperative pneumonia (19% vs 8%; P = .01). On multivariable analysis, risk factors for POD included older age, history of end-stage renal disease, lack of epidural, frailty, and symptomatic presentation. A Cox proportional hazards model revealed that POD was associated with worse survival at 1 year (hazard ratio, 3.8; 95% confidence interval, 1.6-9.0; P = .003). CONCLUSIONS: POD is associated with worse postoperative outcomes and increased resource utilization. Future studies should examine the role of improved screening, implementation of delirium prevention bundles, and multidisciplinary care for the most vulnerable patients undergoing OAR.

Predictors of amputation-free survival and wound healing after infrainguinal bypass with alternative conduits.

OBJECTIVE: Inadequate vein quality or prior harvest precludes use of autologous single segment greater saphenous vein (ssGSV) in many patients with chronic limb-threatening ischemia (CLTI). Predictors of patient outcome after infrainguinal bypass with alternative (non-ssGSV) conduits are not well-understood. We explored whether limb presentation, bypass target, and conduit type were associated with amputation-free survival (AFS) after infrainguinal bypass using alternative conduits. METHODS: A single-center retrospective study (2013-2020) was conducted of 139 infrainguinal bypasses performed for CLTI with cryopreserved ssGSV (cryovein) (n = 71), polytetrafluoroethylene (PTFE) (n = 23), or arm/spliced vein grafts (n = 45). Characteristics, Wound, Ischemia, and foot Infection (WIfI) stage, and outcomes were recorded. Multivariable Cox proportional hazards and classification and regression tree analysis modeled predictors of AFS. RESULTS: Within 139 cases, the mean age was 71 years, 59% of patients were male, and 51% of cases were nonelective. More patients undergoing bypass with cryovein were WIfI stage 4 (41%) compared with PTFE (13%) or arm/spliced vein (27%) (P = .04). Across groups, AFS at 2 years was 78% for spliced/arm, 79% for PTFE, and 53% for cryovein (adjusted hazard ratio for cryovein, 2.5; P = .02). Among cases using cryovein, classification and regression tree analysis showed that WIfI stage 3 or 4, age >70 years, and prior failed bypass were predictive of the lowest AFS at 2 years of 36% vs AFS of 58% to 76% among subgroups with less than two of these factors. Although secondary patency at 2 years was worse in the cryovein group (26% vs 68% and 89% in arm/spliced and PTFE groups; P < .01), in patients with tissue loss there was no statistically significant difference in wound healing in the cryovein group (72%) compared with other bypass types (72% vs 87%, respectively; P = .12). CONCLUSIONS: In patients with CLTI lacking suitable ssGSV, bypass with autogenous arm/spliced vein or PTFE has superior AFS compared with cryovein, although data were limited for PTFE conduits for distal targets. Despite poor patency with cryovein, wound healing is achieved in a majority of cases, although it should be used with caution in older patients with high WIfI stage and prior failed bypass, given the low rates of AFS.

Development and Validation of a Novel Preoperative Risk Score to Identify Patients at Risk for Nonhome Discharge after Elective Endovascular Aortic Aneurysm Repair (EVAR).

BACKGROUND: Nonhome discharge (NHD) to a rehabilitation or skilled nursing facility after elective endovascular aortic repair (EVAR) is uncommon. However, NHD after surgery has an important impact on patient quality of life and postdischarge outcomes. Understanding factors that put patients undergoing EVAR at high risk for NHD is essential to providing adequate preoperative counseling and shared decision making. This study aimed to identify independent predictors of NHD following elective EVAR and to create a clinically useful preoperative risk score. METHODS: Elective EVAR cases were queried from the Society for Vascular Surgery Vascular Quality Initiative 2014-2018. A risk score was created by splitting the data set into two-thirds for development and one-third for validation. A parsimonious stepwise hierarchical multivariable logistic regression controlling for hospital level variation was performed in the development dataset, and the beta-coefficients were used to assign points for a risk score. The score was then validated, and model performance assessed. RESULTS: Overall, 24,426 patients were included and 932 (3.8%) required NHD. Multivariable analysis in the development group identified independent predictors of NHD, which were used to create a 20-point risk score. Patients were stratified into 3 groups based upon their risk score: low risk (0-7 points; n = 16,699) with an NHD rate of 1.8%, moderate risk (8-13 points; n = 7,315) with an NHD rate of 7.3%, and high risk (≥14 points; n = 412) with an NHD rate of 21.8%. The risk score had good predictive ability with c-statistic = 0.75 for model development and c-statistic = 0.73 in the validation dataset. CONCLUSIONS: This novel risk score can predict NHD following EVAR using characteristics that can be identified preoperatively. Utilization of this score may allow for improved risk assessment, preoperative counseling, and shared decision making.

Readability of Spanish-Language Online Patient Educational Materials for Peripheral Artery Disease Do Not Meet Recommended Standards and Represent a Literacy Barrier to Care.

