Hypertension during transfer is associated with poor outcomes in unstable patients with ruptured abdominal aortic aneurysm.

OBJECTIVE: Limited data exist for optimal blood pressure (BP) management during transfer of patients with ruptured abdominal aortic aneurysm (rAAA). This study evaluates the effects of hypertension and severe hypotension during interhospital transfers in a cohort of patients with rAAA in hemorrhagic shock. METHODS: We performed a retrospective, single-institution review of patients with rAAA transferred via air ambulance to a quaternary referral center for repair (2003-2019). Vitals were recorded every 5 minutes in transit. Hypertension was defined as a systolic BP of ≥140 mm Hg. The primary cohort included patients with rAAA with hemorrhagic shock (≥1 episode of a systolic BP of <90 mm Hg) during transfer. The primary analysis compared those who experienced any hypertensive episode to those who did not. A secondary analysis evaluated those with either hypertension or severe hypotension <70 mm Hg. The primary outcome was 30-day mortality. RESULTS: Detailed BP data were available for 271 patients, of which 125 (46.1%) had evidence of hemorrhagic shock. The mean age was 74.2 ± 9.1 years, 93 (74.4%) were male, and the median total transport time from helicopter dispatch to arrival at the treatment facility was 65 minutes (interquartile range, 46-79 minutes). Among the cohort with shock, 26.4% (n = 33) had at least one episode of hypertension. There were no significant differences in age, sex, comorbidities, AAA repair type, AAA anatomic location, fluid resuscitation volume, blood transfusion volume, or vasopressor administration between the hypertensive and nonhypertensive groups. Patients with hypertension more frequently received prehospital antihypertensives (15% vs 2%; P = .01) and pain medication (64% vs 24%; P < .001), and had longer transit times (36.3 minutes vs 26.0 minutes; P = .006). Episodes of hypertension were associated with significantly increased 30-day mortality on multivariable logistic regression (adjusted odds ratio [aOR], 4.71; 95% confidence interval [CI], 1.54-14.39; P = .007; 59.4% [n = 19] vs 40.2% [n = 37]; P = .01). Severe hypotension (46%; n = 57) was also associated with higher 30-day mortality (aOR, 2.82; 95% CI, 1.27-6.28; P = .01; 60% [n = 34] vs 32% [n = 22]; P = .01). Those with either hypertension or severe hypotension (54%; n = 66) also had an increased odds of mortality (aOR, 2.95; 95% CI, 1.08-8.11; P = .04; 58% [n = 38] vs 31% [n = 18]; P < .01). Level of hypertension, BP fluctuation, and timing of hypertension were not significantly associated with mortality. CONCLUSIONS: Hypertensive and severely hypotensive episodes during interhospital transfer were independently associated with increased 30-day mortality in patients with rAAA with shock. Hypertension should be avoided in these patients, but permissive hypotension approaches should also maintain systolic BPs above 70 mm Hg whenever possible.

The association between frailty and outcomes following ruptured abdominal aortic aneurysm repair.

OBJECTIVE: Endovascular aortic repair (EVAR) is a less invasive method than the more physiologically stressful open surgical repair (OSR) for patients with anatomically appropriate abdominal aortic aneurysms (AAAs). Early postoperative outcomes are associated with both patients; physiologic reserve and the physiologic stresses of the surgical intervention. Among frail patients with reduced physiologic reserve, the stress of an aortic rupture in combination with the stress of an operative repair are less well tolerated, raising the risk of complications and mortality. This study aims to evaluate the difference in association between frailty and outcomes among patients undergoing minimally invasive EVAR and the physiologically more stressful OSR for ruptured AAAs (rAAAs). METHODS: Our retrospective cohort study included adults undergoing rAAA repair in the Vascular Quality Initiative from 2010 to 2022. The validated Risk Analysis Index (RAI) (robust, ≤20; normal, 21-29; frail, 30-39; very frail, ≥40) quantified frailty. The association between the primary outcome of 1-year mortality and frailty status as well as repair type were compared using multivariable Cox models generating adjusted hazard ratios (aHRs) with 95% confidence intervals (CIs). Interaction terms evaluated the association's moderation. RESULTS: We identified 5806 patients (age, 72 ± 9 years; 77% male; EVAR, 65%; robust, 6%; normal, 48%; frail, 36%; very, frail 10%) with a 53% observed 1-year mortality rate following rAAA repair. OSR (aHR, 1.43; 95% CI, 1.19-1.73) was associated with increased 1-year mortality when compared with EVAR. Increasing frailty status (frail aHR, 1.26; 95% CI, 1.00-1.59; very frail aHR, 1.64; 95% CI, 1.26-2.13) was associated with increased 1-year mortality, which was moderated by repair type (P-interaction < .05). OSR was associated with increased 1-year mortality in normal (aHR, 1.49; 95% CI, 1.20-1.87) and frail (aHR, 1.51; 95% CI, 1.20-1.89), but not among robust (aHR, 0.88; 95% CI, 0.59-1.32) and very frail (aHR, 1.29; 95% CI, 0.97-1.72) patients. CONCLUSIONS: Frailty and OSR were associated with increased adjusted risk of 1-year mortality following rAAA repair. Among normal and frail patients, OSR was associated with an increased adjusted risk of 1-year mortality when compared with EVAR. However, there was no difference between OSR and EVAR among robust patients who can well tolerate the stress of OSR and among very frail patients who are unable to withstand the surgical stress from rAAA regardless of repair type.

Percutaneous thrombectomy for acute limb ischemia is associated with equivalent limb and mortality outcomes compared with open thrombectomy.

