Predictors of acute kidney injury after infrarenal abdominal aortic aneurysm repair in octogenarians

Objective

Acute kidney injury (AKI) is a common postoperative complication after abdominal aortic aneurysm (AAA) repair and is associated with significant morbidity and mortality. However, limited studies have investigated this complication in elderly patients. This study aims to evaluate AKI in octogenarians after open endovascular AAA repair (OAR) and endovascular AAA repair (EVAR).

Perioperative and long-term outcomes after open conversion of endovascular aneurysm repair versus primary open aortic repair

BackgroundThe use of endovascular abdominal aortic aneurysm repair (EVAR) has superseded that of open aneurysm repair (OAR) as the procedure of choice for abdominal aortic aneurysm repair. However, significant rates of late reintervention and aneurysm rupture have been reported after EVAR, resulting in the need for conversion to OAR (C-OAR). To assess the relative effects of C-OAR on patients, we compared the outcomes of these patients to those of patients who had undergone P-OAR.MethodsThe data from all patients who had undergone C-OAR and P-OAR in the Vascular Quality Initiative Vascular Implant Surveillance and Interventional Outcomes Network database from 2003 to 2018 were queried. Multivariable logistic regression and Kaplan-Meier survival and Cox proportional hazard regression analyses were used to assess the perioperative long-term outcomes.ResultsA total of 4763 patients were included (91.4%, P-OAR; 8.6%, C-OAR). C-OAR was associated with a significant increase in the odds of perioperative mortality (odds ratio, 1.7; 95% confidence interval [CI], 1.1-2.7; P = .027) and renal complications (odds ratio, 1.5; 95% CI, 1.1-2; P = .004) vs P-OAR. At 5 years, conversion was associated with a higher risk of mortality (hazard ratio [HR], 1.5; 95% CI, 1.3-1.9; P < .001), aneurysmal rupture (HR, 1.9; 95% CI, 1.2-3.1; P = .007), and reintervention (HR, 1.4; 95% CI, 1.05-1.97; P = .022) compared with P-OAR. These results also persisted at 10 years, with conversion associated with a higher risk of mortality (HR, 1.5; 95% CI, 1.2-1.8; P < .001), rupture (HR, 1.8; 95% CI, 1.1-2.8; P = .018), and reintervention (HR, 1.5; 95% CI, 1.1-2.1; P = .010).ConclusionsThe results from the present study have demonstrated that C-OAR is associated with a significantly higher risk of perioperative morbidity and mortality compared with P-OAR. We found a significant increase in mortality, aneurysm rupture, and reintervention at 5 and 10 years of follow-up.     

Systematic review and meta-analysis of sex differences in outcomes after endovascular aneurysm repair for infrarenal abdominal aortic aneurysm

ObjectiveWomen face distinctive challenges when they receive endovascular aneurysm repair (EVAR) treatment, and according to the previous studies, sex differences in outcomes after EVAR for infrarenal abdominal aortic aneurysm (AAA) remains controversial. This study aimed to compare the short-term and long-term outcomes between women and men after EVAR for infrarenal AAA.MethodsWe conducted a comprehensive systematic review and meta-analysis of all available studies reporting sex differences after EVAR for infrarenal AAA, which were retrieved from the MEDICINE, Embase, and Cochrane Database. The pooled results were presented as odds ratios (ORs) for dichotomous data and hazard ratios for time-to-event data using a random effect model.ResultsThirty-six cohorts were included in this meta-analysis. The pooled results showed that women were associated with a significantly increased risk of 30-day mortality (crude OR, 1.67; 95% confidence interval [CI], 1.50-1.87; P < .001; adjusted OR, 1.73; 95% CI, 1.32-2.26; P < .001), in-hospital mortality (OR, 1.90; 95% CI, 1.43-2.53; P < .001), limb ischemia (OR, 2.44; 95% CI, 1.73-2.43; P < .001), renal complications (OR, 1.73; 95% CI, 1.12-2.67; P = .028), cardiac complications (OR, 1.68; 95% CI, 1.01-2.80; P = .046), and long-term all-cause mortality (hazard ratio, 1.23; 95% CI, 1.09-1.38; P = .001) compared with men; however, no significant sex difference was observed for visceral/mesenteric ischemia (OR, 1.62; 95% CI, 0.91-2.88; P = .098), 30-day reinterventions (OR, 1.37; 95% CI, 0.95-1.98; P = .095), late endoleaks (OR, 1.18; 95% CI, 0.88-1.56; P = .264), and late reinterventions (OR, 1.05; 95% CI, 0.78-1.41; P = .741). In the intact AAA subgroup, women had a significantly increased risk of visceral/mesenteric ischemia (OR, 1.85; 95% CI, 1.01-3.39; P = .046) and an equivalent risk of cardiac complications (OR, 1.64; 95% CI, 0.85-3.17; P = .138) compared with men.ConclusionsCompared with male sex, female sex is associated with an increased risk of 30-day mortality, in-hospital mortality, limb ischemia, renal complications, cardiac complications, and long-term all-cause mortality after EVAR for infrarenal AAA. Women should be enrolled in a strict and regular long-term surveillance after EVAR.     

