Comparison of Endovascular Stent Grafts for Abdominal Aortic Aneurysm Repair in Medicare Beneficiaries.

BACKGROUND: Increased renal complications have been suggested with suprarenal stent grafts, but long-term analyses have been limited. Therefore, the purpose of this study was to evaluate the effect of endograft choice on perioperative and long-term outcomes. METHODS: We compared Medicare beneficiaries undergoing endovascular abdominal aortic aneurysms repair from 2005 to 2008 with endografts with infrarenal fixation and a single docking limb (AneuRx, Excluder) to those with suprarenal fixation and 2 docking limbs (Zenith), or a unibody configuration (Powerlink). Propensity score weighting accounted for differences in patient characteristics among the different graft formations, and perioperative mortality, complications, and length of stay and 4-year rates of survival, rupture, and reintervention were compared. RESULTS: Forty-six thousand one hundred seventy-one Medicare beneficiaries were identified including 11,002 (24%) with suprarenal fixation, 32,909 (71%) with infrarenal fixation, and 2,260 (5%) with a unibody graft. After propensity score weighting, there were no significant differences in patients' baseline clinical and demographic characteristics. The suprarenal fixation patients had higher rates of perioperative mortality (1.7% vs. 1.3%, P < 0.01), renal failure (6.0% vs. 4.7%, P < 0.001), and mesenteric ischemia (0.7% vs. 0.4%, P < 0.01) and longer length of stay (3.4 days vs. 3.0 days, P < 0.001) compared with patients with infrarenal fixation. Unibody grafts had higher rates of renal failure (5.9% vs. 4.7%, P < 0.001), mesenteric ischemia (1.0% vs. 0.4%, P < 0.001), and conversion to open repair (0.7% vs. 0.1%, P < 0.001) compared to those with infrarenal fixation and single docking limbs. At 4 years, mortality remained slightly higher with suprarenal compared to infrarenal fixation (30% vs. 29%, P = 0.047), although these patients had fewer conversions to open repair (0.6% vs. 0.9%, P = 0.03) and aneurysm-related reinterventions (10% vs. 12%, P < 0.01). At 4 years, unibody grafts had more aneurysm-related interventions compared to infrarenal fixation grafts (15% vs. 12%, P < 0.01) but fewer conversions to open repair (0.4% vs. 0.9%, P = 0.02). Late rupture did not differ among the groups. CONCLUSIONS: Compared to infrarenal fixation devices, patients who underwent EVAR with suprarenal fixation had higher perioperative mortality and renal complications but fewer reinterventions including conversion, while the unibody graft had more perioperative complications and aneurysm-related reinterventions, but fewer conversions to open repair. Although these differences could be explained by selection bias, these data suggest that further comparative effectiveness analyses should be performed to understand the outcomes following EVAR with suprarenal fixation and unibody grafts.

The impact of endovascular repair on management and outcome of ruptured thoracic aortic aneurysms.

BACKGROUND: Thoracic endovascular aortic repair (TEVAR) has become an alternative to open repair for the treatment of ruptured thoracic aortic aneurysms (rTAAs). The aim of this study was to assess national trends in the use of TEVAR for the treatment of rTAA and to determine its impact on perioperative outcomes. METHODS: Patients admitted with an rTAA between 1993 and 2012 were identified from the National Inpatient Sample. Patients were grouped in accordance with their treatment: TEVAR, open repair, or nonoperative treatment. The primary outcomes were treatment trends over time and in-hospital death. Secondary outcomes included perioperative complications and length of stay. Trend analyses were performed using the Cochran-Armitage test for trend, and adjusted mortality risks were established using multivariable logistic regression analysis. RESULTS: A total of 12,399 patients were included, with 1622 (13%) undergoing TEVAR, 2808 (23%) undergoing open repair, and 7969 (64%) not undergoing surgical treatment. TEVAR has been increasingly used from 2% of total admissions in 2003-2004 to 43% in 2011-2012 (P < .001). Concurrently, there was a decline in the proportion of patients undergoing open repair (29% to 12%; P < .001) and nonoperative treatment (69% to 45%; P < .001). The proportion of patients undergoing surgical repair has increased for all age groups since 1993-1994 (P < .001 for all) but was most pronounced among those aged 80 years with a 7.5-fold increase. After TEVAR was introduced, procedural mortality decreased from 36% in 2003-2004 to 27% in 2011-2012 (P < .001); mortality among those undergoing nonoperative treatment remained stable between 63% and 60% (P = .167). Overall mortality after rTAA admission decreased from 55% to 42% (P < .001). Since 2005, mortality for open repair was 33% and 22% for TEVAR (P < .001). In adjusted analysis, open repair was associated with a twofold higher mortality than TEVAR (odds ratio, 2.0; 95% confidence interval, 1.7-2.5). CONCLUSIONS: TEVAR has replaced open repair as primary surgical treatment for rTAA. The introduction of endovascular treatment appears to have broadened the eligibility of patients for surgical treatment, particularly among the elderly. Mortality after rTAA admission has declined since the introduction of TEVAR, which is the result of improved operative mortality as well as the increased proportion of patients undergoing surgical repair.

