A Decade's Experience with Retrograde Open Mesenteric Stenting for Acute Mesenteric Ischemia.

OBJECTIVE: Retrograde open mesenteric stenting (ROMS) is an alternative to mesenteric bypass in patients with acute mesenteric ischemia (AMI) with variable reported 30-day mortality rates. Large studies evaluating patient outcomes following ROMS are scarce. Our study aims to assess the results of this approach among patients presenting with AMI. METHODS: We reviewed all the patients with AMI who were treated with ROMS (2011-2022). Patient demographics, presentation, operative details, and outcomes were analyzed. Primary endpoints were in-hospital, 30-day and 1-year mortality. Kaplan-Meier estimate for 1-year mortality and primary patency loss were generated. Secondary endpoints included postoperative 30-day complications. RESULTS: Between 2011 and 2022, ROMS was attempted on a total of 42 patients. The median age was 70 ±15 years and the majority of patients were female. Pain out of proportion to the physical exam was the most common presenting symptom (n=18 ,42.9%) followed by peritonitis (n= 14, 33.4%). All patients had pre-operative IV contrast computed tomography imaging. In-situ thrombosis was identified as the etiology of AMI in 36 (85.7%) patients. Technical success was achieved in 40 (95.2%) patients. Conventional, non-hybrid operating rooms were utilized for the majority of cases. Revascularization of all 40 patients involved angioplasty and stenting of superior mesenteric artery (SMA): A single stent was placed in 35 (87.5%) patients and the reminder had more than one stent. 80% of patients required bowel resection. A second-look laparotomy was required in 34 (85.0%) patients. The mean operative time, including both the general surgery and vascular surgery portions of the index procedure, was 192 ± 57 minutes. Sepsis was the most common complication observed within 30 days, occurring in 8 (20.0%) patients. In terms of mortality, 13 (32.5%) patients died during their index hospitalization, while 9 (22.5%) died within 30 days. On Kaplan-Meier analysis, the 1-year overall patient survival rate was 58.6%, and the primary patency rate for stents was 51.4%. CONCLUSION: ROMS has excellent technical success rate in management of AMI with lower than traditionally reported mortality rates for AMI. The dual benefits of rapid revascularization and bowel evaluation should make this surgical modality an alternative approach for treatment of AMI.

Midterm outcomes and predictors of failure of lower extremity bypass to para-malleolar and pedal targets.

OBJECTIVES: The frequency of distal lower extremity bypass (LEB) for infra-popliteal critical limb threatening ischemia (IP-CLTI) has significantly decreased. Our goal was to analyze the contemporary outcomes and factors associated with failure of LEB to para-malleolar and pedal targets. METHODS: We queried the VQI infra-inguinal database from 2003-2021 to identify LEB to para-malleolar or pedal/plantar targets. Primary outcomes were graft patency, major adverse limb events [vascular re-intervention, above ankle amputation] (MALE), and amputation-free survival at 2 years. Standard statistical methods were utilized. RESULTS: We identified 2331 LEB procedures (1265 anterior tibial at ankle/dorsalis pedis, 783 posterior tibial at ankle, 283 tarsal/plantar). The prevalence of LEB bypasses to distal targets has significantly decreased from 13.37% of all LEB procedures in 2003 to 3.51% in 2021 (p<0.001). The majority of cases presented with tissue loss (81.25. Common post-operative complications included major adverse cardiac events (8.9%) and surgical site infections (3.6%). Major amputations occurred in 16.8% of patients at 1 year. Post-operative mortality at 1 year was 10%. On unadjusted Kaplan-Meier survival analysis at 2 years, primary patency was 50.56%±3.6%, MALE was 63.49%±3.27%, and amputation-free survival was 71.71%±0.98%. In adjusted analyses [adjusted for comorbidities, indication, conduit type, urgency, prior vascular interventions, graft inflow vessel (femoral/popliteal), concomitant inflow procedures, surgeon and center volume] conduits other than GSV (p<0.001) were associated with loss of primary patency and increased MALE. High center volume (>5 procedures/year) was associated with improved primary patency (p=0.015), and lower MALE (p=0.021) at 2 years. CONCLUSIONS: Despite decreased utilization, open surgical bypass to distal targets at the ankle remains a viable option for treatment of IP-CLTI with acceptable patency and amputation-free survival rates at 2 years. Bypasses to distal targets should be performed at high volume centers to optimize graft patency and limb salvage and minimize re-interventions.

Aortobifemoral bypass vs covered endovascular reconstruction of aortic bifurcation.