Sex differences in perioperative outcomes after complex abdominal aortic aneurysm repair

ObjectiveFemale sex is associated with worse outcomes after infrarenal abdominal aortic aneurysm (AAA) repair. However, the impact of female sex on complex AAA repair is poorly characterized. Therefore, we compared outcomes between female and male patients after open and endovascular treatment of complex AAA.MethodsWe identified all patients who underwent complex aneurysm repair between 2011 and 2017 in the American College of Surgeons National Surgical Quality Improvement Program targeted vascular module. Complex repairs were defined as those for juxtarenal, pararenal, or suprarenal aneurysms. We compared rates of perioperative adverse events between female and male patients stratified by open AAA repair and endovascular aneurysm repair (EVAR). We calculated propensity scores and used inverse probability-weighted logistic regression to identify independent associations between female sex and our outcomes.ResultsWe identified 2270 complex aneurysm repairs, of which 1260 were EVARs (21.4% female) and 1010 were open repairs (30.7% female). After EVAR, female patients had higher rates of perioperative mortality (6.3% vs 2.4%; P = .001) and major complications (15.9% vs 7.6%; P < .001) compared with male patients. In contrast, after open repair, perioperative mortality was not significantly different (7.4% vs 5.6%; P = .3), and the rate of major complications was similar (29.4% vs 27.4%; P = .53) between female and male patients. Furthermore, even though perioperative mortality was significantly lower after EVAR compared with open repair for male patients (2.4% vs 5.6%; P = .001), this difference was not significant for women (6.3% vs 7.4%; P = .60). On multivariable analysis, female sex remained independently associated with higher perioperative mortality (odds ratio [OR], 2.5; 95% confidence interval [CI], 1.3-4.9; P = .007) and major complications (OR, 2.0; 95% CI, 1.3-3.2; P = .002) in patients treated with EVAR but showed no significant association with mortality (OR, 0.9; 95% CI, 0.5-1.6; P = .69) or major complications (OR, 1.1; 95% CI, 0.8-1.5; P = .74) after open repair. However, the association of female sex with higher perioperative mortality in patients undergoing complex EVAR was attenuated when diameter was replaced with aortic size index in the multivariable analysis (OR, 1.9; 95% CI, 0.9-3.9; P = .091).ConclusionsFemale sex is associated with higher perioperative mortality and more major complications than for male patients after complex EVAR but not after complex open repair. Continuous efforts are warranted to improve the sex discrepancies in patients undergoing endovascular repair of complex AAA.     

Factors associated with in-hospital complications and long-term implications of these complications in elderly patients undergoing endovascular aneurysm repair

ObjectivePerioperative complications in elderly patients undergoing endovascular aneurysm repair (EVAR) occur frequently. Although perioperative mortality has been well-described in the elderly patient population, factors associated with in-hospital complications and their impact on long-term survival remain poorly characterized.MethodsWe identified all patients undergoing elective EVAR for infrarenal AAA within the Vascular Quality Initiative registry (2003-2018) and compared in-hospital complication rates between elderly (age ≥75) and nonelderly patients (<75). We used logistic regression to identify independent factors associated with in-hospital complications, whereas Kaplan-Meier analysis and Cox proportional hazards models were used to determine associations between complications and long-term survival. To assess the effect of complications on early and late survival, we stratified survival periods into the first 30 days after discharge, and between 1 and 6 months, 7 and 12 months, and 1 and 8 years after the index procedure. To investigate the implications of in-hospital morbidity on long-term outcomes, we estimated the adjusted population-attributable fractions of individual complications on both perioperative and long-term survival.ResultsWe identified 17,156 elderly patients and 19,922 nonelderly patients. Elderly patients experienced higher complication rates compared with nonelderly patients (17% vs 10%; P < .001). The factors with the strongest associations with morbidity in elderly patients were anemia (odds ratio [OR], 2.4; 95% confidence interval [CI], 2.2-2.6), female gender (OR, 1.9; 95% CI, 1.7-2.1), and large AAA diameter (OR, 1.7; 95% CI, 1.6-1.9). Patients with any in-hospital complication had lower unadjusted survival estimates than patients without complications at 1 year (83% vs 95%; P < .001), 5 years (66% vs 80%; P < .001), and 8 years (60% vs 72%; P < .001). After risk adjustment, in-hospital complications were independently associated with higher mortality, although the association attenuated over time (first month after discharge: hazard ratio [HR], 5.9; 95% CI, 3.9-9.1; 1-6 months after the procedure: HR, 2.1; 95% CI, 1.7-2.7; P < .001; 7-12 months after the procedure: HR, 1.5; 95% CI, 1.1-1.9; 1-8 years after the procedure: HR, 1.2; 95% CI, 1.01-1.3). Of all deaths occurring within 8 years after procedure, 9.5% were independently associated with in-hospital complications. Complications with the greatest impact on long-term mortality were renal dysfunction (2.4%), blood transfusion (3.4%), and reintubations (2.4%).ConclusionsElderly patients are at higher risk for in-hospital complications after EVAR. These in-hospital complications have a significant impact on both short- and long-term survival. To further improve the delivery of EVAR care nationally, quality improvement efforts should be focused on preventing postoperative morbidity in elderly patients, as well as refining out of hospital surveillance strategies for subjects who experience in-hospital complications to improve overall survival.     

Comparable perioperative mortality outcomes in younger patients undergoing elective open and endovascular abdominal aortic aneurysm repair

