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.

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.

Society for Vascular Surgery clinical practice guidelines of thoracic endovascular aortic repair for descending thoracic aortic aneurysms.

Thoracic aortic diseases, including disease of the descending thoracic aorta (DTA), are significant causes of death in the United States. Open repair of the DTA is a physiologically impactful operation with relatively high rates of mortality, paraplegia, and renal failure. Thoracic endovascular aortic repair (TEVAR) has revolutionized treatment of the DTA and has largely supplanted open repair because of lower morbidity and mortality. These Society for Vascular Surgery Practice Guidelines are applicable to the use of TEVAR for descending thoracic aortic aneurysm (TAA) as well as for other rarer pathologic processes of the DTA. Management of aortic dissections and traumatic injuries will be discussed in separate Society for Vascular Surgery documents. In general, there is a lack of high-quality evidence across all TAA diseases, highlighting the need for better comparative effectiveness research. Yet, large single-center experiences, administrative databases, and meta-analyses have consistently reported beneficial effects of TEVAR over open repair, especially in the setting of rupture. Many of the strongest recommendations from this guideline focus on imaging before, during, or after TEVAR and include the following: In patients considered at high risk for symptomatic TAA or acute aortic syndrome, we recommend urgent imaging, usually computed tomography angiography (CTA) because of its speed and ease of use for preoperative planning. Level of recommendation: Grade 1 (Strong), Quality of Evidence: B (Moderate). If TEVAR is being considered, we recommend fine-cut (≤0.25 mm) CTA of the entire aorta as well as of the iliac and femoral arteries. CTA of the head and neck is also needed to determine the anatomy of the vertebral arteries. Level of recommendation: Grade 1 (Strong), Quality of Evidence: A (High). We recommend routine use of three-dimensional centerline reconstruction software for accurate case planning and execution in TEVAR. Level of recommendation: Grade 1 (Strong), Quality of Evidence: B (Moderate). We recommend contrast-enhanced computed tomography scanning at 1 month and 12 months after TEVAR and then yearly for life, with consideration of more frequent imaging if an endoleak or other abnormality of concern is detected at 1 month. Level of recommendation: Grade 1 (Strong), Quality of Evidence: B (Moderate). Finally, based on our review, in patients who could undergo either technique (within the criteria of the device's instructions for use), we recommend TEVAR as the preferred approach to treat elective DTA aneurysms, given its reduced morbidity and length of stay as well as short-term mortality. Level of recommendation: Grade 1 (Strong), Quality of Evidence: A (High). Given the benefits of TEVAR, treatment using a minimally invasive approach is largely based on anatomic eligibility rather than on patient-specific factors, as is the case in open TAA repair. Thus, for isolated lesions of the DTA, TEVAR should be the primary method of repair in both the elective and emergent setting based on improved short-term and midterm mortality as well as decreased morbidity.

Endograft exclusion of the false lumen restores local hemodynamics in a model of type B aortic dissection.

OBJECTIVE: Endovascular intervention in uncomplicated type B dissection has not been shown conclusively to confer benefit on patients. The hemodynamic effect of primary entry tear coverage is not known. Endovascular stent grafts were deployed in a model of aortic dissection with multiple fenestrations to study these effects. It is hypothesized that endograft deployment will lead to restoration of parabolic true lumen flow as well as elimination of false lumen flow and transluminal jets and vortices locally while maintaining distal false lumen canalization. METHODS: Thoracic stent grafts were placed in silicone models of aortic dissection with a compliant and mobile intimal flap and installed in a flow loop. Pulsatile fluid flow was established with a custom positive displacement pump, and the models were imaged by four-dimensional flow magnetic resonance imaging. Full flow fields were acquired in the models, and velocities were extracted to calculate flow rates, reverse flow indices, and oscillatory shear index, the last two of which are measures of stagnant and disturbed flows. RESULTS: Complete obliteration of the false lumen was achieved in grafted aorta, with normal parabolic flow profiles in the true lumen (maximal velocity, 30.4 ± 8.4 cm/s). A blind false lumen pouch was created distal to this with low-velocity (5.8 ± 2.7 cm/s) and highly reversed (27.9% ± 13.9% reverse flow index) flows. In distal free false lumen segments, flows were comparable to ungrafted conditions with maximal velocities on the order of 7.0 ± 2.1 cm/s. Visualization studies revealed forward flow in these regions with left-handed vortices from true to false lumen. Shear calculations in free false lumen regions demonstrated reduced oscillatory shear index. CONCLUSIONS: Per the initial hypothesis, endovascular grafting improved true lumen hemodynamics in the grafted region. Just distally, a prothrombotic flow regimen was noted in the false lumen, yet free false lumen distal to this remained canalized. Clinically, this suggests a need for advancing endovascular intervention beyond sole entry tear coverage to prevent further false lumen canalization through uncovered fenestrations.