BACKGROUND: Online resources are a valuable source of information for patients and have been reported to improve engagement and adherence to medical care. However, readability of online patient educational materials (OPEMs) is crucial for them to serve their intended purpose. The American Medical Association (AMA) recommends that OPEM be written at or below the sixth grade reading level. To avoid disparities in access to comprehensible health information on peripheral artery disease (PAD), it is imperative that the readability of PAD OPEM is appropriate for both English-speaking and Spanish-speaking patients. The aim of this study is to evaluate the readability of PAD OPEM in Spanish and compare to English-language OPEM. METHODS: We conducted a Google search in English and Spanish using "peripheral arterial disease" and "enfermedad arterial periferica", respectively, and the top 25 patient-accessible articles were collected for each. Articles were categorized by source type: hospital, professional society, or other. Readability of English-language OPEM was measured using the Flesch Reading Ease Readability Formula, Automated Readability Index, Coleman-Liau Index, Flesch-Kincaid Grade Level, Gunning Fog, Linsear Write Formula, and the Simple Measure of Gobbledygook Index. Readability of Spanish OPEM was measured using the Fernández-Huerta Index and Índice Flesch-Szigriszt Scale. Readability of the articles was compared to the AMA recommendation, between English- and Spanish-language, and across sources using statistical tests appropriate to the data. RESULTS: OPEM from professional societies represented the fewest number of English- (n = 7, 28%) and Spanish-language (n = 6, 24%) articles. Most English-speaking (n = 18, 72%) and Spanish-language (n = 20, 80%) OPEM were considered difficult as measured by the Flesch Reading Ease Readability Formula and Fernández-Huerta Index, respectively, but did not significantly differ between languages (P = 0.59). There were no significant differences in the average readability of all readability measurements across sources (hospital, professional society, or other). All the average readability grade levels for English-speaking and Spanish-language OPEM was significantly higher than the sixth grade reading level (P < 0.01). Only 3 (6%) OPEM met the AMA recommended reading level and there was no significant difference between English-language and Spanish-language OPEM (P = 1.0). CONCLUSIONS: Nearly all Spanish-language and English-language PAD OPEM assessed were written at a reading grade level higher than recommended by the AMA. There was no significant difference in the readability of materials from hospitals or professional societies. To prevent further widening of health disparities related to literacy, health content creators, particularly hospitals and professional societies, should prioritize, develop, and ensure that English-language and Spanish-language patient education materials are written at a level appropriate for the public.

Anemia is associated with higher mortality and morbidity after thoracic endovascular aortic repair.

BACKGROUND: It is uncertain whether preoperative anemia is independently associated with thoracic endovascular aortic repair (TEVAR) outcomes. Using a national vascular surgery database, we evaluated the associations between preoperative anemia and 30-day mortality, postoperative complications, and 1-year survival for patients undergoing TEVAR. METHODS: We retrospectively analyzed all patients in the Vascular Quality Initiative who had undergone TEVAR for aortic dissection, aortic aneurysm, penetrating aortic ulcer, hematoma, or thrombus between January 2011 and December 2019. We excluded patients with a ruptured aneurysm, traumatic dissection, emergent repair, treated aorta distal to zone 5, polycythemia, transfusion of >4 U of packed red blood cells intraoperatively or postoperatively, and missing data on hemoglobin level or surgical indications. The final study cohort was dichotomized into two groups: normal/mild anemia (women, ≥10 g/dL; men, ≥12 g/dL) and moderate/severe anemia (women, <10 g/dL; male, <12 g/dL). Propensity scores by stratification were used to control for confounding in the analysis of the association between the outcomes of 30-day mortality, postoperative complications, and 1-year survival and a binary indicator variable of moderate/severe anemia vs normal/mild anemia. Kaplan-Meier analysis and log-rank tests were used to compare the 1-year survival between the two groups. A Cox regression model was fitted to assess the associations between anemia and survival outcomes. RESULTS: A total of 3391 patients were analyzed, 958 (28.3%) of whom had had moderate/severe anemia. After adjustment for multiple clinical factors using propensity score stratification, moderate/severe anemia was associated with a 141% increased odds of 30-day mortality (adjusted odds ratio [aOR], 2.41; 95% confidence interval [CI], 1.15-5.05; P = .019), 58% increased odds of any in-hospital complication (aOR, 1.58; 95% CI, 1.17-2.13; P = .003), 281% increased odds of intraoperative transfusion (aOR, 3.81; 95% CI, 2.68-5.53; P < .001). In addition, moderate/severe anemia was associated with significantly worse survival within the first year after TEVAR (log-rank P < .001; 1-year survival rate using Kaplan-Meier estimates, 86.4% ± 1.3% standard error vs 92.5% ± 0.6% standard error) and with an increased risk of mortality in the first postoperative year (adjusted hazard ratio, 1.81; 95% CI, 1.16-2.82; P = .009). CONCLUSIONS: We found that moderate or severe anemia is associated with significantly increased odds of mortality, postoperative complications, and worse 1-year survival after TEVAR. Future studies are needed to evaluate the effect of anemia correction on the outcomes of TEVAR.

Structured discharge documentation reduces sex-based disparities in statin prescription in vascular surgery patients.

