Association Between Diagnosis-to-Limb Revascularization Time and Clinical Outcomes in Outpatients With Chronic Limb-Threatening Ischemia: Insights From the CLIPPER Cohort.

BACKGROUND: The extent and consequences of ischemia in patients with chronic limb-threatening ischemia (CLTI) may change rapidly, and delays from diagnosis to revascularization may worsen outcomes. We sought to describe the association between time from diagnosis to endovascular lower extremity revascularization (diagnosis-to-limb revascularization [D2L] time) and clinical outcomes in outpatients with CLTI. METHODS AND RESULTS: In the CLIPPER cohort, comprising patients between 66 and 86 years old diagnosed with CLTI betweeen 2010 and 2019, we used Medicare claims data to identify patients who underwent outpatient endovascular revascularization within 180 days of diagnosis. We described the risk-adjusted association between D2L time and clinical outcomes. Among 1 130 065 patients aged between 66 and 86 years with CLTI, 99 221 (8.8%) underwent outpatient endovascular lower extremity revascularization within 180 days of their CLTI diagnosis. Among patients with D2L time <30 days, there was no association between D2L time and all-cause death or major lower extremity amputation. However, among patients with D2L time >30 days, each additional 10-day increase in D2L time was associated with a 2.5% greater risk of major amputation (hazard ratio, 1.025 [95% CI, 1.014-1.036]). There was no association between D2L time and all-cause death. CONCLUSIONS: A delay of >30 days from CLTI diagnosis to lower extremity endovascular revascularization was associated with an increased risk of major lower extremity amputation among patients undergoing outpatient endovascular revascularization. Improving systems of care to reduce D2L time could reduce amputations.

Adjunctive Utilization of Intravascular Ultrasound in Peripheral Arterial Disease Treatment.

BACKGROUND: The utility and benefit of intravascular ultrasound (IVUS) has been well established in coronary interventions, however widespread adoption for peripheral interventions has lagged. The objectives of this review article were to discuss the technical components of IVUS, describe key learning pearls for IVUS utilization, and review the literature describing the clinical outcomes of endovascular peripheral arterial interventions using IVUS. METHODS: A scoping review of the current literature utilizing Pubmed. Terms used to search the literature included "intravascular ultrasound (IVUS)" in conjunction with "peripheral arterial disease (PAD)," "endovascular interventions," "chronic limb threatening ischemia," "balloon angioplasty" "stenting," "percutaneous coronary intervention," and "outcomes." All types of articles were reviewed including review articles, retrospective reviews, meta-analyses, and prospective observational and randomized studies. RESULTS: Published literature regarding IVUS use in peripheral arterial interventions is heterogeneous and limited to mainly retrospective studies, registry analyses and metanalyses. Outcomes are generally favorable with the adjunct of IVUS compared to traditional angiography-driven peripheral interventions. The addition of IVUS improves stent expansion, stent patency, and reduces reintervention rates, particularly in infrainguinal arterial lesions. Long-term costs may also be lower with IVUS-guided procedures. CONCLUSIONS: Expert consensus largely supports the implementation of IVUS in endovascular interventions for peripheral arterial disease. However, more robust high-quality data evaluating the efficacy, durability, and cost of IVUS in peripheral arterial disease are still needed.

Hostile neck anatomy contributes to higher rates of reintervention following endovascular aortic repair for ruptured infrarenal abdominal aortic aneurysm.

INTRODUCTION: Ruptured abdominal aortic aneurysms (AAA) presenting with hostile neck anatomy can represent a challenge in surgical decision-making. We hypothesized that, patients who require reinterventions have higher rates of compromised neck anatomy at initial presentation and may indicate a need for altered surveillance paradigm. METHODS: Patients presenting with ruptured AAA to a single tertiary care institution from 2014 to 2021 were retrospectively reviewed. Those treated with infrarenal EVAR, with no prior aortic surgeries, and with available pre-operative computed tomography (CT) scans were included. Demographics, timing and type of reintervention, follow-up, and survival were collected. CT scans were assessed for hostile neck anatomy via measurements of diameter, length, angle, taper, bulge, calcification, and thrombus. Demographics, comorbidities, and neck anatomy of those with and without reintervention were compared using Fischer's Exact and Student's T-test. Survival was analyzed via Kaplan-Meier and log-rank test. RESULTS: Eighty-nine patients were available for analysis, 37 of which met inclusion criteria. Intraoperative death occurred in 3 patients (8.1%) and 1 patient (2.7%) was intraoperatively converted to an open repair. Thirty-day and 1-year survival were 97% and 91%, respectively. The reintervention rate was 30% (n = 10), occurring at a median of 200 days (18-2053 days) after the index operation. All patients requiring reintervention met hostile neck criteria (p = .002) and had a statistically higher number of hostile neck criteria (1.80 vs 0.87, p = .03). Thirty percent (n = 3) of patients that received a reintervention had neck diameter greater than 3 cm, compared to zero patients in the non-reintervention group (p = .022). Proximal reinterventions (n = 5) had statistically higher neck diameters and neck angle compared to the non-reintervention group. CONCLUSION: Infrarenal rEVAR is effective at preventing acute mortality despite specific anatomic considerations that may contribute to the higher reintervention rates, and therefore those parameters ought to be considered when following patients in the post-intervention period.

A scoping review of female sex-related outcomes after endovascular intervention for lifestyle-limiting claudication and chronic limb-threatening ischemia.

