Definition and Perception of Autonomy in Vascular Surgery Training.

BACKGROUND: There is a lack of data evaluating operative autonomy within vascular surgery. This study aims to determine where discrepancies exist in the definition of autonomy between trainees and attending faculty. METHODS: An Institutional Review Board-approved, anonymous survey was e-mailed to vascular trainees and attending faculty at all Accreditation Council for Graduate Medical Education-approved vascular surgery training programs in the United States. Data were compared using chi-square statistical analysis. RESULTS: One-hundred forty-nine responses from vascular surgery trainees (n = 89) and faculty (n = 60) were obtained. The most highly ranked preoperative skill by trainees was Case Planning, at all post-graduate year-levels. Although a majority of trainees believe this skill is expected of them, only 36.1% of attendings responded that they expect all trainee levels to perform this task. Draping/positioning was ranked as the second most important intraoperative task for all post-graduate year-levels by attendings; however, only 32.8% of attendings expect trainees to perform this. Exposure of Critical Structures was ranked as the most important intraoperative task by both trainees and attendings at the Chief and Fellow level. However, responses by both trainees and attendings showed that this is expected <70% of the time. When asked about double-scrubbing independently of other tasks, most trainees assessed double-scrubbing as inherently important to autonomy at all levels of training and within all regions. Only 44.3% of attendings responded that they expect all trainees to double-scrub. Additionally, most trainees in all regions responded that they spend <25% of cases double-scrubbed. CONCLUSIONS: These responses show a discrepancy between the skills that both trainees and attendings deem important to autonomy versus what is being expected of trainees in reality.

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.

Hypogastric Artery Flow Interruption is Associated with Increased Mortality After Open Aortic Repair.

BACKGROUND: Potential complications of pelvic flow disruption during aortic aneurysm repair include buttock ischemia and mesenteric ischemia. Unilateral or bilateral hypogastric artery flow interruption, either from atherosclerosis or intentionally to facilitate aneurysm repair, is considered problematic in endovascular repair; however, it has not been well studied in open abdominal aortic aneurysm (AAA) repair (OAR). We sought to examine the effect of interruption of flow to one or both hypogastric arteries on outcomes after OAR. METHODS: The Society for Vascular Surgery Quality Initiative database was queried for all patients undergoing elective open AAA repair between 2003 and 2020. (redundant) Patients with appropriate data on their hypogastric arteries postoperatively were stratified into two groups-patent bilaterally (normal pelvic perfusion, NPP) and unilateral or bilateral occlusion or ligation (compromised pelvic perfusion, CPP). Primary endpoints were 30-day major morbidity (myocardial infarction, respiratory complications, renal injury, and lower extremity or intestinal ischemia) and mortality. RESULTS: During the study period, 9.492 patients underwent elective open AAA repair-860 (9.1%) with compromised pelvic perfusion and 8,632 (90.9%) with patent bilateral hypogastric arteries. The groups had similar cardiac risk factors, including a history of coronary artery disease, prior coronary intervention, and the use of P2Y12 inhibitors and statins. A majority of patients in the CPP cohort had concurrent iliac aneurysms (63.3% vs. 24.8%; P < 0.001). The perioperative mortality was significantly higher in patients with compromised pelvic perfusion (5.5% vs. 3.1%; P < 0.001). Bilateral flow interruption had a trend toward higher perioperative mortality compared to unilateral interruption (7.1% vs. 4.7%; P < 0.147). The CPP group also had increased rates of myocardial injury (6.7% vs. 4.7%; P = 0.012), renal complications (18.9% vs. 15.9%; P = 0.024), leg and bowel ischemia (3.5% vs. 2.1%; P = 0.008; and 5.7% vs. 3.4%; P < 0.001, respectively). On multivariable analysis, CPP was associated with increased perioperative mortality (OR 1.47, CI 1.14-1.88, P = 0.003). On Kaplan-Meier analysis, there was no difference in survival at 2 years postdischarge between the NPP and CPP cohorts (86.1% vs. 87.5%, log-rank P = 0.275). CONCLUSIONS: Compromised pelvic perfusion is associated with increased perioperative complications and higher mortality in patients undergoing OAR. The sequelae of losing pelvic perfusion, in addition to the presence of more complex atherosclerotic and aneurysmal disease resulting in more difficult dissection, likely contribute to these findings. Thus, patients considered for OAR who have occluded hypogastric arteries or aneurysmal involvement of the hypogastric artery preoperatively may be candidates for more conservative management beyond traditional size criteria.