OBJECTIVE: Perioperative statin use has been shown to improve survival in vascular surgery patients. In 2018, the Northern California Vascular Study Group implemented a quality initiative focused on the use of a SmartText in the discharge summary. We hypothesized that structured discharge documentation would decrease sex-based disparities in evidence-based medical therapy. METHODS: A retrospective analysis was conducted using Vascular Quality Initiative eligible cases at a single institution. Open or endovascular procedures in the abdominal aorta or lower extremity arteries from 2016 to 2021 were included. Bivariate analysis identified factors associated with statin use and sex. Multivariate logistic regression was performed with the end point of statin prescription at discharge and aspirin prescription at discharge. An interaction term assessed the differential impact of the initiative on both sexes. Analysis was then stratified by prior aspirin or statin prescription. An interrupted time series analysis was used to evaluate the trend in statin prescription over time. RESULTS: Overall, 866 patients were included, including 292 (34%) female and 574 (66%) male patients. Before implementation, statins were prescribed in 77% of male and 62% of female patients (P < .01). After implementation, there was no statistically significant difference in statin prescription (91% in male vs 92% in female patients, P = .68). Female patients saw a larger improvement in the adjusted odds of statin prescription compared with male patients (odds ratio: 3.1, 95% confidence interval: 1.1-8.6, P = .04). For patients not prescribed a statin preoperatively, female patients again saw an even larger improvement in the odds of being prescribed a statin at discharge (odds ratio: 6.4, 95% confidence interval: 1.8-22.7, P < .01). Interrupted time series analysis demonstrated a sustained improvement in the frequency of prescription for both sexes over time. The unadjusted frequency of aspirin prescription also improved by 3.5% in male patients vs 5.5% in female patients. For patients not prescribed an aspirin preoperatively, we found that the frequency of aspirin prescription significantly improved for both male (19% increase, P = .006) and female (31% increase, P = .001) patients. There was no significant difference in the perioperative outcomes between male and female patients before and after standardized discharge documentation. CONCLUSIONS: A simple, low-cost regional quality improvement initiative eliminated sex-based disparities in statin prescription at a single institution. These findings highlight the meaningful impact of regional quality improvement projects. Future studies should examine the potential for structured discharge documentation to improve patient outcomes and reduce disparities.

Open revascularization approach is associated with healing and ambulation after transmetatarsal amputation in patients with chronic limb threatening ischemia.

BACKGROUND: Transmetatarsal amputation (TMA) allows for maintenance of ambulatory function for patients with significant forefoot tissue loss. Effective revascularization is key to optimizing limb salvage for patients with chronic limb threatening ischemia (CLTI). We hypothesized that CLTI patients requiring TMA will have better healing and functional outcomes with open bypass than with endovascular revascularization. METHODS: Consecutive TMAs performed at three affiliated centers between 2008 and 2020 were retrospectively reviewed. The baseline characteristics, including WIfI (wound, ischemia, foot infection) stage, noninvasive vascular studies, healing, and ambulatory outcomes, were collected. Catheter-based angiographic images were evaluated using the GLASS (global limb anatomic staging system). The primary outcomes were TMA healing and community ambulation. The secondary outcomes were TMA that had healed at study end, any ambulatory function postoperatively, major amputation, and mortality. Descriptive statistics and univariate, multivariable, and Kaplan-Meier analyses were performed. RESULTS: A total of 346 TMAs had been performed in 318 patients, 209 of whom had had peripheral artery disease (PAD). The median follow-up was 2.5 years. Patients with PAD had had significantly lower rates of healing compared with those without PAD (64% vs 77%; P = .007). Revascularization was performed in 185 limbs, with 102 treated endovascularly and 83 with open surgery. The patients who had undergone endovascular surgery were significantly less likely to have had the TMA healed at any point (55% vs 76%; P = .003) and less likely to have remained healed at study end (49% vs 66%; P = .02). Patients with GLASS stage 3 anatomy were significantly more likely to have healed after open surgery (75% vs 45%; P = .003). Long-term ambulation data were available for 72% of the revascularized patients. Endovascular surgery was associated with a lower likelihood of community ambulation after TMA (34% vs 57%; P = .002). On multivariable analysis, open surgery was significantly associated with TMA healing (odds ratio, 2.8; P = .007) and ambulation (odds ratio, 2.9; P = .001). CONCLUSIONS: For patients with CLTI and significant tissue loss requiring TMA, an initial open approach to revascularization was associated with improved healing and higher rates of ambulation compared with endovascular interventions. The metabolic requirement for healing of a TMA in patients with CLTI might be better met by open revascularization.

Racial and ethnic disparities in major adverse limb events persist for chronic limb threatening ischemia despite presenting limb threat severity after peripheral vascular intervention.

OBJECTIVE: Racial and ethnic disparities have been well-documented in the outcomes for chronic limb threatening ischemia (CLTI). One purported explanation has been the disease severity at presentation. We hypothesized that the disparities in major adverse limb events (MALE) after peripheral vascular intervention (PVI) for CLTI would persist despite controlling for disease severity at presentation using the WIfI (Wound, Ischemia, foot Infection) stage. METHODS: The Vascular Quality Initiative PVI dataset (2016-2021) was queried for CLTI. Patients were excluded if they were missing the WIfI stage. The primary end point was the incidence of 1-year MALE, defined as major amputation (through the tibia or fibula or more proximally) or reintervention (endovascular or surgical) of the initial treatment limb. A multivariate hierarchical Fine-Gray analysis was performed, controlling for hospital variation, competing risk of death, and presenting WIfI stage, to assess the independent association of Black/African American race and Latinx/Hispanic ethnicity with MALE. A Cox proportional hazard regression model was used for the 1-year survival analysis. RESULTS: Overall, 47,830 patients (60%) had had WIfI scores reported (73% White, 20% Black, and 7% Latinx). The 1-year unadjusted cumulative incidence of MALE was 13.1% (95% confidence interval [CI], 12.6%-13.5%) for White, 14.3% (95% CI, 13.5%-15.3%) for Black, and 17.0% (95% CI, 15.3%-18.9%) for Latinx patients. On bivariate analysis, the occurrence of MALE was significantly associated with younger age, Black race, Latinx ethnicity, coronary artery disease, cerebrovascular disease, congestive heart failure, hypertension, diabetes, dialysis, intervention level, any prior minor or major amputation, and WIfI stage (P < .001). The cumulative incidence of 1-year MALE increased by increasing WIfI stage: stage 1, 11.7% (95% CI, 10.9%-12.4%); stage 2, 12.4% (95% CI, 11.8%-13.0%); stage 3, 14.8% (95% CI, 13.8%-15.8%); and stage 4, 15.4% (95% CI, 14.3%-16.6%). The cumulative incidence also increased by intervention level: inflow, 10.7% (95% CI, 9.8%-11.7%), femoropopliteal, 12.3% (95% CI, 11.7%-12.9%); and infrapopliteal, 14.1% (95% CI, 13.5%-14.8%). After adjustment for WIfI stage only, Black race (subdistribution hazard ratio [SHR], 1.30; 95% CI, 1.17-1.44; P < .001) and Latinx ethnicity (SHR, 1.58; 95% CI, 1.37-1.81; P < .001) were associated with an increased 1-year hazard of MALE compared with White race. On adjusted multivariable analysis, MALE disparities persisted for Black/African American race (SHR, 1.12; 95% CI, 1.01-1.25; P = .028) and Latinx/Hispanic ethnicity (SHR, 1.34; 95% CI, 1.16-1.54; P < .001) compared with White race. CONCLUSIONS: Black/African American and Latinx/Hispanic patients had a higher associated hazard of MALE after PVI for CLTI compared with White patients despite an adjustment for WIfI stage at presentation. These results suggest that disease severity at presentation does not account for disparities in outcomes. Further work should focus on better understanding the underlying mechanisms for disparities in historically marginalized racial and ethnic groups presenting with CLTI.

