Shankha Mukhopadhyay

A propensity-matched comparison of outcomes for fenestrated endovascular aneurysm repair and open surgical repair of complex abdominal aortic aneurysms

OBJECTIVE The benefit of fenestrated endovascular aortic aneurysm repair (FEVAR) compared with open surgical repair (OSR) of complex abdominal aortic aneurysms (CAAAs) is unknown. This study compares 30-day outcomes of these procedures from two high-volume centers where FEVAR was undertaken for high-risk patients. METHODS Patients undergoing FEVAR with commercially available devices and OSR of CAAAs (total suprarenal/supravisceral clamp position) were propensity matched by demographic, clinical, and anatomic criteria to identify similar patient cohorts. Perioperative outcomes were evaluated using univariate and multivariate methods. RESULTS From July 2001 to August 2012, 59 FEVAR and 324 OSR patients were identified. After 1:4 propensity matching for age, gender, hypertension, congestive heart failure, coronary disease, chronic obstructive pulmonary disease, stroke, diabetes, preoperative creatinine, and anticipated/actual aortic clamp site, the study cohort consisted of 42 FEVARs and 147 OSRs. The most frequent FEVAR construct was two renal fenestrations, with or without a single mesenteric scallop, in 50% of cases. An average of 2.9 vessels were treated per patient. Univariate analysis demonstrated FEVAR had higher rates of 30-day mortality (9.5% vs. 2%; P = .05), any complication (41% vs. 23%; P = .01), procedural complications (24% vs. 7%; P < .01), and graft complications (30% vs. 2%; P < .01). Multivariable analysis showed FEVAR was associated with an increased risk of 30-day mortality (odds ratio [OR], 5.1; 95% confidence interval [CI], 1.1-24; P = .04), any complication (OR, 2.3; 95% CI, 1.1-4.9; P = .01), and graft complications (OR, 24; 95% CI, 4.8-66; P < .01). CONCLUSIONS FEVAR, in this two-center study, was associated with a significantly higher risk of perioperative mortality and morbidity compared with OSR for management of CAAAs. These data suggest that extension of the paradigm shift comparing EVAR with OSR for routine AAAs to patients with CAAAs is not appropriate. Further study to establish proper patient selection for FEVAR instead of OSR is warranted before widespread use should be considered.

Impact of chronic kidney disease on outcomes after abdominal aortic aneurysm repair

OBJECTIVE Chronic kidney disease (CKD) is associated with increased morbidity and death after open abdominal aortic aneurysm (AAA) repair (OAR). This study highlights the effect of CKD on outcomes after endovascular AAA (EVAR) and OAR in contemporary practice. METHODS The National Surgical Quality Improvement Program (NSQIP) Participant Use File (2005-2008) was queried by Current Procedural Terminology (American Medical Association, Chicago, Ill) code to identify EVAR or OAR patients, who were grouped by CKD class as having mild (CKD class 1 or 2), moderate (CKD class 3), or severe (CKD class 4 or 5) renal disease. Propensity score analysis was performed to match OAR and EVAR patients with mild CKD with those with moderate or severe CKD. Comparative analysis of mortality and clinical outcomes was performed based on CKD strata. RESULTS We identified 8701 patients who were treated with EVAR (n = 5811) or OAR (n = 2890) of intact AAAs. Mild, moderate, and severe CKD was present in 63%, 30%, and 7%, respectively. CKD increased (P < .01) overall mortality, with rates of 1.7% (mild), 5.3% (moderate), and 7.7% (severe) in unmatched patients undergoing EVAR or OAR. Operative mortality rates in patients with severe CKD were as high as 6.2% for EVAR and 10.3% for OAR. Severity of CKD was associated with increasing frequency of risk factors; therefore, propensity matching to control for comorbidities was performed, resulting in similar baseline clinical and demographic features of patients with mild compared with those with moderate or severe disease. In propensity-matched cohorts, moderate CKD increased the risk of 30-day mortality for EVAR (1.9% mild vs 3.2% moderate; P = .013) and OAR (3.1% mild vs 8.4% moderate; P < .0001). Moderate CKD was also associated with increased morbidity in patients treated with EVAR (8.3% mild vs 12.8% moderate; P < .0001) or OAR (25.2% mild vs 32.4% moderate; P = .001). Similarly, severe CKD increased the risk of 30-day mortality for EVAR (2.6% mild vs 5.7% severe; P = .0081) and OAR (4.1% mild vs 9.9% severe; P = .0057). Severe CKD was also associated with increased morbidity in patients treated with EVAR (10.6% mild vs 19.2% severe; P < .0001) or OAR (31.1% mild vs 39.6% severe; P = .04). CONCLUSIONS The presence of moderate or severe CKD in patients considered for AAA repair is associated with significantly increased mortality and therefore should figure prominently in clinical decision making. The high mortality of AAA repair in patients with severe CKD is such that elective repair in such patients is not advised, except in extenuating clinical circumstances.