BackgroundEvidence for benefit of endovascular aneurysm repair (EVAR) over open surgical repair for de novo infrarenal abdominal aortic aneurysms (AAAs) in younger patients remains conflicting because of heterogeneous study populations and small sample sizes. The objective of this study was to compare perioperative and short-term outcomes for EVAR and open surgery in younger patients using a large national disease and procedure-specific data set.MethodsWe identified patients 65 years of age or younger undergoing first-time elective EVAR or open AAA repair from the Vascular Quality Initiative (2003-2014). We excluded patients with pararenal or thoracoabdominal aneurysms, those medically unfit for open repair, and those undergoing EVAR for isolated iliac aneurysms. Clinical and procedural characteristics were balanced using inverse propensity of treatment weighting. A supplemental analysis extended the study to those younger than 70 years.ResultsWe identified 2641 patients, 73% (n = 1928) EVAR and 27% (n = 713) open repair. The median age was 62 years (interquartile range, 59-64 years), and 13% were female. The median follow-up time was 401 days (interquartile range, 357-459 days). Unadjusted perioperative survival was 99.6% overall (open repair, 99.1%; EVAR, 99.8%; P < .001), with 97.4% 1-year survival overall (open repair, 97.3%; EVAR, 97.4%; P = .9). Unadjusted reintervention rates were five (open repair) and seven (EVAR) reinterventions per 100 person-years (P = .8). After propensity weighting, the absolute incidence of perioperative mortality was <1% in both groups (open repair, 0.9%, EVAR, 0.2%; P < .001), and complication rates were low. Propensity-weighted survival (hazard ratio, 0.88; 95% confidence interval, 0.56-1.38; P = .6) and reintervention rates (open repair, 6; EVAR, 8; reinterventions per 100 person-years; P = .8) did not differ between the two interventions. The analysis of those younger than 70 years showed similar results.ConclusionsIn this study of younger patients undergoing repair of infrarenal AAA, 30-day morbidity and mortality for both open surgery and EVAR are low, and the absolute mortality difference is small. The prior published perioperative mortality and 1-year survival benefit of EVAR over open AAA repair is not observed in younger patients. Further studies of long-term durability are needed to guide decision-making for open repair vs EVAR in this population.     

Long-term outcomes comparing endovascular and open abdominal aortic aneurysm repair in octogenarians

ObjectivePatients older than 80 years have significantly lower early mortality with endovascular aneurysm repair (EVAR) compared with open repair for abdominal aortic aneurysms (AAAs), but long-term results remain poorly studied. We analyzed the results of both emergent and elective AAA repair in patients aged 80 years or older who had at least 5 years of follow-up.MethodsRetrospective review of a prospectively collected vascular surgery database was performed to identify all patients who underwent elective repair of an AAA between 2007 and 2012 and were 80 years of age or older at the time of surgery. Open and EVAR groups were compared using univariate statistics.ResultsThe study cohort was composed of 314 patients 80 years of age or older (median, 83 years; interquartile range, 5 years) who underwent repair (96 open, 218 EVAR). The groups had similar comorbidities, except that EVAR patients were more likely to be male and open repair patients were more likely to have larger aneurysms. Compared with open repair, elective early postoperative mortality was significantly lower for EVAR patients (1% vs 14%; P < .001). Overall mean life expectancy was 5.9 years (EVAR, 5.8 years; open repair, 5.8 years; P = .98). The 1-year survival was significantly higher for EVAR (92.9%) than for open repair (84.1%; P = .02). The 2-year survival (EVAR, 83.4%; open repair, 74.6%; P = .07) and 5-year survival (EVAR, 57.8%; open repair, 60.3%; P = .98) did not differ between EVAR and open repair. Reintervention rates (EVAR, 18%; open repair, 2%; P = .05) were higher in the endovascular treatment group.ConclusionsEVAR results in an improved 1-year mortality in octogenarians compared with open repair, although 5-year survival is similar between the groups. With average life expectancies of >5 years and an 18% reintervention rate, diligent follow-up is required after EVAR even in elderly patients.     

Fenestrated endovascular aneurysm repair is associated with lower perioperative morbidity and mortality compared with open repair for complex abdominal aortic aneurysms

ObjectiveThe Zenith Fenestrated Endovascular Graft (ZFEN; Cook Medical, Bloomington, Ind) has expanded the anatomic eligibility of endovascular aneurysm repair (EVAR) for complex abdominal aortic aneurysms (AAAs). Current data on ZFEN mainly consist of single-institution experiences and show conflicting results. Therefore, we compared perioperative outcomes after repair using ZFEN with open complex AAA repair and infrarenal EVAR in a nationwide multicenter registry.MethodsWe identified all patients undergoing elective AAA repair using ZFEN, open complex AAA repair, and standard infrarenal EVAR between 2012 and 2016 within the American College of Surgeons National Surgical Quality Improvement Program targeted vascular module. Open complex AAA repairs were defined as those with a juxtarenal or suprarenal proximal AAA extent in combination with an aortic cross-clamping position that was above at least one renal artery. The primary outcome was perioperative mortality, defined as death within 30 days or within the index hospitalization. Secondary outcomes included postoperative renal dysfunction (creatinine concentration increase of >2 mg/dL from preoperative value or new dialysis), occurrence of any complication, procedure times, blood transfusion rates, and length of stay. To account for baseline differences, we calculated propensity scores and employed inverse probability-weighted logistic regression.ResultsWe identified 6825 AAA repairs—220 ZFENs, 181 open complex AAA repairs, and 6424 infrarenal EVARs. Univariate analysis of ZFEN compared with open complex AAA repair demonstrated lower rates of perioperative mortality (1.8% vs 8.8%; P = .001), postoperative renal dysfunction (1.4% vs 7.7%; P = .002), and overall complications (11% vs 33%; P < .001). In addition, fewer patients undergoing ZFEN received blood transfusions (22% vs 73%; P < .001), and median length of stay was shorter (2 vs 7 days; P < .001). After adjustment, open complex AAA repair was associated with higher odds of perioperative mortality (odds ratio [OR], 4.9; 95% confidence interval [CI], 1.4-18), postoperative renal dysfunction (OR, 13; 95% CI, 3.6-49), and overall complication rates (OR, 4.2; 95% CI, 2.3-7.5) compared with ZFEN. Compared with infrarenal EVAR, ZFEN presented comparable rates of perioperative mortality (1.8% vs 0.8%; P = .084), renal dysfunction (1.4% vs 0.7%; P = .19), and any complication (11% vs 7.7%; P = .09). Furthermore, after adjustment, there was no significant difference between the odds of perioperative mortality, postoperative renal dysfunction, or any complication between infrarenal EVAR and ZFEN.ConclusionsZFEN is associated with lower perioperative morbidity and mortality compared with open complex AAA repair, and outcomes are comparable to those of infrarenal EVAR. Long-term durability of ZFEN compared with open complex AAA repair warrants future research.     