BACKGROUND: Acute limb ischemia (ALI) carries a 15% to 20% risk of combined death or amputation at 30 days and 50% to 60% at 1 year. Percutaneous mechanical thrombectomy (PT) is an emerging minimally invasive alternative to open thrombectomy (OT). However, ALI thrombectomy cases are omitted from most quality databases, limiting comparisons of limb and survival outcomes between PT and OT. Therefore, our aim was to compare in-hospital outcomes between PT and OT using the National Inpatient Sample. METHODS: We analyzed survey-weighted National Inpatient Sample data (2015-2020) to include emergent admissions of aged adults (50+ years) with a primary diagnosis of lower extremity ALI undergoing index procedures within 2 days of hospitalization. We excluded hospitalizations with concurrent trauma or dissection diagnoses and index procedures using catheter-directed thrombolysis. Our primary outcome was composite in-hospital major amputation or death. Secondary outcomes included in-hospital major amputation, death, in-hospital reintervention (including angioplasty/stent, thrombolysis, PT, OT, or bypass), and extended length of stay (eLOS; defined as LOS >75th percentile). Adjusted odds ratios (aORs) with 95% confidence intervals (95% CIs) were generated by multivariable logistic regression, adjusting for demographics, frailty (Risk Analysis Index), secondary diagnoses including atrial fibrillation and peripheral artery disease, hospital characteristics, and index procedure data including the anatomic thrombectomy level and fasciotomy. A priori subgroup analyses were performed using interaction terms. RESULTS: We included 23,795 survey-weighted ALI hospitalizations (mean age: 72.2 years, 50.4% female, 79.2% White, and 22.3% frail), with 7335 (30.8%) undergoing PT. Hospitalization characteristics for PT vs OT differed by atrial fibrillation (28.7% vs 36.5%, P < .0001), frequency of intervention at the femoropopliteal level (86.2% vs 88.8%, P = .009), and fasciotomy (4.8% vs 6.9%, P = .006). In total, 2530 (10.6%) underwent major amputation or died. Unadjusted (10.1% vs 10.9%, P = .43) and adjusted (aOR = 0.96 [95% CI, 0.77-1.20], P = .74) risk did not differ between the groups. PT was associated with increased odds of reintervention (aOR = 2.10 [95% CI, 1.72-2.56], P < .0001) when compared with OT, but this was not seen in the tibial subgroup (aOR = 1.31 [95% CI, 0.86-2.01], P = .21, Pinteraction < .0001). Further, 79.1% of PT hospitalizations undergoing reintervention were salvaged with endovascular therapy. Lastly, PT was associated with significantly decreased odds of eLOS (aOR = 0.80 [95% CI, 0.69-0.94], P = .005). CONCLUSIONS: PT was associated with comparable in-hospital limb salvage and mortality rates compared with OT. Despite an increased risk of reintervention, most PT reinterventions avoided open surgery, and PT was associated with a decreased risk of eLOS. Thus, PT may be an appropriate alternative to OT in appropriately selected patients.

Characterization of multiple organ failure after ruptured abdominal aortic aneurysm repair.

BACKGROUND: Multiple organ failure (MOF) is associated with poor outcomes and increased mortality in sepsis and trauma. There are limited data regarding MOF in patients after ruptured abdominal aortic aneurysm (rAAA) repair. We aimed to identify the contemporary prevalence and characteristics of patients with rAAA with MOF. METHODS: We retrospectively reviewed patients with rAAA who underwent repair (2010-2020) at our multihospital institution. Patients who died within the first 2 days after repair were excluded. MOF was quantified by modified (excluding hepatic system) Denver, Sequential Organ Failure Assessment (SOFA) score, and Multiple Organ Dysfunction Score (MODS) for postoperative days 3 to 5 to determine the prevalence of MOF. MOF was defined as a Denver score of >3, dysfunction in two or more organ systems by SOFA score, or a MODS score of >8. Kaplan-Meier curves and log-rank testing were used to evaluate differences in 30-day mortality between multiple organ failure and patients without MOF. Logistic regression was used to assess predictors of MOF. RESULTS: Of 370 patients with rAAA, 288 survived past two days (mean age, 73±10.1 years; 76.7% male; 44.1% open repair), and 143 had data for MOF calculation recorded. From postoperative days 3 to 5, 41 (14.24%) had MOF by Denver, 26 (9.03%) by SOFA, and 39 (13.54%) by MODS criteria. Among these scoring systems, pulmonary and neurological systems were impacted most commonly. Among patients with MOF, pulmonary derangement occurred in 65.9% (Denver), 57.7% (SOFA), and 56.4% (MODS). Similarly, neurological derangement occurred in 92.3% (SOFA) and 89.7% (MODS), but renal derangement occurred in 26.8% (Denver), 23.1% (SOFA), and 10.3% (MODS). MOF by all three scoring systems was associated with increased 30-day mortality (Denver: 11.3% vs 41.5% [P < .01]; DOFA: 12.6% vs 46.2% [P < .01]; MODS: 12.5% vs 35.9% [P < .01]), as was MOF by any criteria (10.8% vs 35.7 %; P < .01). Patients with MOF were more likely to have a higher body mass index (55.9±26.6 vs 49.0±15.0; P = .011) and to have had a preoperative stroke (17.9% vs 6.0%; P = .016). Patients with MOF were less likely to have undergone endovascular repair (30.4% vs 62.1%; P < .001). Endovascular repair was protective against MOF (any criteria) on multivariate analysis (odds ratio, 0.23; 95% confidence interval, 0.08-0.64; P = .019) after adjusting for age, gender, and presenting systolic blood pressure. CONCLUSIONS: MOF occurred in only 9% to 14% of patients after rAAA repair, but was associated with a three-fold increase in mortality. Endovascular repair was associated with a reduced MOF incidence.