Peripheral arterial disease (PAD) is on the rise, with a growing prevalence in an aging population and increasing rates of diabetes. Chronic limb-threatening ischemia poses a significant risk of limb loss. PAD is common in females, particularly after menopause, with a 35% prevalence rate in females older than 65 years. Studies have suggested that females have inferior outcomes compared with men after endovascular revascularization for PAD. With the rising utilization of endovascular interventions for the treatment of PAD, we sought to perform a review of sex-based outcomes of peripheral endovascular interventions for the treatment of symptomatic PAD. A scoping literature review was conducted to evaluate outcomes in females patients undergoing endovascular peripheral interventions for PAD. Eligibility criteria included studies focusing on adult females with lifestyle-limiting claudication or chronic limb-threatening ischemia who underwent endovascular intervention. Various endovascular procedures were considered and outcomes of interest included mortality, amputations, reinterventions, bleeding complications, and major adverse cardiac events. A systematic search was conducted in PubMed, Embase, Web of Science, and Cochrane Library databases. Sixteen studies were included in the review. Females patients undergoing endovascular interventions were associated with bleeding complications, higher rates of reintervention, and a risk of nonfatal strokes. However, females sex was not linked to higher rates of amputation or conclusively higher mortality rates post intervention. The comprehensive scoping review reveals important sex-related disparities in outcomes after endovascular procedures for symptomatic PAD. Females patients have been reported to experience worse outcomes in terms of reinterventions and bleeding complications. These findings emphasize the need for future trials focusing specifically on females patients to develop sex-inclusive treatment recommendations for advanced PAD.

Ultrasound Examination Without Axial Imaging is Sufficient for Preoperative Planning in Transcarotid Artery Revascularization (TCAR).

BACKGROUND: Duplex ultrasound is frequently used to determine the degree of carotid stenosis. However, axial imaging is typically obtained for operative planning for transcarotid artery revascularization (TCAR). We examined if ultrasound alone is sufficient before TCAR. METHODS: Data from the Vascular Quality Initiative TCAR Surveillance Project registry between 2016 and 2021 was obtained. Patients were divided into 2 groups-those with preoperative ultrasound-alone (US) and those with additional axial imaging (AX). Perioperative outcomes were compared utilizing univariate Chi-square, independent t-test, multivariate logistic regression, and Kaplan-Meier analysis. RESULTS: There were 3,418 patients identified: 682 in the US group and 2,736 in the AX group. More preoperative hypertension was reported in US (16.1% vs. 10.2%, P < 0.001) while cardiovascular disease (23% vs. 28.9%, P = 0.006) and prior ipsilateral stroke (22% vs. 32.7%, P = 0.002) were more prevalent in AX. More patients had history of contralateral carotid endarterectomy (13.6% vs. 16.7%, P = 0.035) or either ipsilateral (2.6% vs. 1.2%, P = 0.002) or contralateral (7.9% vs. 4.9%, P = 0.008) carotid artery stenting in the US group. Lower preoperative creatinine was reported in the US cohort (1.09 ± 0.01 vs. 1.18 ± 0.02, P < 0.001) while more were symptomatic in AX (28.2% vs. 36.2%, P < 0.001). There were no significant differences between lesion characteristics or operative decision making. A slightly higher total procedure time was seen in AX (73.7 ± 0.6 vs. 68.6 ± 1.3 min, P = 0.017). No differences were seen in perioperative transient ischemic attack/stroke or other immediate complications. At 2-year follow-up, both groups reported no significant differences in stroke-free survival (P = 0.750) and independent functional status remained near-identical (97.3% vs. 97.4%, P = 0.921). Kaplan-Meier analysis yielded no significant difference between mortality at 2 years (P = 0.563). Bivariate logistic regression modeling did reveal a statistically significant increase in likelihood of long-term ipsilateral stroke (odds ratio 1.77, P = 0.015) and non stroke-related complication in the postoperative period (odds ratio 4.81, P = 0.005). However, only a statistically significant relationship persisted in non-stroke complication when the model was controlled for between-group differences. CONCLUSIONS: No significant differences in postoperative or long-term complications were noted with additional AX in preoperative TCAR planning. Thus, duplex ultrasound offers a safe and effective alternative for those with contraindication or axial imaging.

Percutaneous, Antegrade Access of the Superficial Femoral Artery can be Safely Used in Procedures for the Treatment of Lower Extremity Limb Ischemia.

BACKGROUND: Recent studies have shown that antegrade access for treatment of infrainguinal peripheral vascular disease is associated with decreased radiation exposure and contrast use without a significant increase in access complication, although data are limited on antegrade superficial femoral artery (SFA) access for larger sheath sizes. We aim to describe a single institution's contemporary experience with percutaneous antegrade SFA access. METHODS: A retrospective review of percutaneous, infrainguinal endovascular interventions for arterial occlusive disease at a major academic institution was conducted between 2018 and 2020. Antegrade, percutaneous, SFA access cases were included. Information on demographics, indication, sheath size, arteries treated, type of intervention, concurrent pedal access, closure devices, and complications was collected and analyzed. RESULTS: A total of 45 patients with an average body mass index of 25.25 were identified. Indications for intervention included tissue loss (64.4%), rest pain (6.7%), claudication (13.3%), and acute limb ischemia (11.1%). Of which, 80.0% of patients had multilevel interventions. Angioplasty was performed in 68.8% of patients, stenting in 8.3%, atherectomy in 15.6%, and thrombectomy in 7.3%. Nearly a quarter of cases involved concurrent pedal access. Maximum sheath size was 4F for 4.4% of patients, 5F for 28.9%, 6F for 46.7%, 7F for 11.1%, and 8F for 8.9%. The closure device was utilized in 75.6% of cases, with no closure device failures. In the entire cohort, there were no demonstrated access site complications. CONCLUSIONS: This study demonstrates percutaneous, antegrade SFA access for complex endovascular interventions for infrainguinal occlusive disease can be effectively utilized, even with larger sheath size. Moreover, routine use of closure devices is safe, improving patient comfort and expediting time to ambulation.