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.

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.

A Novel Quality of Life Instrument for Patients with an Abdominal Aortic Aneurysm.

OBJECTIVE: The surveillance and treatment of abdominal aortic aneurysms (AAAs) may impact patient quality of life (QOL). A novel AAA specific QOL instrument was developed and validated to quantify the impact of AAA surveillance on QOL. METHODS: The study was performed in two phases: development (2011-2013) and validation (2013-2014) of a survey instrument. Content was informed by focus groups at three centres (22 patients) and two multidisciplinary physician focus groups (6 vascular surgeons, 7 primary care providers). Cognitive interviews (17 patients) ensured questions were understood as intended. The final survey was mailed to AAA patients at six US institutions. Patients were scored on two AAA specific domains of QOL: emotional impact (EIS) and behavioural change (BCS), range 0-100 with higher scores indicating worse quality of life. Test retest reliability and internal consistency were assessed. Discriminant validity was determined by comparing scores between patients under surveillance vs. those who had undergone AAA repair. Scores were externally validated by correlation with the Short Form (SF)-12. RESULTS: A total of 1,008 (73%) of 1,373 patients returned surveys: 351 (35%) were under surveillance, 657 (65%) had undergone repair (endovascular, 414; open, 179; unsure, 64). Median EIS was 11 (range 0-95; IQR 7-26). Median BCS was 13 (range 0-100; IQR 9-47). To test reliability, 337 patients repeated the survey after four weeks with no significant differences between scores over time. EIS and BCS demonstrated good internal consistency (Cronbach's Alpha 0.85 and 0.75 respectively). There was strong correlation between scores (r = 0.53) and both related moderately to SF-12 scores (r = 0.45 and r = 0.39, respectively). Patients under AAA surveillance had worse EIS than repair patients (22 vs. 13; p < .001). Patients with a higher perceived rupture risk had a worse EIS (45 vs. 12; p < .001) and BCS (30 vs. 13; p < .001). CONCLUSIONS: An AAA specific QOL instrument was successfully created and validated. The range of impact on QOL by AAA surveillance is broad. For most patients the impact is minimal, but for some, especially those with a greater perceived rupture risk, it is severe.

Contemporary evaluation of mortality and stroke risk after thoracic endovascular aortic repair.