Progression of asymptomatic carotid stenosis despite optimal medical therapy

BACKGROUND Despite level 1 evidence in support of carotid endarterectomy vs medical therapy in selected asymptomatic patients, an alternative posture is that optimal medical therapy (OMT) has not been adequately studied and that such OMT has reduced stroke risk in asymptomatic patients to levels wherein carotid endarterectomy is no longer justified. The goal of this study was to determine the natural history of patients with asymptomatic moderate (50%-69%) carotid artery stenosis (AMCAS) in a contemporary cohort as a function of their associated medical therapy. METHODS Patients with AMCAS determined by duplex ultrasound (DUS) from 2005-2006 were identified in our hospital database. Patients were included in the cohort if they had at least one additional DUS during the 6-year follow-up interval. Patient characteristics including medication history and lipid levels were collected. Patients were considered to have OMT if they were on aspirin and a statin with a low-density lipoprotein level that was always <100 mg/dL. Study end points included progression of carotid disease by DUS to severe stenosis (70%-100%), development of ipsilateral neurologic symptoms (INS) such as stroke or transient ischemic attack, and death. RESULTS There were 900 carotid arteries in 794 patients in the study cohort. The average age was 72.5 years, 77.2% had hypertension, 59.6% had coronary artery disease, and 87.1% were on a statin throughout the study. The low-density lipoprotein cholesterol level was always normal (<100 mg/dL) in 37.8% and accordingly, 241 (30.3%) had OMT as defined above. The 5-year actuarial survival was 81.9% ± 1.3% with no advantage seen with OMT. Multivariate analysis of survival showed statins were protective (hazard ratio [HR], 0.50; confidence interval [CI], 0.34-0.73; P = .0004). The 5-year freedom from plaque progression was 61.2% ± 2.1% with no benefit from OMT vs the control group. Multivariate predictors of plaque progression were chronic kidney disease (HR, 2.1; CI, 1.2-3.7; P = .009), aspirin use (HR, 1.9; CI, 1.2-3.0; P = .01), and the use of calcium channel blockers (HR, 1.4; CI, 1.1-1.8; P = .007). There were 90 (11.3%) patients who developed INS during follow-up (58% of these were strokes), and the 5-year freedom from INS was 88.4% ± 1.5%. Multivariate predictors of INS were diabetes (HR, 2.3; CI, 1.5-3.6; P = .0002) and warfarin use (HR, 1.9; CI, 1.2-2.9; P = .009); while statin use (HR, 0.37; CI, 0.22-0.65; P = .0005) was protective against symptom development. CONCLUSIONS At the 5-year of follow-up, OMT failed to prevent carotid disease progression or development of ipsilateral symptoms in 45% of patients with AMCAS.

