Ruptured Mycotic Abdominal Aortic Pseudoaneurysm in a Patient on Hemodialysis Complicated with Oxacillin-Resistant Staphylococcus aureus Bacteremia.

Despite a high incidence of Staphylococcus aureus bacteremia in hemodialysis patients, bacterial invasion with aortic wall infection resulting in a pseudoaneurysm rarely occurs. This report describes a case of mycotic pseudoaneurysm of the abdominal aorta that grew rapidly and ruptured into the distal vena cava causing persistent bacteremia in a patient undergoing hemodialysis complicated with oxacillin-resistant S. aureus bacteremia.

Avoiding the use of a femoral bridging catheter using a two-stage Hemodialysis Reliable Outflow (HeRO) graft implantation technique.

PURPOSE: To evaluate a two-stage Hemodialysis Reliable Outflow (HeRO) implantation technique that avoids the use of a femoral bridging catheter versus the conventional one-stage technique requiring a bridging catheter in selected patients. METHODS: A retrospective review was performed on 20 end-stage renal disease patients with an internal jugular vein (IJV) catheter selected for two-stage HeRO implantation at our institution between January 2010 and March 2013. The arterial graft component (AGC) was implanted without anastomosing it to the target artery (first stage). After AGC incorporation, the venous outflow component was inserted (second stage). The preexisting IJV catheter was maintained for hemodialysis access during the interstage period. Patient characteristics, patency using Kaplan-Meier method and infection rates were analyzed. RESULTS: A total of 17 patients with a mean age of 59 years (70.6% women) completed the two-stage procedure. During the interstage period (mean 12 weeks, range 4-22 weeks), no graft- or surgery-related infection occurred. The need of a femoral bridging catheter was avoided by utilizing the preexisting IJV dialysis catheter. The accumulated HeRO days were 3,916 days with a mean follow-up of 7.7 months (range 1-22.6 months). The HeRO-related infection rate was 0.3/1,000 days. The primary assisted and secondary patency rates at 6 months were 69% and 82%, respectively, which were similar to those of arteriovenous grafts. Staging conferred immediate vascular accessibility. CONCLUSIONS: Avoiding the use of a femoral bridging catheter using the two-stage technique may lower infection rate, with comparable primary assisted and secondary patency to arteriovenous grafts and added benefit of immediate cannulatability in this subset of patients.

Two-stage Hemodialysis Reliable Outflow (HeRO) graft implantation technique that avoids the use of a femoral bridging dialysis catheter.

PURPOSE: The purpose of this study is to report a novel two-stage Hemodialysis Reliable Outflow (HeRO) graft implantation technique that avoids the use of a femoral bridging hemodialysis catheter in internal jugular vein (IJV) catheter-dependent patients with contralateral central venous occlusion. METHODS: The first stage is to implant the ePTFE component and consists of: 1) performing two to three incisions in the upper arm ipsilateral to the preexisting IJV catheter, 2) tunneling the expanded polytetrafluoroethylene (ePTFE) component through these incision sites, and 3) placing the ePTFE component in the subcutaneous tissue without anastomosing it to the target artery. The preexisting IJV catheter is maintained to provide continuous dialysis access. The second stage is initiated in 4 weeks and includes: 1) thrombectomy and anastomosing the ePTFE component arterial end to the target artery, 2) insertion of the venous outflow component using the preexisting IJV catheter access site, and 3) connecting the venous outflow component to the ePTFE component in the standard fashion. RESULTS: The HeRO graft was successfully implanted in two stages without using a femoral bridging catheter. Immediate postimplant cannulatabilty was achieved upon completion of the second stage procedure. CONCLUSION: This novel two-stage HeRO implantation technique is simple, yet allows immediate cannulation upon completion of the second stage procedure while avoiding the need of a femoral bridging catheter in IJV catheter- dependent patients with contralateral central venous occlusion, and thus lowering the risk of infection related to a femoral bridging catheter.

Diagnosis and management of aneurysms involving the superior mesenteric artery and its branches--a report of four cases.

