Rodney P. Bensley

Changes in abdominal aortic aneurysm rupture and short-term mortality, 1995-2008: a retrospective observational study.

Objective:To examine the modern epidemiology of abdominal aortic aneurysm (AAA) rupture and short-term AAA-related mortality after the introduction of endovascular aneurysm repair (EVAR). Background:Previous epidemiologic studies have demonstrated stable rates of AAA repair, repair mortality, and AAA rupture. Recently, EVAR has been introduced as a less invasive treatment method, and its use has expanded to more than 75% of elective AAA repairs. Methods:We identified Medicare beneficiaries undergoing AAA repair and those hospitalized with a ruptured AAA during the period 1995 to 2008 and calculated standardized annual rates of AAA-related deaths due to either elective repair or rupture. Results:A total of 338,278 patients underwent intact AAA repair during the study period. There were 69,653 patients with AAA rupture, of whom 47,524 underwent repair. Intact repair rates increased substantially in those older than 80 years (57.7–92.3 per 100,000, P < 0.001) but decreased in those 65 to 74 years old (81.8–68.9, P < 0.001). A decline in ruptures with and without repair was seen in all age groups. By 2008, 77% of all intact repairs and 31% of all rupture repairs were performed with EVAR (P < 0.001). Operative mortality declined during the study period for both intact (4.9%–2.4%, P < 0.001) and ruptured (44.1%–36.3%, P < 0.001) AAA repair. Short-term AAA-related deaths decreased by more than half (26.1–12.1 per 100,000, P < 0.001), with the greatest decline occurring in those older than 80 years (53.7–27.3, P < 0.001). Conclusions:A recent decline in AAA rupture and short-term AAA-related mortality is demonstrated and likely related in part to the introduction and expansion of EVAR. This is due to decreased deaths from ruptures (with and without repair) and decreased mortality with intact repairs, particularly in patients older than 80 years.

Gender differences in abdominal aortic aneurysm presentation, repair, and mortality in the Vascular Study Group of New England

OBJECTIVE Prior studies of gender differences in abdominal aortic aneurysm (AAA) repair suggest there may be differences in presentation, suitability for endovascular aneurysm repair (EVAR), and outcomes between men and women. METHODS We used the Vascular Study Group of New England database to identify all patients undergoing EVAR or open AAA repair. We analyzed demographics, comorbidities, and procedural, and perioperative data. Results were compared using the Fisher exact test and the Student t-test. Multivariable logistic regression and Cox proportional hazards modeling were performed to identify predictors of mortality. RESULTS We identified 4026 patients (78% men) who underwent AAA repair (54% EVAR). Women were less likely than men to undergo EVAR for intact aneurysms (50% vs 60% of intact AAA repair; P < .001) but not for ruptured aneurysms (26% vs 20%; P = .23). Women were older (median age, 75 vs 72 years for intact; P < .001; 78 vs 73 years for rupture; P < .001) with smaller aortic diameters (57 vs 59 mm for elective; P < .001; 71 vs 79 mm for rupture; P < .001). Arterial injury was more common in women (5.4% vs 2.7%; P = .013) among patients undergoing EVAR for intact aneurysms. Women stayed in the hospital longer (4.3 vs 2.7 days; P = .018) and had lower odds of being discharged home, even after adjusting for age. Among patients undergoing open repair for intact aneurysms, women more frequently experienced leg ischemia/emboli (4% vs 1%; P = .001) and bowel ischemia (5% vs 3%; P = .044). Women had higher 30-day mortality after OAR for intact (4% vs 2%; P = .03) and rupture (48% vs 34%; P = .03) repairs. However, 30-day mortality after EVAR was similar for intact (1% in men vs 1% in women; P = .57) and rupture (29% in men vs 27% in women; P > .99) repairs. Late survival was worse in women than men only for patients undergoing open repair of ruptured aneurysms (hazard ratio, 1.8; 95% confidence interval, 1.0-3.1; P = .04). After controlling for age, type of repair, urgency at presentation (ie, elective/intact vs ruptured), comorbidities, and other relevant risk factors, gender was not predictive of 30-day or 1-year mortality. CONCLUSIONS Women with AAAs are being treated at older ages and smaller AAA diameters and are undergoing rupture repair at smaller diameters than men. Women are more likely to experience perioperative complications as a result of less favorable vascular anatomy. Age >80 years, comorbidity, presentation, and type of repair are more important predictors of mortality than gender.

