Endovascular repair of abdominal aortic aneurysm with chronic dissection using an intravascular ultrasound-guided reentry catheter.

The incidence of aortic dissection is rare (approximately 10 cases per 1 million inhabitants' year), and reports of an associated aortic dissection within an abdominal aortic aneurysm (AAA) are anecdotal. Historically, such a dissection was treated by operation, but operative risks often excluded patients from intervention. An endovascular approach appears to be more advantageous, but concerns regarding "true" versus "false" lumens and the presence of an intimal flap make an endovascular intervention potentially hazardous. In this report, the authors describe a novel endovascular repair of an AAA with an Excluder device and the successful treatment of a concomitant abdominal aortic dissection using intravascular ultrasound and a Pioneer guided reentry catheter.

Retrievable inferior vena cava filters: initial clinical results.

Anticoagulation is the accepted therapy for patients with thromboembolic disease. When contraindications to anticoagulant therapy are present, however, interruption of the inferior vena cava (IVC) may prevent pulmonary embolism (PE). The objective of this study was to report our early technical and clinical results with retrievable IVC filters (IVCFs) for the prevention of PE. One hundred and twenty-seven multitrauma patients between December 1, 2002, and December 31, 2004, underwent placement of Gunther-Tulip (n = 49), Recovery (n = 41), or OptEase (n = 37) retrievable IVCFs under real-time intravascular ultrasound (IVUS) guidance. All patients had abdominal X-rays to verify filter location. Prior to IVCF retrieval, all patients underwent femoral vein color flow ultrasonography to rule out deep vein thrombosis (DVT) and vena-cavography to assess the IVCF for trapped emboli, filter tilt, or retrained thrombus. Thirty-nine patients died of their injuries; no deaths were related to IVCF placement. One PE occurred during follow-up after filter retrieval, and two femoral vein insertion-site DVTs occurred. One hundred twenty (94.4%) of IVCFs were placed without complication at the L2-3 level, as verified by abdominal X-rays. Filter-related complications included three groin hematomas (2.9%) and three IVCFs misplaced in the right iliac vein early in our experience (2.3%); these filters were uneventfully retrieved and replaced in the IVC within 24 hr. Sixty-six patients underwent uneventful retrieval of IVCFs after DVT or PE anticoagulation prophylaxis was initiated. Forty-five IVCFs were not removed: 41 due to contraindications due to anticoagulation and four because of trapped thrombus within the filter. The role of retrievable IVCFs continues to evolve, but in this study of 127 patients, prophylactic temporary IVCF placement was simple and safe, prevented fatal PE, and served as an effective "bridge" to anticoagulation. Further investigation of this bedside IVUS technique and the role of temporary IVCFs in different patient populations is warranted.

Transthoracic cuffed hemodialysis catheters: a method for difficult hemodialysis access.

BACKGROUND: Recurrent vascular access failure is a major cause of morbidity in patients receiving long-term hemodialysis. Central venous catheters are often necessary for dialysis, and easily accessed vessels (ie, the internal jugular vein and subclavian vein) frequently occlude because of repeated cannulation. When standard access sites occlude, unconventional access methods become necessary. We report a technique of placing hemodialysis catheters directly into the superior vena cava (SVC). METHODS: Between January 2002 and December 2004, 22 patients with documented bilateral jugular and subclavian vein occlusion underwent transthoracic SVC permanent catheter placement. Femoral vein access was obtained, and a sheath was placed. Under fluoroscopic guidance, a diagnostic catheter was then inserted into the SVC, and a venogram was obtained. By using the fluoroscopic image as a reference guide, supraclavicular access directly into the SVC was performed with lateral and anteroposterior views to better localize the SVC. Once venous blood was obtained, a hydrophilic wire was passed into the inferior vena cava. A 5F sheath was then placed, and, with the use of an exchange catheter, the wire was switched for a stiffer wire. The hemodialysis catheter was then placed in the standard fashion over this wire. RESULTS: In a 24-month period, 22 patients underwent transthoracic permanent catheter placement. All patients had the permanent catheters successfully inserted. Two major complications occurred. One patient experienced a pneumothorax, and another patient experienced a hemothorax. Both patients were successfully treated with chest tube decompression. All permanent catheters functioned immediately with a range of 1 to 7 months. CONCLUSIONS: Transthoracic permanent catheter placement is an appropriate alternative for patients in whom traditional venous access sites are no longer available.