Aneurysms of the superior mesenteric artery (SMA) are an uncommon but lethal entity, which must be treated expeditiously to avoid mortality and high incidence of ischemic small bowel complications. In the past 7 years the authors have treated 4 patients with a variety of types of aneurysms involving the SMA and its branches at a university-based teaching hospital. The first was a mycotic SMA aneurysm as a result of septic mitral valve, the second a jejunal aneurysm in a patient with pancreatitis, the third a spontaneous dissection distal to a small SMA aneurysm with thrombus partially occluding the distal vessel, and the fourth an SMA aneurysm associated with the diagnosis of mesenteric insufficiency. All patients presented with abdominal pain. The diagnosis was made initially in 1 patient on plain abdominal films with a calcified aneurysm, on duplex scan in the second, and on computed tomography (CT) scans in the remaining 2. Treatment consisted of bowel resection and ligation of mycotic aneurysm in the first patient, of catheter embolization of jejunal aneurysm in the patient with pancreatitis, and of vein graft bypass in the patient with a large SMA aneurysm. The patient with SMA aneurysm and distal dissection with partially occluding thrombus received anticoagulation and is being followed up with serial CT scans. There were no deaths. One patient required bowel resection, which did not result in short gut syndrome. Improved abdominal duplex scanning and CT technology facilitates the diagnosis of mesenteric aneurysm. The broad spectrum of etiologies mandates that treatment be tailored to the individual patient, and it varies from endovascular techniques to traditional bypass surgery. Prompt diagnosis and treatment results in the lowest mortality rate and minimizes the prevalence of intestinal infarction.

The evaluation of morbidity and mortality in abdominal aortic aneurysm repair patients as related to body mass index.

BACKGROUND: This study evaluates the relationship between body mass index (BMI) and other comorbidities on the overall morbidity and mortality of abdominal aortic aneurysm (AAA) repair. METHODS: A database of all nonemergent open and endovascular AAA repairs performed at our center from 2004 to 2008 was created. The outcomes at the predefined time intervals were then evaluated for each group of patients. RESULTS: One hundred forty-three patients qualified for this study with a 3:2 stent graft-to-open ratio. A trend relating patient BMI with early mortality was noted. Age>80 years was a strong predictor of mortality in all time intervals. CONCLUSIONS: The outcomes for this population show a significant trend toward early mortality in open AAA repair patients with an elevated preoperative BMI. Appropriate patient selection and preoperative optimization are recommended for all AAA repair candidates; however, some innate characteristics such as patient age, may play the largest role in determining outcomes.

Aortic mural thrombus embolization: an unusual presentation of essential thrombocytosis.

Hypercoagulable conditions are increasingly recognized as a causative factor in patients with thromboembolic phenomenon. Essential thrombocytosis (ET) is one such condition. This particular myeloproliferative disorder is most commonly associated with thrombotic complications of the microvasculature and bleeding complications involving mucosal surfaces (e.g., gastrointestinal tract bleeding). This case identifies an uncommon manifestation of ET-aortic mural thrombus leading to visceral embolism. Vascular surgeons should be aware of the diagnosis, treatment, and complications of ET, as patients with this condition may first present with an arterial occlusion.

Response of plasma matrix metalloproteinase-9 to conventional abdominal aortic aneurysm repair or endovascular exclusion: implications for endoleak.

PURPOSE: Matrix metalloproteinases are enzymes capable of breaking down all of the components of the extracellular matrix and have been implicated in the development of aneurysm formation. Because matrix metalloproteinase-9 (MMP-9) levels are elevated in aortic aneurysmal tissue and in that patient plasma, we hypothesized that plasma MMP-9 levels should decrease significantly after conventional and endovascular infrarenal abdominal aortic aneurysm (AAA) repair but that plasma MMP-9 levels would remain elevated in patients with endoleaks. METHODS: A sandwich enzyme-linked immunosorbent assay was used to measure plasma levels of MMP-9 in patients with AAA who underwent conventional (n = 26; mean age, 71.5 years) and endovascular (n = 25; mean age, 76.4 years) AAA repair. Levels were drawn before surgery and at 1 month and 3 months after surgery. Eight patients for endovascular repair had endoleaks identified on postoperative computed axial tomographic scans. RESULTS: No correlation existed between preoperative plasma MMP-9 levels when compared with age, gender, or aneurysm diameter. No significant difference in preoperative plasma MMP-9 levels or AAA diameter was identified between patients with conventional repair compared with endovascular repair. Of the 51 patients, 33 had follow-up samples available for analysis. A significant increase in mean plasma MMP-9 levels was noted 1 month (149.5 +/- 40.1 ng/mL) after conventional AAA repair compared with preoperative levels (83.9 +/- 26.1 ng/mL; P <.05) and remained elevated 3 months after surgery (129.8 +/- 56.6 ng/mL). In those patients who underwent endovascular aneurysm exclusion without endoleak, a significant decrease in mean plasma MMP-9 levels was noted at 3 months (27.4 +/- 5.2 ng/mL) when compared with preoperative values (60.8 +/- 8.8 ng/mL; P <.01). In contrast, patients with endoleak after endovascular exclusion did not have a significant decrease in plasma MMP-9 levels at 3 months. CONCLUSION: Plasma MMP-9 levels remain elevated for as much as 3 months after conventional AAA repair, whereas successful endovascular exclusion of an AAA results in decreased plasma MMP-9 levels by 3 months. MMP-9 may have clinical value as an enzymatic marker for endoleak after endovascular AAA exclusion.