Low-volume surgeons can have better outcomes at certain hospital settings for open abdominal aortic repairs.

OBJECTIVE: The volume-outcomes relationship is cross-cutting among open abdominal aortic operations, where higher-volume surgeons have better perioperative outcomes. However, there has been minimal focus on low-volume surgeons and how to improve their outcomes. This study sought to identify if there are any differences in outcomes among low-volume surgeons for open abdominal aortic surgeries by different hospital settings. METHODS: We used the 2012-2019 Vascular Quality Initiative registry to identify all patients who underwent open abdominal aortic surgery for aneurysmal or aorto-iliac occlusive disease by a low-volume surgeon (<7 operations annually). We categorized high-volume hospitals using three distinct definitions: those that performed ≥10 operations annually, those with at least one high-volume surgeon, and by the number of surgeons (1-2 surgeons, 3-4 surgeons, 5-7 surgeons, and 8+ surgeons). Outcomes included 30-day perioperative mortality, overall complications, and failure-to-rescue. We compared outcomes among low-volume surgeons using univariable and multivariable logistic regressions across each of these three hospital categorizations. RESULTS: Among 14,110 patients who underwent open abdominal aortic surgery, 10,252 (7 3%) were performed by 1155 low-volume surgeons. Two-thirds of these patients (66%) underwent their surgery at a high-volume hospital, fewer than one-third (30%) at a hospital that had at least one high-volume surgeon, and one-half (49%) at hospitals with at least five surgeons. Among all patients operated on by low-volume surgeons, rates of 30-day mortality were 3.8%, perioperative complications were 35.3%, and failure-to-rescue were 9.9%. Low-volume surgeons operating at high-volume hospitals for aneurysmal disease had lower rates of perioperative death (adjusted odds ratio [aOR], 0.66; 95% confidence interval [CI], 0.48-0.90) and failure-to-rescue (aOR, 0.70; 95% CI, 0.50-0.98), but similar rates of complications (aOR, 1.06; 95% CI, 0.89-1.27). Similarly, patients undergoing their operation at hospitals that had at least one high-volume surgeon had lower rates of death (aOR, 0.71; 95% CI, 0.50-0.99) for aneurysmal disease. Patient outcomes among low-volume surgeons for aorto-iliac occlusive disease did not vary by hospital setting. CONCLUSIONS: The majority of patients undergoing open abdominal aortic surgery have a low-volume surgeon, where outcomes are slightly better for those taking place at a high-volume hospital. Focused and incentivized interventions may be needed to improve outcomes among low-volume surgeons across all practice settings.

Dynamic Contrast-Enhanced MRI in Abdominal Aortic Aneurysms as a Potential Marker for Disease Progression.

BACKGROUND: Abdominal aortic aneurysms (AAAs) may rupture before reaching maximum diameter (Dmax ) thresholds for repair. Aortic wall microvasculature has been associated with elastin content and rupture sites in specimens, but its relation to progression is unknown. PURPOSE: To investigate whether dynamic contrast-enhanced (DCE) MRI of AAA is associated with Dmax or growth. STUDY TYPE: Prospective. POPULATION: A total of 27 male patients with infrarenal AAA (mean age ± standard deviation = 75 ± 5 years) under surveillance with DCE MRI and 2 years of prior follow-up intervals with computed tomography (CT) or MRI. FIELD STRENGTH/SEQUENCE: A 3-T, dynamic three-dimensional (3D) fast gradient-echo stack-of-stars volumetric interpolated breath-hold examination (Star-VIBE). ASSESSMENT: Wall voxels were manually segmented in two consecutive slices at the level of Dmax . We measured slope to 1-minute and area under the curve (AUC) to 1 minute and 4 minutes of the signal intensity change postcontrast relative to that precontrast arrival, and, Ktrans , a measure of microvascular permeability, using the Patlak model. These were averaged over all wall voxels for association to Dmax and growth rate, and, over left/right and anterior/posterior quadrants for testing circumferential homogeneity. Dmax was measured orthogonal to the aortic centerline and growth rate was calculated by linear fit of Dmax measurements. STATISTICAL TESTS: Pearson correlation and linear mixed effects models. A P value <0.05 was considered statistically significant. RESULTS: In 44 DCE MRIs, mean Dmax was 45 ± 7 mm and growth rate in 1.5 ± 0.4 years of prior follow-up was 1.7 ± 1.2 mm per year. DCE measurements correlated with each other (Pearson r = 0.39-0.99) and significantly differed between anterior/posterior versus left/right quadrants. DCE measurements were not significantly associated with Dmax (P = 0.084, 0.289, 0.054 and 0.255 for slope, AUC at 1 minute and 4 minutes, and Ktrans , respectively). Slope and 4 minutes AUC significantly associated with growth rate after controlling for Dmax . CONCLUSION: Contrast uptake may be increased in lateral aspects of the AAA. Contrast enhancement 1-minute slope and 4-minutes AUC may be associated with a period of recent AAA growth that is independent of Dmax . EVIDENCE LEVEL: 3. TECHNICAL EFFICACY: Stage 2.