OBJECTIVE: During the past decade, thoracic endovascular aortic repair (TEVAR) has increased as a treatment option for a variety of aortic pathologic processes. Despite this rise in the use of thoracic stent grafts, real-world outcomes from a robust, adjudicated, contemporary data set have yet to be reported. Previous studies have shown periprocedural mortality rates between 1.5% and 9.5% and procedure-related stroke rates of 2.3% to 8.2%. With advances in device engineering and increased experience of physicians, we hypothesized that the rates of these complications would be reduced in a more recent sample set. The purpose of this study was to determine current rates of mortality and stroke after TEVAR, to identify risk factors that contribute to 30-day mortality, and to develop a simple scoring system that allows risk stratification of patients undergoing TEVAR. METHODS: We examined the 30-day mortality rate after TEVAR using the 2013 to 2014 American College of Surgeons National Surgical Quality Improvement Program database. Patients undergoing TEVAR for all aortic disease were identified using procedure codes. Bivariate analyses were performed to evaluate the association of preoperative, intraoperative, and postoperative variables with 30-day mortality, followed by multivariable logistic analysis using preoperative variables only, with P < .10 as the criterion for model entry. The predictive logistic model was internally validated by cross-validation. Variables included in the multivariable model were used to develop a risk score. RESULTS: There were 826 patients included. The 30-day mortality and stroke rates were 7.63% (n = 63) and 4.5% (n = 37), respectively. In regression analysis, mortality was independently associated with age ≥80 years (odds ratio [OR], 2.32; 95% confidence interval [CI], 1.25-4.31), emergency case (OR, 2.61; 95% CI, 1.39-4.90), American Society of Anesthesiologists classification >3 (OR, 2.89; 95% CI, 1.34-6.24), transfusion >4 units in the 72 hours before surgery (OR, 2.86; 95% CI, 1.30-6.28), preoperative creatinine concentration ≥1.8 mg/dL (OR, 2.07; 95% CI, 1.05-4.08), and preoperative white blood cell count ≥12 × 109/L (OR, 2.65; 95% CI, 1.41-4.96). Incorporating these factors, a 6-point risk score was generated and demonstrated high predictability for overall 30-day mortality. CONCLUSIONS: Recent data from a national, retrospective data set demonstrate that high perioperative mortality and stroke rates have persisted during the last decade. The risk score derived from this data set is simple and convenient and serves as a prognostic tool in the preoperative risk stratification of patients being evaluated for TEVAR.

GSTP1 Loss results in accumulation of oxidative DNA base damage and promotes prostate cancer cell survival following exposure to protracted oxidative stress.

BACKGROUND: Epigenetic silencing of glutathione S-transferase π (GSTP1) is a hallmark of transformation from normal prostatic epithelium to adenocarcinoma of the prostate. The functional significance of this loss is incompletely understood. The present study explores the effects of restored GSTP1 expression on glutathione levels, accumulation of oxidative DNA damage, and prostate cancer cell survival following oxidative stress induced by protracted, low dose rate ionizing radiation (LDR). METHODS: GSTP1 protein expression was stably restored in LNCaP prostate cancer cells. The effect of GSTP1 restoration on protracted LDR-induced oxidative DNA damage was measured by GC-MS quantitation of modified bases. Reduced and oxidized glutathione levels were measured in control and GSTP1 expressing populations. Clonogenic survival studies of GSTP1- transfected LNCaP cells after exposure to protracted LDR were performed. Global gene expression profiling and pathway analysis were performed. RESULTS: GSTP1 expressing cells accumulated less oxidized DNA base damage and exhibited decreased survival compared to control LNCaP-Neo cells following oxidative injury induced by protracted LDR. Restoration of GSTP1 expression resulted in changes in modified glutathione levels that correlated with GSTP1 protein levels in response to protracted LDR-induced oxidative stress. Survival differences were not attributable to depletion of cellular glutathione stores. Gene expression profiling and pathway analysis following GSTP1 restoration suggests this protein plays a key role in regulating prostate cancer cell survival. CONCLUSIONS: The ubiquitous epigenetic silencing of GSTP1 in prostate cancer results in enhanced survival and accumulation of potentially promutagenic DNA adducts following exposure of cells to protracted oxidative injury suggesting a protective, anti-neoplastic function of GSTP1. The present work provides mechanistic backing to the tumor suppressor function of GSTP1 and its role in prostate carcinogenesis.

A national survey of disease-specific knowledge in patients with an abdominal aortic aneurysm.