Traumatic superior mesenteric arteriovenous fistula and aortic pseudoaneurysm 20 years after repair.

A case of traumatic superior mesenteric arteriovenous fistula (SMAVF) and aortic pseudoaneurysm successfully treated by a unique combination of operative and endovascular techniques with a 20-year follow-up is reviewed. After 20 years, the patient presented with an aortoenteric fistula, which was managed with a cryopreserved aortic interposition graft. In this report, we review the evolution of the treatment for traumatic SMAVF and aortic pseudoaneurysm and the current management of aortoenteric fistula.

Prevention of intimal hyperplasia; Initial results with low-dose beta-radiation applied by an external vascular polymer wrap.

OBJECTIVE: Endovascular brachytherapy, delivered by a variety of catheter-based devices, has proven clinically effective for the inhibition of neointimal hyperplasia (NIH) after coronary and peripheral balloon/stent angioplasty. No platform, however, has been developed to deliver low-dose radiation in concert with vascular surgical operations. The purpose of this study was to evaluate the vascular response following balloon injury to the rabbit carotid artery, with and without topical low-dose 45Ca, applied by an external vascular "wrap". METHODS: Twelve rabbit carotid arteries were subjected to balloon injury by embolectomy catheter. The common carotid artery was then "wrapped" circumferentially with a biostable polyurethane membrane (Nanoskin Secant Medical, Perkasie, PA), without radiation (n = 6), or with radiation (n = 6) (45Ca approximately 50 microCi). The animals were sacrificed at 4 weeks for histologic assessment of the treated vessels. RESULTS: The 45Ca wrap inhibited NIH evidenced by trends towards reduction of intimal area (0.46 +/- 0.19 control carotid vs. 0.35 +/- 0.15 (45)Ca-treated carotid arteries; P = .11), maximal intimal thickness (0.21 +/- 0.08 vs. 0.16 +/- 0.05; P = .12), average intimal thickness (0.12 +/- 0.06 vs. 0.08 +/- 0.03; P = .08), marginally significant reduction in percent area stenosis (33 +/- 15% vs. 21 +/- 9%; P = .06) and marked neointima suppression in areas immediately adjacent to 45Ca wrap remnants. Medial necrosis (P = .003), however, was observed slightly more for 45Ca-treated carotid arteries versus control arteries. CONCLUSION: Low-dose 45Ca beta-radiation labeled onto a polyurethane membrane appears to inhibit NIH in an animal model.

Gene expression patterns in human liver cancers.

Hepatocellular carcinoma (HCC) is a leading cause of death worldwide. Using cDNA microarrays to characterize patterns of gene expression in HCC, we found consistent differences between the expression patterns in HCC compared with those seen in nontumor liver tissues. The expression patterns in HCC were also readily distinguished from those associated with tumors metastatic to liver. The global gene expression patterns intrinsic to each tumor were sufficiently distinctive that multiple tumor nodules from the same patient could usually be recognized and distinguished from all the others in the large sample set on the basis of their gene expression patterns alone. The distinctive gene expression patterns are characteristic of the tumors and not the patient; the expression programs seen in clonally independent tumor nodules in the same patient were no more similar than those in tumors from different patients. Moreover, clonally related tumor masses that showed distinct expression profiles were also distinguished by genotypic differences. Some features of the gene expression patterns were associated with specific phenotypic and genotypic characteristics of the tumors, including growth rate, vascular invasion, and p53 overexpression.