BACKGROUND: Covered endovascular reconstruction of aortic bifurcation (CERAB) is increasingly used as a first line-treatment in patients with aortoiliac occlusive disease (AIOD). We sought to compare the outcomes of patients who underwent CERAB compared with the gold standard of aortobifemoral bypass (ABF). METHODS: The Vascular Quality Initiative was queried for patients who underwent ABF or CERAB from 2009 to 2021. Propensity scores were generated using demographics, comorbidities, Rutherford class, and urgency. The two groups were matched using 5-to-1 nearest-neighbor match. Our primary outcomes were 1-year estimates of primary patency, major adverse limb events (MALEs), MALE-free survival, reintervention-free survival, and amputation-free survival. Standard statistical methods were used. RESULTS: A total of 3944 ABF and 281 CERAB cases were identified. Of all patients with AIOD, the proportion of CERAB increased from 0% to 17.9% between 2009 and 2021. Compared with ABF, patients who underwent CERAB were more likely to be older (64.7 vs 60.2; P < .001) and more often had diabetes (40.9% vs 24.1%; P < .001) and end-stage renal disease (1.1% vs 0.3%; P = .03). In the matched analysis (229 CERAB vs 929 ABF), ABF patients had improved MALE-free survival (93.2% [±0.9%] vs 83.2% [±3%]; P < .001) and lower rates of MALE (5.2% [±0.9%] vs 14.1% [±3%]; P < .001), with comparable primary patency rates (98.3% [±0.3%] vs 96.6% [±1%]; P = .6) and amputation-free survival (99.3% [±0.3%] vs 99.4% [±0.6%]; P = .9). Patients in the CERAB group had significantly lower reintervention-free survival (62.5% [±6%] vs 92.9% [±0.9%]; P < .001). Matched analysis also revealed shorter length of stay (1 vs 7 days; P < .001), as well as lower pulmonary (1.2% vs 6.6%; P = .01), renal (1.8% vs 10%; P < .001), and cardiac (1.8% vs 12.8%; P < .001) complications among CERAB patients. CONCLUSIONS: CERAB had lower perioperative morbidity compared with ABF with a similar primary patency 1-year estimates. However, patients who underwent CERAB experienced more major adverse limb events and reinterventions. Although CERAB is an effective treatment for patients with AIOD, further studies are needed to determine the long-term outcomes of CERAB compared with the established durability of ABF and further define the role of CEARB in the treatment of AIOD.

Outcomes of octogenarians receiving aortic repair.

OBJECTIVE: Abdominal aortic aneurysm (AAA) repair is recommended for aneurysms greater than 5.5 cm in men and 5 cm in women. Because AAA is more common among the elderly, we sought to evaluate contemporary practices of elective AAA repair and 2-year postoperative outcomes in octogenarians. METHODS: We identified octogenarians undergoing elective AAA repair in the Vascular Quality Initiative from 2012 to 2019. We included patients undergoing endovascular (EVAR) and open (OAR) aortic repair. Demographics and comorbid conditions were compared between patient groups. Frailty was calculated using previously published methods. Patients with frailty scores above the 75th percentile of the operative cohort were considered high frailty. The primary outcome was 1- and 2-year mortality. Secondary outcomes included postoperative complications. Standard statistical methods were utilized. Cox proportional hazard models were used to identify factors that affect mortality. RESULTS: The frequency of AAA repair in octogenarians has remained stable. Of all aortic operations, 21.4% were performed on octogenarians; 9735 (23.3% of 41,712) EVAR and 755 (10.3% of 7325) OARs. Among octogenarian patients, 42.0% of EVARs were under size thresholds: 48.3% males ≤5.5 cm diameter and 21.5% females ≤5.0 cm diameter compared with 18.8% OARs: 23.4% males and 10.7% females. Additionally, 25.6% had high frailty scores. Among octogenarians, 1- and 2-year mortality was 9.3% ± 0.3% and 14.8% ± 0.4% for EVAR and 15.2% ± 1.3% and 18.9% ± 1.5% for OAR patients, respectively (P < .01). In-hospital mortality rate was higher after OAR (0.87% EVAR vs 7.55% OAR; P < .01) and differed with frailty (EVAR, low frailty 0.2% vs high frailty 1.7%; OAR, low frailty 2.3% vs high frailty 15.6%). For EVAR, patient factors associated with mortality included heart failure (hazard ratio [HR], 1.15; 95% confidence interval [CI], 1.06-1.25; P = .001) and dialysis (HR, 1.71; 95% CI, 1.13-2.59; P = .012). For OAR, coronary artery disease (HR, 1.55; 95% CI, 0.98-2.44; P = .062) was associated with mortality. Statin use was protective of mortality for all patients (EVAR: HR, 0.68; 95% CI, 0.60-0.78; P < .01): OAR: HR, 0.58; 95% CI, 0.37-0.92; P = .020). Among octogenarians, high frailty was independently associated with 2-year mortality (EVAR: HR, 3.36; 95% CI, 2.62-4.31; P < .01 and OAR: HR, 2.35; 95% CI, 1.09-5.10; P = .030). CONCLUSIONS: Nationally, a large portion of elective AAA repair in octogenarians is performed below recommended size thresholds, one-quarter of whom are frail with poor long-term 2-year mortality rates. High 2-year mortality following AAA repair in this age group exceeds the published risk of rupture for 5- to 5.5-cm AAA, suggesting that increase in the size threshold of elective repair among octogenarians should be explored.

Incidence and Outcomes of Visceral Ischemia in Acute Aortic Occlusion.