Significant regional variation exists in morbidity and mortality after repair of abdominal aortic aneurysm.

OBJECTIVE: Limited data exist comparing perioperative morbidity and mortality after open and endovascular abdominal aortic aneurysm (AAA) repair (EVAR) among regions of the United States. This study evaluated the regional variation in mortality and perioperative outcomes after repair of AAAs. METHODS: The Vascular Quality Initiative (VQI) was used to identify patients undergoing open AAA repair and EVAR between 2009 and 2014. Ruptured and intact aneurysms were evaluated separately, and the analysis of intact aneurysms was limited to infrarenal AAAs. All 16 regions of the VQI were deidentified, and those with <100 open repairs were combined to eliminate the effect of low-volume regions. Regional variation was evaluated using χ2 and Fisher exact tests. Regional rates were compared against current quality benchmarks. RESULTS: Perioperative outcomes from 14 regions were compared. After open repair of intact aneurysms, no significant variation was seen in 30-day or in-hospital mortality; however, multiple regions exceeded the Society for Vascular Surgery benchmark for in-hospital mortality after open repair of intact aneurysms of <5% (range, 0%-7%; P = .55). After EVAR, all regions met the Society for Vascular Surgery benchmark of <3% (range, 0%-1%; P = .75). Significant variation in in-hospital mortality existed after open (14%-63%; P = .03) and endovascular (3%-32%; P = .03) repair of ruptured aneurysms across the VQI regional groups. After repair of intact aneurysms, wide variation was seen in prolonged length of stay (>7 days for open repair: 32%-53%, P = .54; >2 days for EVAR: 16-43%, P < .01), transfusion (open: 10%-35%, P < .01; EVAR: 7%-18%, P < .01), use of vasopressors (open: 19%-37%, P < .01; EVAR: 3%-7%, P < .01), and postoperative myocardial infarction (open: 0%-13%, P < .01; EVAR: 0%-3%, P < .01). After open repair, worsening renal function (6%-18%; P = .04) and respiratory complications (6%-20%; P = .20) were variable across regions. The frequency of endoleak at completion of EVAR also had considerable variation (15%-38%; P < .01). CONCLUSIONS: Despite limited variation, multiple regions do not meet current benchmarks for in-hospital mortality after open AAA repair for intact aneurysms. Significant regional variation exists in perioperative outcomes and length of stay, and mortality is widely variable after repair for rupture. These data identify important areas for quality improvement initiatives and clinical practice guidelines.

Clinical presentation, management, follow-up, and outcomes of isolated celiac and superior mesenteric artery dissections.

OBJECTIVE: Isolated visceral artery dissections are rare entities with no current consensus guidelines for treatment and follow-up. This study aims to evaluate the presentation, management, outcomes, and follow-up practices for patients with isolated visceral artery dissections and to compare those with and without symptoms. METHODS: In this retrospective analysis, we identified all patients with isolated celiac artery and/or isolated superior mesenteric artery dissections at a single institution between September 2006 and December 2014. Patients with concomitant aortic dissections were excluded. Cases were stratified by symptom status. Presentation, anatomic findings, treatment, outcomes, and follow-up imaging were then compared between symptomatic and asymptomatic patients. RESULTS: We identified 25 patients including 15 with symptoms and 10 without. There were no differences in patient comorbidities; however, symptomatic patients more frequently presented with thrombus (n = 10; 67% vs n = 1; 10%; P = .01) and inflammation (n = 8; 53% vs n = 1; 10%; P = .04), and trended toward increased stenosis (n = 12; 80% vs n = 4; 40%; P = .09) compared with asymptomatic patients. All asymptomatic patients were treated with observation alone with vessel diameter enlargement noted in 33% (n = 2) of patients on follow-up imaging. Among symptomatic patients, standard treatment included a short course of anticoagulation (mean, 4.5 months) with lifelong antiplatelet therapy. Three patients underwent operative intervention for persistent or worsening symptoms, two during the index admission and one 10 months after presentation for chronic abdominal pain. Approximately 70% (n = 17) of patients in each group had follow-up imaging (computed tomography angiography: n = 14; 56%; magnetic resonance angiography: n = 4; 16%; ultrasound: n = 13; 52%). Among patients treated nonoperatively, no patients complained of symptoms at follow-up, and 50% of those with inflammation on initial imaging had resolution. Twenty-five percent (n = 4) of patients had an increase in vessel size; however, all vessels remained less than 2 cm in maximal diameter. There were no ruptures or related deaths in either group. CONCLUSIONS: Among patients with visceral artery dissection, no ruptures occurred but diameter enlargement was documented. This disease progression suggests that routine surveillance may be appropriate; however, transitioning early to ultrasound imaging should be considered to decrease radiation, contrast, and associated costs.