Comparison of midterm results of endovascular aneurysm repair for ruptured and elective abdominal aortic aneurysms

ObjectiveEndovascular aneurysm repair (EVAR) became an increasingly preferred modality for abdominal aortic aneurysm (AAA) repair both in elective AAA repair (el-EVAR) and EVAR of a ruptured AAA (r-EVAR) setting. Ruptured AAAs usually have more hostile anatomies and less time for planning. Consequently, more complications may arise after r-EVAR. The purpose of this study was to compare mi-term outcomes between r-EVAR and el-EVAR.MethodsA retrospective cohort analysis of patients undergoing EVAR from 2000 to 2015 at a tertiary institution was performed. Patients with previous aortic surgery, nonatherosclerotic AAA and isolated iliac aneurysms were excluded. In-hospital casualties or patients who were intraoperatively converted to open repair were also excluded. For the midterm outcome analysis, only patients with at least two postoperative examinations (a 30-day computed tomography scan and a second postoperative examination performed 6 months or later) were considered. The primary end point was freedom from aneurysm-related complications (a composite of type I or III endoleak, aneurysm sac growth, migration of more than 5 mm, device integrity failure, AAA-related death, late postimplant rupture, or AAA-related secondary intervention). Freedom from secondary interventions, neck-related events (defined as a composite of type IA endoleak, migration of more than 5 mm, or preemptive neck-related secondary intervention) and late survival were secondary end points. The impact of device instructions for use (IFU) compliance on neck events was also assessed.ResultsThe study included 565 patients (65 r-EVAR and 500 el-EVAR). Eighty-two patients were treated outside proximal neck IFU, 13 in the r-EVAR group (21.3%) and 69 (14.5%) in the el-EVAR (P = .16). During the index hospitalization, there were more complications (12.3% vs 3.2%; P = .001) and reinterventions (12.3% vs 2.8%; P < .001) in the r-EVAR group. After discharge, median clinical follow-up time was 4.3 years (interquartile range, 2.1-7.0 years) without differences between both groups. Five-year freedom from AAA-related complications was 53.9% in the r-EVAR group and 65.4% in the el-EVAR (P = .21). In multivariable analysis the r-EVAR group was not at increased risk for late complications (hazard ratio [HR], 0.94; 95% confidence interval [CI], 0.54-1.61; P = .81). Five-year freedom from neck-related events was 74% in r-EVAR and 82% in the el-EVAR group (P = .345). Patients treated outside neck IFU were at greater risk for neck-related events both in r-EVAR (HR, 6.5; 95% CI, 1.8-22.9; P = .004) and el-EVAR group (HR, 2.6; 95% CI, 1.5-4.5; P < .001). Freedom from secondary interventions at 5 years was 63.0% for r-EVAR and 76.9% for el-EVAR (P = .16). Survival at 5 years was 68.8% in the r-EVAR group and 73.3% in the el-EVAR group (P = .30).ConclusionsDurable and sustainable midterm outcomes were found for both r-EVAR and el-EVAR patients who survived the postoperative period. Patients treated outside the IFU are at greater risk for late complications. Surveillance protocols may be tailored according to individual anatomy and IFU compliance rather than timing of repair.     

Mortality analysis of endovascular aneurysm sealing versus endovascular aneurysm repair

BackgroundEndovascular aneurysm sealing (EVAS), using the Nellix endovascular aneurysm sealing system, has been associated with high reintervention and migration rates. However, prior reports have suggested that EVAS might be related to a lower all-cause mortality compared with endovascular aneurysm repair (EVAR). In the present study, we examined the 5-year all-cause mortality trends after EVAS and EVAR.MethodsWe compared the 333 EVAS patients in the EVAS-1 Nellix U.S. investigational device exemption trial with 16,497 infrarenal EVAR controls from the Vascular Quality Initiative, treated between 2014 and 2016, after applying the exclusion criteria from the investigational device exemption trial (ie, hemodialysis, creatinine >2.0 mg/dL, rupture). As a secondary analysis, we stratified the patients by aneurysm diameter (<5.5 cm and ≥5.5 cm). We calculated propensity scores after adjusting for demographics, comorbidities, and anatomic characteristics and applied inverse probability weighting to compare the risk-adjusted long-term mortality using Kaplan-Meier and Cox regression analyses.ResultsAfter weighting, the EVAS group had experienced similar 5-year mortality compared with the controls from the Vascular Quality Initiative (EVAS vs EVAR, 18% vs 14%; hazard ratio [HR], 1.1; 95% confidence interval [CI], 0.71-1.7; P = .70). The subgroup analysis demonstrated that for patients with an aneurysm diameter of <5.5 cm, EVAS was associated with higher 5-year mortality compared with EVAR (19% vs 11%; HR, 2.4; 95% CI, 1.7-4.7; P = .013). In patients with an aneurysm diameter of ≥5.5 cm, EVAS was associated with lower mortality within the first 2 years (2-year mortality: HR, 0.29; 95% CI, 0.13-0.62; P = .002). However, compared with EVAR, EVAS was associated with higher mortality between 2 and 5 years (HR, 1.9; 95% CI, 1.2-3.0; P = .005), with no mortality difference at 5 years (18% vs 17%; HR, 0.82; 95% CI, 0.4-1.4; P = .46).ConclusionsWithin the overall population, EVAS was associated with similar 5-year mortality compared with EVAR. EVAS was associated with higher mortality for those with small aneurysms (<5.5 cm). For those with larger aneurysms (≥5.5 cm), EVAS was initially associated with lower mortality within the first 2 years, although this advantage was lost thereafter, with higher mortality after 2 years. Future studies are required to evaluate the specific causes of death and to elucidate the potential beneficial mechanism behind sac obliteration that leads to this potential initial survival benefit. This could help guide the development of future grafts with better proximal fixation and sealing that also incorporate sac obliteration.     