BACKGROUND: Acute aortic occlusion (AAO) is a morbid diagnosis in which mortality correlates with severity of ischemia on presentation. Visceral ischemia (VI) is challenging to diagnose and its presentation as a consequence of AAO is not well-studied. We aim to identify characteristics associated with VI in AAO to facilitate diagnosis. METHODS: Patients diagnosed with AAO who underwent revascularization were identified retrospectively from institutional records (2006-2020). The primary outcome was the development of VI (intra-abdominal ischemia). Univariate analysis was used to compare demographic, exam, imaging, and intraoperative variables between patients with and without VI in the setting of AAO. RESULTS: Ninety-one patients were included. The prevalence of VI was 20.9%. Preoperative comorbidities, time to revascularization, and operative approach did not differ between patients with and without VI. Patients with VI more frequently were transferred from outside institutions (100% vs. 53%, P = 0.02), presented with advanced acute limb ischemia (Rutherford III 36.9% vs. 7.5%, P < 0.01), and had elevated preoperative serum lactate (4.31 vs. 2.41 mmol/L, P < 0.01). VI patients had an increased occurrence of bilateral internal iliac artery (IIA) occlusion (47.4% vs. 18.1%, P = 0.01). Unilateral IIA occlusion, level of aortic occlusion, and patency of inferior mesenteric arteries were not associated with VI. Patients with VI had worse postoperative outcomes. In particular, VI conferred significant risk of mortality (odds ratio 5.45, P < 0.01). CONCLUSIONS: Visceral ischemia is a common consequence of AAO. Elevated lactate, bilateral IIA occlusion, and advanced acute limb ischemia (ALI) should increase clinical suspicion for concomitant VI with AAO and may facilitate earlier diagnosis to improve outcomes.

Racial Disparities in Treatment Indications and Outcomes for Limb Ischemia.

BACKGROUND: Studies suggest that the Affordable Care Act (ACA) of 2014 has improved access to vascular care and vascular outcomes among patients suffering from peripheral arterial disease (PAD). We sought to examine the racial disparities that exist in patients with PAD who have undergone lower extremity bypass (LEB) or a peripheral vascular intervention (PVI) using the Vascular Quality initiative (VQI) database. METHODS: The VQI infrainguinal and PVI datasets were queried for patients receiving elective and urgent LEB or PVI between 2016, 2 years after ACA implementation, and in 2021. Patients undergoing interventions urgently/emergently or for aneurysm were excluded. The primary outcome was major adverse limb event (MALE-defined as any vascular reintervention or above-ankle amputation) free survival at 1 year. Standard statistical methods were utilized as appropriate. RESULTS: A total of 17,455 LEB and 87,475 PVIs were included in this analysis. Black persons present at a younger age when compared to non-Hispanic White persons (NHW) and are more likely to have diabetes, hypertension, end-stage renal disease (ESRD), and higher rates of prior amputation. Black persons are more likely to present with chronic limb-threatening ischemia (CLTI) rather than claudication, and in a more urgent setting. Postoperative outcomes show higher rates of major amputations among racial minorities, specifically Black persons for both LEB (1.8% vs. 0.8% P < 0.001) and PVI (20.8% vs. 16.8% P < 0.001). Black persons are at higher risk of 1-year MALE for LEB (36.7% vs. 29.9% P < 0.001) and PVI (31.0% vs. 21.7%; P < 0.001). Even after adjusting for confounding variables, Black persons have a higher risk of 1-year MALE for LEB, with an adjusted hazard ratio (aHR) of 1.15 (95% CI [1.05-1.26], P = 0.003) and PVI (aHR 1.18 95% CI [1.12-1.24], P < 0.001). Other major determinates of 1-year MALE on multivariate Cox regression included CLTI (LEB aHR 1.57 95% CI [1.43-1.72], P < 0.001; PVI aHR 2.29 95% CI [2.20-2.39], P < 0.001) and history of prior amputation (LEB aHR 1.35 95% CI [1.17-1.56], P < 0.001; PVI aHR 1.5 95% CI [1.4-1.6], P < 0.001). CONCLUSIONS: Compared to NHW persons, Black persons present with more advanced vascular disease regardless of the operative indication. Black persons are also at significantly higher risk of 1-year MALE. Despite some advances in more accessible care through the ACA of 2014, our observations suggest that Black persons still have significantly worse outcomes due to variety of variables that need further investigation.

Trends in mortality and postoperative complications among octogenarian patients undergoing carotid endarterectomy.

BACKGROUND: Elderly patients represent a large portion of patients undergoing vascular surgery. This study aims to assess the contemporary frequency of octogenarians undergoing carotid endarterectomy (CEA) and to evaluate their postoperative complications and survival rates. METHODS: The Vascular Quality Initiative (VQI) dataset was queried for patients who underwent elective CEA between 2012 and 2021. Patients aged >90 years were excluded, as well as emergent and combined cases. The population was divided into two age groups: <80 years and ≥80 years. Frailty scores were generated using Vascular Quality Initiative variables grouped into 11 domains historically associated with frailty. Patients with scores within the first 25th percentile, between the 25th and 50th percentile, and above the 75th percentile were categorized into low, medium, and high frailty classes, respectively. Procedural indications were defined as hard (stenosis ≥80% or ipsilateral neurologic symptoms) or soft. Primary outcomes of interest were 2-year stroke-free and 2-year overall survival comparing (i) octogenarians with nonoctogenarians and (ii) octogenarians by frailty class. Standard statistical methods were used. RESULTS: Overall, 83,745 cases were included in this analysis. Between 2012 and 2021, a consistent proportion averaging 17% of CEA patients were octogenarians. Among this age group, the proportion of patients undergoing CEA for hard indications increased over time from 43.7% to 63.8% (P < .001). This increase was accompanied by a statistically significant increase in the combined 30-day perioperative stroke and mortality rate from 1.56% in 2012 to 2.96% in 2021 (P = .019). A Kaplan-Meier analysis showed a significantly lower 2-year stroke-free survival among octogenarians compared with the younger group (78.1% vs 87.6%; P < .001). Similarly, there was a significantly lower 2-year overall survival among octogenarians compared with the younger group (90.5% vs 95.1%; P < .001). Multivariate Cox proportional hazard analyses showed that high frailty class was associated with increased 2-year stroke risk (hazard ratio, 2.26; 95% confidence interval, 1.61-3.17; P < .001) and 2-year mortality (hazard ratio, 2.43; 95% confidence interval, 1.71-3.47; P < .001). Repeat Kaplan-Meier analysis stratifying octogenarians by frailty class revealed that octogenarians with low frailty can have stroke-free and overall survival rates comparable with nonoctogenarians (88.2% vs 87.6% [P = .158] and 96.0% vs 95.1% [P = .151], respectively). CONCLUSIONS: Chronological age should not be regarded as a contraindication for CEA. Frailty score calculation is a better predictor for postoperative outcomes and is an appropriate tool to risk stratify octogenarians, aiding in the decision between best medical treatment or intervention. The risk benefit assessment for high frailty class octogenarians is paramount because the postoperative risks may outweigh the long-term survival benefits of the prophylactic CEA.