Outcomes for symptomatic abdominal aortic aneurysms in the American College of Surgeons National Surgical Quality Improvement Program.

BACKGROUND: Historically, symptomatic abdominal aortic aneurysms (AAAs) were found to have intermediate mortality compared with asymptomatic and ruptured AAAs; but with wider use of endovascular aneurysm repair (EVAR), a more recent study suggested that mortality of symptomatic aneurysms was similar to that of asymptomatic AAAs. These prior studies were limited by small numbers. The purpose of this study was to evaluate the mortality and morbidity associated with symptomatic AAA repair in a large contemporary population. METHODS: All patients undergoing infrarenal AAA repair were identified in the 2011 to 2013 American College of Surgeons National Surgical Quality Improvement Program, vascular surgery targeted module. We excluded acute conversions to open repair and those for whom the surgical indication was embolization, dissection, thrombosis, or not documented. We compared 30-day mortality and major adverse events for asymptomatic, symptomatic, and ruptured AAA repair, stratified by EVAR and open repair, with univariate analysis and multivariable logistic regression. RESULTS: There were 5502 infrarenal AAAs identified, 4495 asymptomatic aneurysms (830 open repair, 3665 [82%] EVAR), 455 symptomatic aneurysms (143 open repair, 312 [69%] EVAR), and 552 ruptured aneurysms (263 open repair, 289 [52%] EVAR). Aneurysm diameter was similar between asymptomatic and symptomatic AAAs when stratified by procedure type, but it was larger for ruptured aneurysms (EVAR: symptomatic 5.8 ± 1.6 cm vs ruptured 7.5 ± 2.0 cm [P < .001]; open repair: symptomatic 6.4 ± 1.9 cm vs ruptured 8.0 ± 1.9 cm [P < .001]). The proportion of women was similar in symptomatic and ruptured AAAs (27% vs 23%, respectively; P = .14) but lower in asymptomatic AAAs (20%; P < .001). Symptomatic AAAs had intermediate 30-day mortality compared with asymptomatic and ruptured aneurysms after both EVAR (1.4% asymptomatic vs 3.8% symptomatic [P = .001]; symptomatic vs 22% ruptured [P < .001]) and open repair (4.3% asymptomatic vs 7.7% symptomatic [P = .08]; symptomatic vs 34% ruptured [P < .001]). After adjustment for age, gender, repair type, dialysis dependence, and history of severe chronic obstructive pulmonary disease, patients undergoing repair of symptomatic AAAs were twice as likely to die within 30 days compared with those with asymptomatic aneurysms (odds ratio [OR], 2.1; 95% confidence interval [CI], 1.3-3.5). When stratified by repair type, the effect size and direction of the ORs were similar (EVAR: OR, 2.4 [95% CI, 1.2-4.7]; open repair: OR, 1.8 [95% CI, 0.86-3.9]) although not significant for open repair. Patients with ruptured aneurysms had a sevenfold increased risk of 30-day mortality compared with symptomatic patients (OR, 6.5; 95% CI, 4.1-10.6). CONCLUSIONS: Patients with symptomatic AAAs had a twofold increased risk of perioperative mortality compared with patients with asymptomatic aneurysms undergoing repair. Furthermore, patients with ruptured aneurysms have a sevenfold increased risk of mortality compared with patients with symptomatic aneurysms.

Regional variation exists in patient selection and treatment of abdominal aortic aneurysms.