MetfOrmin BenefIts Lower Extremities with Intermittent Claudication (MOBILE IC): randomized clinical trial protocol.

BACKGROUND: Peripheral artery disease (PAD) affects over 230 million people worldwide and is due to systemic atherosclerosis with etiology linked to chronic inflammation, hypertension, and smoking status. PAD is associated with walking impairment and mobility loss as well as a high prevalence of coronary and cerebrovascular disease. Intermittent claudication (IC) is the classic presenting symptom for PAD, although many patients are asymptomatic or have atypical presentations. Few effective medical therapies are available, while surgical and exercise therapies lack durability. Metformin, the most frequently prescribed oral medication for Type 2 diabetes, has salient anti-inflammatory and promitochondrial properties. We hypothesize that metformin will improve function, retard the progression of PAD, and improve systemic inflammation and mitochondrial function in non-diabetic patients with IC. METHODS: 200 non-diabetic Veterans with IC will be randomized 1:1 to 180-day treatment with metformin extended release (1000 mg/day) or placebo to evaluate the effect of metformin on functional status, PAD progression, cardiovascular disease events, and systemic inflammation. The primary outcome is 180-day maximum walking distance on the 6-min walk test (6MWT). Secondary outcomes include additional assessments of functional status (cardiopulmonary exercise testing, grip strength, Walking Impairment Questionnaires), health related quality of life (SF-36, VascuQoL), macro- and micro-vascular assessment of lower extremity blood flow (ankle brachial indices, pulse volume recording, EndoPAT), cardiovascular events (amputations, interventions, major adverse cardiac events, all-cause mortality), and measures of systemic inflammation. All outcomes will be assessed at baseline, 90 and 180 days of study drug exposure, and 180 days following cessation of study drug. We will evaluate the primary outcome with linear mixed-effects model analysis with covariate adjustment for baseline 6MWT, age, baseline ankle brachial indices, and smoking status following an intention to treat protocol. DISCUSSION: MOBILE IC is uniquely suited to evaluate the use of metformin to improve both systematic inflammatory responses, cellular energetics, and functional outcomes in patients with PAD and IC. TRIAL REGISTRATION: The prospective MOBILE IC trial was publicly registered (NCT05132439) November 24, 2021.

Selective Publication within Vascular Surgery: Characteristics of Discontinued and Unpublished Randomized Clinical Trials.

BACKGROUND: Discontinued and unpublished randomized clinical trials (RCTs) are common resulting in biased publication and loss of potential knowledge. The magnitude of selective publication within vascular surgery remains unknown. METHODS: RCT relevant to vascular surgery registered (01/01/2010-10/31/2019) on ClinicalTrials.gov were included. Trials ending normally with conclusion of participant treatment and examination were considered completed whereas discontinued trials stopped early. Publications were identified through automatically indexed PubMed citations on ClinicalTrials.gov or manually identified on PubMed or Google Scholar >30 months after the completion date, the date the final participant was examined, allowing time for publication. RESULTS: Of 108 RCT (n = 37, 837), 22.2% (24/108) were discontinued, including 16.7% (4/24) stopped prior to and 83.3% (20/24) after starting enrollment. Only 28.4% of estimated enrollment was achieved for all discontinued RCT. Nineteen (79.2%) investigators provided a reason for discontinuation, which most commonly included poor enrollment (45.8%), inadequate supplies or funding (12.5%), and trial design concerns (8.3%). Of the 20 trials terminated following enrollment, 20.0% (4/20) were published in peer-reviewed journals and 80.0% (16/20) failed to reach publication. Of the 77.8% trials completed, 75.0% (63/84) were published and 25.0% (21/84) remain unpublished. In a multivariate regression of completed trials, industry funding was significantly associated with decreased likelihood of peer-reviewed publication (OR = 0.18, (95% CI 0.05-0.71), P = 0.01). Of the discontinued and completed trials remaining unpublished, 62.5% and 61.9% failed to report results on ClinicalTrials.gov, respectively, encompassing a total of 4,788 enrollees without publicly available results. CONCLUSIONS: Nearly 25% of registered vascular RCT were discontinued. Of completed RCT, 25% remain unpublished with industry funding associated with decreased likelihood of publication. This study identifies opportunities to report all findings for completed and discontinued vascular surgery RCT, whether industry sponsored, or investigator initiated.

A 22-year analysis of the Society for Vascular Surgery Foundation Mentored Research Career Development Award in fostering vascular surgeon-scientists.

OBJECTIVE: Vascular surgeon-scientists shape the future of our specialty through rigorous scientific investigation and innovation in clinical care and by training the next generation of surgeon-scientists. The Society for Vascular Surgery Foundation (SVSF) supports the development of surgeon-scientists through the Mentored Research Career Development Award (SVSF-CDA) program, providing supplemental funds to recipients of National Institutes of Health (NIH) K08/K23 grants. We evaluated the ongoing success of this mission. METHODS: The curriculum vitae of the 41 recipients of the SVSF supplemental funding from 1999 to 2021 were collected and reviewed to evaluate the academic achievements, define the programmatic accomplishments and return on investment, and identify areas for strategic improvement. RESULTS: For nearly 22 years, the SVSF has awarded supplemental funds for 31 K08 and 10 K23 grants to SVS members from 32 institutions. Of the 41 awardees, 34 have completed their K-funding and 7 are still being supported. Eleven awardees (27%) were women, including six of the current awardees (75%). However, only slight ethnic/racial diversity was found in the program. The awardees had obtained K-funding ∼4 years after becoming faculty. Eleven awardees (27%) were supported by Howard Hughes, NIH F32, or NIH T32 grants during training. To date, the SVSF has committed $12 million to the SVSF-CDA program. Among the 34 who have completed their K-funding, 21 (62%) successfully obtained NIH R01, Veterans Affairs, or Department of Defense funding. The awardees have secured >$114 million in federal funding, representing a 9.5-fold financial return on investment for the SVSF. In addition to research endeavors, 11 awardees (27%) hold endowed professorships and 19 (46%) have secured tenure at their institution. Many of the awardees hold or have held leadership positions, including 18 division chiefs (44%), 11 program directors (27%), 5 chairs of departments of surgery (12%), and 1 dean (2%). Eleven (27%) have served as president of a regional or national society, and 24 (59%) participate in NIH study sections. Of the 34 who have completed their K-funding, 15 (44%) have continued to maintain active independent research funding. CONCLUSIONS: The SVSF-CDA program is highly effective in the development of vascular surgeon-scientists who contribute to the leadership and growth of academic vascular surgery with a 9.5-fold return on investment. The number of female awardees has increased in recent years but ethnic/racial diversity has remained poor. Although 62% successfully transitioned to federal funding, fewer than one half have remained funded over time. Retention in research and increasing diversity for the awardees are major concerns and important areas of strategic focus for the SVSF.