Comparative effectiveness of endovascular versus open repair of ruptured abdominal aortic aneurysm in the Medicare population

OBJECTIVE Endovascular aortic repair (EVAR) for abdominal aortic aneurysm (AAA) is increasingly used for emergent treatment of ruptured AAA (rAAA). We sought to compare the perioperative and long-term mortality, procedure-related complications, and rates of reintervention of EVAR vs open aortic repair of rAAA in Medicare beneficiaries. METHODS We examined perioperative and long-term mortality and complications after EVAR or open aortic repair performed for rAAA in all traditional Medicare beneficiaries discharged from a United States hospital from 2001 to 2008. Patients were matched by propensity score on baseline demographics, coexisting conditions, admission source, and hospital volume of rAAA repair. Sensitivity analyses were performed to evaluate the effect of bias that might have resulted from unmeasured confounders. RESULTS Of 10,998 patients with repaired rAAA, 1126 underwent EVAR and 9872 underwent open repair. Propensity score matching yielded 1099 patient pairs. The average age was 78 years, and 72.4% were male. Perioperative mortality was 33.8% for EVAR and 47.7% for open repair (P < .001), and this difference persisted for >4 years. At 36 months, EVAR patients had higher rates of AAA-related reinterventions than open repair patients (endovascular reintervention, 10.9% vs 1.5%; P < .001), whereas open patients had more laparotomy-related complications (incisional hernia repair, 1.8% vs 6.2%; P < .001; all surgical complications, 4.4% vs 9.1%; P < .001). Use of EVAR for rAAA increased from 6% of cases in 2001 to 31% in 2008, whereas during the same interval, overall 30-day mortality for admission for rAAA, regardless of treatment, decreased from 55.8% to 50.9%. CONCLUSIONS EVAR for rAAA is associated with lower perioperative and long-term mortality in Medicare beneficiaries. Increasing adoption of EVAR for rAAA is associated with an overall decrease in mortality of patients hospitalized for rAAA during the last decade.

Presentation, treatment, and outcome differences between men and women undergoing revascularization or amputation for lower extremity peripheral arterial disease

OBJECTIVE Prior studies have suggested treatment and outcome disparities between men and women for lower extremity peripheral arterial disease after surgical bypass. Given the recent shift toward endovascular therapy, which has increasingly been used to treat claudication, we sought to analyze sex disparities in presentation, revascularization, amputation, and inpatient mortality. METHODS We identified individuals with intermittent claudication and critical limb ischemia (CLI) using International Classification of Diseases, Ninth Revision codes in the Nationwide Inpatient Sample from 1998 to 2009. We compared presentation at time of intervention (intermittent claudication vs CLI), procedure (open surgery vs percutaneous transluminal angioplasty or stenting vs major amputation), and in-hospital mortality for men and women. Regional and ambulatory trends were evaluated by performing a separate analysis of the State Inpatient and Ambulatory Surgery Databases from four geographically diverse states: California, Florida, Maryland, and New Jersey. RESULTS From the Nationwide Inpatient Sample, we identified 1,797,885 patients (56% male) with intermittent claudication (26%) and CLI (74%), who underwent 1,865,999 procedures (41% open surgery, 20% percutaneous transluminal angioplasty or stenting, and 24% amputation). Women were older at the time of intervention by 3.5 years on average and more likely to present with CLI (75.9% vs 72.3%; odds ratio [OR], 1.21; 95% confidence interval [CI], 1.21-1.23; P < .01). Women were more likely to undergo endovascular procedures for both intermittent claudication (47% vs 41%; OR, 1.27; 95% CI, 1.25-1.28; P < .01) and CLI (21% vs 19%; OR, 1.14; 95% CI, 1.13-1.15; P < .01). From 1998 to 2009, major amputations declined from 18 to 11 per 100,000 in men and 16 to 7 per 100,000 in women, predating an increase in total CLI revascularization procedures that was seen starting in 2005 for both men and women. In-hospital mortality was higher in women regardless of disease severity or procedure performed even after adjusting for age and baseline comorbidities (.5% vs .2% after percutaneous transluminal angioplasty or stenting for intermittent claudication; 1.0% vs .7% after open surgery for intermittent claudication; 2.3% vs 1.6% after percutaneous transluminal angioplasty or stenting for CLI; 2.7% vs 2.2% after open surgery for CLI; P < .01 for all comparisons). CONCLUSIONS There appears to be a preference to perform endovascular over surgical revascularization among women, who are older and have more advanced disease at presentation. Percutaneous transluminal angioplasty or stenting continues to be popular and is increasingly being performed in the outpatient setting. Amputation and in-hospital mortality rates have been declining, and women now have lower amputation but higher mortality rates than men. Recent improvements in outcomes are likely the result of a combination of improved medical management and risk factor reduction.