OBJECTIVE: Significant regional variation in surgical rates has been identified following multiple surgical procedures. However, limited data have examined the regional variability in patient selection and treatment of abdominal aortic aneurysms (AAAs). This study aimed to evaluate regional variation in patient selection, perioperative management, and operative approach for the repair of AAAs. METHODS: All patients undergoing open repair or endovascular aneurysm repair (EVAR) of an AAA in the Vascular Quality Initiative from 2009 to 2014 were identified. All regional groups were deidentified, and those with fewer than 100 open repairs were combined into a single region. RESULTS: We identified 17,269 elective repairs (EVAR, 13,759; open, 3510) and 1462 ruptured AAAs (EVAR, 749; open, 713). There was significant regional variation in the use of EVAR for elective repair (range, 66%-88%; P < .01) and ruptured AAA repair (40%-80%; P < .01). The median diameter for elective repair was similar among regions (EVAR, 5.4 cm; open, 5.7 cm). There was wide variation in the treatment of small aneurysms in male patients (<5.5 cm) for EVAR (34%-49%; P < .01) and open repair (17%-38%; P < .01) and variation in the treatment of small aneurysms in female patients (<5 cm) for EVAR (14%-32%; P < .01) but not significant for open repair (6%-24%). For elective cases, preoperative aspirin (EVAR, 50%-75% [P < .01]; open, 49%-78% [P < .01]) and statin use (EVAR, 61%-75% [P < .01]; open, 56%-80% [P < .01]) varied widely. Among elective cardiac patients, preoperative management varied significantly, including beta-blocker use (EVAR, 66%-78% [P < .01]; open, 69%-88% [P = .01]) and the frequency of stress tests (EVAR, 33%-64% [P < .01]; open, 31%-73% [P < .01]). Among open repairs for aneurysms extending at or beyond the juxtarenal segment, there was wide variation in the use of retroperitoneal exposures (7%-70%; P < .01) and adjunctive renal protective measures (cold renal perfusion, 2%-43% [P < .01]; mannitol, 47%-92% [P < .01]). CONCLUSIONS: Significant regional variation exists in patient selection, perioperative management, and operative approach for the repair of AAA. Definitive evidence is lacking in many aspects of operative care, including the use of the retroperitoneal approach and renal protective strategies. However, this variation emphasizes the importance of research to determine best practice in the areas of greatest variation. Furthermore, where current clinical process measures exist and data are clear, such as the use of statin and antiplatelet agents, the high degree of variation should serve as an impetus for regional quality improvement projects.

Transperitoneal versus retroperitoneal approach for open abdominal aortic aneurysm repair in the targeted vascular National Surgical Quality Improvement Program.

OBJECTIVE: We sought to compare current practices in patient selection and 30-day outcomes for transperitoneal and retroperitoneal abdominal aortic aneurysm (AAA) repairs. METHODS: All patients undergoing elective transperitoneal or retroperitoneal surgical repair for AAA between January 2011 and December 2013 were identified in the Targeted Vascular National Surgical Quality Improvement Program database. Emergency cases were excluded. Baseline characteristics, anatomic details, and intraoperative and postoperative outcomes were evaluated among those with infrarenal or juxtarenal AAA only. RESULTS: We identified 1135 patients: 788 transperitoneal (69%) and 347 retroperitoneal (31%). When only infrarenal and juxtarenal AAAs were evaluated, the retroperitoneal patients were less likely to have an infrarenal clamp location (43% vs 68%) and had more renal revascularizations (15% vs 6%; P < .001), more visceral revascularizations (5.6% vs 2.4%; P = .014), and more lower extremity revascularizations (11% vs 7%; P = .021) compared with the transperitoneal approach. Postoperative mortality and return to the operating room were similar. Transperitoneal patients had a higher rate of wound dehiscence (2.4% vs 0.4%; P = .045), and retroperitoneal patients had higher incidence of pneumonia (9% vs 5%; P = .034), transfusion (77% vs 71%; P = .037), and reintubation (11% vs 7%; P = .034), and a longer median length of stay (8 vs 7 days; P = .048). After exclusion of all concomitant procedures, only transfusions remained more common in the retroperitoneal approach (78% vs 70%; P = .036). Multivariable analyses showed only higher rates of reintubation in the retroperitoneal group (odds ratio, 1.7; 95% confidence interval, 1.0-3.0; P = .047). CONCLUSIONS: The retroperitoneal approach is more commonly used for more proximal aneurysms and was associated with higher rates of pneumonia, reintubation, and transfusion, and a longer length of stay on univariate analyses. However, multivariable analysis demonstrated similar results between groups. The long-term benefits and frequency of reinterventions remain to be proven.

Risk factors and consequences of persistent type II endoleaks.