Staging Endovascular Thoracic and Thoracoabdominal Aortic Aneurysm Repairs and the Risk of Post-operative Spinal Cord Ischemia.

OBJECTIVE: Staged aortic aneurysm repair is one method used to decrease the risk of spinal cord ischemia (SCI) following endovascular aortic intervention. Sequential sacrifice of arteries perfusing the spine may allow for improved spinal perfusion through the development of collateral networks over time. To evaluate the impact of staging endovascular aortic aneurysm repairs on SCI, we conducted a conservative analysis of Vascular Quality Initiative (VQI) data. METHODS: De-identified VQI data were queried for cases of endovascular thoracic and thoracoabdominal aneurysm repairs from year 2014 to 2019. Cases were selected based on inclusion criteria: aneurysmal disease, no ruptures, no prior aortic surgeries, no retreatments, and only cases with complete data on aortic zones and SCI. Chi-square, Student's t-tests, and Mann-Whitney U tests were used for univariable analyses, as appropriate. Logistic regression analyses were used to identify independent predictors of outcome. RESULTS: There were 116 staged aortic repairs (SARs) (8.2%) performed out of a total of 1421 endovascular aortic repairs that fit study criteria. The overall rate of SCI within the study cohort was 3.4% (n = 48). The distribution of SARs and SCI events according to aortic zone coverage are displayed in Table 1. Patients who underwent staged endovascular aortic repairs had higher rates of SCI, pre-op spinal drain placement, non-African-American race, COPD, smoking history, positive stress tests, aspirin and statin use, increased estimated blood loss, physician-modified endografts, number of aortic zones covered, lower pre-op hemoglobin levels, larger aneurysm sac size, fusiform aneurysms, and longer total procedure times, Table 2. After adjusting for factors associated with SCI, a priori, and factors with a P < 0.1 univariable analysis, SAR was not associated with SCI (odds ratio [OR] = 1.86, 95% confidence interval [CI] = 0.77-4.50, P = 0.17). Of the six factors associated with SCI on univariable analysis, only procedure time ≥6 hours (OR = 2.49, 95% CI = 1.09-5.70, P = 0.031) and the number of aortic zones covered (OR = 1.15, 95% CI = 1.00-1.32, P = 0.047) were predictive of SCI. Staged repairs had a lower proportion of permanent SCI (38%, 3 of 8 cases) compared with repairs that were not staged (68%, 27 of 40 cases), with a relative risk reduction of 44% for those who developed SCI, P = 0.21. CONCLUSIONS: In a large national data set, SARs were performed for patients with more extensive aortic disease. SARs were only performed in about 8% of cases and the rate of SCI remained low. After adjusting for baseline comorbidities, extent of aortic disease, and other factors that may potentiate SCI, staged aortic aneurysm repair had a similar risk of SCI compared with non-staged repairs. However, there was a trend toward decreased permanent SCI risk in the SAR group.

Contemporary rates of inferior vena cava filter thrombosis and risk factors.

OBJECTIVE: Inferior vena cava (IVC) thrombosis is an uncommon complication associated with IVC filters (IVCFs), with studies reporting rates ranging from 1% to 31%. Few observational studies have described the risk factors associated with IVCF thrombosis, despite the significant clinical sequelae such as post-thrombotic syndrome, venous claudication, and venous ulceration. To better describe IVCF thrombosis and the risk factors, data were queried from Vascular Quality Initiative (VQI) participating centers. METHODS: IVCF data were obtained from the international VQI database from 2013 to 2019. The patients included in the present analysis had 2 years of follow-up data available. The baseline demographics, medical comorbidities, medication, and procedural, anatomic, and postoperative variables were assessed using Kaplan-Meier survival curves with log-rank tests, Student's t tests, or Mann-Whitney U tests for IVCF thrombosis at 2 years. Cox regression analyses were used to identify independent predictors of IVCF thrombosis. A subgroup analysis of those who had presented with venous thromboembolism (VTE) was also performed. RESULTS: A total of 62 U.S. and Canadian VQI-participating centers included 12,874 cases of IVCF placement. Of the 5780 cases with 2 years of follow-up available, 78 (1.3%) had developed IVCF thrombosis. Those who had experienced IVCF thrombosis had had significantly lower rates of diabetes, coronary artery disease, preoperative antiplatelet medications, preoperative statin use, and lower rates of discharge and follow-up antiplatelet medications. On univariable analysis, the cases of IVCF thrombosis also had higher rates of pulmonary embolism and VTE on admission, internal jugular venous access (vs femoral vein access), temporary IVCF use, follow-up anticoagulation, follow-up IVCF complication, follow-up access site thrombosis, and rates of new or propagated deep vein thrombosis at follow-up, and longer postoperative hospital stays. Multivariable analysis demonstrated that the independent predictors of IVCF thrombosis included new or propagated deep vein thrombosis at follow-up (hazard ratio [HR], 16.3; 95% confident interval [CI], 9.8-27.3; P < .001), no antiplatelet therapy at follow-up (HR, 4.8; 95% CI, 1.9-12.5; P = .001), internal jugular venous access (HR, 2.2; 95% CI, 1.4-3.5; P = .001), the presence of VTE on admission (HR, 2.7; 95% CI, 1.4-5.1; P = .002), and temporary IVCF placement (HR, 2.5; 95% CI, 1.1-5.6; P = .031). In an analysis of the subgroup of patients with VTE on admission, similar predictive factors were identified in a multivariable model. Massive pulmonary embolism was also predictive of IVCF thrombosis in this subgroup. CONCLUSIONS: The rate of IVCF thrombosis remained low in a contemporary international database. The results from the present study of >5000 patients with IVCFs suggest that antiplatelet therapy should be administered after IVCF placement to decreased the risk of IVCF thrombosis.