Accuracy of administrative data versus clinical data to evaluate carotid endarterectomy and carotid stenting.

OBJECTIVE Administrative data have been used to compare carotid endarterectomy (CEA) and carotid artery stenting (CAS). However, there are limitations in defining symptom status, Centers for Medicare and Medicaid Services high-risk status, as well as complications. Therefore, we did a direct comparison between administrative data and physician chart review as well as between data collected for the National Surgical Quality Improvement Program (NSQIP) and physician chart review for CEA and CAS. METHODS We performed an outcomes analysis on all CEA and CAS procedures from 2005 to 2011. We obtained International Classification of Diseases, Ninth Revision diagnosis codes from hospital discharge records regarding symptom status, high-risk status, and perioperative stroke. We also obtained data on all CEA patients submitted to NSQIP over the same time period. One of the study authors (R.B.) then performed a chart review of the same patients to determine symptom status, high-risk status, and perioperative strokes and the results were compared. RESULTS We identified 1342 patients who underwent CEA or CAS between 2005 and 2011 and 392 patients who underwent CEA that were submitted to NSQIP. Administrative data identified fewer symptomatic patients (17.0% vs 34.0%), physiologic high-risk patients (9.3% vs 23.0%), and anatomic high-risk patients (0% vs 15.2%). Although administrative data identified a similar proportion of perioperative strokes (1.9% vs 2.0%), this was due to the fact that these data identified eight false positive and nine false negative perioperative strokes. NSQIP data identified more symptomatic patients compared with chart review (44.1% vs 30.3%), fewer physiologic high-risk patients (13.0% vs 18.6%), fewer anatomic high-risk patients (0% vs 6.6%), and a similar proportion of perioperative strokes (1.5% vs 1.8%, only one false negative stroke and no false positives). CONCLUSIONS Administrative data are unreliable for determining symptom status, high-risk status, and perioperative stroke and should not be used to analyze CEA and CAS. NSQIP data do not adequately identify high-risk patients, but do accurately identify perioperative strokes and to a lesser degree, symptom status.

Ultrasound-guided percutaneous endovascular aneurysm repair success is predicted by access vessel diameter