OBJECTIVE: Type II endoleaks are common after endovascular aneurysm repair (EVAR), but their clinical significance remains undefined and their management controversial. We determined risk factors for type II endoleaks and associations with adverse outcomes. METHODS: We identified all EVAR patients in the Vascular Study Group of New England abdominal aortic aneurysm database. Patients were subdivided into two groups: (1) those with no endoleak or transient type II endoleak and (2) persistent type II endoleak or new type II endoleak (no endoleak at completion of case). Patients with other endoleak types and follow-up shorter than 6 months were excluded. Multivariable analysis was used to evaluate predictors of persistent or new type II endoleaks. Kaplan-Meier and Cox regression analysis were used to evaluate predictors of reintervention and survival. RESULTS: Two thousand three hundred sixty-seven EVAR patients had information on endoleaks: 1977 (84%) were in group 1, of which 79% had no endoleaks at all, and 21% had transient endoleaks that resolved at follow-up. The other 390 (16%) were in group 2, of which 31% had a persistent leak, and 69% had a new leak at follow-up that was not seen at the time of surgery. Group 2 was older (mean age, 75 vs 73 years; P < .001) and less likely to have chronic obstructive pulmonary disease (COPD; 24% vs 34%; P < .001) or elevated creatinine levels (2.6% vs 5.3%; P = .027). Coil embolization of one or both hypogastric arteries was associated with a higher rate of persistent type II endoleaks (12 vs 8%; P = .024), as was distal graft extension (12% vs 8%; P = .008). In multivariable analysis, COPD (odds ratio [OR], 0.7; 95% confidence interval [CI], 0.5-0.9; P = .017) was protective against persistent type II endoleak, while hypogastric artery coil embolization (OR, 1.5; 95% CI, 1.0-2.2; P = .044), distal graft extension (OR, 1.6; 95% CI, 1.1-2.3; P = .025), and age ≥ 80 (OR, 2.7; 95% CI, 1.4-5.3; P = .004) were predictive. Graft type was also associated with endoleak development. Persistent type II endoleaks were predictive of postdischarge reintervention (OR, 15.3; 95% CI, 9.7-24.3; P < .001); however, they were not predictive of long-term survival (OR, 1.1; 95% CI, 0.9-1.6; P = .477). CONCLUSIONS: Persistent type II endoleak is associated with hypogastric artery coil embolization, distal graft extension, older age, the absence of COPD, and graft type, but not with aneurysm size. Persistent type II endoleaks are associated with an increased risk of reinterventions, but not rupture or survival. This reinforces the need for continued surveillance of patients with persistent type II endoleaks and the importance of follow-up to detect new type II endoleaks over time.

Increased preoperative pulse pressure predicts procedural complications and mortality in patients who undergo tibial interventions for critical limb ischemia.

BACKGROUND: Pulse pressure is a noninvasive measure of arterial stiffness. Increased pulse pressure is associated with an increased risk of cardiovascular events and death. The effects of pulse pressure on outcomes after endovascular interventions for critical limb ischemia (CLI), however, are unknown. We thus evaluated whether increased preoperative pulse pressure was associated with adverse outcomes and mortality in patients who underwent endovascular tibial artery intervention. METHODS: All patients who underwent endovascular tibial intervention for CLI at a single institution from 2004 to 2014 were included in this study. Preoperative pulse pressure was derived from measurements obtained in the holding area before the procedure. Patients were divided into two groups on the basis of pulse pressure, <80 or ≥80 mm Hg. Patient demographic characteristics and comorbidities were documented, and outcomes including procedural complications, repeat intervention, amputation, and mortality were recorded. Multivariable logistic regression was used to account for patient demographic characteristics and comorbidities. RESULTS: Of 371 patients, 186 patients had a preoperative pulse pressure <80 mm Hg and 185 had a preoperative pulse pressure ≥80 mm Hg. No significant differences in patient demographic characteristics or comorbidities were identified; however, there was a trend toward older age in patients with increased pulse pressure (70 vs 72; P = .07). In univariate analysis, procedural complications (21% vs 13%; P = .02), reinterventions (26% vs 17%; P < .01), and restenosis (32% vs 23%; P = .03) were more common among patients with pulse pressure ≥80. Procedural complications remained significant in multivariate analysis (odds ratio, 1.8; 95% confidence interval, 1.0-3.1; P = .04). There was no difference in 30-day mortality; however, increased mortality was seen at 5 years of follow-up (odds ratio, 1.6; 95% confidence interval, 1.0-2.5; P = .04) in multivariable analysis. CONCLUSIONS: Increased preoperative pulse pressure is associated with procedural complications and increased mortality in patients who undergo endovascular tibial intervention for CLI. It is a marker of increased risk, and might be a suitable target for interventions aimed at improving outcomes in this high-risk population.

Management and outcomes of isolated renal artery aneurysms in the endovascular era.

