Faculty Bibliography

BACKGROUND:A nationwide variation in mortality stratified by hospital volume exists after open repair of complex abdominal aortic aneurysms (AAAs). In the present study, we assessed whether the rates of postoperative complications or failure-to-rescue (defined as death after a major postoperative complication) would better explain the lower mortality rates among higher volume hospitals. METHODS:Using the 2004 to 2018 Vascular Quality Initiative database, we identified all patients who had undergone open repair of elective or symptomatic AAAs, in which the proximal clamp sites were at least above one renal artery. We divided the patients into hospital quintiles according to the annual hospital volume and compared the risk-adjusted outcomes. Multivariable logistic regression, adjusted for patient characteristics, operative factors, and hospital volume, was used to evaluate three outcomes: 30-day mortality, overall complications, and failure-to-rescue. RESULTS:We identified 3566 patients who had undergone open repair of elective or symptomatic complex AAAs (median age, 71 years; 29% women; 4.1% black; 48% Medicare insurance). The unadjusted rates of 30-day postoperative mortality, overall complications, and failure-to-rescue were 5.0%, 44%, and 10%, respectively. Common complications included renal dysfunction (25%), cardiac dysrhythmia (14%), and pneumonia (14%), with the specific failure-to-rescue rate ranging from 12% to 22%. On adjusted analysis, the risk-adjusted mortality rate was 2.5 times greater for the lower volume hospitals relative to the higher volume hospitals (7.4% vs 3.0%; P < .01). Although the risk-adjusted complication rates were similar between these hospital groups (30% vs 27%; P = .06), the failure-to-rescue rate was 2.3 times greater for the lower volume hospitals relative to the higher volume hospitals (6.3% vs 2.7%; P = .02). CONCLUSIONS:Higher volume hospitals had lower mortality rates after open repair of complex AAAs because they were better at the "rescue" of patients after the occurrence of postoperative complications. Both an understanding of the clinical mechanisms underlying this association and the regionalization of open repair might improve patient outcomes.

Objective: Type II endoleaks (T2E), commonly identified after EVAR, are associated with late endograft failure and secondary rupture. Quantity and size of aortic aneurysm sac outflow vessels (AASOV), namely the inferior mesenteric, lumbar, and accessory renal arteries, have been implicated as known risk factors for persistent T2E. Given technical difficulties associated with post-EVAR embolization, prophylactic coil embolization of AASOV-related T2E has been advocated to prevent retrograde T2E; however, current evidence is limited. We sought to examine the effect of concomitant prophylactic AASOV coil embolization in patients undergoing EVAR.
Method(s): Patients 18 and older in the Society for Vascular Surgery Vascular Quality Initiative database who underwent elective EVAR for intact aneurysms between January 2009 and November 2020 were included. Patients with a history of prior aortic repair and those without available follow-up data were excluded. Patient demographics, operative characteristics, and outcomes were analyzed by group: EVAR with or without prophylactic AASOV embolization (emboEVAR). Primary outcomes of interest were rates of in-hospital postoperative complications, incidence of aneurysmal sac regression (>=5 mm), and rates of reintervention in follow-up.
Result(s): A total of 15,060 patients were included: 272 had emboEVAR and 14,788 had EVAR alone. There was no significant difference between groups in terms of age, comorbidities, or anatomic characteristics including mean maximum preoperative aortic diameter (5.5 vs 5.6 cm, P =.48) (Table I). emboEVAR was associated with significantly longer procedural times (148 vs 124 minutes, P <.0001), prolonged fluoroscopy (32 vs 23 minutes, P <.0001), increased contrast use (105 vs 91 mL, P <.0001), without significant reduction in T2E at completion (17.7% vs 16.3%, P =.54). Incidences of postoperative complications (3.7% vs 4.6%, P =.56), index hospitalization reintervention rates (0.7% vs 1.3%, P =.59), length of stay (1.8 vs 2 days, P =.75), and 30-day mortality (0% vs 0%, P = 1) were similar between groups. In mid-term follow-up (14.6 +/- 6.2 months), the emboEVAR group had a significant mean reduction in maximum aortic diameter (0.69 vs 0.54 cm, P =.006) with a higher proportion experiencing sac regression >=5 mm (53.5% vs 48.7%) and reintervention rates were similar between groups. On multivariate analysis, prophylactic AASOV (odds ratio: 1.34, confidence interval: 1.04-1.74, P =.024) was a significant independent predictor of sac regression (Table II).
Conclusion(s): Prophylactic AASOV embolization can be performed safely for patients with intact aortic aneurysms undergoing elective EVAR without significant associated perioperative morbidity or mortality. emboEVAR is associated with significant sac regression compared with EVAR alone in mid-term follow-up. This technique shows promise and future efforts should focus on elucidating the role of concomitant selective vs complete prophylactic AASOV embolization in patients undergoing EVAR. [Formula presented] [Formula presented]
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Objective: Although beta-blocker (BB) use is routine for type B aortic dissections (TBADs), its effect in patients undergoing thoracic endovascular aortic repair (TEVAR) is unclear. Furthermore, the effect of BB use on the perioperative outcomes after TEVAR has not been evaluated. We evaluated the effect of BB use on the perioperative outcomes in patients with TBAD undergoing TEVAR.