Factors associated with symptomatic postoperative myocardial infarction after endovascular aneurysm repair

ObjectiveEndovascular aneurysm repair (EVAR) has now become the most common operation to treat abdominal aortic aneurysms (AAAs). One of the perceived benefits of EVAR over open AAA repair is reduced incidence of perioperative cardiac complications and mortality. The purpose of this study was to determine risk factors associated with postoperative myocardial infarction (POMI) in patients who have undergone EVAR.MethodsData were obtained from the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) database for the years 2012 to 2015 in the Participant Use Data File. All patients in the database who underwent EVAR during this time were identified. These patients were then divided into two groups: those with POMI and those without. Bivariate analysis was done for preoperative, intraoperative, and postoperative risk factors, followed by multivariable analysis to determine associations of independent variables with POMI. A risk prediction model for POMI was created to accurately predict incidence of POMI after EVAR.ResultsA total of 7702 patients (81.3% male, 18.7% female) were identified who underwent EVAR from 2011 to 2015. Of these patients, 110 (1.4%) had POMI and 7592 (98.6%) did not. Several risk factors were related to an increased risk of POMI, including dependent functional health status, need for lower extremity revascularization, longer operation time, and ruptured AAA (P < .05, all).On multivariable analysis, the following factors were found to have significant associations with POMI: return to operating room (odds ratio [OR], 1.84; confidence interval [CI], 1.10-3.09; P = .020), ruptured AAA (OR, 1.87; CI, 1.18-2.95; P = .008), pneumonia (OR, 1.94; CI, 1.01-3.73; P = .048), age >80 years (compared with <70 years; OR, 2.30; CI, 1.36-3.86; P = .002), unplanned intubation (OR, 4.07; CI, 2.31-7.18; P < .001), and length of hospital stay >6 days (OR, 8.43; CI, 4.75-14.94; P < .001). The risk prediction model showed that in the presence of all these risk factors, the incidence of POMI was 58.3%. The incidence of cardiac arrest and death was significantly higher for patients with POMI compared with patients without POMI (cardiac arrest, 11.9% vs 1.3%; death, 10.2% vs 1.1%).ConclusionsIn patients who undergo EVAR, the risk of POMI is increased for those who are older, who present with a ruptured AAA, who have pneumonia, who have unplanned intubation, and who have prolonged hospital stay. Patients who suffer from POMI have higher risk of having cardiac arrest and death.     

Real-world cost analysis of endovascular repair versus open repair in patients with nonruptured abdominal aortic aneurysms

BackgroundThe aim of this study was to provide a nationwide, all-payer, real-world cost analysis of endovascular aortic aneurysm repair (EVAR) versus open aortic aneurysm repair (OAR) in patients with nonruptured abdominal aortic aneurysms (non-rAAA).MethodsAll non-rAAA patients registered between July 2009 and March 2015 in the Premier Healthcare Database were analyzed. The Student t-test and the χ² test were used for continuous and categorical variables, respectively; median value comparisons were done with the Wilcoxon-Mann-Whitney rank-sum test. The in-hospital absolute mean total cost (sum of fixed cost and variable cost) and subcategories were analyzed after adjustment for inflation at July 2015. Fixed costs included all overhead costs while variables costs included in-hospital services including procedures, room and board, services provided by hospital staff, and pharmacy costs. Total cost was stratified based on admission type (emergency vs nonemergency), 75th percentile of length of hospital stay among individual procedures (expected vs extended stay), mortality, and complications. Student t-test and Fisher's analysis of variance were used for comparing mean cost. Year-wise comparison of mean cost was done with analysis of variance to look for a trend over time.ResultsOur study cohort included 38,809 non-rAAA patients (33,171 EVAR and 5638 OAR). The mean total cost of index admission was lower in EVAR in comparison with OAR ($32,052 vs $36,091; P < .001), with lower fixed costs ($11,309 vs $16,818; P < .001) and higher variable costs ($20,743 vs $19,272; P < .001). Cost of pharmacy, labor, operating room, room and board and other costs were significantly higher with OAR, whereas the supply cost was higher with EVAR. The expected hospital length of stay of patients who underwent EVAR was associated with a higher total cost ($27,271 vs $25,680; P < .001) and a higher variable cost ($18,186 vs $13,671; P < .001) than OAR patients. However, the extended hospital stay of patients who underwent EVAR had lower costs in all categories compared with the extended length of stay of those who underwent OAR. Mortality associated with EVAR was costlier than OAR associated mortality (mean $72,483 vs $59,804; P = .017). From 2009 to 2014, the mean total cost of EVAR increased significantly by 18.5% ($28,745 vs $34,049; P < .001) owing to a 7.8% increase in fixed costs ($10,931 vs $11,789; P < .001) and a 25.0% increase in variable costs ($17,804 vs $22,257; P < .001). The mean total cost OAR remained stable over time.ConclusionsOverall hospitalization costs associated with EVAR of non-rAAA was lower than the hospitalization cost of OAR. Interestingly, we found that, among patients who had an expected hospital length of stay, the hospitalization cost after OAR was significantly lower than after EVAR. The average hospitalization cost of OAR was stable during the 5 years study period, whereas the hospitalization cost of EVAR increased significantly over time. Further studies are required to identify reasons for increased costs associated with EVAR.     