OBJECTIVE: Isolated renal artery aneurysms are rare, and controversy remains about indications for surgical repair. Little is known about the impact of endovascular therapy on selection of patients and outcomes of renal artery aneurysms. METHODS: We identified all patients undergoing open or endovascular repair of isolated renal artery aneurysms in the Nationwide Inpatient Sample from 1988 to 2011 for epidemiologic analysis. Elective cases were selected from the period 2000 to 2011 to create comparable cohorts for outcome comparison. We identified all patients with a primary diagnosis of renal artery aneurysms undergoing open surgery (reconstruction or nephrectomy) or endovascular repair (coil or stent). Patients with concomitant aortic aneurysms or dissections were excluded. We evaluated patient characteristics, management, and in-hospital outcomes for open and endovascular repair, and we examined changes in management and outcomes over time. RESULTS: We identified 6234 renal artery aneurysm repairs between 1988 and 2011. Total repairs increased after the introduction of endovascular repair (8.4 in 1988 to 13.8 in 2011 per 10 million U.S. population; P = .03). Endovascular repair increased from 0 in 1988 to 6.4 in 2011 per 10 million U.S. population (P < .0001). However, there was no concomitant decrease in open surgery (5.5 in 1988 to 7.4 in 2011 per 10 million U.S. population; P = .28). From 2000 to 2011, there were 1627 open and 1082 endovascular elective repairs. Patients undergoing endovascular repair were more likely to have a history of coronary artery disease (18% vs 11%; P < .001), prior myocardial infarction (5.2% vs 1.8%; P < .001), and renal failure (7.7% vs 3.3%; P < .001). In-hospital mortality was 1.8% for endovascular repair, 0.9% for open reconstruction (P = .037), and 5.4% for nephrectomy (P < .001 compared with all revascularization). Complication rates were 12.4% for open repair vs 10.5% for endovascular repair (P = .134), including more cardiac (2.2% vs 0.6%; P = .001) and peripheral vascular complications (0.6% vs 0.0%; P = .014) with open repair. Open repair had a longer length of stay (6.0 vs 4.6 days; P < .001). After adjustment for other predictors of mortality, including age (odds ratio [OR], 1.05 per decade; 95% confidence interval [CI], 1.0-1.1; P = .001), heart failure (OR, 7.0; 95% CI, 3.1-16.0; P < .001), and dysrhythmia (OR, 5.9; 95% CI, 2.0-16.8; P = .005), endovascular repair was still not protective (OR, 1.6; 95% CI, 0.8-3.2; P = .145). CONCLUSIONS: More renal artery aneurysms are being treated with the advent of endovascular techniques, without a reduction in operative mortality or a reduction in open surgery. Indications for repair of renal artery aneurysms should be re-evaluated.

Long-Term Outcomes of Abdominal Aortic Aneurysm in the Medicare Population.

BACKGROUND: Randomized trials and observational studies have shown that perioperative morbidity and mortality are lower with endovascular repair of abdominal aortic aneurysm than with open repair, but the survival benefit is not sustained. In addition, concerns have been raised about the long-term risk of aneurysm rupture or the need for reintervention after endovascular repair. METHODS: We assessed perioperative and long-term survival, reinterventions, and complications after endovascular repair as compared with open repair of abdominal aortic aneurysm in propensity-score-matched cohorts of Medicare beneficiaries who underwent repair during the period from 2001 through 2008 and were followed through 2009. RESULTS: We identified 39,966 matched pairs of patients who had undergone either open repair or endovascular repair. The overall perioperative mortality was 1.6% with endovascular repair versus 5.2% with open repair (P<0.001). From 2001 through 2008, perioperative mortality decreased by 0.8 percentage points among patients who underwent endovascular repair (P=0.001) and by 0.6 percentage points among patients who underwent open repair (P=0.01). The rate of conversion from endovascular to open repair decreased from 2.2% in 2001 to 0.3% in 2008 (P<0.001). The rate of survival was significantly higher after endovascular repair than after open repair through the first 3 years of follow-up, after which time the rates of survival were similar. Through 8 years of follow-up, interventions related to the management of the aneurysm or its complications were more common after endovascular repair, whereas interventions for complications related to laparotomy were more common after open repair. Aneurysm rupture occurred in 5.4% of patients after endovascular repair versus 1.4% of patients after open repair through 8 years of follow-up (P<0.001). The rate of total reinterventions at 2 years after endovascular repair decreased over time (from 10.4% among patients who underwent procedures in 2001 to 9.1% among patients who underwent procedures in 2007). CONCLUSIONS: Endovascular repair, as compared with open repair, of abdominal aortic aneurysm was associated with a substantial early survival advantage that gradually decreased over time. The rate of late rupture was significantly higher after endovascular repair than after open repair. The outcomes of endovascular repair have been improving over time. (Funded by the National Institutes of Health.).

The effect of endovascular treatment on isolated iliac artery aneurysm treatment and mortality.