Superior sagittal sinus-to-internal jugular vein bypass shunt with covered stent construct for intractable intracranial hypertension resulting from iatrogenic supratorcular sinus occlusion: technical note.

BACKGROUND: Acute occlusion of the posterior sagittal sinus may lead to dramatic increase in intracranial pressure (ICP), refractory to standard treatment. Hybrid vascular bypass of cranial venous outflow into the internal jugular vein (IJV) has seldom been described for this in recent neurosurgical literature. OBJECTIVE: To describe creation of a novel vascular bypass shunt from the superior sagittal sinus (SSS) to internal jugular vein (IJV) utilizing a covered stent-Dacron graft construct for control of refractory ICP. METHODS: We illustrate a patient with refractory ICP increases after acute sinus ligation that was performed to halt torrential bleeding from intraoperative injury. A temporary shunt was created that successfully controlled ICP. From the promising results of the temporary shunt, we utilized a prosthetic hybrid bypass graft to function as a shunt from the sagittal sinus to IJV. Yet the associated anticoagulation led to complications and a poor outcome. RESULTS: Rapid and sustained ICP reduction can be expected after sagittal sinus-to-jugular bypass shunt placement in acute sinus occlusion. Details of the surgical technique are described. Heparin anticoagulation, while imperative, is also associated with worrisome complications. CONCLUSION: Acute occlusion of posterior third of sagittal sinus carries a very malignant clinical course. Intractable intracranial hypertension from acute sinus occlusion may be effectively treated with a SSS-IJV bypass shunt. A covered stent construct provides an effective vascular bypass conduit. However, the anticoagulation risk can lead to fatal outcomes. The neurosurgeon must always strive for primary repair of an injured sinus.

Occlusion of the Celiac Artery during Endovascular Thoracoabdominal Aortic Aneurysm Repair Is associated with Increased Perioperative Morbidity and Mortality.

BACKGROUND: Some studies suggest that celiac artery coverage during elective endovascular thoracoabdominal aortic aneurysm (TAAA) repair is safe given sufficient collateralization of visceral organ perfusion from the superior mesenteric artery. However, there is concern that celiac artery coverage may lead to increased risk of foregut or spinal cord ischemia with an attendant increased risk of mortality. We sought to investigate rates of bowel ischemia, spinal cord ischemia, and 30-day mortality associated with celiac artery coverage during TEVAR and complex EVAR. METHODS: The Society for Vascular Surgery Vascular Quality Initiative database was queried for TEVAR and complex EVAR cases from 2012 to 2018. Inclusion criteria included TAAA pathology and endograft extension to aortic zone 6. Patients with aortic rupture, trauma, prior thoracic aortic surgery, known preoperative occlusion of the left subclavian superior mesenteric, or celiac arteries were excluded. Cases with intraoperative celiac artery occlusion (CAO) were compared retrospectively to cases with celiac artery preservation (CAP). Primary outcomes included 30-day mortality and a composite end point of 30-day mortality, spinal cord ischemia (transient or permanent lower extremity neurologic deficit), and bowel ischemia (colonoscopic evidence of ischemia, bloody stools in a patient who dies prior to colonoscopy or laparotomy, or other documented clinical diagnosis). Univariable comparisons were performed using chi-squared tests and Student's t-tests, as appropriate. Multivariable logistic regression analyses were employed to identify independent predictors of outcome. RESULTS: There were 628 cases identified for inclusion in the study. Patients undergoing CAO (n = 44) were more likely to be female or to have higher rates of preoperative spinal drain use, American Society of Anesthesiologists score ≥3, low preop hemoglobin, and/or symptomatic presentation, but fewer mean number of aortic zones covered. CAO was associated with higher 30-day mortality (5 of 44, 11%) compared to CAP (23 of 584, 4%), P = 0.039. The composite end point occurred at a significantly greater proportion for those who had CAO (10 of 44, 23%) compared to CAP (53 of 584, 9%, P = 0.008), driven by higher rates of 30-day mortality and bowel ischemia (9% vs. 2%, P = 0.026). By multivariate analysis, CAO was predictive of 30-day mortality (odds ratio [OR] = 3.9, 95% confidence interval [CI] = 1.1-13.8, P = 0.04) and the composite endpoint (OR = 3.0, 95% CI = 1.1-8.5, P = 0.03). Increasing procedure time was also associated with 30-day mortality (OR = 1.4, 95% CI = 1.1-1.7, P < 0.001) and the composite end point (OR = 1.4, 95% CI = 1.1-1.6, P < 0.001). CONCLUSIONS: For those treated for TAAAs, CAO was independently predictive of increased 30-day mortality and a composite end point of perioperative mortality, spinal cord ischemia, and bowel ischemia. When treating patients with extensive aortic aneurysmal disease, physicians should attempt to preserve the celiac artery, by revascularization or avoiding ostium coverage, whenever feasible.

Previous thoracic aortic repair is not associated with adverse outcomes after thoracic endovascular aortic repair.

