Faculty Bibliography

Objective: The two feared complications of pelvic flow disruption include buttock ischemia and mesenteric ischemia. In cases of extensive aortic coverage, spinal cord ischemia is also a risk. Unilateral or bilateral hypogastric artery flow interruption, either from atherosclerosis or intentionally, is considered problematic in endovascular repair and has not been well studied in open abdominal aortic aneurysm repair (OAR). We examined the effect of the interruption of flow to one or both hypogastric arteries on the outcomes after OAR.
Method(s): The Society for Vascular Surgery Quality Initiative database was queried for all patients who had undergone elective OAR between 2003 and 2020. All patients who had undergone elective OAR were included. Patients with data on their hypogastric arteries were stratified into two groups-patent bilaterally (normal pelvic perfusion) and unilateral or bilateral occlusion or ligation (compromised pelvic perfusion [CPP]). The primary endpoints were 30-day major morbidity (myocardial infarction, respiratory complications, renal injury, and lower extremity or intestinal ischemia) and mortality.
Result(s): During the study period, 9492 patients underwent elective OAR-860 (9.1%) with CPP and 8632 (90.9%) with patent bilateral hypogastric arteries. The two groups had similar cardiac risk factors, including a history of coronary artery disease, prior coronary intervention, and the use of P2Y12 inhibitors and statins (Table I). Most patients in the CPP cohort had concurrent iliac aneurysms (63.3% vs 24.8%; P <.001). Perioperative mortality was significantly higher in the CPP group (5.5% vs 3.1%; P <.001). Bilateral flow interruption resulted in greater perioperative mortality compared with unilateral interruption (7.1% vs 4.7%; P <.001). The CPP group also had increased rates of myocardial injury (6.7% vs 4.7%; P =.012), renal complications (18.9% vs 15.9%; P =.024), leg ischemia (3.5% vs 2.1%; P =.008), and bowel ischemia (5.7% vs 3.4%; P <.001). On multivariable analysis, CPP was associated with increased perioperative mortality (odds ratio, 1.47; 95% confidence interval, 1.14-1.88; P =.003). Intraoperative blood transfusion, chronic obstructive pulmonary disease, and renal insufficiency were other factors associated with perioperative mortality (Table II).
Conclusion(s): CPP is associated with increased perioperative complications and higher mortality in patients undergoing OAR. Hypogastric artery occlusion or the need to ligate these vessels likely signifies the presence of more complex disease. Careful technique and appropriate patient selection are critical in this cohort of patients. Furthermore, the differences in physiology of pelvic circulation in open and endovascular repair warrant further examination. [Formula presented] [Formula presented]
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Objective: The ability to independently ambulate reflects a patient's underlying functional status, which has been shown to be associated with the postoperative outcomes. We used the Vascular Quality Initiative to characterize (1) the proportion of patients who could not independently ambulate and (2) its subsequent association with outcomes after open abdominal aortic aneurysm (AAA) repairs.
Method(s): We identified all patients who had undergone elective or urgent open AAA repairs from January 2013 to August 2019 in the VQI registry. We recorded the demographic variables, comorbidities, and operative factors such as approach, operative ischemia time, proximal clamp site, and presence of iliac aneurysms. The short- and long-term outcomes included 30-day mortality, perioperative complications, failure to rescue (defined as death after a complication), and 1-year all-cause mortality. We dichotomized patients into functional vs non-functional status by their ability to independently ambulate and used both multivariable logistic regression and Cox proportional hazards models to evaluate the outcomes.