OBJECTIVE Ultrasound scan-guided access allows for direct visualization of the access artery during percutaneous endovascular aortic aneurysm repair. We hypothesized that the use of ultrasound scan guidance allowed us to safely increase the utilization of percutaneous endovascular aortic aneurysm repair to almost all patients and decrease access complications. METHODS A retrospective chart review of all elective endovascular aortic aneurysm repairs, both abdominal and descending thoracic, from 2005 to 2010 was performed. Patients were identified using International Classification of Disease, 9th Revision, Clinical Modification Codes and stratified based on access type: percutaneous vs cut-down. We examined the success rate of percutaneous access and the cause of failure. Sheath size was large (18-24 F) or small (12-16 F). Minimum access vessel diameter was also measured. Outcomes were wound complications (infections or clinically significant hematomas that delayed discharge or required transfusion), operative and incision time, length of stay, and discharge disposition. Predictors of percutaneous failure were identified. RESULTS One hundred sixty-eight patients (296 arteries) had percutaneous access endovascular aneurysm repair (P-EVAR) whereas 131 patients (226 arteries) had femoral cutdown access EVAR. Ultrasound scan-guided access was introduced in 2007. P-EVAR increased from zero cases in 2005 to 92.3% of all elective cases in 2010. The success rate with percutaneous access was 96%. Failures requiring open surgical repair of the artery included seven for hemorrhage and six for flow-limiting stenosis or occlusion of the femoral artery. P-EVAR had fewer wound complications (0.7% vs 7.4%; P = .001), shorter operative time (153.3 vs 201.5 minutes; P < .001), and larger minimal access vessel diameter (6.7 mm vs 6.1 mm; P < .01). Patients with failed percutaneous access had smaller minimal access vessel diameters when compared to successful P-EVAR (4.9 mm vs 6.8 mm; P < .001). More failures occurred in small sheaths than large ones (7.4% vs 1.9%; P = .02). Access vessel diameter <5 mm is predictive of percutaneous failure (16.7% of vessels <5 mm failed vs 2.4% of vessels ≥ 5 mm failed; P < .001; odds ratio, 7.3; 95% confidence interval, 1.58-33.8; P = .01). CONCLUSIONS Ultrasound scan-guided P-EVAR can be performed in the vast majority of patients with a high success rate, shorter operative times, and fewer wound complications. Access vessel diameters <5 mm are at greater risk for percutaneous failure and should be treated selectively.

Defining Perioperative Mortality after Open and Endovascular Aortic Aneurysm Repair in the US Medicare Population

BACKGROUND Perioperative mortality is reported after abdominal aortic aneurysm (AAA) repair, but there is no agreed upon standard definition. Often, 30-day mortality is reported because in-hospital mortality may be biased in favor of endovascular repair given the shorter length of stay. However, the duration of increased risk of death after aneurysm repair is unknown. STUDY DESIGN We used propensity score modeling to create matched cohorts of US Medicare beneficiaries undergoing endovascular (n = 22,830) and open (n = 22,830) AAA repair from 2001 to 2004. We calculated perioperative mortality using several definitions including in-hospital, 30-day, and combined 30-day and in-hospital mortality. We determined the relative risk (RR) of death after open compared with endovascular repair as well as the absolute mortality difference. To define the duration of increased risk we calculated biweekly interval death rates for 12 months. RESULTS In-hospital, 30-day, and combined 30-day and in-hospital mortality for open and endovascular repair were 4.6% versus 1.1%, 4.8% versus 1.6%, and 5.3% versus 1.7%, respectively. The absolute differences in mortality were similar, at 3.5%, 3.2%, and 3.7%. The RRs of death (95% confidence interval) were 4.2 (3.6 to 4.8), 3.1 (2.7 to 3.4), and 3.2 (2.8 to 3.5). Biweekly interval death rates were highest during the first month after endovascular repair (0.6%) and during the first 2.5 months (0.5% to 2.1%) after open repair. After 2.5 months, rates were similar for both repairs (<0.5%) and stabilized after 3 months. The 90-day mortality rates for open and endovascular repair were 7.0% and 3.2%, respectively. CONCLUSIONS In-hospital mortality comparisons overestimate the benefit of endovascular repair compared with 30-day or combined 30-day and in-hospital mortality. The total mortality impact of AAA repair is not realized until 3 months after repair and the duration of highest mortality risk extends longer for open repair.