OBJECTIVE: Patient education is a fundamental responsibility of medical providers caring for patients with abdominal aortic aneurysms (AAA). We sought to evaluate and quantify AAA-specific knowledge in patients under AAA surveillance and in patients who have undergone AAA repair. METHODS: In 2013, 1373 patients from 6 U.S. institutions were mailed an AAA-specific quality of life and knowledge survey. Of these patients, 1008 (73%) returned completed surveys for analysis. The knowledge domain of the survey consisted of nine questions. An AAA knowledge score was calculated for each patient based on the proportion of questions answered correctly. The score was then compared according to sex, race, and education level. Surveillance and repaired patients were also compared. RESULTS: Among 1008 survey respondents, 351 were under AAA surveillance and 657 had AAA repair (endovascular repair, 414; open, 179; unknown, 64). The majority of patients (85%) reported that their "doctor's office" was their most important source of AAA information. The "Internet" and "other written materials" were each reported as the most important source of information 5% of the time with "other patients" reported 2% of the time. The mean AAA knowledge score was 47% (range 0%-100%; standard deviation, 23%) with a broad variation in percentage correct between questions. Thirty-two percent of respondents did not know that larger AAA size increases rupture risk, and 64% did not know that AAA runs in families. Only 15% of patients answered six or more of the nine questions correctly, and 23% of patients answered two or fewer questions correctly. AAA knowledge was significantly greater in men compared with women, whites compared with nonwhites, high school graduates compared with nongraduates, and surveillance compared with repaired patients. CONCLUSIONS: In a national survey of AAA-specific knowledge, patients demonstrated poor understanding of their condition. This may contribute to anxiety and uninformed decision making. The need for increased focus on education by vascular providers is a substantial unmet need.

The Readmission Event after Vascular Surgery: Causes and Costs.

BACKGROUND: The study evaluates the readmission diagnoses after vascular surgical interventions and the associated hospital costs. METHODS: Patients readmitted after undergoing carotid artery stenting (CAS), carotid endarterectomy (CEA), infrarenal endovascular abdominal aortic aneurysm repair (EVAR), open abdominal aortic aneurysm repair (OAAA), suprainguinal revascularization (SUPRA), or infrainguinal revascularization (INFRA) between January 1, 2008 and October 20, 2013 at a single academic institution were retrospectively identified. Demographic, preoperative, and postoperative event variables were obtained by chart review. The diagnoses and the costs of the readmission event were obtained by chart review and from hospital financial data. Readmission indications were grouped as unrelated or planned readmissions, procedure-specific complications, wound complications, cardiac causes, and other. Univariate analyses of categorical variables were performed with χ2 or Fisher exact test where appropriate. Continuous variables were analyzed using the Wilcoxon rank-sum test. RESULTS: A total of 1,170 patient records were identified. Thirty-day readmission occurred in 112 patients (9.6%). The readmission rate was significantly different between groups: 4.5% in CAS (n = 8/177), 8.5% in CEA (21/246), 5.8% in EVAR (18/312), 11.4% in OAAA (4/35), 15.6% in INFRA (33/212), 13.5% in SUPRA (24/178), and 40% in combined SUPRA and INFRA (4/10) (P < 0.0001). Readmissions were unrelated or planned in 19.6% of patients. Wound complications were the most common readmission diagnoses (36.6%, 41/112).There was a difference in the distribution of readmission indications among procedure groups, with wound complications being predominant in INFRA and SUPRA groups (60.6% and 58.3%, respectively), and cardiac events predominantly in EVAR patients (42%) (P < 0.001). In univariable analysis of predictors of readmission, significant preoperative factors were chronic obstructive pulmonary disease, renal insufficiency, and lower hematocrit. Significant postoperative predictors included any postoperative complication, number of complications, increased length of stay, wound complications, postoperative infections, blood transfusion, and reoperation. The median hospital cost for readmission for wound complications was 29,723 USD (interquartile range 23,841-36,878), and for cardiac complications was 39,784 USD (26,305-46,918). The median cost of readmission for bypass graft occlusion was 33,366 USD (20,530-43,170). The median length of stay also differed depending on the readmission diagnosis and was highest for bypass graft occlusion (8.5 days). CONCLUSIONS: Readmissions after vascular procedures are associated with high cost and hospital bed utilization. Wound complications continue to be the dominant readmission etiology. The characterization of these costs and risk factors in this study can allow for resource allocation to minimize preventable related readmissions. A significant proportion of readmissions after vascular interventions are planned or unrelated, which should be taken into consideration in metric benchmarking and performance comparisons.

Carotid artery stenting has increased risk of external carotid artery occlusion compared with carotid endarterectomy.