Characterization of immediate and early mortality after repair of ruptured abdominal aortic aneurysm.

BACKGROUND: We sought to compare immediate and early mortality among patients undergoing ruptured abdominal aortic aneurysm (RAAA) repair. Evaluation of RAAA has focused on 30-day postoperative mortality. Other emergency conditions such as trauma have demonstrated a multimodal mortality distribution within the 30-day window, expanding the pathophysiologic understanding and allowing for intervention investigations with practice changing and lifesaving results. However, the temporal distribution and risk factors of postoperative morbidity and mortality in RAAA have yet to be investigated. METHODS: We evaluated factors associated with RAAA postoperative mortality in immediate (<1 day) and early (1-30 days) postoperative periods in a landmarked retrospective cohort study using data from the Vascular Quality Initiative (2010-2020). RESULTS: We identified 5157 RAAA repairs (mean age, 72 ± 10 years; 77% male; 88% White; 61% endovascular). The mortality rate in the immediate period was 10.2% (528/5157) and the early mortality rate was 22.1% (918/4163). In multivariable regression analyses, signs of hemorrhagic shock (ie, hemoglobin <7 g/dL: adjusted odds ratio [aOR], 1.87 [95% confidence interval [CI], 1.14-3.06]; any preoperative systolic blood pressure <70 mm Hg: aOR, 1.40 [95% CI, 1.04-1.89]; and estimated blood loss >40%: aOR, 3.65 [95% CI, 2.29-5.83]) were associated with an increased risk of immediate mortality. Comorbid conditions (heart failure: aOR, 1.38 [95% CI, 1.00-1.92]; pulmonary disease: aOR, 1.29 [95% CI, 1.05-1.58]; elevated creatinine: aOR 1.26 [95% CI, 1.31-1.41]) were associated with increased risk of early mortality. CONCLUSIONS: Immediate deaths were associated predominantly with shock from massive hemorrhage, whereas early deaths were associated with comorbid conditions predisposing patients to multisystem organ failure despite successful repair. These temporal distinctions should guide future mechanistic and intervention evaluations to improve RAAA mortality.

Epidemiology of age-, sex-, and race-specific hospitalizations for abdominal aortic aneurysms highlights gaps in current screening recommendations.

BACKGROUND: The detection and elective repair of abdominal aortic aneurysms (AAA) guided by known risk-factor specific screening decrease AAA-related mortality. However, minimal epidemiologic data exist for AAA in female persons and racial minority groups. We established the contemporary risk of US AAA hospitalization across age, sex, and race. METHODS: National Inpatient Sample and US Census (2012-2018) data were used to quantify age-, sex-, and race-specific incidences and adjusted odds ratios (aOR) of AAA hospitalizations (≥18 years), associated risk factors, and in-hospital mortality. Interaction terms evaluated subgroups. RESULTS: Among 1,728,374,183 US residents during the study period (51.3% female; 78.4% White, 12.7% Black, 5.7% Asian), 211,501,703 were hospitalized (aged 57.56 ± 0.04 years; 58.4% female; 64.9% White, 14.3% Black, 2.5% Asian) of which 291,850 were for AAA (aged 73.17 ± 0.04 years; 22.6% female; 81.8% White, 5.6% Black, 1.6% Asian). An estimated 15.2 (95% CI, 15.1-15.3) and 1.7 (95% CI, 1.7-1.7) hospitalizations per 100,000 residents were for intact AAA (iAAA) and ruptured AAA (rAAA) AAA, respectively. In addition, 16.2% of iAAA (83.8% male; 79.1% White) and 18.4% of rAAA (86.4% male; 75.0% White) hospitalizations occurred in patients less than 65 years of age. For iAAA, female sex (aOR, 0.27; 95% CI, 0.27-0.28) compared with male sex and both Black (0.47; 95% CI, 0.45-0.49) and Asian (0.86; 95% CI, 0.83-0.93) persons compared with White persons had a reduced aOR for hospitalization. For rAAA, the reduced aOR persisted for female sex (0.33; 95% CI, 0.32-0.36) and for Black persons (0.52; 95% CI, 0.46-0.58). Although female sex demonstrated an overall decreased odds of AAA hospitalization, female persons who were older, Black, or had peripheral vascular disease (Pinteractions < .001) had a relative increase in AAA hospitalization aOR. Female sex (aOR, 1.54; 95% CI, 1.38-1.70), but not Black or Asian race, was associated with increased mortality which was more pronounced for iAAA (1.93; 95% CI, 1.66-2.25) than rAAA (1.29; 95% CI, 1.13-1.48]; Pinteraction < .001). CONCLUSIONS: We confirmed a substantially decreased adjusted risk of AAA hospitalization for females and racial minority groups; however, aging and comorbid peripheral vascular disease decreased these differences. The disparate risk of AAA hospitalization by sex and race highlights the importance of inclusivity in future AAA studies.