Result(s): Of the 5374 patients, 331 (6.2%) could not ambulate independently and were more likely to be older (median age, 69 vs 72 years) and female (25% vs. 38%) and to have more comorbidities. The overall outcomes were 4.3% for 30-day mortality, 38.7% for complications, 10.2% for failure to rescue, and 6.9% for 1-year mortality. Univariate analysis showed higher rates of all adverse outcomes for the patients who could not independently ambulate. On adjusted analysis, nonfunctional patients had increased odds of complications by 44% (odds ratio [OR], 1.44; 95% confidence interval [CI], 1.10-1.89) and 1-year mortality by 49% (OR, 1.49; 95% CI, 1.09-2.03) but not failure to rescue (OR, 1.04; 95% CI, 0.67-1.61) or 30-day mortality (OR, 1.21; 95% CI, 0.81-1.80). Increased hospital volume, age, and increased operative renal ischemia time were independently associated with adverse outcomes.
Conclusion(s): Patients who could not independently ambulate represent a small proportion of those undergoing open AAA repair but were associated with higher rates of postoperative complications and 1-year mortality. For patients with poor functional capacity and ambulatory function, whose anatomy precludes them from undergoing endovascular repair, we would recommend a nonoperative approach unless surgery is strongly indicated.
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Objective: Data regarding the effect of bilateral internal iliac artery (IIA) occlusion during endovascular abdominal aortic aneurysm repair (EVAR) are conflicting, with reported varied risks of pelvic and gastrointestinal ischemia. The aim of our study was to report the perioperative and long-term outcomes of IIA occlusion with origin graft coverage in patients undergoing elective EVAR.
Method(s): Using the Vascular Quality Initiative database (2010-2020), we retrospectively identified patients who had undergone EVAR for infrarenal abdominal aortic aneurysms and aortoiliac aneurysms with or without IIA occlusion by graft coverage or coils. The patients were stratified into three groups according to IIA occlusion status (none, unilateral, bilateral). The baseline characteristics, procedural details, in-hospital outcomes, and overall survival at 5 years were reviewed. The primary outcomes were in-hospital mortality and complications. The secondary outcomes included 5-year mortality. Cox proportional hazards models were used to determine the predictive factors of perioperative and 2-year mortality.
Result(s): A total of 26,690 patients were identified (mean age, 73.5 years; 82% male) who had undergone elective EVAR with bifurcated endografts. Of the 26,690 patients, 2195 (8.2%) had undergone adjunctive unilateral IIA origin graft occlusion, 523 (2%) had undergone bilateral IIA origin graft occlusion, and 23,970 (89.8%) had not undergone any IIA graft occlusion. Perioperatively, no statistically significant differences were found in the incidence of death (0.4% vs 0.6% vs 0.4%; P =.2), gastrointestinal ischemia (0.1% vs 0.1% vs 0.2%; P =.888), unplanned reoperation (1.5% vs 1.8% vs 2.3%; P =.181), or cardiopulmonary complications (2.5% vs 2.8% vs 3.4%; P =.247) among those with no, unilateral, and bilateral IIA origin graft occlusion, respectively (Table). The Kaplan-Meier estimate demonstrated comparable overall survival at 5 years (none, 86.7%; unilateral, 85.2%; bilateral, 89.4%; P =.133; Fig). On multivariable analysis, the status of IIA origin graft coverage was not associated with increased perioperative mortality or complications.
Conclusion(s): EVAR with bilateral IIA interruption was associated with favorable perioperative outcomes with a low rate of major complications. At the time of EVAR, unilateral and bilateral IIA occlusion with a stent-graft did not appear to confer additional risks of perioperative complications and mortality. Our results showed the safety of bilateral IIA interruption in patients undergoing elective EVAR for abdominal aortic aneurysms and aortoiliac aneurysms. [Formula presented] [Formula presented]
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Objectives: Although prior studies have provided mixed results with respect to the association between hospital volume and outcomes after open aortic surgeries, few have also accounted for surgeon volume. This study: (1) evaluated overall surgeon and hospital annual volumes for open aortic surgeries; and (2) assessed their association with postoperative outcomes.