OBJECTIVE: Isolated iliac artery aneurysms are rare, but potentially fatal. The effect of recent trends in the use of endovascular iliac aneurysm repair (EVIR) on isolated iliac artery aneurysm-associated mortality is unknown. METHODS: We identified all patients with a primary diagnosis of iliac artery aneurysm in the National Inpatient Sample from 1988 to 2011. We examined trends in management (open vs EVIR, elective and urgent) and overall isolated iliac artery aneurysm-related deaths (with or without repair). We compared in-hospital mortality and complications for the subgroup of patients undergoing elective open and EVIR from 2000 to 2011. RESULTS: We identified 33,161 patients undergoing isolated iliac artery aneurysm repair from 1988 to 2011, of which there were 9016 EVIR and 4933 open elective repairs from 2000 to 2011. Total repairs increased after the introduction of EVIR, from 28 to 71 per 10 million United States (U.S.) population (P < .001). EVIR surpassed open repair in 2003. Total isolated iliac artery aneurysm-related deaths, due to rupture or elective repair, decreased after the introduction of EVIR from 4.4 to 2.3 per 10 million U.S. population (P < .001). However, urgent admissions did not decrease during this time period (15 to 15 procedures per 10 million U.S. population; P = .30). Among elective repairs after 2000, EVIR patients were older (72.4 vs 69.4 years; P = .002) and were more likely to have a history of prior myocardial infarction (14.0% vs 11.3%; P < .001) and renal failure (7.2% vs 3.6%; P < .001). Open repair had significantly higher rate of in-hospital mortality (1.8% vs 0.5%; P < .001) and complications (17.9% vs 6.7%; P < .001) and a longer length of stay (6.7 vs 2.3 days; P < .001). CONCLUSIONS: Treatment of isolated iliac artery aneurysms has increased since the introduction of EVIR and is associated with lower perioperative mortality, despite a higher burden of comorbid illness. Decreasing iliac artery aneurysm-attributable in-hospital deaths are likely related primarily to lower elective mortality with EVIR rather than rupture prevention.

The impact of endovascular repair on specialties performing abdominal aortic aneurysm repair.

BACKGROUND: Abdominal aortic aneurysm (AAA) repair has been performed by various surgical specialties for many years. Endovascular aneurysm repair (EVAR) may be a disruptive technology, having an impact on which specialties care for patients with AAA. Therefore, we examined the proportion of AAA repairs performed by various specialties over time in the United States and evaluated the impact of the introduction of EVAR. METHODS: The Nationwide Inpatient Sample (2001-2009) was queried for intact and ruptured AAA and for open repair and EVAR. Specific procedures were used to identify vascular surgeons (VSs), cardiac surgeons (CSs), and general surgeons (GSs) as well as interventional cardiologists and interventional radiologists for states that reported unique treating physician identifiers. Annual procedure volumes were subsequently calculated for each specialty. RESULTS: We identified 108,587 EVARs and 85,080 open AAA repairs (3011 EVARs and 12,811 open repairs for ruptured AAA). VSs performed an increasing proportion of AAA repairs during the study period (52% in 2001 to 66% in 2009; P < .001). GSs and CSs performed fewer repairs during the same period (25% to 17% [P < .001] and 19% to 13% [P < .001], respectively). EVAR was increasingly used for intact (33% to 78% of annual cases; P < .001) as well as ruptured AAA repair (5% to 28%; P < .001). The proportion of intact open repairs performed by VSs increased from 52% to 65% (P < .001), whereas for EVAR, the proportion went from 60% to 67% (P < .001). The proportion performed by VSs increased for ruptured open repairs from 37% to 53% (P < .001) and for ruptured EVARs from 28% to 73% (P < .001). Compared with treatment by VSs, treatment by a CS (0.55 [0.53-0.56]) and GS (0.66 [0.64-0.68]) was associated with a decreased likelihood of undergoing endovascular rather than open AAA repair. CONCLUSIONS: VSs are performing an increasing majority of AAA repairs, in large part driven by the increased utilization of EVAR for both intact and ruptured AAA repair. However, GSs and CSs still perform AAA repair. Further studies should examine the implications of these national trends on the outcome of AAA repair.

Percutaneous versus femoral cutdown access for endovascular aneurysm repair.