Longer follow-up intervals following endovascular aortic aneurysm repair are safe and appropriate after marked aneurysm sac regression.

BACKGROUND: Abdominal aortic aneurysm (AAA) shrinkage after endovascular aortic aneurysm repair (EVAR) is a surrogate marker for successful exclusion. Our study characterized aneurysm sac remodeling after EVAR to identify a pattern that may be associated with benign AAA behavior and would safely allow a less rigorous follow-up regimen after EVAR. METHODS: Elective infrarenal EVARs performed between 2008 and 2011 at our institution were retrospectively reviewed. AAA sac diameters using the minor axis measurement from ultrasound imaging or computer tomography angiogram imaging were compared with the baseline diameter from the 1-month postoperative computer tomography angiogram. The primary outcome was a composite of freedom from postoperative reintervention or rupture. We compared those with AAA sacs who regressed to predefined minimum diameter thresholds with those who did not. Outcomes were plotted with Kaplan-Meier curves and compared using log-rank testing and Fine-Gray regression using death as a competing risk, clustered on graft type. For patients whose AAA reached the minimum sac diameter, landmark analysis evaluated ongoing size changes including further regression and sac re-expansion. RESULTS: A total of 540 patients (aged 75.1 ± 8.2 years; 82.0% male) underwent EVAR with an average preoperative AAA size of 55.2 ± 11.5 mm. The median postoperative follow-up was 5.3 years (interquartile range, 1.4-8.7 years) during which 64 patients underwent reintervention and 4 ruptured. AAA sac regression to ≤40 mm in diameter was associated with improved freedom from reintervention or rupture overall (log-rank, P < .01), which was maintained after controlling for the competing risk of death (P < .01). In 376 patients (70%) whose aneurysm sac remained >40 mm, 99 reinterventions were performed on 63 patients. Of 166 (31%) patients whose sac regressed to ≤40 mm, only 1 patient required a reintervention, and no one ruptured. The mean time to a diameter of ≤40 mm was 2.3 ± 1.9 years. Only eight patients (5%) developed sac re-expansion to >45 mm; all but two occurred at least 3 years after initially regressing to ≤40 mm. CONCLUSIONS: In long-term follow-up, patients whose minimum AAA sac diameter regressed ≤40 mm after EVAR experienced a very low rate of reintervention, rupture, or sac re-expansion. Most sac re-expansion occurred at least 3 years after reaching this threshold and did not result in clinical events. Increasing follow-up frequency up to 3-year intervals once the AAA sac regresses to 40 mm would carry minimal risk of aneurysm-related morbidity.

Updated research priorities of the Society for Vascular Surgery.

In 2011, the Society for Vascular Surgery (SVS) prepared a set of clinical research priorities through a survey of its membership. These priorities were developed with the goal of enhancing clinical research to improve care for vascular patients. In the subsequent decade, several of these priorities served as the focus of clinical trials and significant research efforts. It was understood from the outset that this list of priorities represented a starting point with the intention that they be reevaluated at suitable intervals. In 2021, the SVS Research Council set out to update the research priorities by surveying the SVS membership and engaged a panel of subject matter experts. This process resulted in an updated set of vascular research priorities that more clearly align with current areas of emphasis. Our priorities remain focused on basic areas including aortic disease, carotid disease, lower extremity arterial disease, venous disease, dialysis access, and medical management of vascular disease, along with the topic of health care disparities. The 10 updated priorities reported herein reflect our increasing awareness of the need to understand vascular disease pathogenesis and prevention in the context of a diverse patient population. Importantly, patient-centered outcomes and personalized vascular care are at the core of these updated priorities. Similar to the aims of the original 2011 clinical research priorities, our hope is that this updated list will help to drive large-scale investigations that will improve how we care for our vascular patients.

Factors associated with preference of choice of aortic aneurysm repair in the PReference for Open Versus Endovascular repair of AAA (PROVE-AAA) study.

OBJECTIVE: Patients can choose between open repair and endovascular repair (EVAR) of abdominal aortic aneurysm (AAA). However, the factors associated with patient preference for one repair type over another are not well-characterized. Here we assess the factors associated with preference of choice for open or endovascular AAA repair among veterans exposed to a decision aid to help with choosing surgical treatment. METHODS: Across 12 Veterans Affairs hospitals, veterans received a decision aid covering domains including patient information sources and understanding preference. Veterans were then given a series of surveys at different timepoints examining their preferences for open versus endovascular AAA repair. Questions from the preference survey were used in analyses of patient preference. Results were analyzed using χ2 tests. A logistic regression analysis was performed to assess factors associated with preference for open repair or preference for EVAR. RESULTS: A total of 126 veterans received a decision aid informing them of their treatment choices, after which 121 completed all preference survey questions; five veterans completed only part of the instruments. Overall, veterans who preferred open repair were typically younger (70 years vs 73 years; P = .02), with similar rates of common comorbidities (coronary disease 16% vs 28%; P = .21), and similar aneurysms compared with those who preferred EVAR (6.0 cm vs 5.7 cm; P = .50). Veterans in both preference categories (28% of veterans preferring EVAR, 48% of veterans preferring open repair) reported taking their doctor's advice as the top box response for the single most important factor influencing their decision. When comparing the tradeoff between less invasive surgery and higher risk of long-term complications, more than one-half of veterans preferring EVAR reported invasiveness as more important compared with approximately 1 in 10 of those preferring open repair (53% vs 12%; P < .001). Shorter recovery was an important factor for the EVAR group (74%) and not important in the open repair group (76%) (P = .5). In multivariable analyses, valuing a short hospital stay (odds ratio, 12.4; 95% confidence interval, 1.13-135.70) and valuing a shorter recovery (odds ratio, 15.72; 95% confidence interval, 1.03-240.20) were associated with a greater odds of preference for EVAR, whereas finding these characteristics not important was associated with a greater odds of preference for open repair. CONCLUSIONS: When faced with the decision of open repair versus EVAR, veterans who valued a shorter hospital stay and a shorter recovery were more likely to prefer EVAR, whereas those more concerned about long-term complications preferred an open repair. Veterans typically value the advice of their surgeon over their own beliefs and preferences. These findings need to be considered by surgeons as they guide their patients to a shared decision.