BACKGROUND: As many as 20% of patients who have undergone previous thoracic aortic repair will require reintervention, which could entail thoracic endovascular aortic repair (TEVAR). A paucity of data is available on mortality and the incidence of spinal cord ischemia (SCI) and other postoperative complications associated with TEVAR after previous aortic repairs exclusive to the thoracic aorta. The aim of the present study was to assess the effect of previous thoracic aortic repair on the 30-day mortality and SCI outcomes for patients after TEVAR. METHODS: The Society for Vascular Surgery Vascular Quality Initiative database was queried for all cases of TEVAR from 2012 to 2018. Patients were excluded if they had undergone previous abdominal aortic repair, the TEVAR had extended beyond aortic zone 5, or SCI data were missing. The 3 cohorts compared were TEVAR with previous ascending aortic or aortic arch repair (group 1), TEVAR with previous descending thoracic aortic repair (group 2), and TEVAR without previous repair (group 3). The primary outcomes of interest were 30-day mortality and SCI. The secondary outcomes included stroke, myocardial infarction, cardiac complications, respiratory complications, postoperative length of stay, and reintervention. The patient variables were compared using χ2 tests, analysis of variance, or Kruskal-Wallis tests, as appropriate. Logistic regression analysis was performed to identify the predictors of 30-day mortality and SCI. RESULTS: A total of 4010 patients met the inclusion criteria, with 470 in group 1, 132 in group 2, and 3408 in group 3. The 30-day mortality was 4% (19 of 470) in group 1, 6% (8 of 132) in group 2, and 6% (213 of 3408) in group 3 (P = .17). The incidence of SCI was 3% (14 of 470) in group 1, 3% (4 of 132) in group 2, and 3.8% (128 of 3408) in group 3 (P = .65). Stroke, reintervention, myocardial infarction, and cardiac complications were not significantly different among the 3 groups. The incidence of respiratory complications was greatest for group 3 (11%; 360 of 3408) compared with groups 1 (9%; 44 of 470) and 2 (4%; 5 of 132; P = .034). Similarly, the postoperative length of stay was longest for group 3 (9.6 ± 19.4 days vs 8.2 ± 18.3 days for group 1 and 5.9 ± 8.6 days for group 2; P = .038). The independent predictors of 30-day mortality for all TEVAR patients included units of packed red blood cells transfused intraoperatively, urgent or emergent repairs, older age, increasing serum creatinine level, inability to perform self-care, total procedure time, occlusion of the left subclavian artery intraoperatively, distal endograft landing zone 5, and diabetes. The predictors of SCI included the total procedure time, urgent and emergent repairs, and increasing serum creatinine level. CONCLUSIONS: TEVAR after previous thoracic aortic repair was not associated with an increased risk of SCI or 30-day mortality compared with TEVAR without previous aortic repair.

Early extubation is associated with reduced length of stay and improved outcomes after elective aortic surgery in the Vascular Quality Initiative.

OBJECTIVE: Timing of extubation after open aortic procedures varies across hospitals. This study was designed to examine extubation timing and determine its effect on length of stay (LOS) and respiratory complications after elective open aortic surgery. METHODS: We studied extubation timing for 7171 patients undergoing elective open abdominal aortic aneurysm repair (2687 [37.5%]) or suprainguinal bypass for aortoiliac occlusive disease (4484 [62.5%]) from October 2010 to April 2015 in hospitals participating in the Vascular Quality Initiative (VQI). Our primary outcome was prolonged LOS (>7 days), and the secondary outcome was respiratory complications (pneumonia or reintubation). The association between extubation timing and outcomes was assessed using multivariable logistic regression mixed-effects models that adjusted for confounding factors at the patient and procedure level. A variable importance analysis was conducted using a chi-pie framework to identify factors contributing to the variability of extubation timing. RESULTS: The 7171 patients undergoing abdominal aortic surgery were a mean age of 65.4 (standard deviation, 10.2) years, and 63% were male. Extubation occurred (1) in the operating room (76.3%), (2) <12 hours (10.9%), (3) 12 to 24 hours (7.2%), or (4) >24 hours (5.6%) after surgery. Hospitals in the top quartile for case volume had the highest percentage of patients extubated in the operating room (82.8%). Patients least likely to be extubated in the operating room were older, more likely to have chronic obstructive pulmonary disease, require vasopressors, have higher estimated blood loss (EBL), and longer procedure times. After adjustment for patient, procedure, and institutional factors, delayed extubation was associated with prolonged LOS (<12 hours: odds ratio [OR], 1.4; 95% confidence interval [CI], 1.2-1.7; 12-24 hours: OR, 2.1; 95% CI, 1.7-2.7; >24 hours: OR, 5.3; 95% CI, 4.0-6.9), and pulmonary complications (<12 hours: OR, 1.9; 95% CI, 1.4-2.6; 12-24 hours: OR, 2.6; 95% CI, 1.8-3.6; >24 hours: OR, 9.6; 95% CI, 7.1-13.0) compared with those extubated in the operating room. Subset analysis of patients extubated in the operating room or <12 hours showed that extubation out of the operating room was associated with prolonged LOS (OR, 1.4; 95% CI, 1.2-1.7) and pulmonary complications (OR, 1.8; 95% CI, 1.3-2.5). The variable importance analysis demonstrated that EBL (26%) and procedure time (24%) accounted for half of the variation in extubation timing. CONCLUSIONS: Extubation in the operating room is associated with shorter LOS and morbidity after open aortic surgery. EBL, procedure time, and center variation account for variability in extubation timing. These data advocate for standardized perioperative respiratory care to reduce variation, improve outcomes, and reduce LOS.

Impact of Inferior Vena Cava Filter Placement on Short-Term Outcomes in Patients with Acute Pulmonary Embolism.