Method(s): The Society for Vascular Surgery Vascular Quality Initiative database was queried for all patients who had undergone TEVAR for TBAD between September 2012 and February 2020. BB use was defined as the use of such medications for >=30 days preoperatively. Patients were dichotomized according to preoperative BB use (no-BB and BB cohorts). The patient characteristics, procedural details, and postoperative outcomes were compared. The primary endpoints were 30-day mortality and overall postoperative complications, including myocardial infarction, new dysrhythmia, congestive heart failure, access site complications, respiratory, cerebrovascular symptoms, and arm, leg, renal, spinal cord, and gastrointestinal ischemia requiring surgical intervention.
Result(s): Of 2283 patients undergoing TEVAR for TBAD, 1130 (49%) were receiving a BB preoperatively. The BB cohort was older with greater proportions of hypertension, coronary artery disease, congestive heart failure, diabetes, chronic kidney disease, and end-stage renal disease (Table I). Additionally, the BB cohort were more likely to be taking aspirin, a P2Y12 antagonist, a statin, or an ACE inhibitor, and/or receiving anticoagulation therapy preoperatively. The non-BB cohort had more nonelective, symptomatic, and acute dissections. The procedural details, including rates of open conversion and general anesthesia, estimated blood loss, transfusion requirements, and operative times were comparable. On univariate analysis, the BB cohort had a lower risk of overall postoperative complications (22% vs 33%; P <.001) and mortality (4.7% vs 7.7%; P =.003) compared with the non-BB cohort. On multivariable analysis, BB use was associated with a 22% reduction in the odds of postoperative complications (odds ratio, 0.78; 95% confidence interval, 0.62-0.99; P =.044) but did not influence mortality (odds ratio, 1.14; 95% confidence interval, 0.73-1.71; P =.562; Table II).
Conclusion(s): BB use was associated with a significant reduction in postoperative complications for patients undergoing TEVAR for TBAD. Therefore, BB use should be strongly encouraged for appropriately selected patients undergoing TEVAR. [Formula presented] [Formula presented]
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Objective: There is a paucity of data evaluating outcomes of lower extremity bypass (LEB) using suprainguinal inflow for infrainguinal vessels. The purpose of this study is to report outcomes after LEB originating from aortoiliac arteries to infrafemoral targets.
Method(s): The Vascular Quality Initiative database (2003-2020) was queried for patients undergoing LEB originating from the aortoiliac arteries and to the popliteal and tibial arteries. Patients were stratified into three cohorts based on outflow targets (above-knee popliteal, below-knee popliteal and tibial arteries). Perioperative and 1-year outcomes including primary patency, amputation-free survival, and major adverse limb events (MALEs) were compared, and the Cox proportional hazards model was used to estimate the independent prognostic factors of outcomes.
Result(s): Of 403 LEBs, 389 (96.5%) originated from the external iliac artery, whereas the remaining from the aorta and common iliac artery. A total of 116 (28.8%), 151 (27.5%), and 136 (43.7%) were to the above-knee popliteal, below-knee popliteal, and tibial arteries, respectively (Table). In total, 194 (48%) and 186 (46%) patients had prior ipsilateral LEB and percutaneous vascular interventions, respectively. Below-knee popliteal and tibial bypasses were performed more frequently in patients with chronic limb-threatening ischemia (70% and 70% vs 48%; P <.001). Vein conduit was more often used for tibial bypass than for above- and below-knee popliteal bypasses (46% vs 22% and 17%; P <.001). In the perioperative period, below-knee popliteal and tibial bypass patients had higher reoperation rates (17% and 14% vs 5%; P =.015) and lower primary patency (91% and 90% vs 96%; P =.044) than above-knee bypass patients. Perioperative pulmonary complication and mortality rates were similar among the cohorts. At 1 year, compared with above-knee popliteal bypasses, below-knee and tibial bypasses demonstrated lower primary patency (60.9% and 62.3% vs 83.3%; P <.001; Fig) and amputation-free survival (69.1% and 66.4% vs 79.4%; P =.0223), but freedom from MALEs were similar (87.2% and 82.8% vs 90.9%; P =.0585). On multivariable analysis, compared with above-knee popliteal bypasses, tibial bypasses were independently associated with increased loss of primary patency (hazard ratio, 1.9; 95% confidence interval, 1.03-3.51; P =.039), but with similar major ipsilateral amputation/death and MALEs.
Conclusion(s): Compared with those using historic infrainguinal inflow, LEBs with suprainguinal inflow appear to have accepTable rates of 1-year patency and limb salvage in patients at high risk of bypass failure. Tibial outflow target was independently associated with worse primary patency. [Formula presented] [Formula presented]
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Objective: Endovascular abdominal aortic aneurysm repair (EVAR) for patients with chronic obstructive pulmonary disease (COPD) has been associated with improved outcomes compared with open repair. However, the effects of COPD severity on the outcomes after EVAR have not been well defined. Therefore, we examined the effect of COPD severity-not medically treated, medically treated, and with supplementary home oxygen-on the outcomes after EVAR.