Loss of follow-up after carotid revascularization is associated with worse long-term stroke and death

ObjectivesSociety for Vascular Surgery practice guidelines recommend surveillance with duplex ultrasound scanning at baseline (within 3 months from discharge), every 6 months for 2 years, and annually afterward following carotid endarterectomy or carotid artery stenting. There is a growing concern regarding the significance of postoperative follow-up after several vascular procedures. We sought to determine whether 1-year loss to follow-up (LTF) after carotid revascularization was associated with worse outcomes in the Vascular Quality Initiative (VQI) linked to Vascular Implant Surveillance and Interventional Outcomes Network (VISION) database.MethodsAll patients who underwent carotid revascularization in the VQI VISION database between 2003 and 2016 were included. LTF was defined as failure to complete 1-year follow-up in the VQI long-term follow-up dataset. Data about stroke and mortality were captured in the VISION dataset using a list of Current Procedural Terminology, International Classification of Diseases (Ninth Revision), and International Classification of Diseases (Tenth Revision) codes linked to index procedures in VQI. Kaplan-Meier life-table methods and Cox proportional hazard modeling were used to compare 5- and 10-year outcomes between patients with no LTF and those who were LTF.ResultsA total of 58,840 patients were available for analysis. The 1-year LTF rate was 43.8%. Patients who were LTF were older and more frequently symptomatic, with chronic obstructive pulmonary diseases, chronic kidney diseases, and congestive heart failure. Also, patients who underwent carotid artery stenting were more likely to be LTF compared with carotid endarterectomy patients (54.5% vs 42.3%; P < .001). The incidence of postoperative (30 days) stroke was higher in the LTF group (2.9% vs 1.7%; P < .001). Cox regression analysis revealed that LTF was associated with an increased risk of long-term stroke at 5 years (hazard ratio [HR]: 1.4, 95% confidence interval [CI]: 1.2-1.6; P < .001) and 10 years (HR: 1.3, 95% CI: 1.2-1.5; P < .001). It was also associated with significantly higher mortality at 5 years (HR: 2.5, 95% CI: 2.3-2.8; P < .001) and 10 years (HR: 2.2, 95% CI: 1.9-2.5; P < .001). Stroke or death was significantly worse in the LTF group at 5 years (HR: 2.3, 95% CI: 2.1-2.5; P < .001) and up to 10 years (HR: 2.02, 95% CI: 1.8-2.3; P < .001).ConclusionsOne-year follow-up after carotid revascularization procedures was found to be associated with better stroke- and mortality-free survival. Surgeons should emphasize the importance of follow-up to all patients who undergo carotid revascularization, especially those with multiple comorbidities and postoperative neurological complications.     

Infrarenal endovascular aneurysm repair with large device (34- to 36-mm) diameters is associated with higher risk of proximal fixation failure

ObjectiveEndovascular aneurysm repair (EVAR) has become the standard of care for infrarenal aneurysms. Endografts are commercially available in proximal diameters up to 36 mm, allowing proximal seal in necks up to 32 mm. We sought to further investigate clinical outcomes after standard EVAR in patients requiring large main body devices.MethodsWe performed a retrospective review of a prospectively maintained database for all patients undergoing elective EVAR for infrarenal abdominal aortic aneurysms at a single institution from 2000 to 2016. Only endografts with the option of a 34- to 36-mm proximal diameter were included. Requisite patient demographics, anatomic and device-related variables, and relevant clinical outcomes and imaging were reviewed. The primary outcome in this study was proximal fixation failure, which was a composite of type IA endoleak and stent graft migration >10 mm after EVAR. Outcomes were stratified by device diameter for the large-diameter device cohort (34-36 mm) and the normal-diameter device cohort (<34 mm).ResultsThere were 500 patients treated with EVAR who met the inclusion criteria. A total of 108 (21.6%) patients received large-diameter devices. There was no difference between the large-diameter cohort and the normal-diameter cohort in terms of 30-day (0.9% vs 0.95%; P = .960) or 1-year mortality (9.0% vs 6.2%; P = .920). Proximal fixation failure occurred in 24 of 392 (6.1%) patients in the normal-diameter cohort and 26 of 108 (24%) patients in the large-diameter cohort (P < .001). There were 13 (3.3%) type IA endoleaks in the normal-diameter cohort and 16 (14.8%) in the large-diameter cohort (P < .001). Stent graft migration (>10 mm) occurred in 15 (3.8%) in the normal-diameter cohort and 16 (14.8%) in the large-diameter cohort (P < .001). After multivariate analysis, only the use of Talent (Medtronic, Minneapolis, Minn) endografts (odds ratio [OR], 4.50; 95% confidence interval [CI], 1.18-17.21) and neck diameter ≥29 mm (OR, 2.50; 95% CI, 1.12-5.08) remained significant independent risk factors for development of proximal fixation failure (OR, 3.99; 95% CI, 1.75-9.11).ConclusionsStandard EVAR in patients with large infrarenal necks ≥29 mm requiring a 34- to 36-mm-diameter endograft is independently associated with an increased rate of proximal fixation failure. This group of patients should be considered for more proximal seal strategies with fenestrated or branched devices vs open repair. Also, this group likely needs more stringent radiographic follow-up.     