Consensus Current Procedural Terminology Code Definition of Source Control for Sepsis.

INTRODUCTION: Unlike antibiotic and perfusion support, guidelines for sepsis source control lack high-quality evidence and are ungraded. Internally valid administrative data methods are needed to identify cases representing source control procedures to evaluate outcomes. METHODS: Over five modified Delphi rounds, two independent reviewers identified Current Procedural Terminology (CPT) codes pertinent to source control. In each round, codes with perfect agreement were retained or excluded, whereas disagreements were reviewed by the panelists. Manual review of 400 patient records meeting Sepsis-3 criteria (2010-2017) clinically adjudicated which encounters included source control procedures (gold standard). The performance of consensus codes was compared with the gold standard to assess sensitivity, specificity, predictive values, and likelihood ratios. RESULTS: Of 5752 CPT codes, 609 consensus codes represented source control procedures. Of 400 hospitalizations for sepsis, 39 (9.8%; 95% confidence interval [CI] 7.0%-13.1%) underwent gold standard source control procedures and 29 (7.3%; 95% CI 4.9-10.3%) consensus code-defined source control procedures. Thirty consensus codes were identified (20.0% gastrointestinal/intraabdominal, 10.0% genitourinary, 13.3% hepatopancreatobiliary, 23.3% orthopedic/cranial, 23.3% soft tissue, and 10.0% intrathoracic), which had 61.5% (95% CI 44.6%-76.6%) sensitivity, 98.6% (95% CI 96.8%-99.6%) specificity, 83.2% (95% CI 66.6%-92.4%) positive, and 95.9% (95% CI 93.9%-97.2%) negative predictive values. With pretest probability at sample prevalence, an identified consensus code had a posttest probability of 83.0% (95% CI 66.0%-92.0%), whereas consensus code absence had a probability of 4.0% (95% CI 3.0-6.0) for undergoing a source control procedure. CONCLUSIONS: Using modified Delphi methodology, we created and validated CPT codes identifying source control procedures, providing a framework for evaluation of the surgical care of patients with sepsis.

The Impact of Work Status and Age in Choosing Type of Abdominal Aortic Aneurysm Repair.

INTRODUCTION: The PReferences for Open Versus Endovascular Repair of Abdominal Aortic Aneurysm (PROVE-AAA) trial aimed to determine the efficacy of a validated decision aid to enable better alignment between patient preference and their ultimate repair. We sought to determine the key factors influencing the decision-making of veterans for endovascular repair of abdominal aortic aneurysm (EVAR) or open surgical repair (OSR). METHODS: A total of 235 veterans in the PROVE-AAA trial were asked their information sources regarding repairs, employment status, and preferred intervention. Answers were coded and analyzed using conventional content analysis to generate nonoverlapping themes, then stratified by employment status. RESULTS: Forty-two patients (17.8% of enrollees) provided their source of information for OSR prior to using a decision aid. 81% of retired veterans were greater than 70 y old, while 58% of nonretired veterans were greater than 70 (P = 0.003). The most common information source was from a vascular surgeon/professional or unspecified MD/other health professionals (51.4%), while sources from outside this group made up the remaining 48.5%. The most preferred procedure was EVAR. However, nonretired individuals were more likely to prefer OSR. These data on information source and preferred procedure were similar in patients who provided their source for EVAR. CONCLUSIONS: Veterans in the PROVE-AAA study were more likely to be retired and more likely to rely on information from an unspecified MD/other health professionals for EVAR. Although both retired and nonretired veterans preferred EVAR the most, nonretired veterans were more likely to prefer OSR despite being younger.

Outcomes after Elective Abdominal Aortic Aneurysm Repair Have Improved Over Time in Patients on Dialysis.