Plaque contact surface area and lumen volume predict stroke risk in extracranial carotid artery stenosis.

BACKGROUND: The standard indication for intervention in asymptomatic disease is currently percent stenosis in the internal carotid artery as measured by the North American Symptomatic Carotid Endarterectomy Trial (NASCET) method, which remains limited in discriminating power. Computed tomography angiography (CTA) is widely used to calculate NASCET stenosis, but also offers the opportunity to analyze carotid artery plaques from a morphological perspective that has not been widely used. We aim to improve stroke risk stratification of patients with carotid artery stenosis using plaque three-dimensional (3D) modeling and image analysis. METHODS: Patients with computed tomography angiographies appropriate for 3D reconstruction were identified from a National Institutes of Health-designated stroke center database, and carotid arteries were segmented and analyzed using software algorithms to calculate contact surface area (CSA) between the plaque and blood flow, and volume of the flow lumen within the region of the plaque (lumen volume [LV]). These novel parameters factor in the 3D morphometry inherent to each carotid plaque and were compared between stroke and nonstroke groups. RESULTS: A total of 134 carotid arteries were analyzed, 33 of which were associated with an ipsilateral stroke. Plaques associated with stroke demonstrated statistically significant increases in average CSA (541.52 mm2) and LV (394.64 mm3) when compared with those not associated with stroke (371.18 mm2 and 245.92 mm3, respectively). When comparing area under the receiver operating characteristics curve between NASCET (0.65) percent stenosis, CSA (0.74), and LV (0.77), both CSA and LV demonstrated more favorable values in predicting stroke risk in patients with carotid stenosis. CONCLUSIONS: The data presented here demonstrate morphological features of carotid plaques that are independent of NASCET criteria stratification and may present an improved method in assessing stroke risk in patients with carotid artery stenosis.

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.

Use of a Reperfusion Cannula for Acute Limb Ischemia in a Patient with Carotid Artery Extracorporeal Membrane Oxygenation Cannulation.

Acute limb ischemia is a rare but potentially devastating event in a critically ill patient. In the pediatric population, limb ischemia is usually related to iatrogenic vascular damage and arterial thrombus formation secondary to arterial catheter placement. Children who have undergone femoral artery cannulation for venoarterial extracorporeal membrane oxygenation (VA-ECMO) are particularly at risk for this complication. In these cases, there have been reports of the successful use of a percutaneous limb reperfusion cannula to prevent or treat limb ischemia. We present a case of an 18 month old female who required VA-ECMO via carotid artery cannulation for viral myocarditis and subsequently developed acute lower limb ischemia related to a thrombus from an indwelling femoral arterial catheter in place for hemodynamic monitoring. This case highlights the usage of a distal reperfusion cannula and extracorporeal membrane oxygenation (ECMO) circuit for a novel purpose, which coupled with near infrared spectroscopy (NIRS) monitoring successfully re-established blood flow to the ischemic limb.

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.

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.

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 DTA is a physiologically impactful operation with relatively high rates of mortality, paraplegia, and renal failure. Thoracic endovascular aneurysm repair (TEVAR) has revolutionized the treatment of DTA, and has largely supplanted open repair due to lower morbidity and mortality. These Society for Vascular Surgery (SVS) Practice Guidelines are applicable to the use of TEVAR for descending thoracic aortic aneurysm (TAA) as well as other rarer pathologies of the DTA. Many of the strongest recommendations from the present guideline focus on imaging either prior to, during or after TEVAR.

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.

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.

The Safety and Efficacy of Extended TEVAR in Acute Type B Aortic Dissection.