BACKGROUND: Inferior vena cava filters (IVCFs) have been associated with improved survival in patients with acute pulmonary embolism (PE) in some studies. However, without randomization, those with early mortality who did not receive an IVCF might have died prior to treatment decision about filter placement, falsely contributing a survival advantage to those receiving IVCF and biasing the results of previous observational studies. The objective of this study is to evaluate the impact of IVCF on in-hospital mortality after adjusting for this survivor treatment selection. METHODS: National Inpatient Sample data sets from 2009 to 2012 were analyzed to assess the impact of IVCF placement on in-hospital mortality in all patients with acute PE. Subgroup analyses were performed in those with high-risk PE (hemodynamic shock) and also for those with both shock and concomitant thrombolysis. Inverse propensity-score weighting was used to balance clinical and comorbid differences between filter and nonfilter groups. To account for survivor treatment selection bias, an extended Cox model was fitted with IVCF placement as a time-dependent covariate. RESULTS: We identified 263,955 patients with acute PE over this period; 36,702 (13.9%) received IVCF. Those receiving IVCF in the unadjusted cohort were older (IVCF: 66.3 ± 15.9 vs. non-IVCF: 62.4 ± 17.4; P < 0.001) with higher rates of shock (6.8% vs. 3.8%; P < 0.001), deep venous thrombosis (32.8% vs. 13.9%; P < 0.001), thrombolytic therapy (5.9% vs. 1.6%; P < 0.001), and lower crude mortality (6.0% vs. 6.7%; P < 0.001). Propensity weighted extended Cox analysis showed that IVCF placement did not significantly decrease mortality hazard compared to an untreated patient (hazard ratio [HR]: 0.93, 95% confidence interval [CI]: 0.89-1.01). Similar results were seen in the combined high-risk and thrombolysis (HR: 0.85, 95% CI: 0.60-1.21) subgroup and associated with worse outcomes in the high-risk (HR: 1.2, 95% CI 1.11-1.38) subgroup. CONCLUSIONS: Placement of IVCF in all patients with acute PE, in high-risk patients, or in high-risk patients concurrently treated with thrombolysis is not significantly associated with improvement of in-hospital mortality when accounting for survivor treatment selection bias.

Risk stratification for the development of respiratory adverse events following vascular surgery using the Society of Vascular Surgery's Vascular Quality Initiative.

OBJECTIVE: Postoperative respiratory adverse events (RAEs) are associated with high rates of morbidity and mortality in general surgery, however, little is known about these complications in the vascular surgery population, a frail subset with multiple comorbidities. The objective of this study was to describe the contemporary incidence of RAEs in vascular surgery patients, the risk factors for this complication, and the overall impact of RAEs on patient outcomes. METHODS: The Vascular Quality Initiative was queried (2003-2014) for patients who underwent endovascular abdominal aortic repair, open abdominal aortic aneurysm repair, thoracic endovascular aortic repair, suprainguinal bypass, or infrainguinal bypass. A mixed-effects logistic regression model determined the independent risk factors for RAEs. Using a random 85% of the cohort, a risk prediction score for RAEs was created, and the score was validated using the remaining 15% of the cohort, comparing the predicted to the actual incidence of RAE and determining the area under the receiver operating characteristic curve. The independent risk of in-hospital mortality and discharge to a nursing facility associated with RAEs was determined using a mixed-effects logistic regression to control for baseline patient characteristics, operative variables, and other postoperative adverse events. RESULTS: The cohort consisted of 52,562 patients, with a 5.4% incidence of RAEs. The highest rates of RAEs were seen in current smokers (6.1%), recent acute myocardial infarction (10.1%), symptomatic congestive heart failure (9.9%), chronic obstructive pulmonary disease requiring oxygen therapy (11.0%), urgent and emergent procedures (6.4% and 25.9%, respectively), open abdominal aortic aneurysm repairs (17.6%), in situ suprainguinal bypasses (9.68%), and thoracic endovascular aortic repairs (9.6%). The variables included in the risk prediction score were age, body mass index, smoking status, congestive heart failure severity, chronic obstructive pulmonary disease severity, degree of renal insufficiency, ambulatory status, transfer status, urgency, and operative type. The predicted compared with the actual RAE incidence were highly correlated, with a correlation coefficient of 0.943 (P < .0001) and a c-statistic = 0.818. RAEs had a significantly higher rates of in-hospital mortality (25.4% vs 1.2%; P < .0001; adjusted odds ratio, 5.85; P < .0001), and discharge to a nursing facility (57.8% vs 19.0%; P < .0001; adjusted odds ratio, 3.14; P < .0001). CONCLUSIONS: RAEs are frequent and one of the strongest risk factors for in-hospital mortality and inability to be discharged home. Our risk prediction score accurately stratifies patients based on key demographics, comorbidities, presentation, and operative type that can be used to guide patient counseling, preoperative optimization, and postoperative management. Furthermore, it may be useful in developing quality benchmarks for RAE following major vascular surgery.

Effects of Gender Differences on Short-term Outcomes in Patients with Type B Aortic Dissection.