Guideline Compliant Minimum Asymptomatic Carotid Endarterectomy Surgeon and Hospital Volume Cutoffs.

BACKGROUND: There is a known association between volume and outcomes after carotid endarterectomy (CEA). A recent analysis suggested rates of stroke and death do not significantly reduce after a surgeon volume cutoff of 20 CEAs per year. However, these results would severely limit access. The objective here is to identify a lower optimal cutpoint for surgeon and hospital volume for asymptomatic CEA. METHODS: We evaluated asymptomatic CEA patients using The New York Statewide Planning and Research Cooperative System database from 2000-2014. The relationship of 3-year averaged volumes for surgeons and hospitals to 30-day stroke was assessed using multiple logistic regression and included both hospital and surgeon volume in all analyses. Optimized cut points were the lowest significant volume cutoff that minimized the adjusted odds ratio of stroke. RESULTS: We studied 32,549 CEAs performed by 271 surgeons in 136 centers by vascular surgeons. The median surgeon volume was 26.3 (interquartile range: 12.3-51.7) and the median hospital volume was 67 (interquartile range: 36.3-119.3). The surgeon volume cut point was 3 and the hospital volume cut point was 6 cases per year. There were 756 (2.3%) procedures performed by surgeons with a volume < 3 and 560 (1.7%) procedures performed by hospitals with a volume < 6. Perioperative stroke and death rates were 2.0% (95% confidence interval [CI]: 1.8-2.1) and 3.8% (95% CI: 2.6-5.5) for an average yearly surgeon volume ≥ 3 and < 3 (P = 0.070), respectively. The combined stroke and death rate was 2.0% (95% CI: 1.8-2.1) and 4.8% (95% CI: 3.2-7.0) for an average yearly center volume ≥ 6 and < 6 (P = 0.007), respectively. A combined surgeon and hospital volume variable also predicted outcomes and low-volume procedures did not meet previously proposed American Heart Association and Society for Vascular Surgery quality measures. CONCLUSIONS: These data demonstrate an improvement in outcomes at a lower volume threshold than previously reported. These modest cutoff values should be used for asymptomatic CEA volume guideline formation and for future studies, after accounting for the impact of other important factors that may be driving volume-outcome relationships in asymptomatic CEA.

High-Risk Characteristics for Clinical Failure after Isolated Femoropopliteal Peripheral Vascular Interventions.

BACKGROUND: Recent studies suggesting increased late mortality with paclitaxel-coated devices (PCDs) in femoropopliteal peripheral vascular interventions (PVIs) prompted the US Food and Drug Administration to recommend limiting the use of PCDs to "patients at particularly high risk for restenosis". This study's aim is to characterize patients at high risk for restenosis and develop a risk score to guide clinicians in selecting patients for treatment with PCDs. METHODS: Patients who underwent isolated femoropopliteal PVI for claudication or rest pain from 2016-2019 in the Vascular Quality Initiative were included. Patients who received intervention with a PCD, hybrid procedures, died within 1 year, or had missing follow-up data were excluded. The primary end point was clinical failure at 1 year defined as > 50% restenosis, loss of patency, reintervention, or major amputation. Data were split randomly into 2/3 for development and 1/3 for validation. A parsimonious multivariable hierarchical logistic regression for clinical failure was developed and a risk score was created using beta-coefficients. The risk score was applied to the validation dataset and tested for goodness-of-fit and discrimination. RESULTS: Among 4,856 treated patients, 718 (14.8%) experienced clinical failure within 1 year. Clinical failure was associated with age ≤ 50 years, female sex (48.1% vs. 39.5%), insulin-dependent diabetes (29.9% vs. 23.1%), creatinine > 2.0 mg/dL (9.9% vs. 5.7%), prior ipsilateral lower extremity revascularization (48.5% vs. 38.5%), prior ipsilateral minor amputation (5.3% vs. 1.7%), rest pain versus claudication (30.8% vs. 18.7%), occlusion length ≥ 20 cm (18.8% vs. 15.0%), and Trans-Atlantic Inter-Society Consensus II Classification C or D (40.4% vs. 28.0%), all P ≤ 0.01. Risk score development was performed using a multivariable regression. The model demonstrated good fit and discrimination (C-statistic 0.71 in development and 0.72 in validation dataset). Predicted clinical failure was 8.9% for standard-risk (45.9% of interventions), 15.5% for high-risk (44.2% of interventions), and 33.8% for very high-risk patients (9.8% of interventions). CONCLUSIONS: A novel risk score was created with good discrimination for identifying patients at high risk for clinical failure at 1 year after femoropopliteal PVI for claudication and rest pain. Patients at high risk and very high risk for clinical failure may benefit from alternative strategies including PCDs.