Method(s): We queried the 2012 to 2019 Vascular Quality Initiative to identify all patients undergoing open abdominal aortic aneurysm repairs or aorto-iliac/femoral reconstructions for occlusive disease. We evaluated surgeon and hospital volumes using two categorizations, first by both quintiles of patients and then second by Leapfrog's Volume Expert Panel (surgeons: >=7/year, hospitals: >=10/year). Outcomes included 30-day mortality, overall complications, and failure-to-rescue (death after a major complication). For each outcome among elective or urgent repairs, we performed a multivariable logistic regression that adjusted for both surgeon and hospital volume, along with patient, clinical, and operative characteristics.
Result(s): We identified 15,666 patients, where 8619 (55%) had open abdominal aortic aneurysm repairs and 7047 (45%) had aorto-iliac/femoral bypasses, performed by 1283 surgeons across 250 hospitals. Median surgeon volumes were 2.0 cases/year (interquartile range [IQR], 1.0-3.3), and hospital volumes were 6.0 cases/year (IQR, 3.0-12.6). When adjusting for both surgeon and hospital volume quintiles, the lowest-volume surgeons (but not lowest-volume hospitals) were associated with worse outcomes relative to their counterparts: 30-day mortality (adjusted odds ratio [aOR], 1.56; 95% confidence interval [CI], 1.09-2.25), complications (aOR, 1.40; 95% CI, 1.15-1.71), and failure-to-rescue (aOR, 1.75; 95% CI, 1.15-2.64). When evaluating volume using Leapfrog criteria, only 65 surgeons (5.1%) met the volume guideline, performing 4197 open aortic surgeries (27%), whereas 84 hospitals (34%) met the volume guideline and performed 11,795 open aortic surgeries (75%). Again, surgeons (but not hospitals) who failed to meet Leapfrog volume criteria had higher adjusted odds of all three outcomes (Table): 30-day mortality (aOR, 1.47; 95% CI, 1.12-1.91), complications (aOR, 1.24; 95% CI, 1.07-1.42), and failure-to-rescue (aOR, 1.59; 95% CI, 1.13-2.22).
Conclusion(s): There exists marked nationwide variation in both surgeon and hospital volumes of open aortic cases, with surgeon volume having a greater association with postoperative outcomes relative to hospital volumes. Evidence-based volume thresholds and efforts to centralize open aortic surgery should incorporate surgeon volume in addition to hospital volume. [Formula presented]
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Objective: Although endovascular repairs of abdominal aortic aneurysms (AAAs) can be performed under less-invasive modes of anesthesia, such as moderate sedation with local anesthesia, open repair of AAAs always requires general anesthesia. Accordingly, patients' underlying pulmonary function will further affect their postoperative outcomes. We evaluated the association between the extent of a patient's chronic obstructive pulmonary disease (COPD) status and outcomes after open AAA repairs in a clinically robust registry.
Method(s): We identified all patients who had undergone open elective or urgent repair of nonruptured infrarenal and juxtarenal AAAs in the Vascular Quality Initiative registry from 2013 to 2019. We categorized COPD status into three groups: requiring no medications, requiring medications, and requiring supplemental oxygen. The primary outcomes included delayed extubation (>=24 hours after surgery) and postoperative pneumonia. The secondary outcomes included 30-day mortality and 1-year mortality. Multivariable logistic regression and Cox proportional hazards models were used to evaluate these outcomes after accounting for patient demographics, preoperative medications, intraoperative factors (i.e., proximal clamp site, visceral or renal ischemia time, retroperitoneal vs transabdominal approach), and hospital volume.
Result(s): We identified 6058 patients who had undergone open AAA repair (median age, 70 years; 74% male, 5% African American). One half of all the patients had had infrarenal proximal clamp sites (51%), followed by clamp sites above a single renal artery (15%), suprarenal clamping (26%), and supraceliac clamping (7.2%). One third of all patients had COPD (33%), including 12% requiring no medications, 19% taking medications, and 2.2% requiring home supplemental oxygen. The rates for the primary and secondary outcomes were delayed extubation, 11%; pneumonia, 11%; 30-day mortality, 4.4%; and 1-year mortality, 7.2%). After adjustment, an increasing adverse association was present stratified by underlying preoperative severity of COPD (Table) among all four outcomes.