OBJECTIVE: Prior studies suggest that percutaneous access for endovascular abdominal aortic aneurysm repair (pEVAR) offers significant operative and postoperative benefits compared with femoral cutdown (cEVAR). National data on this topic, however, are limited. We compared patient selection and outcomes for elective pEVAR and cEVAR. METHODS: We identified all patients undergoing either pEVAR (bilateral percutaneous access, whether successful or not) or cEVAR (at least one planned groin cutdown) for abdominal aortic aneurysms from January 2011 to December 2013 in the Targeted Vascular data set from the American College of Surgeons National Surgical Quality Improvement Program database. Emergent cases, ruptures, cases with an iliac conduit, and cases with a preoperative wound infection were excluded. Groups were compared by χ(2) test or t-test or the Mann-Whitney test where appropriate. RESULTS: We identified 4112 patients undergoing elective EVAR, 3004 cEVAR patients (73%) and 1108 pEVAR patients (27%). Of all EVAR patients, 26% had bilateral percutaneous access; 1.0% had attempted percutaneous access converted to cutdown (4% of pEVARs); and the remainder had a planned cutdown, 63.9% bilateral and 9.1% unilateral. There were no significant differences in age, gender, aneurysm diameter, or prior open abdominal surgery. Patients undergoing cEVAR were less likely to have congestive heart failure (1.5% vs 2.4%; P = .04) but more likely to undergo any concomitant procedure during surgery (32% vs 26%; P < .01) than patients undergoing pEVAR. Postoperatively, pEVAR patients had shorter operative time (mean, 135 vs 152 minutes; P < .01), shorter length of stay (median, 1 day vs 2 days; P < .01), and fewer wound complications (2.1% vs 1.0%; P = .02). On multivariable analysis, the only predictor of percutaneous access failure was performance of any concomitant procedure (odds ratio, 2.0; 95% confidence interval, 1.0-4.0; P = .04). CONCLUSIONS: Currently, one in four patients treated at Targeted Vascular National Surgical Quality Improvement Program centers are getting pEVAR, which is associated with a high success rate, shorter operation time, shorter length of stay, and fewer wound complications compared with cEVAR.

Risk factors and indications for readmission after lower extremity amputation in the American College of Surgeons National Surgical Quality Improvement Program.

BACKGROUND: Postoperative readmission, recently identified as a marker of hospital quality in the Affordable Care Act, is associated with increased morbidity, mortality, and health care costs, yet data on readmission after lower extremity amputation (LEA) are limited. We evaluated risk factors for readmission and postdischarge adverse events after LEA in the American College of Surgeons National Surgical Quality Improvement Program (NSQIP). METHODS: All patients undergoing transmetatarsal (TMA), below-knee (BKA), or above-knee amputation (AKA) in the 2011-2012 NSQIP were identified. Independent predischarge predictors of 30-day readmission were determined by multivariable logistic regression. Readmission indication and reinterventions, available in the 2012 NSQIP only, were also evaluated. RESULTS: We identified 5732 patients undergoing amputation (TMA, 12%; BKA, 51%; AKA, 37%). Readmission rate was 18%. Postdischarge mortality rate was 5% (TMA, 2%; BKA, 3%; AKA, 8%; P < .001). Overall complication rate was 43% (in-hospital, 32%; postdischarge, 11%). Reoperation was for wound-related complication or additional amputation in 79% of cases. Independent predictors of readmission included chronic nursing home residence (odds ratio [OR], 1.3; 95% confidence interval [CI], 1.0-1.7), nonelective surgery (OR, 1.4; 95% CI, 1.1-1.7), prior revascularization/amputation (OR, 1.4; 95% CI, 1.1-1.7), preoperative congestive heart failure (OR, 1.7; 95% CI, 1.2-2.4), and preoperative dialysis (OR, 1.5; 95% CI, 1.2-1.9). Guillotine amputation (OR, 0.6; 95% CI, 0.4-0.9) and non-home discharge (OR, 0.7; 95% CI, 0.6-1.0) were protective of readmission. Wound-related complications accounted for 49% of readmissions. CONCLUSIONS: Postdischarge morbidity, mortality, and readmission are common after LEA. Closer follow-up of high-risk patients, optimization of medical comorbidities, and aggressive management of wound infection may play a role in decreasing readmission and postdischarge adverse events.

Endovascular treatment of abdominal aortic aneurysms.

Patients with abdominal aortic aneurysms (AAAs) are usually treated with endovascular aneurysm repair (EVAR), which has become the standard of care in many hospitals for patients with suitable anatomy. Clinical evidence indicates that EVAR is associated with superior perioperative outcomes and similar long-term survival compared with open repair. Since the randomized, controlled trials that provided this evidence were conducted, however, the stent graft technology for infrarenal AAA has been further developed. Improvements include profile downsizing, optimization of sealing and fixation, and the use of low porosity fabrics. In addition, imaging techniques have improved, enabling better preoperative planning, stent graft placement, and postoperative surveillance. Also in the past few years, fenestrated and branched stent grafts have increasingly been used to manage anatomically challenging aneurysms, and experiments with off-label use of stent grafts have been performed to treat patients deemed unfit or unsuitable for other treatment strategies. Overall, the indications for endovascular management of AAA are expanding to include increasingly complex and anatomically challenging aneurysms. Ongoing studies and optimization of imaging, in addition to technological refinement of stent grafts, will hopefully continue to broaden the utilization of EVAR.