Cognitive Impairment is Common in a Veterans Affairs Population with Peripheral Arterial Disease.

BACKGROUND: Despite the shared pathogenesis of peripheral arterial disease (PAD) and vascular dementia, there are little data on cognitive impairment in PAD patients. We hypothesized that cognitive impairment will be common and previously unrecognized. METHODS: Cognitive impairment screening was prospectively performed for veterans presenting to a single Veterans Affairs outpatient vascular surgery clinic from 2020-2021 for PAD consultation or disease surveillance. Overall, 125 Veterans were screened. Cognitive impairment was defined as a score of <26 on the Montreal Cognitive Assessment (MoCA) survey. A multivariable logistic regression assessed for independent risk factors for cognitive impairment. RESULTS: Overall, 77 (61%) had cognitive impairment, 92% was previously unrecognized. Cognitive impairment was associated with increased age (74.4 vs. 71.8 years, P = 0.03), Black versus White race (94% vs. 54%, P < 0.01), hypertension (66% vs. 31%, P = 0.01), prior stroke/TIA (79% vs. 58%, P = 0.03), diabetes treated with insulin (79% vs. 58%, P = 0.05), and post-traumatic stress disorder (PTSD) (80% vs. 57%, P = 0.04). On multivariable analysis, risk factors for newly diagnosed cognitive impairment included age ≥70 years, diabetes treated with insulin, PTSD, and Black race. CONCLUSIONS: Many veterans with PAD have evidence of cognitive impairment and is overwhelmingly underdiagnosed. This study suggests cognitive impairment is an unrecognized issue in a VA population with PAD, requiring more study to determine cognitive impairment's impact on surgical outcomes, and how it can be mitigated and incorporated into clinical care.

Association of Intraoperative and Perioperative Transfusions with Postoperative Cardiovascular Events and Mortality After Infrainguinal Revascularization.

BACKGROUND: Patients undergoing open or endovascular infrainguinal revascularization are at an elevated risk for postoperative cardiovascular complications due to high rates of comorbidities and the physiologic stress of surgery. Transfusions are known to be associated with adverse events but knowledge of specific risks associated with transfusion timing, product type, and long-term outcomes while accounting for preoperative cardiovascular risk factors is not well understood in this population. This study aimed to characterize the association of intraoperative and perioperative transfusion, anemia, and cardiovascular risk factors with cardiovascular events and mortality in patients undergoing infrainguinal revascularization. METHODS: A single-center retrospective study was performed on 564 infrainguinal revascularization procedures, including both open (n = 250) and endovascular (n = 314) approaches (2016-2020). Comprehensive clinical data were collected including patient demographics, cardiovascular risk factors, preoperative hemoglobin, and detailed transfusion data. Multivariable logistic regression tested the association of transfusions with composite 30-day outcomes of cardiac complications (postoperative myocardial infarction [postop-MI], congestive heart failure, or dysrhythmia) and with major adverse cardiovascular events (MACE-postop-MI or death). Kaplan-Meier analysis and Cox proportional hazard modeling examined the association of transfusions, anemia, and cardiovascular risk factors with mortality up to 1 year. RESULTS: Intraoperative transfusion was performed in 15% of cases and 13% underwent transfusion in the early postoperative period. Intraoperative transfusion was associated with higher Revised Cardiac Risk Index (RCRI), lower preoperative hemoglobin, increased blood loss, and open procedures (all P < 0.05). Within each RCRI score, intraoperative transfusion was associated with 2-4-fold increased MACE at 30 days. Intraoperative packed red blood cells transfusion and early postoperative packed red blood cells transfusion was associated with more than 2-fold adjusted odds of any cardiovascular complication and intraoperative transfusion was also associated with MACE (all P < 0.05). Intraoperative transfusion was associated with mortality at 1 year on unadjusted analysis, but after adjustment for RCRI, age, and preoperative hemoglobin, only RCRI scores of 2 and 3+ and preoperatively hemoglobin remained significant risk factors for mortality. CONCLUSIONS: Intraoperative and early perioperative transfusions are strongly associated with worse cardiovascular outcomes after infrainguinal revascularization. These findings may have a prognostic value for further risk stratifying patients perioperatively at a high risk for complications. However, prospective studies are needed to elucidate whether optimizing transfusion strategies mitigates these risks.

Capturing the complexity of open abdominal aortic surgery in the endovascular era.

OBJECTIVE: Volume and quality benchmarks for open abdominal aortic surgery and particularly open aortic aneurysm repair (OAR) in the endovascular era are guided by the Society for Vascular Surgery guidelines, but the Vascular Quality Initiative (VQI) OAR module fails to capture the full spectrum of complex OAR. We hypothesized that VQI-ineligible complex OAR would be the dominant form of open repairs performed at a VQI-participating tertiary center. METHODS: All OAR cases performed at a single tertiary care center from 2007 to 2020 were reviewed. The VQI OAR criteria were applied with exclusions (non-VQI) defined as concomitant renal bypass, clamping above the superior mesenteric artery or celiac artery, repairs performed for trauma, anastomotic aneurysm, isolated iliac aneurysm, or infected aneurysms. Linear regression was used to assess temporal trends. RESULTS: Among a total of 481 open abdominal aortic operations, 355 (74%) were OAR. The average annual OAR volume remained stable over 14 years (25 ± 6; P = .46). Non-VQI OAR comprised 54% of all cases and persisted over time (R2 = 0.047, P = .46). Supraceliac clamping (35%) was often necessary. The proportion of endograft explantation cases significantly increased over time from 4% in 2007 to 20% in 2019 (P = .01). Infectious indications represented 20% (n = 70) of cases. Visceral branch grafts were performed in 16% of all cases. OAR for ruptured aneurysm constituted 10% of cases. Thirty-day mortality was significantly higher in non-VQI vs VQI-eligible OAR cases (10% vs 4%; P = .04). CONCLUSIONS: Complex OAR comprises a majority of OAR cases in a contemporary tertiary referral hospital, yet these cases are not accounted for in the VQI. Creation of a "complex OAR" VQI module would capture these cases in a quality-driven national registry and help to better inform benchmarks for volume and outcomes in aortic surgery.