Conclusion(s): We found a linear relationship between patient preoperative COPD status and outcomes among patients undergoing open AAA repairs. Specifically, patients with COPD who required medication had greater rates of prolonged extubation and pneumonia, and those requiring supplemental oxygen also experienced higher rates of 1-year mortality. We would argue that patients requiring supplemental oxygen at baseline should undergo nonoperative management unless strong indications for repair exist. [Formula presented]
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Objectives: In patients with carotid stenosis, both the severity of the stenosis as well as the plaque morphology influence the likelihood of future transient ischemic attack or stroke. In general, severely stenotic lesions are presumed to have a higher embolic potential than moderately stenotic lesions. Carotid intervention is indicated in patients with both moderate and severe stenosis with related cerebrovascular symptoms. However, the effect of the degree of carotid stenosis in symptomatic patients upon the outcome of carotid intervention has not been extensively studied.
Method(s): The Society for Vascular Surgery Quality Initiative database was queried for all patients undergoing transfemoral carotid stenting (CAS), carotid endarterectomy (CEA), and transcervical carotid stenting (TCAR) between 2003 and 2020. Patients undergoing interventions for symptomatic disease were included in the analysis. Patients were stratified into two cohorts based on the severity of stenosis-moderate (0%-69%) and severe (greater than or equal to 70%). Primary endpoints were perioperative neurologic events (strokes and transient ischemic attacks [TIAs]). Secondary endpoints were perioperative mortality and postoperative complications.
Result(s): Over 50,000 patients were included in the analysis: 5296 patients (8.9%) underwent TCAR, 7844 (13.3%) underwent CAS, and 45,853 (77.8%) underwent CEA for symptomatic carotid artery disease. In the TCAR and CEA cohorts, patients with moderate stenosis had a significantly higher rate of perioperative neurologic events than patients with severe stenosis (TCAR 4.3% vs 3.0%; P =.033; CEA 3.0% vs 2.3%; P <.001). In contrast, in patients undergoing CAS, there was no significant difference noted in the perioperative neurologic event rate (3.5% in moderate stenosis group vs 3.8% in severe stenosis group; P =.518). There were no differences in perioperative myocardial infarction or mortality (Table). On multivariable analysis, moderate stenosis was significantly and independently associated with an increased rate of neurologic events in the TCAR (odds ratio [OR], 0.833; 95% confidence interval, 0.693-1.000; P =.05), and CEA (odds ratio, 0.901; 95% confidence interval, 0.861-0.944; P <.001) cohorts.
Conclusion(s): Moderate carotid stenosis was associated with increased perioperative neurologic events in patients undergoing TCAR and CEA, but not CAS. Therefore, this effect was noted only in the cohorts that require direct open surgical manipulation of the cervical carotid artery (TCAR and CEA). Moderately stenotic lesions that become symptomatic likely have worse intrinsic plaque morphology than severely stenotic lesions, producing cerebrovascular symptoms at a lower degree of stenosis. The mechanism of such events warrants further evaluation with a particular focus on plaque morphology and brain physiology. [Formula presented]
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OBJECTIVE:Previous studies evaluating the association between abdominal aortic aneurysm (AAA) size with postoperative outcomes after open repairs seldom accounted for renal or visceral artery involvement, proximal clamp site, intraoperative renal ischemia time, and hospital volume. This study examined the association between aneurysm size with outcomes after open repairs. METHODS:We identified patients who underwent open repairs of infrarenal versus juxtarenal nonruptured AAAs, defined by proximal clamp site, in the 2004-2019 Vascular Quality Initiative. Outcomes included 30-day mortality, postoperative complications, failure to rescue, and 1-year mortality. Multivariable logistic regressions adjusted for patient characteristics, operative factors, hospital volume, and hospital clustering. RESULTS:We identified 8011 patients (54% infrarenal, 46% juxtarenal). The median aneurysm size did not differ between infrarenal versus juxtarenal aneurysms (5.7 cm vs 5.9 cm; P = .12). For infrarenal aneurysms, every 1-cm increase in size increase the adjusted odds ratio (OR) or hazard ratio (HR) of 30-day mortality by 18% (OR, 1.18; 95% CI, 1.06-1.31), failure to rescue by 20% (OR, 1.20; 95% CI, 1.06-1.34), 1-year mortality by 18% (HR, 1.18; 95% CI, 1.10-1.26), but not complications (OR, 1.03; 95% CI, 0.98-1.07). For juxtarenal aneurysm, larger aneurysm sizes were not associated with any outcome. Proximal clamp site, ischemia time, and volume were associated with outcomes. CONCLUSIONS:The association between AAA size and outcomes matters less with renal and visceral artery aneurysmal involvement, having important implications for surgical decision-making, operative planning, and patient counseling.