BACKGROUND: Gender-related differences in type B aortic dissection (TBAD) presentation and outcomes are not well understood. The objective of this study is to assess the impact of gender on short-term outcomes in patients with TBAD. METHODS: Patients with TBAD were identified from the National Inpatient Sample datasets from 2009 to 2012 according to previously published methods. The primary outcomes of interest were in-hospital mortality and major complications (renal, cardiac, pulmonary, paraplegia, and stroke related) between men and women. An inverse propensity-weighted regression was used to balance comorbid and clinical presentation differences. Subgroup analyses were performed on those undergoing endovascular (thoracic endovascular aortic repair [TEVAR]) and open repair, and for elderly patients over the age of 70. RESULTS: We identified 9855 patients with TBAD; women were fewer (43.6%, n = 4293) and presented at a later age (69.8 ± 15.5 vs. 62.8 ± 15.6, P < 0.001). Women had more comorbidities (median Elixhauser 4 [interquartile range, IQR 2-5] vs. 3 [IQR 2-5], P < 0.001) and were more often managed nonoperatively (87.4% vs. 81.8%, P < 0.001) compared with men. For those undergoing intervention, 58% (n = 903) had open repair and TEVAR rates were higher in women compared with men (45.6% vs. 40.0%, P < 0.001). Unadjusted mortality rates did not differ significantly by gender (male: 11.6% vs. female: 10.7%). In an adjusted propensity-weighted regression, gender did not significantly affect in-hospital mortality or stroke rates, but women were less likely to have acute renal failure during their hospitalization and more likely to experience cardiac events when undergoing open repair. Elderly women were also less likely to experience acute renal failure but had higher odds of cardiac events regardless of intervention compared with elderly men. CONCLUSIONS: In comparison with men, women with TBAD presented at a later age, were more likely to undergo TEVAR, sustain a perioperative cardiac event with open surgery, and were less likely to experience acute renal complications overall. Elderly women were additionally more likely to sustain a cardiac event regardless of operative status. Future studies should attempt to identify anatomic and epidemiologic reasons for these differences.

Bio-absorbable antibiotic impregnated beads for the treatment of prosthetic vascular graft infections.

OBJECTIVE: There is limited investigation into the use of bio-absorbable antibiotic beads for the treatment of prosthetic vascular graft infections. Our goal was to investigate the rates of infection eradication, graft preservation, and limb salvage in patients who are not candidates for graft explant or extensive reconstruction. METHODS: A retrospective review of patients implanted with antibiotic impregnated bio-absorbable calcium sulfate beads at a major university center was conducted. RESULTS: Six patients with prosthetic graft infections were treated with bio-absorbable antibiotics beads from 2012-2014. Grafts included an aortobifemoral, an aorto-hepatic/superior mesenteric artery, and four extra-anatomic bypasses. Pathogens included Gram-positive and Gram-negative bacteria. Half of the patients underwent graft explant with reconstruction and half debridement of the original graft, all with antibiotic bead placement around the graft. Mean follow-up was 7.3 ± 8.3 months; all patients had infection resolution, healed wounds, and 100% graft patency, limb salvage, and survival. CONCLUSION: This report details the successful use of bio-absorbable antibiotic beads for the treatment prosthetic vascular graft infections in patients at high risk for graft explant or major vascular reconstruction. At early follow-up, we demonstrate successful infection suppression, graft preservation, and limb salvage with the use of these beads in a subset of vascular patients.

Risk Factors for Long-Term Mortality and Amputation after Open and Endovascular Treatment of Acute Limb Ischemia.

BACKGROUND: Acute limb ischemia (ALI) is a highly morbid and fatal vascular emergency with little known about contemporary, long-term patient outcomes. The goal was to determine predictors of long-term mortality and amputation after open and endovascular treatment of ALI. METHODS: A retrospective review of ALI patients at a single institution from 2005 to 2011 was performed to determine the impact of revascularization technique on 5-year mortality and amputation. For each main outcome 2 multivariable models were developed; the first adjusted for preoperative clinical presentation and procedure type, the second also adjusted for postoperative adverse events (AEs). RESULTS: A total of 445 limbs in 411 patients were treated for ALI. Interventions included surgical thrombectomy (48%), emergent bypass (18%), and endovascular revascularization (34%). Mean age was 68 ± 15 years, 54% were male, and 23% had cancer. Most patients presented with Rutherford classification IIa (54%) or IIb (39%). The etiology of ALI included embolism (27%), in situ thrombosis (28%), thrombosed bypass grafts (32%), and thrombosed stents (13%). Patients treated with open procedures had significantly more advanced ischemia and higher rates of postoperative respiratory failure, whereas patients undergoing endovascular interventions had higher rates of technical failure. Rates of postprocedural bleeding and cardiac events were similar between both treatments. Excluding Rutherford class III patients (n = 12), overall 5-year mortality was 54% (stratified by treatment, 65% for thrombectomy, 63% for bypass, and 36% for endovascular, P < 0.001); 5-year amputation was 28% (stratified by treatment, 18% for thrombectomy, 27% for bypass, and 17% for endovascular, P = 0.042). Adjusting for comorbidities, patient presentation, AEs, and treatment method, the risk of mortality increased with age (hazard ratio [HR] = 1.04, P < 0.001), female gender (HR = 1.50, P = 0.031), cancer (HR = 2.19, P < 0.001), fasciotomy (HR = 1.69, P = 0.204) in situ thrombosis or embolic etiology (HR = 1.73, P = 0.007), cardiac AEs (HR = 2.25, P < 0.001), respiratory failure (HR = 2.72, P < 0.001), renal failure (HR = 4.70, P < 0.001), and hemorrhagic events (HR = 2.25, P = 0.003). Risk of amputation increased with advanced ischemia (Rutherford IIb compared with IIa, HR = 2.57, P < 0.001), thrombosed bypass etiology (HR = 3.53, P = 0.002), open revascularization (OR; HR = 1.95, P = 0.022), and technical failure of primary intervention (HR = 6.01, P < 0.001). CONCLUSIONS: After the treatment of ALI, long-term mortality and amputation rates were greater in patients treated with open techniques; OR patients presented with a higher number of comorbidities and advanced ischemia, while also experiencing a higher rate of major postoperative complications. Overall, mortality rates remained high and were most strongly associated with baseline comorbidities, acuity of presentation, and perioperative AEs, particularly respiratory failure. Comparatively, amputation risk was most highly associated with advanced ischemia, thrombosed bypass, and failure of the initial revascularization procedure.