BACKGROUND: Thoracic endovascular aortic repair (TEVAR) with endograft coverage from the left subclavian artery to the celiac artery has been hypothesized to increase spinal cord ischemia. This study analyzes the impact of extended coverage on adverse outcomes and aortic remodeling in patients with complicated acute type B aortic dissection (aTBAD). METHODS: From January 2012 to October 2018, 91 patients underwent TEVAR for aTBAD. Median follow-up was 3.1 (interquartile range, 1.2-4.9) years and was complete in 94% of patients. The extent of aortic endograft coverage was categorized as standard (n = 39) or extended (n = 52). Contrast-enhanced imaging scans were analyzed to determine length of coverage, maximum aortic diameters, and false lumen (FL) status. RESULTS: The mean age was 52.6 ± 13.9 years, and 66% were men. The most common indications for intervention were malperfusion (42%) and refractory pain (34%). Thirteen (14%) patients required a lumbar drain (preoperative: n = 3; postoperative: n = 10). Mean duration between scans was 2.0 ± 1.9 years. Length of aortic coverage was significantly longer in the extended group (241.7 ± 29.2 mm vs 180.8 ± 22.3 mm in the standard group; P < .001). In-hospital and overall mortality were 6% and 11%, respectively. There were no cases of paraplegia, and the incidence of spinal cord ischemia was 3%. After TEVAR, there was a higher incidence of FL obliteration or thrombosis at the distal descending thoracic aorta in the extended group (53% vs 16% in the standard group; P = .004). CONCLUSIONS: Extended TEVAR carries a low risk of spinal cord ischemia and improves FL remodeling of the descending thoracic aorta in patients with aTBAD. This strategy may decrease the need for reinterventions on the thoracic aorta in the chronic phase of TBAD.

Discharge to a Post-Acute Care Facility after Emergent Femoral Artery Repair is Not Protective Against Wound Complications.

BACKGROUND: Access site complication is the most common adverse event after endovascular intervention, and when emergent operative repair of the common femoral artery (CFA) is needed, patient morbidity can be significantly increased. The intent of this project was to identify predictors of wound events after emergent operative repair of the CFA due to an access site complication. It was hypothesized that patients discharged to a facility would benefit from an ongoing relationship with healthcare professionals as evidenced by more consistent follow-up and lower wound complication rates. METHODS: Patients who had a percutaneous CFA access complication and required emergent open CFA repair at an academic medical institution between 2015 and 2018 were included, and the charts were reviewed retrospectively. Primary outcomes included wound complication and outpatient compliance with vascular surgery clinic visit. Dichotomous groups were evaluated by the chi-squared test, and continuous variables were evaluated by Student's t-test. Univariate and multivariate regression analyses were completed to assess risk factors contributing to wound event or failure of clinic follow-up. RESULTS: Forty-four patients were identified with emergent CFA repair due to an access complication between July 2015 and June 2018. Among this population, 33% of patients had wound complications and 27% were discharged to a facility. Among those discharged to a facility, the rate of follow-up to the vascular surgeon's clinic was significantly lower than those discharged to home (40% vs. 85%, P < 0.05), and the incidence of wound complications appeared greater but did not reach statistical significance (50% vs. 27%, P = 0.11). Univariate analysis indicated that kidney disease, albumin <3 g/dL, and current smoking were predictive of wound complication, whereas on multivariate analysis, only kidney disease remained predictive (P < 0.05, odds ratio = 22). The modified frailty index (mFI) was not predictive of wound complications or compliance with follow-up. However, mFI did approach statistical significance when predicting discharge to a facility. CONCLUSIONS: Despite the availability of medical personnel to arrange transportation and provide wound care in post-acute care facilities, patients who were discharged to a facility after CFA injury requiring emergent repair experienced lower compliance with clinic follow-up and may have suffered more wound complications. Strategies to improve compliance with patient follow-up and wound healing in patients sent to post-acute care facilities are warranted.

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.

Intermediate fenestrations reduce flow reversal in a silicone model of Stanford Type B aortic dissection.

Pulsatile, three-dimensional hemodynamic forces influence thrombosis, and may dictate progression of aortic dissection. Intimal flap fenestration and blood pressure are clinically relevant variables in this pathology, yet their effects on dissection hemodynamics are poorly understood. The goal of this study was to characterize these effects on flow in dissection models to better guide interventions to prevent aneurysm formation and false lumen flow. Silicone models of aortic dissection with mobile intimal flap were fabricated based on patient images and installed in a flow loop with pulsatile flow. Flow fields were acquired via 4-dimensional flow MRI, allowing for quantification and visualization of relevant fluid mechanics. Pulsatile vortices and jet-like structures were observed at fenestrations immediately past the proximal entry tear. False lumen flow reversal was significantly reduced with the addition of fenestrations, from 19.2 ±â€¯3.3% in two-tear dissections to 4.67 ±â€¯1.5% and 4.87 ±â€¯1.7% with each subsequent fenestration. In contrast, increasing pressure did not cause appreciable differences in flow rates, flow reversal, and vortex formation. Increasing the number of intermediate tears decreased flow reversal as compared to two-tear dissection, which may prevent false lumen thrombosis, promoting persistent false lumen flow. Vortices were noted to result from transluminal fluid motion at distal tear sites, which may lead to degeneration of the opposing wall. Increasing pressure did not affect measured flow patterns, but may contribute to stress concentrations in the aortic wall. The functional and anatomic assessment of disease with 4D MRI may aid in stratifying patient risk in this population.