OBJECTIVE: The external carotid artery (ECA) can be an important source of cerebral blood flow in cases of high-grade internal carotid artery stenosis or occlusion. However, the treatment of the ECA is fundamentally different between carotid endarterectomy (CEA) and carotid artery stenting (CAS). CEA is routinely associated with endarterectomy of the ECA, whereas CAS excludes the ECA from direct flow. We hypothesize that these differences make ECA occlusion more common after CAS. Further, the impact of CAS on blood flow into the ECA is interesting because the flow from the stent into the ECA is altered in a way that may promote local inflammation and may influence in-stent restenosis (ISR). Thus, our objective was to use our institutional database to identify whether CAS increased the rate of ECA occlusion and, if it did, whether ECA occlusion was associated with ISR. METHODS: Patients undergoing CAS or CEA from February 2007 to February 2012 were identified from our institutional carotid therapy database. Preoperative and postoperative images of patients who followed up in our institution were included in the analysis of ECA occlusion and rates of ISR. RESULTS: There were 210 (67%) CAS patients and 207 (60%) CEA patients included in this analysis. Despite CAS patients being younger (68 vs 70 years), having shorter follow-up (12.5 vs 56.2 months), and being more likely to take clopidogrel (97% vs 35%), they had an increased rate of ECA occlusion (3.8%) compared with CEA patients (0.4%). CAS patients who went on to ECA occlusion had an increased incidence of prior neck irradiation (50% vs 15%; P = .03), but we did not identify an association of ECA occlusion with ISR >50%. CONCLUSIONS: Whereas prior publications have identified increased rates of external carotid stenosis, this is the first demonstration of increased ECA occlusion after CAS. However, ECA occlusion is uncommon (∼4%) and did not have an association with ISR >50%. Future work modeling ECA flow patterns before and after CAS will be used to further test this interaction.

Development and testing of a silicone in vitro model of descending aortic dissection.

BACKGROUND: Stanford type B dissection of the descending aorta is a potentially fatal condition that is poorly understood. Limited scientific understanding of the role of current interventional techniques, as well as heterogeneity in the condition, contributes to lack of consensus as to the most effective treatment strategy. This study introduces an anatomically accurate model for investigating aortic dissection in a laboratory setting. MATERIALS AND METHODS: A silicone model was fabricated and filled with fluid to mimic human blood. Flow was established, and the model was scanned using a four-dimensional flow magnetic resonance imaging protocol. On analysis, luminal flow rates were quantified by multiplying local velocity by included area. RESULTS: The upstream total flow was compared with the sum of the flow in the true and false lumens. The two values were within the margin of error. Furthermore, flow rates matched with the relative areas of each compartment. CONCLUSIONS: These results validate our model as a novel and unique system that mimics a type B aortic dissection and will allow for more sophisticated analysis of dissection physiology in future studies.

Late mortality in females after endovascular aneurysm repair.

BACKGROUND: Abdominal aortic aneurysm (AAA) rupture is an adverse arterial remodeling event with high mortality risk. Because females have increased rupture risk with smaller AAAs (<5.5 cm), many recommend elective repair before the AAA reaches 5.5 cm. Elective repair improves survival for large AAAs, but long-term benefits of endovascular aneurysm repair (EVAR) for small AAAs in females remain less understood. The objective of this study was to identify if differences in late mortality exist between females undergoing elective EVAR at our institution for small and/or slow-growing AAAs compared with those who meet standard criteria. METHODS: We retrospectively analyzed all patients that underwent EVAR for infrarenal AAA from June, 2009-June, 2013. We excluded patients that were male, treated emergently or for iliac artery aneurysm, and that received renal and/or mesenteric artery stenting. Patients did not meet anatomic criteria if preoperative AAA diameter was <5.5 cm or enlarged <0.5 cm over 6 mo. Late mortality was assessed from the social security death index. RESULTS: Thirty-six of 162 elective EVAR patients (22.2%) were female (mean follow-up, 37.2 mo). Twenty patients (55.6%) met AAA size and/or growth criteria, whereas 16 (44.4%) did not meet criteria. Despite comparable demographics, comorbidities, and complications, patients that did not meet criteria had higher late mortality (37.5% versus 5%; P = 0.03) with a trend toward increased reoperation rate (25% versus. 5%; P = 0.48). Meeting size and/or growth criteria decreased odds of late death (odds ratio, 0.09; 95% confidence intervals, 0.01-0.83). CONCLUSIONS: There is increased late mortality in females receiving elective EVAR at our institution for small and/or slow-growing AAAs. This late mortality may limit the benefits of EVAR for this population.