BACKGROUND:Autologous vein is considered the preferred conduit for lower extremity bypass. There is, however, limited literature regarding conduit choice for open popliteal artery aneurysm (PAA) repair. We sought to compare outcomes of PAA repair using vein versus prosthetic conduits. METHODS:The Vascular Quality Initiative database (2003-2019) was queried for patients with PAAs undergoing elective conventional revascularization originating from the superficial femoral and popliteal arteries. Conduits were categorized as vein or prosthetic. Primary outcomes were primary graft patency, freedom from major adverse limb event (MALE) and MALE-free survival at 2-years. Kaplan-Meier method with log-rank tests was used for estimation and comparison of patency. RESULTS:A total of 1,146 limbs in 1,065 patients underwent elective open revascularization for popliteal artery aneurysm. Vein was used in 921 limbs (80%), and prosthetic in 225 (20%). Patients in the prosthetic cohort had a shorter procedure time, were older, and had a higher prevalence of COPD. Postoperatively, prosthetic patients were more likely to be started and maintained on anticoagulation without increased incidence of hematoma. There was no significant difference in the rate of surgical site infection (2% vs. 2%; P = .946). There was an increased tendency toward more symptomatic patients in the vein cohort although not statistically significant (49% vein vs. 41% prosthetic; P = .096). On a mean follow-up of 13 ± 5 months, the incidence of MALE and MALE-free survival were comparable between the two groups. The 2-year primary and secondary patency rates were similar, 87% and 96% in the vein, and 91% and 95% in the prosthetic groups, respectively. At multivariable analysis, outflow bypass targets to the infrapopliteal arteries (HR 2.05; 95% confidence interval (CI), 1.16-3.65; P = .014) and symptomatic aneurysm (HR 1.81; 95% CI, 1.04-3.15; P = .037) were independently associated with loss of primary patency. Conduit type did not make a difference in MALE-free survival, or primary graft patency at 2-years. CONCLUSIONS:Our study demonstrates that conventional open PAA repair with prosthetic conduit yields results comparable to those with vein conduit with regard to primary and secondary patency and major adverse limb events at 2-years for targets to the popliteal artery. However, when the distal target was infrapopliteal, worse outcomes were observed with prosthetic conduit. Our results suggest that vein conduit should be preferentially used for infrapopliteal targets, while prosthetic conduit confers comparable outcomes in a subset of patients who do not have suitable autologous vein conduits.