Endovascular management of symptomatic gastrointestinal complications associated with retrievable inferior vena cava filters.

OBJECTIVE: With the increase in retrievable inferior vena cava (IVC) filter use, a higher than expected reported rate of pericaval tine penetration is observed. Symptomatic gastrointestinal (GI) complications associated with retrievable IVC filters have been documented; however, their management remains controversial. We describe a series of GI complications of retrievable IVC filters, detailing the spectrum of presenting symptoms and multiple treatment options, including the safety of endovascular retrieval. METHODS: A retrospective chart review was performed to describe the presentation, diagnosis, and treatment of patients with symptomatic GI complications associated with retrievable IVC filters from 2008 to 2014. RESULTS: Nine patients had symptomatic GI complications associated with a retrievable IVC filter (two G2 Recovery [Bard Peripheral Vascular, Tempe, Ariz], seven Celect [Cook Medical, Bloomington, Ind]; six women; age range, 17-81 years). All patients had small bowel perforation on computed tomography scan, four confirmed by esophagogastroduodenoscopy. Concomitant aortic and vertebral penetration occurred in seven and five patients, respectively. Patients presented with various abdominal complaints; one patient presented in acute sepsis. Two patients underwent laparotomy without complications. The remaining seven patients had attempted endovascular retrieval, six of which were successful. One patient's IVC filter was unable to be retrieved, and he was managed medically. Of the six patients who had successful endovascular retrieval, all had resolution of their symptoms with no complications, except for transient sepsis in a single patient who was not receiving periprocedural antibiotics. A follow-up computed tomography scan was performed 48 to 72 hours after endovascular retrieval and ruled out duodenal leak in all patients. Long-term follow-up demonstrated continued resolution of GI symptoms without further episodes of deep venous thrombosis or pulmonary embolism. CONCLUSIONS: GI complications of retrievable IVC filters are manifested with a wide spectrum of symptoms and frequent concomitant aortic and vertebral penetration. Endovascular retrieval can be safely used as a first-line therapy even in the setting of small bowel and aortic penetration.

Model for end-stage liver disease score predicts adverse events related to ventricular assist device therapy.

BACKGROUND: The Model for End-stage Liver Disease (MELD) score is a marker of multisystem organ dysfunction. It has been used to predict outcomes in patients undergoing hepatic and nonhepatic interventions. End-stage heart disease exhibits a varying degree of multiorgan dysfunction, which impacts the adverse events related to ventricular assist device (VAD) therapy. Our aim for the present study was to investigate the value of MELD score in predicting adverse events related with VAD therapy. METHODS: Data were collected on demographics, clinical characteristics, MELD score; Interagency Registry for Mechanically Assisted Circulatory Support-defined VAD adverse events within the first 6 months, and survival from VAD recipients (n=286; from 1996 to 2009). Univariable, multivariable, and Cox regression analyses were performed using SAS software (SAS Institute, Cary, NC). RESULTS: The mean MELD score was 14.4±5.9. Actuarial incidence of infections, bleeding events, and cardiovascular dysfunction at 6 months was 65.4%, 52.1%, and 45.6%, respectively. Multivariable Cox proportional hazards model (controlling for gender, type of device, diagnosis, intention to treat, urgency, and inotropic use) confirmed that MELD score predicted mortality, respiratory, and renal dysfunction at 6 months (p<0.01). CONCLUSIONS: Preoperative MELD score is predictive of mortality, respiratory, and renal dysfunction at 6 months after controlling for gender, type of device, diagnosis, intention to treat, urgency, and inotropic use. The MELD score may be used as a quantitative tool to assess the adverse events associated with VAD therapy.

Early adverse events as predictors of 1-year mortality during mechanical circulatory support.

BACKGROUND: Ventricular assist devices (VADs) provide effective treatment for end-stage heart failure; however, most patients experience > or =1 major adverse events (AEs) while on VAD support. Although early, non-fatal AEs may increase the risk of later death during VAD support, this relationship has not been established. Therefore, we sought to determine the impact on 1-year mortality of AEs occurring during the first 60 days of VAD support. METHODS: A retrospective analysis was performed using prospectively collected data from a single-site database for patients aged > or =18 years receiving left ventricular or biventricular support during 1996 to 2008 and who survived >60 days on VAD support. Fourteen major classes of AEs occurring during this 60-day period were examined. One-year survival rates of patients with and without each major AE were compared. RESULTS: The study included 163 patients (80% men; mean age, 49.5 years), of whom 87% were European American, 72% had left ventricular support, and 83% were bridge to transplant. The occurrence of renal failure, respiratory failure, bleeding events, and reoperations during the first 60 days after implantation significantly increased the risk of 1-year mortality. After controlling for gender, age, VAD type, and intention to treat, renal failure was the only major AE significantly associated with later mortality (hazard ratio, 2.96; p = .023). CONCLUSIONS: Specific AEs, including renal failure, respiratory and bleeding events, and reoperations, significantly decrease longer-term survival. Renal failure conferred a 3-fold increased risk of 1-year mortality. Peri-operative management should focus on strategies to mitigate risk for renal failure in order to maximize later outcomes.