Outcomes of operative and nonoperative management of blunt thoracic aortic injury.

OBJECTIVE: Although the current guidelines for the management of blunt traumatic aortic injury (BTAI) have recommended intervention for grade 2 injuries or higher, a national trend has occurred for aggressive endovascular treatment of low-grade BTAIs. Little is known about the natural history of grade 1 and 2 injuries treated nonoperatively. We hypothesized that most of these low-grade injuries would remain stable with nonoperative management. METHODS: We performed a review of BTAIs at a large referral level 1 trauma center from 2004 to 2020. The injuries were graded using a standard 1 to 4 scale. The outcomes of the nonoperative and thoracic endovascular aortic repair (TEVAR) management strategies were compared, including post-trauma morbidity, mortality, reinterventions, and lesion stability. RESULTS: A total of 176 patients with BTAIs and sufficient imaging studies and follow-up data available were identified during the study period, including 36 with grade 1, 24 with grade 2, 115 with grade 3, and 1 with a grade 4 injury. Of these 176 patients, 112 had undergone TEVAR and 64 had been treated nonoperatively. Most of the patients (90.2%) who had undergone TEVAR had had grade 3 injuries. Nonoperative management was performed for 97.2% of the grade 1 injuries and 62.5% of the grade 2 injuries. Endovascular reintervention after TEVAR was rare (2.7%). The rates of post-trauma morbidity within 30 days (stroke, 3.6% vs 3.1%; myocardial infarction/arrhythmia, 8.9% vs 1.6%; respiratory failure, 31.2% vs 28.1%; acute kidney injury, 9.8% vs 12.5%; urinary tract infection, 2.7% vs 4.8%; gastrointestinal bleeding, 3.6% vs 0.0%; pulmonary embolism, 10.9% vs 4.5%) and 1-year mortality after discharge (1.8% vs 3.1%) were comparable between the operative and nonoperative groups. The median follow-up was 1501 days (interquartile range [IQR], 475.6-2804 days) for the TEVAR group and 1170.5 days (IQR, 317-2173 days) for the nonoperative group. No lesion progression had occurred in the patients with low-grade (grade 1-2) injuries managed nonoperatively. Resolution of grade 1 and 2 injury had occurred in 20% of the patients at 30 days, which had improved to 44% at long-term follow-up. Fourteen patients with grade 3 injuries (12.2% of the grade 3 injuries in our series) were also observed and did not require future intervention. These patients had generally had smaller pseudoaneurysms with minimal periaortic hematoma. None of these 14 patients had experienced progression or rupture during follow-up (median, 454.5 days; IQR, 81-1199 days) using computed tomography. CONCLUSIONS: Nonoperative management of low-grade BTAIs did not result in long-term aortic complications or the need for reintervention. We found that grade 3 injuries with smaller pseudoaneurysms and minimal periaortic hematoma can be safely observed if the patients can be appropriately followed up. Thus, the indications for treatment of select grade 3 injuries merit further consideration.

Contemporary management of acute and chronic mesenteric ischemia: 10-year experience from a multihospital healthcare system.