Clinical Predictors and Outcomes Associated with Postoperative Delirium Following Infrainguinal Bypass Surgery.

BACKGROUND: Post-operative delirium (POD) is common yet often underdiagnosed following vascular surgery. Elderly patients with advanced peripheral artery disease may be at particular risk for POD yet understanding of the clinical predictors and impact of POD is incomplete. We sought to identify POD predictors and associated resource utilization after infrainguinal lower extremity bypass. METHODS: This single center retrospective analysis included all infrainguinal bypass cases performed for peripheral arterial disease from 2012-2020. The primary outcome was inpatient POD. Delirium sequelae were also evaluated. Key secondary outcomes were length of stay, nonhome discharge, readmission, 30-day amputation, post-operative myocardial infarction, mortality, and 2-year survival. Regression analysis was used to evaluate risk factors for delirium in addition to association with 2-year survival and amputation free survival. RESULTS: Among 420 subjects undergoing infrainguinal lower extremity bypass, 105 (25%) developed POD. Individuals with POD were older and more likely to have non-elective surgery (P < 0.05). On multivariable analysis, independent predictors of POD were age 60-89 years old, chronic limb threatening ischemia, female sex, and nonelective procedure. Consultations for POD took place for 25 cases (24%); 13 (52%) were with pharmacists, and only 4 (16%) resulted in recommendations. The average length of stay for those with POD was higher (17 days vs. 9 days; P < 0.001). POD was associated with increased non-home discharge (61.8% vs. 22.1%; P < 0.001), 30-day major amputation (6.7% vs. 1.6%; P < 0.01), 30-day postoperative myocardial infarction (11.4% vs. 4.1%; P < 0.01), and 90-day mortality (7.6% vs. 2.9%; P = 0.03). Survival at 2 years was lower in those with delirium (89% vs. 75%; P < 0.001). In a Cox proportional hazards model, delirium was independently associated with decreased survival (HR = 2.0; 95% CI = 1.15-3.38; P = 0.014) and decreased major-amputation free survival (HR = 1.9; 95% CI = 1.18-2.96; P = 0.007). CONCLUSIONS: POD is common following infrainguinal lower extremity bypass and is associated with other adverse post-operative outcomes and increased resource utilization, including increased hospital length of stay, nonhome discharge, and worse 2-year survival. Future studies should evaluate the role of routine multidisciplinary care for high-risk patients to improve perioperative outcomes for vulnerable older adults undergoing infrainguinal lower extremity bypass.

One-year patient survival correlates with surgeon volume after elective open abdominal aortic surgery.

OBJECTIVE: Volume-outcome relationships in surgery have been well established. Studies have shown that high-volume surgeons provide improved outcomes in performing open abdominal aneurysm repairs. The hypothesis of this study was that high-volume surgeons provide superior short-term and midterm outcomes of elective open aortic operations compared with low-volume surgeons. METHODS: We evaluated patients undergoing elective open abdominal aortic aneurysm repair, aortofemoral bypass, and aortomesenteric bypass by board-certified vascular surgeons using the New York Statewide Planning and Research Cooperative System database from 2002 to 2014. The Contal and O'Quigley technique was used to estimate a cut point objectively and provided an estimate of significance. A division using average yearly volumes (averaged during 3 years) of seven or more cases and fewer than seven cases per year returned the highest Q statistic, and this grouping was used to classify high-volume and low-volume provider groups. Rates of complications during index hospitalization, length of stay, 30-day survival, 90-day survival, 1-year survival, and cause of death were analyzed using mixed effect models. RESULTS: In 118 hospitals during the 13-year period, 266 board-certified vascular surgeons performed 244 aortomesenteric bypasses, 4202 aortofemoral bypasses, and 6126 abdominal aortic aneurysm repairs. High-volume surgeons' rates of complications during index hospitalization, 30-day survival, 90-day survival, and 1-year survival were superior to those of low-volume surgeons. The Contal and O'Quigley technique returned an estimate of seven operations per year for optimal survival during 1 year. This cutoff is associated with an adjusted 1-year hazard ratio of 0.687 (P = .003), a 2.69% difference in 1-year all-cause survival (P = .003), and a 1.76-day reduction in the mean length of stay at index hospitalization (P < .001). Higher volume surgeons showed a 25.0%, 43.4%, 42.4%, 40.6%, and 45.0% reduction in postoperative rates of acute renal failure (P < .001), hemorrhage (P < .001), pulmonary failure (P < .001), sepsis (P < .001), and venous thromboembolism (P < .001), respectively. Abdominal abscess, acute renal failure, hemorrhage, myocardial infarction, and sepsis were associated with increased cardiovascular cause-specific mortality after open aortic operations (P < .001). CONCLUSIONS: These data demonstrate that high-volume surgeons performing elective open aortic operations provide reduced complications and improved short-term and midterm survival compared with low-volume surgeons. Clinical and postoperative variables that are associated with increased cardiovascular cause-specific mortality are also identified. These data provide further evidence that elective open abdominal vascular surgery should be centralized to high-volume surgeons.