A population-based cohort study examining the risk of abdominal cancer after endovascular abdominal aortic aneurysm repair

ObjectiveEndovascular aneurysm repair (EVAR) has increasingly been used as the primary treatment approach for abdominal aortic aneurysm (AAA). This study examined the hypothesis that EVAR leads to an increased risk of abdominal cancer within the radiation field compared with open AAA repair.MethodsThe nationwide English Hospital Episode Statistics database was used to identify all patients older than 50 years who received an AAA repair in 2005 to 2013. EVAR and open AAA repair groups were compared for the incidence of postoperative cancer using inverse probability weights and G-computation formula to adjust for selection bias and confounding.ResultsAmong 14,150 patients who underwent EVAR and 24,645 patients who underwent open AAA repair, follow-up was up to 7 years. EVAR was associated with an increased risk of postoperative abdominal cancer (hazard ratio [HR], 1.14; 95% confidence interval [CI], 1.03-1.27) and all cancers (HR, 1.09; 95% CI, 1.02-1.17). However, there was no difference between the groups in the risk of lung cancer (HR, 1.04; 95% CI, 0.92-1.18) or obesity-related nonabdominal cancer (HR, 1.12; 95% CI, 0.69-1.83). Within the EVAR group, use of computed tomography surveillance was not associated with any increased risk of abdominal cancer (HR, 0.94; 95% CI, 0.71-1.23) or all cancers (HR, 0.97; 95% CI, 0.81-1.17).ConclusionsThis study suggests an increased risk of abdominal cancer after EVAR compared with open AAA repair. The differential cancer risk should be further explored in alternative national populations, and radiation exposure during EVAR should be measured as a quality metric in the assessment of EVAR centers.     

Prognosis review and time-to-event data meta-analysis of endovascular aneurysm repair outside versus within instructions for use of aortic endograft devices

BackgroundOur objective was to investigate whether patients undergoing standard endovascular aneurysm repair (EVAR) outside the instructions for use (IFU) have worse outcomes than patients treated within IFU.MethodsWe conducted a systematic review according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Electronic bibliographic sources were searched up to January 2019 using a combination of controlled vocabulary (thesaurus) and free-text terms to identify studies comparing outcomes of EVAR in patients treated outside versus within IFU. Pooled estimates of dichotomous outcomes were calculated using odds ratio (OR) or risk difference (RD) and 95% confidence interval (CI). We conducted a time-to-event data meta-analysis using the inverse-variance method and reported the results as summary hazard ratio (HR) and associated 95% CI. Random-effects methods of meta-analysis were applied. We formed meta-regression models to explore heterogeneity as a result of changes in practice over time.ResultsWe identified 17 observational cohort studies published between 2011 and 2017, reporting a total of 4498 patients. The pooled prevalence of EVAR performed outside the IFU was 40% (95% CI, 33-48). Nonadherence to IFU was not associated with increased risk of perioperative mortality (RD, 0.01; 95% CI, −0.00 to 0.01; P = .23), aneurysm rupture (HR, 1.34; 95% CI, 0.30-5.93; P = .70), aneurysm-related mortality (HR, 0.88; 95% CI, 0.20-3.84; P = .86), technical failure (RD, 0.01; 95% CI, −0.03 to 0.05; P = .56), requirement for adjunctive procedures (OR, 1.48; 95% CI, 0.81-2.71; P = .20), type I endoleak (HR, 2.28; 95% CI, 0.58-8.91; P = .24), aneurysm sac expansion (HR, 0.86; 95% CI, 0.55-1.33; P = .49), or aneurysm-related reintervention (HR, 1.04; 95% CI, 0.81-1.34; P = .74). The overall mortality was significantly higher in patients treated outside the IFU (HR, 1.20; 95% CI, 1.02-1.42; P = .03). Meta-regression showed that the prevalence of EVAR performed outside the IFU has increased over time (P = .019).ConclusionsStandard EVAR outside the IFU was not found to have worse aneurysm-related outcomes than treatment within the IFU. Standard EVAR outside the IFU could be considered in selected patients who are deemed high risk for complex open or endovascular surgery.     

Proximal aortic repair in dialysis patients: A national database analysis

ObjectivesDialysis is a well-established risk factor for morbidity and mortality after cardiovascular procedures. However, little is known regarding the outcomes of proximal aortic surgery in this high-risk cohort.MethodsPerioperative (in-hospital or 30-day mortality) and 10-year outcomes were analyzed for all the patients who underwent open proximal aortic repair with the diagnosis of nonruptured thoracic aortic aneurysm (aneurysm, n = 325) or type A aortic dissection (dissection, n = 461) from 1987 to 2015 using the US Renal Data System database.ResultsIn patients with aneurysm, perioperative mortality was 12.6%. The 10-year mortality was 81% ± 3%. Age 65 years or more (hazard ratio [HR], 1.35; 95% confidence interval [CI], 1.03 to 1.78; P = .03), chronic obstructive pulmonary disease (HR, 1.68; 95% CI, 1.01-2.82; P = .047), and Black race (HR, 1.46; 95% CI, 1.09-1.97; P = .01) were independently associated with worse 10-year mortality. In patients with dissection, perioperative mortality was 24.3% and 10-year mortality was 87.9% ± 2.2%. Age 65 years or more (HR, 1.49; 95% CI, 1.19-1.86; P < .001), congestive heart failure (HR, 1.39; 95% CI, 1.11-2.57; P = .004), and diabetes mellitus as the cause of dialysis (HR, 1.75; 95% CI, 1.2-2.57; P = .004) were independently associated with worse 10-year mortality. Black race (HR, 0.74; 95% CI, 0.6-0.92; P = .008) was associated with a better outcome.ConclusionsWe described challenging perioperative and 10-year outcomes for dialysis patients undergoing proximal aortic repair. The present study suggests the need for careful patient selection in the elective repair of proximal aortic aneurysm for dialysis-dependent patients, whereas it affirms the feasibility of emergency surgery for acute type A aortic dissections.     