Impact of severe chronic kidney disease on outcomes of infrainguinal peripheral arterial intervention

OBJECTIVE Patients with severe chronic kidney disease (CKD) and peripheral vascular disease are at increased risk of major adverse limb events (MALEs) and death; however, patients with end-stage renal disease have been excluded in current objective performance goals. We evaluated the effect of severe (class 4 and 5) CKD on outcomes after infrainguinal endovascular arterial interventions. METHODS All primary peripheral vascular interventions (PVIs) performed at a single institution (January 2002 through December 2009) were included. End points were defined by Society for Vascular Surgery objective performance goals for critical limb ischemia (CLI), which include all-cause mortality, reintervention, and composite end points of death or amputation and MALEs (reintervention or amputation). Univariate and multivariable analysis was used to examine the effect of severe CKD on study end points. RESULTS A total of 879 PVIs were performed, with severe CKD in 125 (14%). Severe CKD patients were significantly (P < .05) more likely to have diabetes (64% vs 46%), CLI (72% vs 11%), and need a multilevel PVI (34% vs 19%) or tibial intervention (35% vs 20%) compared with the remainder of the cohort. Distribution of TransAtlantic Inter-Society Consensus C and D lesions were similar (19% severe CKD vs 15%; P = .2). Severe CKD predicted perioperative (30-day) reintervention (odds ratio [OR], 2.3; 95% confidence interval [CI], 1.5-4; P = .05), amputation or death (OR, 3.1; 95% CI, 1.1-9; P = .04), and MALEs (OR, 2.8; 95% CI, 1.3-6.1; P = .04), which was independent of CLI in multivariable regression analysis. On Kaplan-Meier analysis, severe CKD was significantly (log-rank P < .05) associated with death (31% ± 4% vs 7% ± 1%), amputation (14% ± 3% vs 3% ± 1%), and MALEs (40% ± 5% vs 26% ± 2%) at 1 year. Freedom from reintervention was similar at 1 year (70% ± 5% severe CKD vs 75% ± 2%; P = .23). Risk-adjusted (age, CLI, diabetes, coronary artery disease) Cox proportional hazards regression showed that severe CKD increased the risk of late mortality (hazard ratio [HR], 2.4; 95% CI, 1.8-3.2; P < .01), amputation (HR, 2.1; 95% CI, 1.1-3.9; P = .02), and death or amputation (HR, 1.8; 95% CI, 1.3-2.4; P = .04), without increasing the risk of late reinterventions or MALEs. CONCLUSIONS CKD independently predicts early and late adverse events after a PVI, in particular, excessive mortality. CKD should figure prominently in clinical decision making for patients with peripheral vascular disease.

Clinical and anatomic outcomes after carotid endarterectomy

OBJECTIVE The purpose of this study was to examine 30-day and long-term outcomes after carotid endarterectomy (CEA) in a contemporary series and to identify variables associated with stroke and death after CEA. METHODS This was a retrospective review of patients undergoing an isolated CEA at a single institution between January 1989 and December 2005. Primary study end points were 30-day and long-term overall stroke, ipsilateral stroke, and death. Secondary end points were recurrent stenosis (>70% stenosis) and reintervention. Kaplan-Meier analysis was used to create survival curves for the long-term study end points. Multivariate models were created to identify variables associated with the study end points. RESULTS During the study period, 3014 CEAs were performed on 2644 patients (mean age, 71.0 ± 8.9 years; 60.9% male; 33.5% symptomatic; 37% primary closure), with mean follow-up of 7.0 years. The 30-day ipsilateral stroke, death, and combined ipsilateral stroke/death rates were 1.3%, 1.1%, and 2.2%, respectively. Previous ipsilateral CEA or neck dissection for cancer (hazard ratio [HR], 3.68; P = .0081) and symptomatic disease (HR, 2.45; P = .0071) were predictive of 30-day ipsilateral stroke. Stroke-free survival was 93.8% at 4 years and 86.9% at 10 years. Diabetes (HR, 1.94; P < .0001), symptomatic disease (HR, 1.75; P < .0001), female gender (HR, 1.34; P = .035), and increasing age (HR, 1.02; P < .0001) were predictors of long-term overall stroke. Ipsilateral stroke-free survival was 97.6% at 5 years and 94.6% at 10 years, respectively. Contralateral occlusion (HR, 2.06; P = .025) and symptomatic disease (HR, 1.87; P = .003) were predictors of ipsilateral stroke, whereas antilipid therapy was protective (HR, 0.65; P = .049). Overall survival was 70.1% at 5 years and 42.2% at 10 years, with no difference between symptomatic and asymptomatic patients. Although a variety of comorbidities were associated with inferior late survival, as anticipated, female gender (HR, 0.89; P = .016) and lipid-lowering therapy (HR, 0.69; P < .0001) were protective. Reintervention was 3.4% at 5 years and 6.6% at 10 years, with primary closure (vs patch angioplasty/eversion) increasing the risk of reintervention (HR, 1.72; P = .007). CONCLUSIONS CEA has favorable perioperative and long-term clinical and anatomic outcomes with respect to its goal of stroke prevention for symptomatic and asymptomatic patients. Adjuvant medical therapy (antilipid) has increased overall and ipsilateral stroke-free survival.