OBJECTIVE: Endovascular and hybrid methods have been increasingly used to treat mesenteric ischemia. However, the long-term outcomes and risk of symptom recurrence remain unknown. The objective of the present study was to define the predictors of postoperative morbidity, mortality, and patency loss for acute mesenteric ischemia (AMI) and chronic mesenteric ischemia (CMI). METHODS: The inpatient and follow-up records for all patients who had undergone revascularization for AMI and CMI from 2010 to 2020 at a multicenter hospital system were reviewed. Patency and mortality were evaluated with Cox regression, visualized with Kaplan-Meier curves, and compared using log-rank testing. Patency was further evaluated using Fine-Gray regression with death as a competing risk. The postoperative major adverse events (MAE) and 30-day mortality were evaluated with logistic regression. RESULTS: A total of 407 patients were included, 148 with AMI and 259 with CMI. For the AMI group, the 30-day mortality was 31%. Open surgery was associated with lower rates of bowel resection (odds ratio [OR], 0.23; 95% confidence interval [CI], 0.13-0.61). The etiology of AMI also did not change the outcomes (OR, 1.30; 95% CI, 0.77-2.19). Adjusted analyses indicated that a history of diabetes (OR, 2.77; 95% CI, 1.37-5.61) and sepsis on presentation (OR, 2.32; 95% CI, 1.18-4.58) were independently associated with an increased risk of 30-day MAE. In the CMI group, open surgery and chronic kidney disease were associated with a higher incidence of MAE (OR, 3.03; 95% CI, 1.14-8.05; OR, 2.37; 95% CI, 1.31-4.31). In contrast, chronic kidney disease (OR, 3.02; 95% CI, 1.10-8.37) and inpatient status before revascularization (OR, 2.78; 95% CI, 1.01-7.61) were associated with increased 30-day mortality. For the CMI group, the endovascular cohort had experienced greater rates of symptom recurrence (29% vs 13%) with a faster onset (endovascular, 64 days; vs bypass, 338 days). CONCLUSIONS: AMI remains a morbid disease despite the evolving revascularization techniques. An open approach should remain the reference standard because it reduces the likelihood of bowel resection. For CMI, endovascular interventions have improved the postoperative morbidity but have also resulted in early symptom recurrence and reintervention. An endovascular-first approach should be the standard of care for CMI with close surveillance.

Open Surgical Secondary Interventions are More Durable than Endovascular Interventions for Lower Extremity Bypass Stenosis or Occlusion.

Objectives: Lower extremity bypasses often require secondary interventions to maintain patency. Our objectives were to characterize effectiveness of secondary interventions to maintain or restore bypass graft patency, and to compare outcomes of open and endovascular interventions. Methods: We reviewed patients who underwent lower extremity bypass at our institution from 2007 to 2010. We recorded the index bypass and subsequent ipsilateral interventions performed through 2018 or until loss of secondary patency. Patient, procedure, and anatomic data were collected. Endovascular intervention was compared with open/hybrid intervention. For outcome analysis, patency measures were defined relative to the time of the secondary intervention rather than the time of the index bypass. Results: 174 secondary interventions (56 open/hybrid, 118 endovascular; 42 for graft occlusion, and 132 for stenosis) treating 228 lesions in 97 bypasses were available for study. The index bypass was most commonly performed for tissue loss (71.1%), utilized a tibial artery target (57.7%), and used single-segment great saphenous vein (59.8%) rather than alternative vein (32.0%) or prosthetic (8.2%). A higher portion of open/hybrid interventions (51.8%) were done for graft occlusion than endovascular interventions (11.0%, P < .001). Mean follow-up for secondary interventions was 3.5 years. A multivariate Cox proportional hazards model identified female gender, prior MI, anticoagulation, occlusion, and endovascular intervention as predictors of loss of primary patency. Intervention for occlusion predicted poorer primary and secondary patency. Endovascular intervention was associated with poorer primary patency as compared to open intervention and a trend toward poorer secondary patency. Conclusions: Both open and endovascular secondary interventions on lower extremity bypasses are low-risk procedures that offer acceptable patency. Although more commonly performed in the setting of graft occlusion, open surgical interventions show improved durability compared to endovascular interventions. Some patients, including those with occluded grafts, may benefit from more liberal use of open surgical intervention to restore bypass patency.

Younger patients have worse outcomes after peripheral endovascular interventions for suprainguinal arterial occlusive disease.

OBJECTIVE: The choice of intervention for treating suprainguinal arterial disease, open bypass vs endovascular intervention, is often tempered by patient age and comorbidities. In the present study, we compared the association of patient age with 1-year major adverse limb events (MALE)-free survival and reintervention-free survival (RFS) rates among patients undergoing intervention for suprainguinal arterial disease. METHODS: The Vascular Quality Initiative datasets for bypass and peripheral endovascular intervention (PVI; aorta and iliac only) were queried from 2010 to 2017. The patients were divided into two age groups: <60 and ≥60 years at the procedure. Age-stratified propensity matching of patients in bypass and endovascular procedure groups by demographic characteristics, comorbidities, and disease severity was used to identify the analysis samples. The 1-year MALE-free survival and RFS rates were compared using the log-rank test and Kaplan-Meier plots. Proportional hazard Cox regression was used to perform propensity score-adjusted comparisons of MALE-free survival and RFS. RESULTS: A total of 14,301 cases from the Vascular Quality Initiative datasets were included in the present study. Propensity matching led to 3062 cases in the ≥60-year group (1021 bypass; 2041 PVI) and 2548 cases in the <60-year group (1697 bypass; 851 PVI). In the crude comparison of the matched samples, the older patients undergoing bypass had had significantly greater in-hospital (4.6% vs 0.9%; P < .001) and 1-year (10.5% vs 7.5%; P = .005) mortality compared with those who had undergone endovascular intervention. The rates of MALE (7.5% vs 14.3%; P < .001) and reintervention (6.7% vs 12.7%; P < .001) or death were significantly higher for the younger group undergoing PVI than bypass at 1 year. However, the rates of MALE (12.9% vs 14.3%; P = .298) and reintervention (12.7% vs 12.9%; P = .881) or death for were similar both procedures for the older group. Both log-rank analyses and the adjusted propensity score analyses of MALE-free survival and RFS in the two age groups confirmed these findings. The adjusted comparison of outcomes using propensity score matching favored PVI at 1-year survival (hazard ratio, 1.4; 95% confidence interval, 1.1-1.9; P = .003) for the older group but was not different for the younger group (hazard ratio, 0.6; 95% confidence interval, 0.3-1.0; P = .054). CONCLUSIONS: Among the patients aged <60 years undergoing intervention for suprainguinal arterial disease, the choice of therapy should be open surgical intervention given the higher risk of reintervention and MALE with endovascular intervention. Endovascular intervention should be favored for patients aged ≥60 years because of reduced perioperative mortality.

