Ruptured Abdominal Aortic Aneurysm: Endovascular Repair Does Not Confer Any Long-term Survival Advantage Over Open Repair

The Adoption of Surgical Innovations at Academic Versus Nonacademic Health Centers

PURPOSE

The value of the health care services provided by academic health centers (AHCs) in the United States increasingly is being questioned. AHCs play a prominent role in developing new surgical innovations, including new minimally invasive techniques, which are costly up front but can lead to significant benefits like decreased morbidity and lengths of stays. This study explored the role of AHCs in the adoption of these surgical innovations as a novel measure of their value.

METHOD

The authors combined data from the American Hospital Association and the State Inpatient Databases from California, Florida, Washington State, and New York. They compared the number and percentage of patients who received four new, innovative surgical procedures (vs. those who received the traditional procedures) at Council of Teaching Hospitals (COTH) hospitals to those at non-COTH hospitals from 2009 to 2011.

RESULTS

Overall, 61.1% (27,175) of the procedures performed at COTH hospitals used new techniques, compared with 47.2% (41,680) at non-COTH hospitals, across all years (P < .0001). The number and percentage of procedures using the new techniques increased in all years and for all procedures.

CONCLUSIONS

Not only do AHCs play a role in developing surgical innovations but they also adopt these new techniques more quickly than other hospitals, and thereby they provide additional benefits to patients. These findings provide an important and understudied perspective on the value of AHCs.

Ruptured Abdominal Aortic Aneurysm: Prediction of Mortality From Clinical Presentation and Glasgow Aneurysm Score

OBJECTIVE

To examine association of presenting clinical acuity and Glasgow Aneurysm Score (GAS) with perioperative and 1-year mortality.

DESIGN

Retrospective chart review.

SETTING

Major tertiary care facility.

PARTICIPANTS

Patients with ruptured abdominal aortic aneurysm (rAAA) from 2003 through 2013.

INTERVENTIONS

Emergency repair of rAAA.

MEASUREMENTS AND MAIN RESULTS

The authors reviewed outcomes after stable versus unstable presentation and by GAS. Unstable presentation included hypotension, cardiac arrest, loss of consciousness, and preoperative tracheal intubation. In total, 125 patients (40 stable) underwent repair. Perioperative mortality rates were 41% and 12% in unstable and stable patients, respectively (p<0.001). Unstable status had 88% sensitivity and 41% specificity for predicting perioperative mortality. Using logistic regression, higher GAS was associated with perioperative mortality (p<0.001). Using receiver operating characteristic analysis, the area under the curve was 0.72 (95% CI, 0.62-0.82) and cutoff GAS≥96 had 63% and 72% sensitivity and specificity, respectively. Perioperative mortality for GAS≥96 was 51% (25/49), whereas it was 20% (15/76) for GAS≤95. The estimated 1-year survival (95% CI) was 75% (62%-91%) for stable patients and 48% (38%-60%) for unstable patients. Estimated 1-year survival (95% CI) was 23% (13%-40%) for GAS≥96 and 77% (67%-87%) for GAS≤95.

CONCLUSIONS

Clinical presentation and GAS identified patients with rAAA who were likely to have a poor surgical outcome. GAS≥96 was associated with poor long-term survival, but>20% of these patients survived 1 year. Thus, neither clinical presentation nor GAS provided reliable guidance for decisions regarding futility of surgery.

Tissue responses to endovascular stent grafts for saccular abdominal aortic aneurysms in a canine model

We investigated tissue responses to endoskeleton stent grafts for saccular abdominal aortic aneurysms (AAAs) in canines. Saccular AAAs were made with Dacron patch in 8 dogs, and were excluded by endoskeleton stent grafts composed of nitinol stent and expanded polytetrafluoroethylene graft. Animals were sacrificed at 2 months (Group 1; n = 3) or 6 months (Group 2; n = 5) after the placement, respectively. The aortas embedding stent grafts were excised en bloc for gross inspection and sliced at 5 to 8 mm intervals for histopathologic evaluation. Stent grafts were patent in all except a dog showing a thrombotic occlusion in Group 2. In the 7 dogs with patent lumen, the graft overhanging the saccular aneurysm was covered by thick or thin thrombi with no endothelial layer, and the graft over the aortic wall was completely covered by neointima with an endothelial layer. Transgraft cell migration was less active at an aneurysm than at adjacent normal aorta. In conclusion, endoskeleton stent grafts over saccular aneurysms show no endothelial coverage and poor transgraft cell migration in a canine model.