Impact of hospital volume and type on outcomes of open and endovascular repair of descending thoracic aneurysms in the United States Medicare population.

OBJECTIVE Favorable outcomes of thoracic endovascular aortic repair (TEVAR) compared with open repair for descending thoracic aortic aneurysms (DTAs) have led to increasing TEVAR use. We evaluated the effect of case volume and hospital teaching status on clinical outcomes of intact DTA repair. METHODS The Medicare Provider Analysis and Review (MEDPAR) data set (2004 to 2007) was queried to identify open repair or TEVAR for DTA. Hospitals were stratified by DTA volume into high volume (HV; ≥ 8 cases/y) or low volume (LV; <8 cases/y) and teaching or nonteaching. The effect of hospital variables on the primary study end point of 30-day mortality and secondary end points of 30-day complications and long-term survival after open repair and TEVAR DTA repair were studied using univariate testing, multivariable regression modeling, Kaplan-Meier survival analysis, and Cox proportional hazards regression modeling. RESULTS We identified 763 hospitals performing 3554 open repairs and 3517 TEVARs. Overall DTA repair increased (P < .01) from 1375 in 2004 to 1987 in 2007. The proportion of hospitals performing open repair significantly decreased from 95% in 2004 to 57% in 2007 (P < .01), whereas those performing TEVAR increased (P < .01) from 24% to 76%. Overall repair type shifted from open (74% in 2004, the year before initial commercial availability of TEVAR) to TEVAR (39% open in 2007; P < .01). The fraction of open repairs at LV hospitals decreased from 56% in 2004 to 44% in 2007 (P < .01), whereas TEVAR increased from 24% in 2004 to 51% in 2007 (P < .01). Overall mortality during the study interval for open repair was 15% at LV hospitals vs 11% at HV hospitals (P < .01), whereas TEVAR mortality was similar, at 3.9% in LV vs 5.5% in HV hospitals (P = .43). LV was independently associated with increased mortality after open repair (odds ratio, 1.4; 95% confidence interval, 1.1-1.8; P < .01) but not after TEVAR. There was no independent effect of hospital teaching status on mortality or complications after open repair or TEVAR repair. CONCLUSIONS The total number of DTA repairs has significantly increased. Operative mortality for TEVAR is independent of hospital volume and type, whereas mortality after open surgery is lower at HV hospitals, suggesting that TEVAR can be safely performed across a spectrum of hospitals, whereas open surgery should be performed only at HV hospitals.

A risk prediction model for determining appropriateness of CEA in patients with asymptomatic carotid artery stenosis.