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.

Nationwide trends in drug-coated balloon and drug-eluting stent utilization in the femoropopliteal arteries.

OBJECTIVE: Drug-coated balloons (DCB) and drug-eluting stents (DES) have significantly altered treatment paradigms for femoropopliteal lesions. We aimed to describe changes in practice patterns as a result of the infusion of these technologies into the treatment of peripheral arterial disease. METHODS: We queried the Vascular Quality Initiative registry from 2010 to 2017 for all peripheral vascular interventions involving the superficial femoral artery and/or the popliteal artery. Cases were divided into a PRE and a POST era with a cutoff of September 2016, when specific device identity was first recorded in Vascular Quality Initiative. For each artery, a primary treatment was identified as either plain balloon angioplasty, atherectomy, DCB, bare-metal stent, or DES. The relative distribution of primary treatments between the PRE and POST eras was evaluated, as were lesion characteristics associated with DCB and DES use and regional variability in the adoption of these new technologies. RESULTS: Of 210,666 arteries in the dataset, 91,864 femoropopliteal arteries (across 74,842 procedures in 55,437 patients) were included. Each artery received 1.5 ± 0.6 treatments. Primary treatment use changed from 40% balloon angioplasty, 45% stenting, and 15% atherectomy in the PRE era to 22% plain balloon angioplasty, 26% bare-metal stent, 8% atherectomy, 37% DCB, and 8% DES in the POST era (P < .001). Forty-three percent of arteries received a drug-containing device as a primary or adjunctive therapy and 1.3% received both a DCB and DES in the POST era. DCB use as the primary treatment was highest in lesions with length 10.0 to 19.9 cm (42%), TransAtlantic InterSociety A, B, or C lesions (38%), and lesions with mild to no calcification (38%). DES use was highest in lesions with a length of 20 cm or more (12%), TransAtlantic InterSociety D lesions (13%), and lesions with moderate to severe calcification (9%). The range of use across 18 regions was 125 to 40% for DCB and 1% to 14% for DES. Regional variability was greater for DES (SD 4% vs mean 8%) than for DCB (SD 7% vs mean 29%). CONCLUSIONS: There has been a rapid dissemination of DCB and DES technology in the femoropopliteal vessels, with nearly one-half of arteries receiving a drug-containing therapy in modern practice. DCBs are most used in medium length, minimally calcified lesions and DESs are most used in longer, more heavily calcified lesions. There is significant regional variability in adoption, especially with DES.

CT Three-Dimensional (3D) Modeling Maintains Fluoroscopy Time and Contrast Volume to a Minimum in the Endovascular Treatment of Great Vessel Injury from Iatrogenic Trauma.

CT angiography with multislice detector has become the preferred method for assessment of hemodynamically stable patients suspected of great vessel injury from iatrogenic and blunt trauma. The CT images obtained can be transformed into a three-dimensional (3D) model using the software within minutes. This allows the clinician to evaluate the injury and the injury's proximity to other vital structures for operative planning. The 3D modeling provides geometric calibration of the c-arm or image intensifier in regard to optimal cranial/caudal and oblique angles to evaluate and treat the vessel injury. We describe a case of a 28-year-old female undergoing a cesarian section and hysterectomy for placenta percreta, who sustained a right subclavian artery injury (presumed wire injury) from inadvertent right common carotid artery cannulation during placement of a right internal jugular 8 French resuscitative central line. A 3D model was created from the CT angiography to locate the small pseudoaneurysm of the right subclavian artery. The optimal projection was obtained using the 3D reconstructive software to visualize the injury and its relation to the right vertebral artery ostium for endovascular planning. This preoperative maneuver allowed for limited radiation exposure and contrast volume used to treat the injury.

Lemierre's Syndrome: An Atypical Presentation.

Septic thrombophlebitis is a rare diagnosis in this era of widespread antibiotic usage. The clinical diagnosis requires astute clinical suspicion and evaluation. We describe an asplenic 63-year-old woman who presented to the emergency department with a 24-hour history of a tender, swollen, right neck and upper chest wall. She denied any recent illnesses, but two years before, she was hospitalized and treated for Streptococcus pneumoniae meningitis and endocarditis. An enhanced computed tomography scan demonstrated inflammatory changes around a thrombosed right internal jugular vein, which extended to the brachiocephalic/superior vena cava junction. A retropharyngeal effusion was present, but no pulmonary or oropharyngeal abscess was identified. Lemierre's syndrome, although rare, must be recognized promptly to reduce morbidity and mortality associated with this condition.

Occult type I or III endoleaks are a common cause of failure of type II endoleak treatment after endovascular aortic repair.