Endovascular repair of ruptured abdominal aortic aneurysm does not confer survival benefits over open repair

OBJECTIVE

Endovascular repair of ruptured abdominal aortic aneurysm (rAAA) is being increasingly performed despite lack of good evidence for its superiority. Other reported studies suffer from patient selection and publication bias with limited follow-up. This study is a single-center propensity score comparing early and midterm outcomes between open surgical repair (OSR) and endovascular repair of rAAA (REVAR).

METHODS

A retrospective review from January 2001 to November 2010 identified 312 patients who underwent rAAA repairs. Thirty-one patients with antecedent AAA repair and three with incomplete records were excluded, leaving 37 REVARs and 241 OSRs. Propensity score-based matching for sex, age, preoperative hemodynamic status, surgeon's annual AAA volume, and preoperative cardiopulmonary resuscitation was performed in a 1:3 ratio to compare outcomes. Thirty-seven REVARs were matched with 111 OSRs. Late survival was estimated by Kaplan-Meier methods.

RESULTS

Operative time and blood replacement were higher with OSR. Overall complication rates were similar (54% REVAR vs 66% OSR; P = .23), except for higher incidences of tracheostomies (21% vs 3%; P = .015), myocardial infarction (38% vs 18%; P = .036), and acute tubular necrosis (47% vs 21%; P = .009) with OSR. Operative mortality rates were similar (22% REVAR vs 32% OSR), with an odds ratio of 0.63 for REVAR (95% confidence interval = [0.24, 1.48]; P = .40). No differences in the incidences for secondary interventions for aneurysm- or graft-related complications were noted (22% REVAR vs 22% OSR; P = .99). Kaplan-Meier estimates of 1-, 2-, and 3-year survival rates were also similar (50%, 50%, 42% REVAR vs 54%, 52%, 47% OSR; P = .66).

CONCLUSIONS

REVAR for rAAA does not seem to conclusively confer either acute or late survival advantages. Routine use of REVAR should be deferred until prospective, randomized trial data become available.

Open surgery in endovascular aneurysm repair era: simplified classification in two risk groups owing to factors affecting mortality in 137 ruptured abdominal aortic aneurysms (RAAAs)

Our objective is to identify in 137 true RAAAs operated consecutively in open surgery: (1) diagnostic therapeutic aspects capable of influencing results, (2) risk classes with different prognosis, (3) any situations where the prognosis is so negative that surgery is not recommended. The relationship of 16 anamnestic, clinical and technical parameters prospectively collected with 30-day mortality was retrospectively evaluated by uni- and multivariate analyses. Thirty-day mortality was 37%. The univariate analysis identified as mortality predictors Hb ≤ 8 g/dl and circulatory shock at hospitalisation, but following the multivariate analysis only circulatory shock was a certainly significant risk-factor. The cumulative effect on mortality of the two parameters identified at univariate analysis translates into a statistically significant difference in mortality between two groups of patients: A (no or just one risk-factor) and B (two risk-factors). To reinstate euvolemia, rather than adequate haemoglobin values, improves the chances of success. A simple prognostic index into two risk classes is feasible, but abstention from surgery is not justified in any type of patient.

The management of abdominal aortic aneurysms

Abdominal aortic aneurysms cause about 6000 deaths per year in England and Wales, predominantly from rupture. Significant progress has been made in recent years in developing minimally invasive, endovascular methods of treatment. This review evaluates the current management options for abdominal aortic aneurysm.

Open repair for ruptured abdominal aortic aneurysm: is it possible to predict survival?

The aim of the study was to determine variables that could be used to predict survival in patients with ruptured abdominal aortic aneurysm (RAAA) and to assess the accuracy of the Glasgow Aneurysm Score (GAS) and the Acute Physiology Chronic Health Evaluation II (APACHE-II). From January 1998 to July 2006, 103 patients underwent operations for RAAA. For each patient, 44 variables were retrospectively recorded in a database. Data were analyzed with univariate and multivariate methods. In the univariate analysis significant predictors of death were hypotension (p=0.001), preexisting peripheral vascular disease (p<0.001), renal insufficiency (p=0.037), chronic obstructive pulmonary disease (p=0.028), level of HCO(3)(-) (p<0.001), intraperitoneal rupture (p=0.001), blood transfused (p<0.001), cardiac complications (p<0.001), and APACHE-II score (p=0.001). Multivariate analysis confirmed statistical significance for coexisting peripheral vascular disease (p<0.001), diastolic blood pressure at admission <60 mm Hg (p=0.039), APACHE-II score >18.5 (p=0.025), HCO(3)(-) <21 mg/dL (p<0.001), and intraperitoneal rupture of the aneurysm (p=0.011) as predictors of death. Results of the study suggested that different factors can be helpful in identifying those patients whose operative risk is prohibitive. APACHE-II, contrary to GAS, is an accurate system to predict postoperative death after repair for RAAA.