Understanding value and patient complexity among common inpatient vascular surgery procedures.

OBJECTIVE: Vascular surgery patients are highly complex, second only to patients undergoing cardiac procedures. However, unlike cardiac surgery, work relative value units (wRVU) for vascular surgery were undervalued based on an overall patient complexity score. This study assesses the correlation of patient complexity with wRVUs for the most commonly performed inpatient vascular surgery procedures. METHODS: The 2014 to 2017 National Surgical Quality Improvement Program Participant Use Data Files were queried for inpatient cases performed by vascular surgeons. A previously developed patient complexity score using perioperative domains was calculated based on patient age, American Society of Anesthesiologists class of ≥4, major comorbidities, emergent status, concurrent procedures, additional procedures, hospital length of stay, nonhome discharge, and 30-day major complications, readmissions, and mortality. Procedures were assigned points based on their relative rank and then an overall score was created by summing the total points. An observed to expected ratio (O/E) was calculated using open ruptured abdominal aortic aneurysm repair (rOAAA) as the referent and then applied to an adjusted median wRVU per operative minute. RESULTS: Among 164,370 cases, patient complexity was greatest for rOAAA (complexity score = 128) and the least for carotid endarterectomy (CEA) (complexity score = 29). Patients undergoing rOAAA repair had the greatest proportion of American Society of Anesthesiologists class of ≥IV (84.8%; 95% confidence interval [CI], 82.6%-86.8%), highest mortality (35.5%; 95% CI, 32.8%-38.3%), and major complication rate (87.1%; 95% CI, 85.1%-89.0%). Patients undergoing CEA had the lowest mortality (0.7%; 95% CI, 0.7%-0.8%), major complication rate (8.2%; 95% 95% CI, 8.0%-8.5%), and shortest length of stay (2.7 days; 95% CI, 2.7-2.7). The median wRVU ranged from 10.0 to 42.1 and only weakly correlated with overall complexity (Spearman's ρ = 0.11; P < .01). The median wRVU per operative minute was greatest for thoracic endovascular aortic repair (0.25) and lowest for both axillary-femoral artery bypass (0.12) and open femoral endarterectomy, thromboembolectomy, or reconstruction (0.12). After adjusting for patient complexity, CEA (O/E = 3.8) and transcarotid artery revascularization (O/E = 2.8) had greater than expected O/E. In contrast, lower extremity bypass (O/E = 0.77), lower extremity embolectomy (O/E = 0.79), and open abdominal aortic repair (O/E = 0.80) had a lower than expected O/E. CONCLUSIONS: Patient complexity varies substantially across vascular procedures and is not captured effectively by wRVUs. Increased operative time for open procedures is not adequately accounted for by wRVUs, which may unfairly penalize surgeons who perform complex open operations.

Patients with depression are less likely to go home after critical limb revascularization.

BACKGROUND: Although often overlooked during the preoperative evaluation, recent evidence has suggested that depression in patients with peripheral artery disease is associated with increased postoperative complications, including decreased primary and secondary patency after revascularization and an increased risk of major amputation and mortality. Postoperative nonhome discharge (NHD) is an important outcome for patients and has also been associated with other adverse outcomes; however, the effect that depression has on NHD after vascular surgery has remained unexplored. We hypothesized that depression would be associated with an increased risk of NHD after revascularization for chronic limb threatening ischemia (CLTI). METHODS: Endovascular, open, and hybrid (combined open and endovascular) cases of revascularization for CLTI were identified from the 2012 to 2014 National (Nationwide) Inpatient Sample. CLTI, diagnoses of depression, and medical comorbidities were defined using the corresponding International Classification of Diseases, Ninth Revision, Clinical Modification codes. A hierarchical multivariable binary logistic regression controlling for hospital level variation and for confounders meeting P <.01 on bivariate analysis was used to examine the association between depression and NHD. A sensitivity analysis after coarsened exact matching for baseline characteristics that differed between the two groups was performed to reduce any imbalance. RESULTS: A total of 64,817 cases were identified, of which 5472 (8.4%) included a diagnosis of depression and 16,524 (25.5%) NHD. The patients with depression were younger and more likely to be women and white, have multiple comorbidities and a nonelective admission, and experience a postoperative complication (P <.05). On unadjusted analyses, patients with depression had an 8% absolute increased risk of requiring NHD (32.1% vs 24.9%; P <.001). On multivariable analysis, patients with depression had an increased odds for NHD (odds ratio [OR], 1.50; 95% confidence interval [CI], 1.40-1.61; c-statistic, 0.81) compared with those without depression. After stratification by operative approach, depression had a larger effect estimate in endovascular revascularization (OR, 1.57; 95% CI, 1.42-1.74) compared with open (OR, 1.45; 95% CI, 1.30-1.62). A test for interaction between depression and gender identified that men with depression had greater odds of NHD compared with women with depression (OR, 1.68; 95% CI, 1.51-1.88; vs OR, 1.37; 95% CI, 1.25-1.51; interaction P <.01). A sensitivity analysis after coarsened exact matching confirmed these findings. CONCLUSIONS: To the best of our knowledge, the present study is the first to identify an association between depression and NHD after revascularization for CLTI. These results provide further evidence of the negative effects that comorbid depression has on patients undergoing revascularization for CLTI. Future studies should examine whether treating depression can improve the outcomes in this patient population.