BACKGROUND: Prior studies have demonstrated poor perioperative and long-term survival of patients with end-stage kidney disease (ESKD) on dialysis who undergo abdominal aortic aneurysm repair (AAAR). However, survival in dialysis patients overall has improved over time. We hypothesize that the contemporary rates of perioperative and long-term survival following AAAR in ESKD patients are also improving. METHODS: Data on AAAR procedures in dialysis patients were collected from the United States Renal Data System between 2008 and 2017. Endovascular (EVAR) and open AAA repair (OAR) were identified by Current Procedural Terminology codes. Patients with a functioning renal transplant, a ruptured aneurysm, and insurance other than Medicare were excluded. Demographics, comorbidities, procedural details, and long-term outcomes were collected. Standard statistical methods were used. RESULTS: We identified 3,374 patients who underwent EVAR (86%, 2,914/3,374) and OAR (14%, 460/3,374). The utilization of OAR decreased significantly from 2008 to 2017 (17.34% vs. 7.43%, P < 0.001). Kaplan-Meier survival analysis revealed no significant difference in 5-year survival between OAR and EVAR (24% vs. 17%, P = 0.1, Wilcoxon-Breslow test), but open repair was associated with increased long-term survival (Hazards ratio 0.994, confidence interval 0.990-0.999, P = 0.017) in an adjusted Cox regression model. The cohort was then divided based on the year of AAAR, group 1: 2008-2010 (1,269/3,374), group 2: 2011-2013 (1,071/3,374), and group 3: 2014-2017 (1,034/3,374). Compared to groups 1 and 2, Group 3 was less likely to have coronary artery device, peripheral vascular disease, recent pneumonia, be nonambulatory, live in a nursing facility, or undergo an OAR and more likely to be younger and dialyze through an arteriovenous fistula/arteriovenous graft at the time of AAA repair. Thirty-day postoperative mortality was significantly lower in group 3 compared to groups 1 and 2 (5.4% [56/1,034] vs. 10.3% [131/1,269]/7.3% [78/1,071], P < 0.031). One-year survival by Kaplan-Meier estimate was significantly higher in group 3 (77.7% [803/1,034]) versus groups 1 and 2 (56.7% [719/1,269], 66.9% [716/1,071], P < 0.001, log-rank test). Five-year survival was also significantly higher in group 3 (27.3%) compared to groups 1 and 2 (14.2% and 16.5%, P < 0.001, log-rank test). In a Cox regression model of long-term mortality adjusted for variables significant on a univariate testing, more recent procedure year was associated with increased survival (Hazards ratio 0.81, [0.77, 0.85], P < 0.001). CONCLUSIONS: Postoperative and long-term survival following AAA repair have increased over time in ESKD patients on dialysis. This increased survival persists after accounting for differences in patient demographics and type of procedure over time. Elective AAA repair should be considered in carefully selected good-risk patients on dialysis.

Any Postoperative Surveillance Improves Survival after Endovascular Repair of Ruptured Abdominal Aortic Aneurysms.

BACKGROUND: Endovascular aortic repair (EVAR) has advanced the care of patients with ruptured abdominal aortic aneurysms (rAAA) with improved early postoperative morbidity and mortality. However, this comes at the cost of a rigorous postoperative surveillance schedule to monitor for further aneurysmal degeneration. Adherence to surveillance recommendations is known to be poor in the elective setting, but has yet to be studied in the ruptured population. The aim of this study is to investigate predictors of incomplete surveillance after EVAR for rAAA (rEVAR) and examine how adherence impacts outcomes. METHODS: This was a retrospective case control study of patients undergoing rEVAR at a multiple hospital single healthcare center (2003-2020). Patients were excluded if they underwent open conversion during their index hospitalization or died within 60 days of surgery. Follow-up was broadly categorized as complete surveillance (60-day postoperative visit and annually thereafter) or incomplete surveillance, comprising both patients with less than recommended surveillance (minimal surveillance) and completely lost to follow-up (LTF). Any follow-up was defined as patients with complete or minimal surveillance. We investigated predictors of complete versus incomplete surveillance by multivariate logistic regression. Secondary outcomes included overall survival and cumulative incidence of reintervention controlling for the competing risk of mortality, generating hazard ratios (HR) and subdistribution hazard ratios (SHR). RESULTS: One-hundred and sixty patients (mean age 74 ± 10.1 years, 81.2% male) out of 673 total rAAA met study inclusion criteria. Complete surveillance was seen in 41.3% of our cohort, with the remainder with minimal surveillance (29.4%) or LTF (29.4%). Incomplete surveillance was associated with male sex (odds ratio [OR] 2.56; 95% CI 1.02-6.43), lack of a primary care provider (PCP; OR 0.20; 95% CI 0.04-0.99), and longer driving distance from home to treating hospital (OR 2.37; 95% CI 1.08-5.20). Survival was not different between complete and incomplete surveillance groups, however any follow-up conferred improved survival over LTF (HR 0.57; 95% CI 0.331-0.997; P = 0.049). Reintervention was associated with incomplete surveillance (SHR 0.29; 95% CI 0.11-0.75), and discharge to a facility (SHR 0.25; 95% CI 0.067-0.94). CONCLUSIONS: Incomplete surveillance was observed in over 50% of patients who underwent rEVAR and was associated with male sex, lack of PCP, and longer driving distance. Any follow-up conferred a survival benefit, yet incomplete surveillance was associated with a lower risk of reintervention. Targeted strategies to prevent LTF, and less stringent, personalized follow-up plans that may confer similar survival benefit with better patient adherence should be investigated.

The Correlation Between Case Total Work Relative Value Unit, Operative Stress, and Patient Frailty: Retrospective Cohort Study.

OBJECTIVE: Assess the relationships between case total work relative value units (wRVU), patient frailty, and the physiologic stress of surgical interventions. SUMMARY OF BACKGROUND DATA: Surgeon reimbursement is frequently apportioned by wRVU. These subjective, procedure-specific valuations generated by physician survey estimate the intensity and time for typical patient care services. We hypothesized wRVU would not adequately account for patient-specific factors, such as frailty, that modify the required physician work, regardless of procedural complexity. METHODS: Using National and Veterans Affairs Surgical Quality Improvement Programs (2015-2018), we evaluated the correlation between case total wRVU, patient frailty (risk analysis index) and physiologic surgical stress (operative stress score). RESULTS: Of 4,111,371 (86%) cases, the correlation between total wRVU and operative stress was moderate [ρs = 0.587 (95% confidence interval, 0.586-0.587)], but negligible with frailty ρ = 0.177 (95% confidence interval, 0.176-0.178)]. Very high operative stress procedures [n = 34,047 (1%)] generated a mean total wRVU of 55.1 (standard deviation, 12.9), comprising 7%, 2%, and 1% of thoracic, vascular, and general surgical cases, respectively. Very frail patients [n = 152,535 (4%)] accounted for 9% of thoracic, 9% of vascular, 4% of general, 5% of urologic, and 4% of neurologic surgical cases, generating 21.0 (standard deviation, 12.4) mean total wRVU. Some nonfrail patients undergoing low operative stress procedures [n = 60,128 (2%)] nonetheless generated the highest quintile wRVU; these comprised >15% of plastic, gynecologic, and urologic surgical cases. CONCLUSIONS: Surgeon reimbursement correlates with operative stress but not patient frailty. The total wRVU does not adequately reflect patient-specific factors that increase the physician workload required to render optimal care to complex patients.