Smoking cessation is the least successful outcome of risk factor modification in uninsured patients with symptomatic peripheral arterial disease.

BACKGROUND: Patients with peripheral arterial disease (PAD) have multiple atherosclerotic risk factors. Risk factor modification can reduce severity of disease at presentation and improve treatment outcomes. The Trans-Atlantic Inter-Society Consensus II (TASC II) has issued several recommendations that are widely adopted by specialists. However, the ability to provide proper services to patients may depend on the specific patient's access to care, which is primarily determined by the presence of health insurance. The purpose of our study was to determine whether insurance status impairs the ability of patients with symptomatic PAD to meet select TASC II recommendations. METHODS: A retrospective review of patients with symptomatic PAD from August 2011 to May 2013 was conducted; demographic, preoperative, procedural, and standard outcome variables were collected. Patients were divided into the insured group (private insurance, Medicare, Medicaid) or the uninsured group (self-pay). Insurance status was analyzed for its association to select TASC II recommendations: smoking cessation, referral to smoking cessation program, low-density lipoprotein cholesterol <2.59 mmol/L (<100 mg/dL), low-density lipoprotein cholesterol <1.81 mmol/L (<70 mg/dL), patients with coexisting hyperlipidemia and diabetes, glycated hemoglobin <7%, systolic blood pressure <140 mm Hg, prescription of aspirin, and prescription of a statin. RESULTS: One hundred and forty-four patients with symptomatic PAD were identified. Insured patients were more likely to be African American, older at presentation, or have a diagnosis of congestive heart failure. There was no significant difference between insured and uninsured patients in success rates of low-density lipoprotein cholesterol targets (65.1% vs. 51.1% for <2.59 mmol/L; 24.3% vs. 19.1% for <1.81 mmol/L), glycated hemoglobin targets (61.9% vs. 61.1% for <7%), blood pressure control (51.1% vs. 50.0% for systolic blood pressure <140), aspirin use (72.8% vs. 59.6%), or statin use (77.2% vs. 63.5%). However, insured patients were more likely to quit smoking than uninsured patients (35.1% vs. 17.7%, P = 0.023). Furthermore, there was no difference in patterns of referral to a multidisciplinary smoking cessation program between the 2 groups (31.5% vs. 38.5%). CONCLUSIONS: Insurance status does not impair patients' ability to meet most TASC II guidelines to modify cardiovascular risk factors in patients who have access to health care. Uninsured patients are, however, less likely to cease smoking compared with insured patients, despite no significant difference in referral patterns between the 2 groups for multidisciplinary smoking cessation counseling. Future efforts to assist patients with symptomatic PAD with atherosclerotic risk factor modification should focus on aiding uninsured patients in smoking cessation efforts.

Influence of the hostile neck on restenosis after carotid stenting.