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.

The Impact of Thoracic Endovascular Aortic Repair on Long-Term Survival in Type B Aortic Dissection.

BACKGROUND: Currently, optimal medical therapy is first-line therapy for uncomplicated acute type B aortic dissection (aTBAD) despite poor long-term outcomes. This study examines the impact of thoracic endovascular aortic repair (TEVAR) in the acute and chronic phases on short-term and long-term survival of patients presenting with aTBAD. METHODS: A review of the Emory aortic database from 2000 to 2016 identified 398 patients diagnosed with aTBAD. At index hospitalization, complicated patients underwent TEVAR (aTEVAR [thoracic endovascular aortic repair in the acute phase], n = 80) and uncomplicated patients received optimal medical therapy (n = 318). Uncomplicated patients were divided into subgroups based on final treatment: (1) TEVAR (cTEVAR [thoracic endovascular aortic repair in the chronic phase], n = 87); (2) open aortic replacement (n = 59); and (3) optimal medical therapy (n = 172). Kaplan-Meier curves assessed long-term mortality. RESULTS: The mean age of patients was 57 ± 12 years. In the uncomplicated group, 146 patients (45.9%) patients failed optimal medical therapy and underwent open repair (n = 59) or endovascular repair (cTEVAR, n = 87) repair in the chronic phase. Inhospital mortality was 5% and equivalent between complicated and uncomplicated aTBAD groups at index hospitalization. For patients requiring intervention, mortality and renal failure were highest for open patients (16.9%, p < 0.01, and 10.2%, p = 0.05, respectively), and stroke was highest among aTEVAR patients (7.5%, p < 0.01). The incidence of paraparesis and paraplegia was low and equivalent among the three groups. Despite a higher mortality risk at presentation, there was a trend toward improved long-term survival among complicated aTBAD patients (complicated 84.1% versus uncomplicated 58.9%, p = 0.17). Intervention-free survival at 5 and 10 years for all uncomplicated patients was 50.4% and 32.9%, respectively. CONCLUSIONS: The treatment of uncomplicated aTBAD with optimal medical therapy results in a high incidence of surgical intervention and poor long-term survival. At the index hospitalization, TEVAR may confer a survival advantage and serve as optimal therapy for complicated and uncomplicated aTBAD patients.

Pulsatile Flow Leads to Intimal Flap Motion and Flow Reversal in an In Vitro Model of Type B Aortic Dissection.

Understanding of the hemodynamics of Type B aortic dissection may improve outcomes by informing upon patient selection, device design, and deployment strategies. This project characterized changes to aortic hemodynamics as the result of dissection. We hypothesized that dissection would lead to elevated flow reversal and disrupted pulsatile flow patterns in the aorta that can be detected and quantified by non-invasive magnetic resonance imaging. Flexible, anatomic models of both normal aorta and dissected aorta, with a mobile intimal flap containing entry and exit tears, were perfused with a physiologic pulsatile waveform. Four-dimensional phase contrast magnetic resonance (4D PCMR) imaging was used to measure the hemodynamics. These images were processed to quantify pulsatile fluid velocities, flow rate, and flow reversal. Four-dimensional flow imaging in the dissected aorta revealed pockets of reverse flow and vortices primarily in the false lumen. The dissected aorta exhibited significantly greater flow reversal in the proximal-to-mid dissection as compared to normal (21.1 ± 3.8 vs. 1.98 ± 0.4%, p < 0.001). Pulsatility induced unsteady vortices and a pumping motion of the distal intimal flap corresponding to flow reversal. Summed true and false lumen flow rates in dissected models (4.0 ± 2.0 L/min) equaled normal flow rates (3.8 ± 0.1 L/min, p > 0.05), validated against external flow measurement. Pulsatile aortic hemodynamics in the presence of an anatomic, elastic dissection differed significantly from those of both steady flow through a dissection and pulsatile flow through a normal aorta. New hemodynamic features including flow reversal, large exit tear vortices, and pumping action of the mobile intimal flap, were observed. False lumen flow reversal would possess a time-averaged velocity close to stagnation, which may induce future thrombosis. Focal vortices may identify the location of tears that could be covered with a stent-graft. Future correlation of hemodynamics with outcomes may indicate which patients require earlier intervention.

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.