Faculty Bibliography

When ruptured abdominal aortic aneurysms (AAAs) are not treated, they cause death. In addition, ruptured abdominal aortic aneurysms (RAAAs) have high mortality (35%-70%) and morbidity rates when treated by standard open surgical methods. These high perioperative mortality and morbidity rates have not been substantially reduced despite the introduction of many improvements in open operative technique or perioperative care. Endovascular approaches to treat AAAs introduced in the early 1990s provided an opportunity to substantially alter treatment outcomes when rupture occurred. This article details how these endovascular approaches, which include endovascular stented grafts, can be applied to the treatment of RAAAs, and what advantages these new catheter-based approaches to treatment offer

Obesity independently increases the risk of pulmonary embolism (PE). We compare a superobese population (body mass index [BMI] > 55 kg/m(2)) undergoing open gastric bypasses (OGBs) with a similarly matched group of laparoscopic gastric bypasses (LGB) to see if the incidence of PE differs. We included all patients undergoing OGB (n = 193, average BMI = 51 kg/m(2)) at our institution by a single surgeon between July 1999 and April 2001. Thirty-one patients were superobese (BMI > 55 kg/m(2)). LGB was started at our institution in April 2001. Since that time 213 patients (average BMI = 52 kg/m(2)) have undergone the procedure. One hundred and nine patients were superobese. Pre- and postoperative prophylaxis included sequential compression stockings and subcutaneous heparin. Postoperatively, patients who developed signs of hypoxia, tachypnea, or tachycardia underwent a chest X-ray and spiral computed tomography. In addition, all patients who expired in the 30-day postoperative period underwent postmortem examination. Data were analyzed using the chi-squared test. In the OGB group, four patients (2.1%) developed PE. All occurred in superobese patients with a BMI > 55 kg/m(2). Three were fatal PEs and one was nonfatal. None of these patients had a prior history of deep vein thrombosis, PE, venous stasis disease, or pulmonary hypertension. In the LGB group, one patient (0.9%) had a nonfatal PE. This patient had a history of deep vein thrombosis. The incidence of PE was statistically higher in the superobese OGB group (P < 0.01). Despite the theoretical hindrance to venous return and vena caval compression observed with pneumoperitoneum, fewer PEs occurred in the laparoscopic group. Our data, however, suggest that patients with a BMI > 55 kg/m(2) might be at an increased risk for PE independent of operative approach

Gender differences have been demonstrated in blood flow velocities by duplex ultrasonography (DU) in patients with carotid stenosis. Currently, DU is the most widely used method of follow-up monitoring after carotid angioplasty and stenting (CAS). To identify possible gender differences in carotid flow velocities, we analyzed our experience with DU obtained before and immediately after CAS. In a series of 47 CAS procedures over a 2.5-year period performed in 31 men and 15 women, carotid angiograms and duplex flow velocities were obtained preoperatively and within 24 hr after CAS. Carotid velocity profiles were compared with the angiographic degree of carotid stenosis. Gender differences in blood velocities were assessed using parametric and nonparametric statistical tests. Overall, women had median blood velocities 5-10% higher than men, although the differences were not statistically significant. DU obtained immediately after CAS revealed that median blood flow velocities were very similar among men and women (P > 0.4). In conclusion, although women have higher carotid blood flow velocities than men do, gender differences are notably absent on follow-up DU after carotid stenting. Our data indicate that similar criteria should be used after CAS for interpreting carotid velocity profiles in both women and men

BACKGROUND: A randomized clinical trial from the United Kingdom (EVAR trial 2) comparing endovascular aortic aneurysm repair (EVAR) with no intervention found no advantage for EVAR in patients with high risk. This finding was predominantly caused by the substantial in-hospital mortality after EVAR (9%). HYPOTHESIS: The nationwide in-hospital mortality for patients with the highest risk undergoing EVAR in the United States is lower than that reported in EVAR trial 2. DESIGN: Population-based, cross-sectional study. SETTING: The 2001-2004 Nationwide Inpatient Sample. PATIENTS AND METHODS: The Nationwide Inpatient Sample identified EVAR procedures for nonruptured abdominal aortic aneurysms. Risk stratification was based on comorbidities and the Charlson comorbidity index, a validated predictor of in-hospital mortality after abdominal aortic aneurysms repairs. Weighted univariate and logistic regression analyses were used to determine the association between comorbidity measures and risk-adjusted in-hospital mortality. RESULTS: During the 4-year period, 65 502 EVARs were performed with an in-hospital mortality of 2.2%. Risk-adjusted in-hospital mortality rates ranged from 1.2% to 3.7%. Stratified analyses, including only elective EVAR procedures, revealed that in-hospital mortality was significantly higher in patients with the most severe comorbidities (1.7%) vs those with lower comorbidity (0.4%; P<.001). Patients with high risk had only a 1.6-fold increased risk of adjusted in-hospital mortality (odds ratio, 1.6; 95% confidence interval, 1.2-2.2) compared with patients with low risk. CONCLUSIONS: The EVAR procedure is currently being performed in the United States with low in-hospital mortality, even in patients with the highest risk. Therefore, EVAR should not be denied to high-risk patients with abdominal aortic aneurysms in the United States on the basis of the level I evidence from the United Kingdom study

The intravascular and extravascular effects of percutaneous closure devices have not been well studied. We assessed the performance and healing characteristics in dogs of two devices approved by the US Food and Drug Administration. Nine adult male dogs were anesthesized prior to percutaneous access of both femoral arteries with a 6F sheath. All dogs were systemically heparinized to an activated clotting time (ACT) > 250 seconds. Duplex sonography was performed preoperatively to measure vessel diameter and flow velocity. In each dog, one of two devices (Perclose, Abbot Laboratories, Abbott Park, IL or Angio-Seal, St. Jude Medical, St. Paul, MN) was randomly deployed into one of the two femoral arteries. The other device was deployed on the opposite side. Duplex sonography was repeated immediately after deployment and 28 days later to measure changes in vessel diameter and flow velocity. At 28 days, angiography was performed on both femoral arteries before they were removed for histologic evaluation. The time required to excise each vessel reflected the degree of scarring. Hemostasis time for the Angio-Seal device far surpassed the Perclose device (39 +/- 7 vs 0 minutes; p < .05). Vessel narrowing was observed only at 28 days after deployment of the Angio-Seal device (p < .05). Extensive extravascular scarring was observed with the Angio-Seal device, which resulted in a longer femoral artery dissection time and greater periadventitial scar thickness compared with the Perclose device (p < .05). When compared with the Perclose suture closure device, the Angio-Seal collagen plug closure device prolonged hemostasis time and produced greater vessel narrowing and periadventitial inflammation (extravascular scarring) in a canine model at 4 weeks