BACKGROUND: Carotid artery stenting (CAS) for carotid stenosis is favored over carotid endarterectomy (CEA) in patients with a hostile neck from prior CEA or cervical irradiation (XRT). However, the restenosis rate after CAS in patients with hostile necks is variable in the literature. The objective of this study was to quantify differences in the in-stent restenosis (ISR)/occlusion and reintervention rates after CAS in patients with and without a hostile neck. Here we hypothesize that patients with hostile necks have an increased ISR, and that this increase may add morbidity to these patients. MATERIALS AND METHODS: All patients undergoing CAS from 2007 to 2013 for carotid artery stenosis with follow-up imaging at our institution were queried from our carotid database (n = 236). Patients with hostile necks, including both CAS after prior CEA (n = 65) and prior XRT (n = 37), were compared with patients who underwent CAS for other reasons including both anatomical (n = 46) and medical comorbidities (n = 88). The primary end points were ISR, repeat intervention, and stent occlusion. Secondary end points of the study were stroke/myocardial infarction (MI)/death at 30 days, perioperative cardiovascular accident, transient ischemic attack, MI, groin access complications, hyperperfusion syndrome, and periprocedural hypotension or bradycardia. RESULTS: Despite the hostile neck cohort being younger and having lower incidence of chronic obstructive pulmonary disease, coronary artery disease, and renal insufficiency, they had a greater incidence of ISR (11% vs. 4%; P = .03) and required more reinterventions (8% vs. 2%; P = .04). Stent occlusion and periprocedural morbidity/mortality were not different between groups. CONCLUSIONS: Patients with hostile necks have increased risk of restenosis and need for reinterventions after CAS compared with patients without a hostile neck. However, they do not appear to have higher rates of stent occlusion or per-procedural events.

Domains that Determine Quality of Life in Vascular Amputees.

BACKGROUND: Although patients with critical limb ischemia (CLI) commonly undergo major limb amputation, the quality of life (QOL) of this group remains poorly described. Therefore, we sought to describe which domains vascular amputees consider important in determining their health-related QOL. METHODS: We performed 4 focus groups in patients who had major lower extremity amputations resulting from CLI. They were conducted at 4 distinct centers across the United States to ensure broad geographic, socioeconomic, and ethnic representation. RESULTS: Of 26 patients (mean age, 64 years), 19 (73%) were Caucasian, 6 (23%) were African American, and 1 (4%) was Native American. Nearly, three-quarter of patients were men (n = 19, 73%) and had a high-school education or more (n = 19, 73%). Overall, 8 (31%) were double amputees and 17 (65%) had diabetes. Time since amputation varied across patients and ranged from 3 months to more than 27 years (mean, 4.3 years). Patients stated that their current QOL was determined by impaired mobility (65%), pain (60%), progression of disease in the remaining limb (55%), and depression/frustration (54%). Across 26 patients, more than half (n = 16, 62%) described multiple prior revascularization procedures. Although most felt that their physician did his/her best to salvage the affected leg (85%), a sizable minority would have preferred an amputation earlier in their CLI treatment course (27%). Furthermore, when asked how their care might have been improved, patients reported that facilitating peer support (88%), more extensive rehabilitation and prosthetist involvement (71%), earlier mention of amputation as a possible outcome (54%), and the early discontinuation of narcotics (54%) were potential areas of improvement. CONCLUSIONS: Although QOL in vascular amputees seems primarily determined by mobility impairment, pain, and emotional perturbation, our focus groups identified that physician-controlled factors such as the timing of amputation, informed decision making, and postamputation support may also play an important role. The assessment of patient preferences regarding maintenance of mobility at the cost of increased pain versus relief of pain with amputation at a cost of diminished mobility is central to shared decision making in CLI treatment.

Stent graft therapy for false lumen aneurysmal degeneration in established type B aortic dissection (FADED) results in differential volumetric remodeling of the thoracic versus abdominal aortic segments.

BACKGROUND: Despite optimal medical therapy of type B aortic dissections, false lumen aneurysmal degeneration of these established dissections (FADED) occur over long term (>6 months). The efficacy of thoracic stent grafts (thoracic endovascular aortic repair [TEVAR]) in promoting aortic remodeling when placed at late time points remains controversial and was the focus of this investigation. METHODS: Utilizing tomographic scans, the volume of 6 distinct aortic compartments were calculated including the stented true lumen and stented false lumen (STL and SFL), below-stent true and false lumens (BSTL and BSFL), and the infrarenal aorta true and false lumens (IRA TL and IRA FL) when applicable. Cross-sectional areas were calculated at 1-cm intervals, collated, and volumetric ratios were derived from preoperative values. RESULTS: From 2004 to 2011, 21 patients met inclusion criteria. Complete false lumen (FL) thrombosis was achieved in 85.7% of SFL and 26.3% of BSFL. Volumetric analysis demonstrated that 71% of patients had increased STL volume and 71% had decreased SFL. In the below-stent region, 75% of patients had increased true lumen (TL) with 59% concurrently decreased FL volume. The IRA TL volume increased in 85% of patients and the IRA FL also expanded in 75% of this cohort. At the latest time point, overall growth was noted in the infrarenal aortic segment. CONCLUSIONS: Utilization of TEVAR in patients suffering from FADED can promote TL expansion with concurrent FL regression; however, progressive dilation in the total infrarenal aorta volume may occur and warrants close surveillance.