Anatomic predictors for late mortality after standard endovascular aneurysm repair

ObjectiveAbdominal aortic aneurysm (AAA) management involves a decision process that takes into account anatomic characteristics, surgical risks, patients' preferences, and expected survival. Whereas larger AAA diameter has been associated with increased mortality after both standard endovascular aneurysm repair (EVAR) and open repair, it is unclear whether survival after EVAR is influenced by other anatomic characteristics. The purpose of this study was to determine the importance of baseline anatomic features on survival after EVAR.MethodsAll patients treated at a tertiary teaching center with EVAR for intact standard infrarenal AAA from 2000 to 2014 were included. The civil data registry was queried to determine survival status; causes of death were obtained from death certificates. The primary study end point was to determine the impact of baseline morphologic features on all-cause and cardiovascular mortality after EVAR.ResultsThis study included 404 EVAR patients (12.1% women; mean age, 73 years) with a median follow-up of 5.8 years (interquartile range, 3.1-7.4 years). The 5- and 10-year overall survival rates for the entire population after EVAR were 70% (95% confidence interval [CI], 66%-75%) and 43% (95% CI, 37%-50%), respectively. Only AAA diameter >70 mm (hazard ratio [HR], 1.75; 95% CI, 1.20-3.56) was identified as an independent anatomic predictor of all-cause mortality. Death due to cardiovascular causes occurred in 60 (38.5%) patients. Aneurysm-related mortality was responsible for six of the cardiovascular-related deaths. In multivariable analysis, both neck diameter ≥30 mm (HR, 2.16; 95% CI, 1.05-4.43) and AAA diameter >70 mm (HR, 2.45; 95% CI, 1.34-4.46) were identified as independent morphologic risk factors for cardiovascular mortality, whereas >25% circumferential neck thrombus (HR, 0.32; 95% CI, 0.13-0.77) was protective.ConclusionsThis study suggests that patients with AAA diameters >70 mm are at increased risk of all-cause and cardiovascular mortality. In addition, patients with infrarenal neck diameters ≥30 mm have a greater risk of cardiovascular mortality, although AAA-related deaths were not more frequent in this group of patients. Consequently, a more aggressive management of cardiovascular medical comorbidities may be warranted to improve survival after standard EVAR in these patients.     

Predictors of midterm high-grade restenosis after carotid revascularization in a multicenter national database

BackgroundRestenosis after carotid revascularization is clinically challenging. Several studies have looked into the management of recurrent restenosis; however, studies looking into factors associated with restenosis are limited. This study evaluated the predictors of restenosis after carotid artery stenting (CAS) and carotid endarterectomy (CEA) using a large national database.MethodsPatients undergoing CEA or CAS in the Vascular Quality Initiative data set (2003-2016) were analyzed. Patients with no follow-up (33%) and those who had prior ipsilateral CEA or CAS were excluded. Significant restenosis was defined as ≥70% diameter-reducing stenosis, target artery occlusion or peak systolic velocity ≥300 cm/s, or repeated revascularization. Kaplan-Meier survival analysis and bootstrapped Cox regression models with stepwise forward and backward selection were used.ResultsA total of 35,720 procedures were included (CEA, 31,329; CAS, 4391). No significant difference in restenosis rates was seen between CEA and CAS at 2 years (7.7% vs 9.4% [P = .09]; hazard ratio [HR], 0.99; 95% confidence interval [CI], 0.79-1.25; P = .97). However, after adjustment for age, sex, and symptomatic status at the time of the index operation, CAS patients who had postoperative restenosis were more likely to have a symptomatic presentation (odds ratio, 2.2; 95% CI, 1.2-4.0; P = .01) and to undergo repeated revascularization at 2 years (HR, 1.75; 95% CI, 1.3-2.4; P < .001) compared with patients who had restenosis after CEA. Predictors of restenosis after CAS included a common carotid artery lesion (HR, 1.65; 95% CI,1.06-2.57; P = .03), whereas age (HR, 0.91; 95% CI, 0.84-0.99; P = .03) and dilation after stent placement (HR, 0.53; 95% CI, 0.39-0.72; P < .001) were associated with decreased restenosis at 2 years. Predictors of restenosis after CEA included female sex (HR, 1.55; 95% CI, 1.38-1.74; P < .001), prior neck irradiation (HR, 2.35; 95% CI, 1.66-3.30; P < .001), and prior bypass surgery (HR, 1.29; 95% CI, 1.01-1.65; P = .04). On the other hand, factors associated with decreased restenosis after CEA included age (HR, 0.95; 95% CI, 0.92-0.98; P < .001), black race (HR, 0.57; 95% CI, 0.37-0.89; P = .01), patching (HR, 0.61; 95% CI, 0.47-0.79; P < .001), and completion imaging (HR, 0.70; 95% CI, 0.52-0.95; P = .02).ConclusionsOur results show no significant difference in restenosis rates at 2 years between CEA and CAS. Restenosis after CAS is more likely to be manifested with symptoms and to undergo repeated revascularization compared with that after CEA. Poststent ballooning after CAS and completion imaging and patching after CEA are associated with decreased hazard of restenosis; however, further research is needed to assess longer term outcomes and to balance the risks vs benefits of certain practices, such as poststent ballooning.     

Anemia and postoperative outcomes after open and endovascular repair of intact abdominal aortic aneurysms

Objective

Anemia is associated with increased cardiac adverse events during the early postoperative period because of high physiologic stress and increased cardiac demand. The aim of this study was to assess the surgical outcomes and prognostic implications of anemia in patients undergoing repair of intact abdominal aortic aneurysms (AAAs).