Method(s): We identified all patients who had undergone elective infrarenal EVAR within the Vascular Quality Initiative registry from 2011 to 2020. The primary outcome was perioperative mortality. The secondary outcomes were reintubation, delayed extubation (>24 hours after repair), and 5-year mortality. Multivariable logistic regression and Cox regression were used to account for the baseline differences and identify the independent associations of COPD severity on outcomes of interest.
Result(s): A total of 46,335 patients had undergone infrarenal EVAR, of whom 15,532 (33%) had COPD. Of the 15,532 patients with COPD, 28.2% were not medically treated, 56.9% were medically treated, and 14.9% required supplemental home oxygen. Patients with any severity of COPD had increased perioperative mortality (1.5% vs 0.9%; P <.001), reintubation (1.5% vs 0.7%; P <.001), and delayed extubation (0.9% vs 0.5%; P <.001) after EVAR. COPD that was not medically treated and COPD requiring supplemental home oxygen were independently associated with perioperative mortality, reintubation, and delayed extubation (Table). However, COPD that was medically treated was independently associated with reintubation but not with perioperative mortality or delayed extubation. Furthermore, 5-year survival was 86% for patients without COPD, 83% for patients with COPD but not medically treated, 80% for patients with COPD that was medically treated, and 70% for patients with COPD requiring supplemental home oxygen. COPD severity was also independently associated with increased 5-year mortality (Fig).
Conclusion(s): COPD was associated with increased perioperative mortality and respiratory complications after EVAR. Although EVAR might offer improved outcomes compared with open repair, preoperative medical optimization of patients with COPD might improve the perioperative outcomes after EVAR. Furthermore, COPD severity was associated with increased 5-year mortality after repair. Perioperative and long-term outcomes after repair in this patient population should be factored into preoperative clinical decision-making. [Formula presented] [Formula presented]
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Objective: Vascular closure devices (VCDs) and manual compression (MC) are used to achieve hemostasis after peripheral vascular interventions (PVIs). We compared the perioperative outcomes between MC and VCD use after PVI in a multicenter setting.
Method(s): The Vascular Quality Initiative was queried for all lower extremity (LE) PVIs with common femoral artery access performed from 2010 to 2020. The VCDs included were MynxGrip, StarClose SE, Angio-Seal, and Perclose ProGlide. In a blinded fashion, these four VCDs (corresponding to A, B, C, and D) were compared to MC for baseline characteristics, procedure details, and outcomes (access site hematoma and stenosis or occlusion). PVIs with a sheath size >8F were excluded. Propensity score matching (1:1) was performed. Univariable and multivariable analyses were completed for unmatched and matched data, respectively.
Result(s): We identified 84,172 LE PVIs: 32,013 (38%) used MC and 52,159 (62%) used a VCD (A, 12,675; B, 6224; C, 19,872; D, 13,388). Overall, the average age was 68.7 years and 60.4% were men. The indications for PVI were claudication (43.8%), rest pain (13.9%), and tissue loss (40.1%). Compared with MC, VCDs were used more often in patients with obesity, diabetes, and end-stage renal disease (P <.001 for all). VCDs were used less often in patients with hypertension, chronic obstructive pulmonary disease, coronary artery disease, prior percutaneous coronary and extremity interventions, and major amputation (P <.001 for all). VCD use was more common during femoral-popliteal (73% vs 63.8%) and tibial (33.8% vs 22.3%) interventions and less common with iliac interventions (20.6% vs 34.7%; P <.001 for all). Protamine was used less often after VCD usage (19.1% vs 25.6%; P <.001). Overall, 2003 hematomas (2.4%) had developed, of which, 278 (13.9%) had required thrombin or surgical intervention. Compared with MC, any VCD use was associated with fewer hematomas (1.7% vs 3.6%; P <.001) and fewer hematomas requiring intervention (0.2% vs 0.5%; P <.001). When stratified by hemostatic technique, the incidence of any hematoma was as follows: MC, 3.6%; A, 1.4%; B, 1.2%; C, 2.3%; and D, 1.1% (P <.001). The incidence of hematomas requiring intervention was as follows: MC, 0.5%; A, 0.2%; B, 0.2%; C, 0.3%; and D, 0.1% (P <.001). The occurrence of access site stenosis or occlusion was similar between MC and any VCD (0.2% vs 0.2%; P =.12). Multivariable analysis demonstrated that the use of any VCD and individual VCDs vs MC was independently associated with a lower incidence of hematoma (Table). The occurrence of access site stenosis or occlusion was similar between the use of any VCD and MC. Matched analysis revealed similar findings.
Conclusion(s): Although the overall rates of hematomas requiring intervention were low regardless of hemostatic technique, VCD use (irrespective of type) compared favorably to MC, with significantly fewer access site complications after LE PVI. The use of VCDs should be more routine to decrease the incidence of access site complications. [Formula presented]
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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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