Anatomic characteristics of aortic transection: centerline analysis to facilitate graft selection.

BACKGROUND: Traumatic transection of the thoracic aorta is a life-threatening complication that most commonly occurs after high-speed motor vehicle collisions. Although such injuries were previously treated with open surgical reconstruction, they are now more commonly being treated with endovascularly placed stent grafts. Unfortunately, most stent grafts are designed for treating aortic aneurysmal disease instead of traumatic injury. Further refinements in stent graft technology depend on a thorough anatomic understanding of the transection injury process. METHODS: All patients with computed tomography (CT) evidence of blunt aortic injury (BAI) between 2006 and 2012 at a Level 1 trauma center were queried. Their initial CT scans were imported into the Intuition (Terarecon, Inc.) viewing program, and off-line centerline reconstruction was performed. Standard demographic data were collected in addition to anatomic characteristics, including aortic diameters and the relationship of the injury to the arch vessels. RESULTS: Thirty-five patients were identified. Three patients were injured proximal to the left subclavian artery. The average length from the left subclavian artery to the proximal site of injury was 16.2 mm (range 2-31 mm). Most patients had >15 mm of landing zone beyond the left subclavian artery. The range of proximal diameters ranged from 17 to 32 mm, with an average aortic diameter of 23.9 mm. The average length of injured aortic segment was 27 mm. CONCLUSIONS: In this contemporary series from a large trauma center, 91% of patients are anatomically able to be treated with a stent graft that does not require coverage of the left common carotid artery. Most patients have an aortic diameter that falls between 21 and 26 mm in diameter, as well as a short segment of injured artery. Centers interested in emergently treating aortic transections are able to do so while maintaining a limited stock of stent grafts that can be used to treat the majority of the population.

Characterization of resident surgeon participation during carotid endarterectomy and impact on perioperative outcomes.

INTRODUCTION: The impact of resident surgeon participation during vascular procedures on postoperative outcomes is incompletely understood. We characterized resident physician participation during carotid endarterectomy (CEA) procedures within the 2005-2009 American College of Surgeons National Surgical Quality Improvement Participant Use Datafile and evaluated associations with procedural characteristics and perioperative adverse events. METHODS: CEAs were identified using primary current procedural terminology codes; those performed simultaneously with other major procedures or unknown resident participation status were excluded. Group-wise comparisons based on resident participation status were performed using χ(2) or Fisher's exact test for categorical variables and t tests or nonparametric methods for continuous variables. Associations with perioperative adverse events (major = stroke, death, myocardial infarction, or cardiac arrest; minor = peripheral nerve injury, bleeding requiring transfusion, surgical site infection, or wound disruption) were assessed using multivariable logistic regression models adjusting for other known risk factors. RESULTS: A total of 25,280 CEA procedures were analyzed, of which residents participated in 13,705 (54.2%), while residents were absent in 11,575 (45.8%). Among CEAs with resident physician participation, resident level was categorized as junior (postgraduate year [PGY] 1-2) in 21.9%, senior (PGY 3-5) in 52.7%, and fellow (PGY ≥6) in 25.3%. Major adverse event rates with and without resident participation were 1.9% versus 2.1%, and minor adverse event rates with and without resident participation were 0.9% versus 1.0%, respectively. In multivariable models, resident physician participation was not associated with perioperative risk for major adverse events (odds ratio [OR], 0.90; 95% confidence interval [CI], 0.75-1.08) or minor adverse events (OR, 0.93; 95% CI, 0.72-1.21). CONCLUSIONS: Resident surgeon participation during CEA is not associated with risk of adverse perioperative events.