OBJECTIVE: Most type II endoleaks have a benign natural history, but 6% to 8% are associated with sac enlargement and respond poorly to treatment. Our aim was to evaluate whether these enlargements are associated with delayed or occult type I and III endoleaks. METHODS: Patients with interventions for endoleak after endovascular aortic repair from 2000 to 2016 were reviewed retrospectively. Patient demographics, comorbidities, endoleak type, secondary procedures, aortic sac growth (≥5 mm), and mortality were collected. Successful treatment was defined as endoleak resolution with no further aortic sac growth. Secondary procedures, ruptures, endograft explant, and death were captured. RESULTS: There were 130 patients diagnosed with a primary type II endoleak after endovascular aortic repair at a median of 1.3 months (interquartile range, 1.0-13.3 months). One hundred eighteen had their initial treatment for a primary type II. Twelve of the 130 were initially stable and observed, but were treated for a delayed type I or III endoleak. The 130 patients underwent 279 procedures for endoleaks (mean of 2.2 ± 1.3) over 6.9 ± 3.8 years of follow-up. Of the 118 patients treated for primary type II endoleaks, 26 (22.0%) later required interventions for delayed type I and III endoleaks. The mean time to intervention for a delayed type I or III endoleak was 5.4 ± 2.8 years. Overall, there were 16 type IA, 11 type IB, 2 type III, 7 combined type IA/IB, and 2 type IA/III delayed endoleaks. The odds of harboring a delayed type I or III endoleak was 22.0% before the first attempt at type II endoleak treatment, 35.1% before the second, 44.8% before the third, and 66.6% before the fourth attempts. Rapid aortic sac growth of ≥5 mm/y before initial endoleak treatment was associated with increased risk for delayed type I or III endoleak (47.8 vs 14.1%; P = .003). Patients with delayed type I or III endoleaks had a lower successful treatment rate (8.3% vs 52.3%; P = .001) than those with only type II endoleaks. Late rupture was increased with delayed type I or III endoleak (P = .002), whereas mortality (P = .96) and aortic-related mortality (P = .46) were similar. Graft explant (P = .06) trended toward an increase with a delayed type I or III endoleak, but was not statistically significant. CONCLUSIONS: Failed attempts treating type II endoleaks and/or a rapid aortic sac growth of 5 mm/y or greater should raise the suspicion of a delayed or occult type I or III endoleak. Occult endoleaks are associated with decreased chance of endoleak resolution.

Increasing use of open conversion for late complications after endovascular aortic aneurysm repair.

OBJECTIVE: Open procedures are often required for late complications after endovascular aneurysm repair (EVAR). Our aim was to describe the indications for open interventions and their postoperative outcomes and to specifically examine our experience with limited conversions in which problem endoleaks are targeted without endograft explantation. METHODS: We reviewed patients from 2002 to 2017 who underwent any surgical abdominal aortic operation after a previous EVAR. Baseline characteristics, preoperative imaging, procedural details, and postoperative outcomes were reviewed. The primary end point was 30-day mortality. RESULTS: There were 102 patients who underwent open conversion 3.8 ± 3.1 years after EVAR. The numbers increased significantly in recent years, with 18 cases performed in 2016; 48.5% of patients had undergone 1.9 ± 1.0 prior endovascular interventions. The indication for surgical conversion was an endoleak in 85 patients and infection in 15. One patient had a limb occlusion and another a proximal aneurysm. The 30-day mortality was 6.2% in 65 patients treated electively for endoleak but higher in 20 ruptures (40.0%) and 15 infections (40.0%). In a multivariate logistic regression model, independent predictors of 30-day mortality were rupture (odds ratio [OR], 6.70; 95% confidence interval [CI], 1.75-25.60; P = .005), endograft infection (OR, 8.48; 95% CI, 1.99-36.20; P = .004), and use of a supraceliac clamp (OR, 4.80; 95% CI, 1.47-15.66; P = .009). Transient acute kidney injury (12.8%) and prolonged intubation (11.8%) were the most common postoperative complications. In 65 patients treated for endoleak without rupture, 37 underwent endograft explantation, whereas 28 had a graft-preserving intervention (branch vessel ligation for type II endoleak in 26, external banding of the aneurysm neck for type IA endoleak in 8). Mortality was 8.1% when the endograft was explanted and 3.6% when it was not (P = .63). During 3.0 ± 3.5 years of follow-up, there was one reintervention after endograft explantation (for rupture secondary to type IB endoleak) and two reinterventions after graft preservation (for a new type IA endoleak and a new type II endoleak). Survival was 87.4% at 1 year and 70.9% at 5 years. CONCLUSIONS: Open conversion is playing an increasing role in the management of late EVAR complications. Endoleaks treated electively by open conversion are reasonably safe and show good midterm durability, even with graft-preserving interventions that avoid endograft explantation.

P2Y2 nucleotide receptor mediates arteriogenesis in a murine model of hind limb ischemia.