Open repair of intact thoracoabdominal aortic aneurysms in the American College of Surgeons National Surgical Quality Improvement Program

OBJECTIVE Open surgical repair of thoracoabdominal aortic aneurysms (TAAAs) is uncommon. Mortality rates of 20% are reported in studies using national data and are 5% to 8% in single-institution studies. Clinical trials are currently evaluating branched and fenestrated endografts. The purpose of this study is to establish a benchmark for future comparisons with endovascular trials using open repair of TAAAs in the National Surgical Quality Improvement Program (NSQIP) database. METHODS We identified all patients undergoing open elective and emergency surgical repair of intact TAAAs in NSQIP (2005 to 2010) using Current Procedural Terminology (American Medical Association, Chicago, Ill) and International Classification of Diseases, 9th Edition codes. We analyzed demographics, comorbidities, 30-day mortality, postoperative complications, and length of stay. Multivariable logistic regression was used to identify predictors of mortality. RESULTS We identified 450 patients who underwent open surgical repair (418 elective, 32 emergent) of an intact TAAA. Mean age was 69.4 years, 60.7% were male, and 85.6% were white. Comorbidities included hypertension (87.1%), chronic obstructive pulmonary disease (27.3%), prior stroke or transient ischemic attack (16.7%), diabetes (11.6%), and peripheral vascular disease (9.6%). Thirty-day mortality was 10.0%. Pulmonary complications were the most common: failure to wean from ventilator (39.1%), pneumonia (23.1%), and reintubation (13.8%). Acute renal failure requiring dialysis occurred in 10.7% of patients. Multivariable analysis (odds ratio [95% confidence interval]) showed predictors of mortality were emergent repair (3.3 [1.03-10.83]; P = .04), age >70 years (3.5 [1.03-7.56], P = .001), preoperative dialysis (8.4 [1.90-37.29], P = .005), cardiac complication (2.9 [1.05-8.21], P = .04), and renal complications (8.4 [3.41-20.56], P < .001). CONCLUSIONS In this study of NSQIP hospitals, the first to analyze open surgical repair of TAAAs, the 30-day mortality rate of 10.0% is similar to single-institution reports. However, morbidity and mortality after open TAAA repair remain high, confirming the need for less invasive procedures.

Risk of Late-Onset Adhesions and Incisional Hernia Repairs after Surgery

BACKGROUND Long-term adhesion-related complications and incisional hernias after abdominal surgery are common and costly. There are few data on the risk of these complications after different abdominal operations. STUDY DESIGN We identified Medicare beneficiaries who underwent endovascular repair of an abdominal aortic aneurysm from 2001-2008 who presumably are not at risk for laparotomy-related complications. We identified all laparoscopic and open operations involving the abdomen, pelvis, or retroperitoneum and categorized them into 5 groups according to invasiveness. We then identified laparotomy-related complications for up to 5 years after the index operation and compared these with the baseline rate of complications in a control group of patients who did not undergo an abdominal operation. RESULTS We studied 85,663 patients, 7,513 (8.8%) of which underwent a laparotomy, including 2,783 major abdominal operations, 709 minor abdominal operations, 963 ventral hernia repairs, 493 retroperitoneal/pelvic operations, and 2,565 laparoscopic operations. Mean age was 76.7 years and 82.0% were male. Major abdominal operations carried the highest risk for adhesion-related complications (14.3% and 25.0% at 2 and 5 years compared with 4.0% and 7.8% for the control group; p < 0.001) and incisional hernias (7.8% and 12.0% compared with 0.6% and 1.2% for the control group; p < 0.001). Laparoscopic operations (4.6% and 10.7% for adhesions, 1.9% and 3.2% for incisional hernias) carried the lowest risk. CONCLUSIONS Late-onset laparotomy-related complications are frequent and their risk extends through 5 years beyond the perioperative period. With the advancement and expansion of laparoscopic techniques and its attendant lower risk for long-term complications, these results can alter the risk-to-benefit profile of various types of abdominal operations and can also strengthen the rationale for additional development of laparoscopic approaches to abdominal operations.

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.