INTRODUCTION/BACKGROUND:The natural history of penetrating aortic ulcers (PAU) and intramural hematomas (IMH) of the aorta is not well described. While repair is warranted for rupture, unremitting chest pain or growth, there is no established threshold for treating incidental findings. Thoracic endovascular aortic repair (TEVAR) offers an attractive approach in treating these pathologies, however, peri-procedural and post-operative outcomes are not well defined. METHODS:Patients 18 or older identified in the VQI database who underwent TEVAR for PAU and/or IMH between 1/2011-2/2020 were included. We identified 1042 patients, of whom 809 had available follow-up data. Patient demographics and comorbidities were analyzed to identify risk factors for major adverse events (MAE), as well as postoperative and late mortality. RESULTS:The cohort was 54.8% female and 69.9% former smokers with a mean age of 71.1 years. Comorbidities were prevalent with 57.8% classified ASA IV; 89.8% had hypertension, 28.3% chronic obstructive pulmonary disease (COPD), 17.9% coronary artery disease, and 12.2% congestive heart failure (CHF). Patients were predominately symptomatic (74%) and 44.5% underwent non-elective repair. MAE incidence was 17%. Independent predictors of MAE were history of CAD, non-Caucasian race, emergent procedural indication, ruptured presentation, and deployment of two or more endografts. In-hospital mortality was 4.3%. Seventy-three percent of index hospitalization mortalities were treatment-related. Of 809 patients with follow-up (mean 25.1 months±19 months), all-cause mortality was 10.6%. Predictors of late mortality in follow-up included age greater than 70 years, ruptured presentation, and history of COPD and ESRD. Subset analysis comparing symptomatic (74%) vs. asymptomatic (26%) patients demonstrated the former were frequently female (58.2% vs. 45.3%, p<.001) with a higher incidence of MAE (20.6% vs. 6.9%, p<.001), notably higher in-hospital reintervention rates (5.9% vs. 1.5%, p=.002) and mortality (5.6% vs. 0.7%, log-rank p=.015), and prolonged length of stay (6.9 vs. 3.7 days, p<.0001) despite similar procedural risks. In follow-up, late mortality was higher in the symptomatic cohort (12.2% vs. 6.5%, log-rank p=.025), with all treatment-related mortalities limited to the symptomatic group. CONCLUSIONS:We demonstrate significantly higher morbidity and mortality in symptomatic patients undergoing repair compared to asymptomatic patients, despite similar baseline characteristics. Asymptomatic patients treated with TEVAR had no treatment-related mortality in follow-up, with overall prognosis largely dependent on pre-existing comorbidities. These findings, in conjunction with growing evidence highlighting the risk of disease progression and attendant morbidity associated with these aortic entities, suggest a need for natural history studies and definitive guidelines on the elective repair of IMH and PAU.

BACKGROUND:Intensive care unit (ICU) admission after endovascular aortic aneurysm repair (EVAR) varies across medical centers. We evaluated the association of postoperative ICU utilization with perioperative and long-term outcomes after EVAR. STUDY DESIGN/METHODS:The Vascular Quality Initiative (2003-2019) was queried for index elective EVARs. Included centers were categorized by percentage of EVARs postoperatively admitted to the ICU; routine ICU (rICU) centers as ≥80% ICU admissions and non-routine ICU (nrICU) centers as ≤20% ICU admissions. Patients admitted preoperatively or with same day discharge were excluded. Perioperative outcomes and survival were compared between rICU and nrICU centers. RESULTS:Of 45,310 EVARs in the database, 35,617 were performed at rICU or nrICU centers - 5,443 (15.3%) at 71 rICU centers and 30,174 (84.7%) at 200 nrICU centers. Overall, mean age was 73.4 years and 81.6% were male. Postoperative myocardial infarction, pulmonary complications, stroke, leg ischemia, and in-hospital mortality were similar between rICU and nrICU centers (all P>.05). Postoperative length of stay (LOS) was prolonged at rICU centers (mean) (2.2±3.6 vs. 2±4.2 days, P<.001). 1-year survival was similar between rICU and nrICU centers, respectively, (94.9% vs. 95.4%, P=.085). When compared to nrICU centers, rICU centers had similar 1-year mortality risk (HR 1.15, 95% CI .99-1.34, P=.076), but were associated with longer postoperative LOS (MR 1.1, 95% CI 1.08-1.13, P<.001). CONCLUSION/CONCLUSIONS:Routine ICU utilization after EVAR was associated with prolonged postoperative LOS without improved perioperative/long-term morbidity or mortality. Updated care pathways to include postoperative admission to lower acuity care units may reduce costs without compromising care.