Patient information sources when facing repair of abdominal aortic aneurysm.

OBJECTIVE: Shared medical decision making is most important when there are competing options for repair such as in treatment of abdominal aortic aneurysm (AAA). We sought to understand the sources of patients' pre-existing knowledge about AAA to better inform treating physicians about patients' needs for preoperative counseling. METHODS: We performed a multicenter survey of patients facing AAA repair at 20 Veterans Affairs hospitals across the United States as part of the Preferences for Open Versus Endovascular Repair of AAA study. A validated survey instrument was administered to examine the sources of information available and commonly used by patients to learn about their repair options. The survey was administered by study personnel before the patient had any interaction with the vascular surgeon because survey data were collected before the vascular clinic visit. RESULTS: Preliminary analysis of data from 99 patients showed that our cohort was primarily male (99%) and elderly (mean age 73 years). Patients commonly had a history of hypertension (86%), prior myocardial infarction (32%), diabetes (32%), and were overweight (58%). Patients arrived at their surgeon's office appointment with limited information. A majority of patients (52%) reported that they had not talked to their primary care physician at all about their options for AAA repair, and one-half (50%) reported that their view of the different surgical options had not been influenced by anyone. Slightly less than one-half of patients reported that they did not receive any information about open surgical aneurysm repair and endovascular aortic aneurysm repair (41% and 37%, respectively). Few patients indicated using the internet as their main source of information about open surgical aneurysm repair and endovascular aortic aneurysm repair (10% and 11%, respectively). CONCLUSIONS: Patients are commonly referred for AAA repair having little to no information regarding AAA pathology or repair options. Fewer than one in five patients searched the internet or had accessed other sources of information on their own. Most vascular surgeons should assume that patients will present to their first vascular surgery appointment with minimal understanding of the treatment options available to them.

Systemic vasoprotection by inhaled carbon monoxide is mediated through prolonged alterations in monocyte/macrophage function.

Carbon monoxide (CO) is anti-inflammatory and protective in models of disease. Its actions in vitro are short-lived but are sustained in vivo. We hypothesize that systemic CO can mediate prolonged phenotype changes in vivo, with a focus on macrophages (Mφs). Mφs isolated from CO treated rats responded to lipopolysaccharide (LPS) with increased IL6, IL10 and iNOS expression but decreased TNF. Conditioned media (CM) collected from peritoneal Mφs isolated from CO treated rats stimulated endothelial cell (EC) proliferation versus CM from Mφs from air treated rats. This effect was mediated by Mφ released VEGF and HMGB1. Inhaled CO reduced LPS induced Mφ M1 inflammatory phenotype for up to 5 days. Mitochondrial oxygen consumption in LPS treated Mφs from CO treated mice was preserved compared to LPS treated Mφs from control mice. Finally, transient reduction of inflammatory cells at the time of inhaled CO treatment eliminated the vasoprotective effect of CO in a rodent carotid injury model. Thus, inhaled CO induces a prolonged mixed phenotype change in Mφs, and potentially other inflammatory cells, that contribute to vasoprotection. These findings demonstrate the ability of inhaled CO to modify Mφs in a sustained manner to mediate its therapeutic actions, supporting the translational potential of inhaled CO.

Inferior Mid-term Durability with Comparable Survival for Younger Patients Undergoing Elective Endovascular Infrarenal versus Open Abdominal Aortic Aneurysm Repair.

BACKGROUND: The durability of endovascular aneurysm repair (EVAR) when compared to open surgical repair (OSR) in younger patients for elective, infrarenal abdominal aortic aneurysms (AAA) remains unclear due to limited follow-up. METHODS: We identified all patients <70 years of age who underwent elective, de novo EVAR or OSR for infrarenal AAA from 2003 to 2013 in a multihospital, single institution. Baseline patient clinical and aneurysmal characteristics were adjusted for using multivariable Cox proportional hazards models and negative binomial regression. RESULTS: We identified 253 patients: 204 underwent EVAR (80.6%) and 49 OSR (19.4%). Baseline demographics and comorbidities were similar across groups. There were no deaths in the immediate perioperative period. The rate of new arrhythmia (EVAR: 1.0%, OSR: 10.2%; P = 0.004), median hospital length of stay (EVAR: 1 day, OSR: 5 days; P < 0.001), and discharge to a facility (EVAR: 2.9%, OSR: 12.2%; P = 0.016) were significantly increased for OSR. In both groups, median follow-up time was 4.5 years, in which survival did not differ between groups. The hazard of composite of freedom from death and any reinterventions (hazard ratio [HR] 4.3, P = 0.009), freedom from any reintervention (relative risk [RR] 4.08, P = 0.030), and freedom from any endovascular reintervention (RR 4.83, P = 0.038) were each higher for OSR when compared to EVAR. EVAR of the standard instruction for use (IFU) for neck length was more likely to die or undergo a reintervention (HR 4.90, P = 0.001). CONCLUSIONS: Our retrospective review of younger patients undergoing elective AAA repair demonstrated no significant differences in perioperative mortality or survival over time between EVAR and OSR. EVAR required more total reinterventions and endovascular reintervention when compared to OSR.