OBJECTIVE: Arteriogenesis represents the maturation of preformed vascular connections in response to flow changes and shear stress. These collateral vessels can restore up to 60% of the native blood flow. Shear stress and vascular injury can induce the release of nucleotides from vascular smooth muscle cells and platelets that can serve as signaling ligands, suggesting they may be involved in mediating arteriogenesis. The P2Y2 nucleotide receptor (P2Y2R) has also been shown to mediate smooth muscle migration and arterial remodeling. Thus, we hypothesize that P2Y2R mediates arteriogenesis in response to ischemia. METHODS: Hind limb ischemia was induced by femoral artery ligation (FAL) in C57Bl/6NJ or P2Y2R negative mice (P2Y2(-/-)). Hind limb perfusion was measured with laser Doppler perfusion imaging and compared with the sham-operated contralateral limb immediately and at 3, 7, 14, 21, and 28 days after ligation. Collateral vessel size was measured by Microfil casting. Muscle specimens were harvested and analyzed with immunohistochemistry for Ki67, vascular cell adhesion molecule, macrophages, and muscle viability by hematoxylin and essoin stain. RESULTS: Hind limb ischemia induced by FAL in C57Bl/6NJ mice resulted in significant ischemia as measured by laser Doppler perfusion imaging. There was rapid recovery to nearly normal levels of perfusion by 2 weeks. FAL in P2Y2(-/-) mice resulted in severe ischemia with greater tissue loss. Recovery of perfusion was impaired, achieving only 40% compared with wild-type mice by 28 days. Collateral vessels in the P2Y2(-/-) mice were underdeveloped, with reduced vascular cell proliferation and smaller vessel size. The collaterals were ∼65% the size of wild-type collateral vessels (P = .011). Angiogenesis at 28 days in the ischemic muscle, however, was greater in the P2Y2(-/-) mice (P < .001), possibly related to persistent ischemia leading and angiogenic drive. Early macrophage recruitment was reduced by nearly 70% in P2Y2(-/-) despite significantly more myocyte necrosis. However, inflammation was greater at 28 days in the P2Y2(-/-) mice. CONCLUSIONS: P2Y2R deficiency does not alter baseline collateral vessel formation but does significantly impair collateral maturation, with resultant persistent limb ischemia despite enhanced angiogenesis. These findings reinforce the importance of arteriogenesis in the recovery of perfusion in ischemic tissues compared with angiogenesis. They also support the role of P2Y2R in mediating this process. The mechanism by which P2Y2R mediates arteriogenesis may involve the recruitment of inflammatory cells to the ischemic tissues, which is essential to arteriogenesis. Approaches to target P2Y2R may yield new therapeutic strategies for the treatment of arterial occlusive disease.

Xanthine Oxidoreductase Function Contributes to Normal Wound Healing.

Chronic, nonhealing wounds result in patient morbidity and disability. Reactive oxygen species (ROS) and nitric oxide (NO) are both required for normal wound repair, and derangements of these result in impaired healing. Xanthine oxidoreductase (XOR) has the unique capacity to produce both ROS and NO. We hypothesize that XOR contributes to normal wound healing. Cutaneous wounds were created in C57Bl6 mice. XOR was inhibited with dietary tungsten or allopurinol. Topical hydrogen peroxide (H2O2, 0.15%) or allopurinol (30 µg) was applied to wounds every other day. Wounds were monitored until closure or collected at d 5 to assess XOR expression and activity, cell proliferation and histology. The effects of XOR, nitrite, H2O2 and allopurinol on keratinocyte cell (KC) and endothelial cell (EC) behavior were assessed. We identified XOR expression and activity in the skin and wound edges as well as granulation tissue. Cultured human KCs also expressed XOR. Tungsten significantly inhibited XOR activity and impaired healing with reduced ROS production with reduced angiogenesis and KC proliferation. The expression and activity of other tungsten-sensitive enzymes were minimal in the wound tissues. Oral allopurinol did not reduce XOR activity or alter wound healing but topical allopurinol significantly reduced XOR activity and delayed healing. Topical H2O2 restored wound healing in tungsten-fed mice. In vitro, nitrite and H2O2 both stimulated KC and EC proliferation and EC migration. These studies demonstrate for the first time that XOR is abundant in wounds and participates in normal wound healing through effects on ROS production.

Secondary abdominal compartment syndrome after severe extremity injury: are early, aggressive fluid resuscitation strategies to blame?

INTRODUCTION: Secondary abdominal compartment syndrome (ACS) is the development of ACS in the absence of abdominal injury. The development of secondary ACS has been viewed by some authors as an unavoidable sequela of the aggressive crystalloid resuscitation often employed in the treatment of severe shock. We hypothesized that poor resuscitation techniques, including early and excessive crystalloid administration, places patients with extremity injuries at risk for developing secondary ACS. METHODS: The Trauma Registry of the American College of Surgeons database was queried for all patients with an extremity Abbreviated Injury Scale (AIS) score of 3 or greater and abdominal AIS score of 0 treated at our institution between January 1, 2001 and December 31, 2005. The study group included those patients who developed secondary ACS, whereas the comparison cohort included those who did not develop secondary ACS. RESULTS: Forty-eight patients developed secondary ACS and were compared with 48 randomly selected patients who had an extremity AIS score of 3 or greater and an abdomen AIS score of 0. There were no differences between the groups with respect to age, sex, race, or individual AIS scores. However, the secondary ACS group had a slightly higher Injury Severity Score (25.6 vs. 21.4, p = 0.02), significantly higher operating room crystalloid administration (9.9 L vs. 2.7 L, p < 0.001), and more frequent use of a rapid infuser (12.5% vs. 0.0%, p = 0.01). Multiple logistic regression identified prehospital and emergency department crystalloid as predictors of secondary ACS. CONCLUSIONS: Aggressive resuscitation techniques, often begun in the prehospital setting, appear to increase the likelihood of patients with severe extremity injuries developing secondary ACS. Early, large volume crystalloid administration was the greatest predictor of secondary ACS.