Objective: The benefit of carotid endarterectomy (CEA) over medical therapy in patients with asymptomatic carotid artery stenosis is predicated upon a life expectancy of at least 5 years after the procedure. The goal of this study was to create a scoring system for prediction of 5-year survival after CEA that can be used to triage patients with ACAS. Methods: All patients who underwent CEA for severe asymptomatic carotid stenosis from 1989 to 2005 were identified. Long-term survival was determined by a review of hospital records and the social security death index. Because all patients had at least 5-year follow-up, a logistic regression of predictors of survival at 5 years was performed and the odds ratios associated with particular significant comorbidities were used to create a scoring system to predict survival. The scoring system was then validated within the cohort using the Hosmer-Lemeshow Test and a derivation/validation receiver operating characteristic (ROC) curve. Results: There were 2004 CEA performed in 1791 patients. The average follow-up was 130 ± 49 months. The clinical profile of the cohort data included 84% hypertension, 56% coronary artery disease (CAD), 24% diabetes, and 71% on statins. The 30-day stroke rate was 1.1% and the death rate was 0.7%. The actual 5-year survival was 73%. Logistic regression yielded the following predictors of mortality: age (by decade) (odds ratio [OR] = 1.8, P < 0.0001), CAD (OR = 1.5, P = 0.0007), chronic obstructive pulmonary disease (OR = 2.5; P < 0.0001), diabetes (OR = 1.7, P < 0.0001), neck radiation (OR = 2.6, P = 0.005), no statin (OR = 2.1, P < 0.0001), and creatinine more than 1.5 (OR = 2.6, P < 0.0001). These variables were then assigned a hierarchal point scoring system in accordance with the OR value. The 5-year survival based on the scoring system was as follows: 0 to 5 points = 92.5%, 6 to 8 points = 83.6%, 9 to 11 points = 63.7%, 12 to 14 points = 46.5%, and more than 15 points = 33.8%. The Hosmer-Lemeshow test validated the scoring system (P = 0.26) and there was no difference in the ROC curves (C statistic = 0.74 vs 0.73). Conclusions: This validated scoring system can be a useful tool for determining which patients are likely to benefit most from CEA based on the probability of long-term survival. Given that the 5-year survival of patients in the medical arm of the asymptomatic CEA trials was 60% to 70%, it is reasonable to conclude that patients who score 0 to 8 points are excellent candidates for CEA whereas most patients with ≥12 points should be managed with medical therapy alone.

PS160. Applicability of the Society for Vascular Surgery's Objective Performance Goals for Critical Limb Ischemia to Current Practice of Lower Extremity Bypass

Background: In 2009, the Society for Vascular Surgery (SVS) established objective performance goals (OPGs) for critical limb ischemia (CLI) based on data from previous, randomized, controlled trials of lower-extremity bypass (LEB). These OPG sought to establish a benchmark of outcomes to which one could compare future endovascular therapy. However, the cohort used to develop the OPG excluded all patients who required prosthetic conduit and those with end-stage renal disease (ESRD), possibly limiting the generalizability of these results and the subsequent guidelines. The goal of this study was to determine if the SVS OPG are applicable to the current population of patients undergoing LEB. Methods: All patients who underwent infrainguinal LEB for CLI from January 2010 to December 2013 were identified in a prospectively maintained database. Patients were stratified into OPG eligible and ineligible (non-OPG) groups based on their demographic and operative characteristics. OPG eligible patients were further stratified into high risk and average risk. Outcomes included 30-day major adverse limb events (MALEs), 30-day major adverse cardiovascular events (MACE), 1-year survival, and 1-year freedom from amputation. Results: A total of 89 individual patients were identified. Only 43 (48%) patients met OPG inclusion criteria and 46 (52%) were not OPG eligible (non-OPG). The 30-day MALE was 8.7% (13.0% non-OPG vs. 7.0% OPG, P 1⁄4 0.34). The 30-day MACE was 11.2% (13.0% non-OPG vs. 9.3% OPG, P 1⁄4 0.58). One-year survival was 80.3% ± 4.5% (71.2% non-OPG vs. 90.0% OPG, P 1⁄4 0.21). One-year freedom from amputation was 71.7% ± 5.5% (58.8% non-OPG vs. 84.0% OPG, P 1⁄4 0.03). Conclusions: The SVS OPG for LEB are likely not generalizable to current practice as 51% of patients would have been excluded from the SVS cohort because of ESRD and prosthetic conduit. Most SVS OPG (30-day MALE, 1-year survival, and 1-year limb salvage) were attainable in patients who met SVS OPG inclusion criteria; but for the patients who are not OPG eligible, new benchmarks are needed.